Ocean Infinity’s technology uses multiple underwater drones and surface vessels with a single host vessel
Yesterday, a support group for MH370 families released a statement claiming that a private entity has offered to resume the seabed search for the aircraft with the understanding that it would collect a fee only if the aircraft wreckage was found. Today, through Grace Nathan, a Malaysian lawyer whose mother was a passenger on MH370, we learn that the private entity is a US-based firm called Ocean Infinity.
Readers here are already familiar with Ocean Infinity. In a recent post entitled Advanced Underwater Drones May Help Find MH370, I highlighted the innovative research at Virginia Tech in developing underwater autonomous vehicles (AUVs) that could collaboratively scan the ocean floor. In an update to the article, I stated:
I was recently in a discussion that included a well-known ocean explorer who happens to be a judge in the Ocean Discovery XPrize competition. We were having a general discussion about searching for MH370 and ways to scan the ocean floor at high resolution, and he told us about the capabilities of Ocean Infinity. Like the team at Virginia Tech, their approach is to employ a team of AUVs. From their website:
Six HUGIN autonomous underwater vehicles (AUVs) are capable of operating in 6,000 m water depth collecting high resolution data at record breaking speeds. Our AUV fleet is accompanied by six unmanned surface vehicles (USVs) to ensure precise position and constant communication.
With multiple autonomous vehicles working simultaneously utilizing innovative technology, we are able to survey huge swaths of the seabed, quickly and with outstanding accuracy. We can operate in shallow waters but excel in extreme depths, working in dynamic environments ranging from the tropics to the Arctic ice.
Because of the size and complexity of each AUV/USV pair, the capital cost of the technology from Ocean Infinity would greatly exceed the capital cost of Virginia Tech’s technology, which uses small AUVs with innovative navigation systems. On the other hand, both approaches benefit from having a single host vessel supporting multiple underwater vehicles, which offers significant operating cost and scan rate improvements compared to the conventional towfish technology.
Ocean Infinity’s seabed exploration system is commercially available today, including underwater and surface vehicles, on-board support equipment, and the host vessel. This is an exciting possibility for conducting the search for MH370 in the near future.
I can now say that the “well-known ocean explorer” was David Mearns. At the time that I posted the article, I was not aware that Ocean Infinity had any interest in searching for MH370, although I was hoping they did. The prospect of exploiting Ocean Infinity’s technology in the near future is great news.
That means that Malaysia, Australia, and China need to make a decision: Either the tri-partite countries should provide funds to re-start the search; or, the countries should fully cooperate with Ocean Infinity and other qualified entities that are interested in re-starting the search. Any other action is unacceptable.
OI’s technology is superior to what was used in 2014-2016. Large areas can be explored much faster. Before rushing to S35, the next search team should carefully consider all the options, including S35 and S30, prioritize and then execute until MH370 is found. Time to get public and private sector expertise around the same table to solve this mystery. That includes NOK, OI, ATSB, CSIRO, DM, BG, IG…
@ALSM: Mike, I agree. We need to also set realistic expectations about the probability for success of any one area, which has not been done in the past. Perhaps in the next report from ATSB they can present more data about the surface search around 30S. They are putting a lot of weight on the assumed efficiency and thoroughness of the search in that area to conclude that the impact site was further south.
Interesting good news.
“Any other action is unacceptable.”
Strong words. We have an apparent conflict between those who want to find the aircraft (the public), and the powers that be (Malaysia, others) for whom “letting sleeping dig lie” may be the best approach.
Let Sleeping Dogs Lie, old saying means-
(idiomatic) To leave things as they are; especially, to avoid restarting or rekindling an old argument; to leave disagreements in the past. Eventually, they decided it would be best to let sleeping dogs lie and not discuss the matter any further.
@Victor Iannello
Victor, you said “@Rob: You are going to have a hard time persuading people to ignore the drift studies that say that 38S latitude is too far south.”
Thank you for advising me on that. My response is that possibly, hopefully, future searchers will turn their attention to the area downrange of S38 (downrange of the BM hotspot) after they have failed to find the aircraft at either S30 or S35.
@Rob: More likely they would proceed either further out from the arc or further north.
@Victor
“with the understanding that it would collect a fee only if the aircraft wreckage was found”
Collect a fee from whom? Certainly the NOK cannot foot the bill. Malaysia has gone on record as saying they will not provide a reward to someone who finds the wreckage. Australia and China have been quiet on this issue. Until someone credible offers a reward or the fee is placed in escrow, I doubt the search will be resumed.
@DennisW: The tri-partite countries would have to agree on how to split the fee. For a number of reasons, I am much more optimistic than you are that arrangements can be made.
It’s encouraging that the AUV technology is progressing at the rate it is. The Infinity fleet AUVs seem to be similar to the Dorado-class sea-floor mapping AUVs developed by the Monterey Institute [MBARI], which have been producing spectacular science in the eastern Pacific. Of course, a fleet of AUVs with surface AVs would be vastly more productive than one large surface vessel with tow-fish.
A question that comes to mind — is the nature of deep water debris fields from large aircraft well-enough characterized — that is, is there room/need for developing better recognition software? I get that much of the analysis is eye-ball intuitive. But if there is a trade-off of speed of data acquisition and quality, an automated recognition system might get the most out of AUV exploration.
DrB wrote at 2:34 am: “I get lift coef = 0.04669 (sic) (in agreement with G.) and (from chart above) drag coef = 0.0361 at M0.84. That’s quite different from the 0.0241 quoted as being from Professor Obert’s chart. Any idea why they are so different?”
There can be a number of reasons for the differences. We don’t know what prof. Obert’s chart represents. It could be data obtained from windtunnel tests without tailplane at an unknown Reynolds number, or trimmed data at an unknown center of gravity. We also don’t know the airplane type for Figure 11-6 in Boeing’s Jet Transport Performance Methods. Most examples given elsewhere in the book are for a B757-200 with PW2040 engines. For the purpose of this discussion I’ll assume Fig. 11-6 is also for a B757-200. The following Obert/JTPM comparison may serve as an illustration of some differences.
The first chart compares the low-Mach drag coefficients versus lift coefficient-squared. For most airplanes that relation is approximately linear at lift coefficients well below the stall. The difference in slope between the two lines corresponds approximately to the difference in wing aspect ratio between the B757-200 and the B777-200. The difference in zero-lift drag coefficient is suspect (see above).
The second chart compares the variation of drag coefficient vs Mach at cL=0.5. Apart from the differences in zero-lift drag coefficient and drag-due-to-lift noted earlier, that comparison illustrates the effect of differences of wing planform and airfoil sections between the B757 (designed for cruising at Mach 0.80) and the B777 (designed for cruising at Mach 0.84).
@ikr
The Dorado class AUV’s used by MBARI use a Kearfott INS system together with a Doppler velocity sensor. The Infinity fleet is more similar to the Virginia Tech approach, and is completely unproven and untested technology.
Ocean Infinity does have an app for sale in the Apple iTunes store.
https://itunes.apple.com/us/app/ocean-infinity/id1165828775?mt=8
Hard to actually determine who Ocean Infinity is. Their US phone number goes to SeaTrepid – a Louisiana based company. Their European phone number goes to someplace in Norway. Tracerouting their info IP address ends up in a cloud computing company in Texas – rackspace.net via telia.net – a European carrier.
I don’t have a good feeling about these guys despite Victor’s “optimism”. We shall see.
As far as ALSM’s cadre of advisors – “That includes NOK, OI, ATSB, CSIRO, DM, BG, IG…” I would be a lot more comfortable with Metron who actually has some pedigree.
@@VictorI,
Yes, there was a typo. The lift coefficient should have been 0.4669.
@Gysbreght
Thanks for the comparison of the drag curves. I guess I’ll have to shell out to buy Obert’s book to get the graph I need. You are correct in that Figure 11-6 in JTPM is not for a 777 because L/D is too low. The difference in aircraft type explains the discrepancy in drag coefficients.
Here is a paper on the 777-200ER that gives low-speed zero drag coefficient as 0.01395 and K as 0.04885 :
https://drive.google.com/file/d/0BzOIIFNlx2aUUElPV3BhekxQdUE/view?usp=sharing
I don’t trust the variation shown with Mach, though.
@DrB: You’ve referred to that paper earlier. I have pointed to some of the many errors it contains and advised not to use it as an authoritative source for anything.
A statement like: The drag polar coefficient CD0 and K are assumed to be constant up to the cruise Mach number (MCruise). However, CD0 and K are expected to become function of Mach number above the cruise Mach number. is not based on anything and is simply wrong. The values of CD0, K and Mach-effect are presented without any derivation or reference and seem to be just picked out of thin air.
You may wish to give the paper a more critical reading.
@DrB: “I guess I’ll have to shell out to buy Obert’s book to get the graph I need.”
If I remember correctly, Victor Iannello posted that graph after a suggestion from Kenyon. I left it to Victor to post it again. More interesting than the graph would be any context and comment that prof. Obert adds in his book.
@DennisW
The OceanInfinity fleet uses a similar specification Kongsberg Hugin as was used by Fugro, not new & untested, quite the state of the art.
The Autonomous Surface Vessels, six ASV Global C-Worker 8, are less well proven but use the positioning and tracking tech that is common to single, manned, host vessels. I’d expect the major commissioning challenge to be the software integrating it all (supplied by 4D-Nav).
The Bergen connection is Swire Seabed, the owner of the Host Surface Vessel that has been leased to OI.
Do review the research papers: CSIRO dunked the real flaperon into the water to determine its leeway which was then integrated into the drift simulation that, in turn, exploits their ocean model (which is in no way trivial). If you’re thinking about Metron’s contribution to the AF447 search, that didn’t need a complex drift simulation & leeway analysis as a database of 1000 recovered debris items had been catalogued. CSIRO’s work might still be 700/500/300/100km out, but someone needs to ‘get back in the sea’ to work that through.
If the answer can’t be more precise, a faster path to determining the answer is a good alternative.
@Don
Yes, on the Ocean Infinity surface vehicles. My understanding is the AUV’s use acoustic positioning similar to the Virginia Tech approach. Do you have any reference to work that Ocean Infinity has actually performed – reports, documents, whatever,…?
@Don
BTW, my heartburn with CSIRO’s work is that it is fundamentally a forward drift model which is intrinsically flawed relative predicting the probability distribution of the source of debris. Works great if you want to know where something will go.
@DrB:
Here is a link to Ed Obert’s complete textbook:
http://rahauav.com/Library/Aerodynamic/Aerodynamic_design_of_transport_aircraft_www.rahaUAV.com.pdf
@DennisW,
OceanInfinity: yes, mesh comms between the HSV, ASVs and UAVs for mission cotrol but HiPAP USBL to the AUVs for positioning.
The HSV left Portsmouth, UK, only a week or so ago with the full complement of ASVs (they were visible, the nice ship spotter guys posted some new images at MarineTraffic). I assume the AUVs were embarked also, but they’re not visible as stored in a hangar. I assume, and I do not know any more, that it’s some form of trials that is being undertaken so no reference papers yet.
@Victor Iannello: Thanks for the link to Ed Obert’s textbook. Not adding much to the graph in question, but interesting nevertheless.
Shipwreck hunter David Mearns explains why he wants to find MH370
http://www.abc.net.au/radio/perth/programs/mornings/who-are-you-david-mearns/8767570
David Mearns has discovered some of the most elusive shipwrecks in history.
Among his most notable finds was the HMAS Sydney which sank off the WA Coast, when it was attacked by the German raider Kormoran in 1941. All 645 on board perished.
David has had an extraordinary career finding things that were thought to be lost forever.
His reflections are detailed in his new book called The Shipwreck Hunter.
David also explains why he wants to find MH370.
He is speaking to Geoff Hutchison on Who Are You?
Duration: 25min 56sec
Broadcast: Wed 2 Aug 2017, 10:30am
Published: Wed 2 Aug 2017, 3:24pm
(Times are Perth Australia = UTC +8)
@Ventus
I would be great if you could post a link to the publication. I have very limited bandwidth in the boonies. Thanks in advance.
@all: so, ZERO hard data exists that would help inform a likelihood estimate for the FDR/CVR being anything but a hunk of corroded metal?
I’d have thought that would be one of the most critical pieces of data a serious researcher would try to collect. And it speaks directly to this forum’s penultimate topic, because the private search guy seemed to consider FDR/CVR recovery a key mission objective.
If none of you have any hard data, I’ll find it on my own, I guess, when I get a moment to spare.
@DennisW
It is a radio interview, very interesting regarding him and his life and work, but only the last couple of minutes are MH370 related.
The mp3 file is 11.8 megabytes.
http://mpegmedia.abc.net.au/radio/local_perth/audio/201708/acf-2017-08-02-who-are-you-david-mearns.mp3
@TBill , ‘let sleeping dogs lie’
Just recently MAS CEO said ‘there will be advances in science that will help locate the wreckage eventually’. In others words, somewhere in a far future, but not the present time. I hope I am proven wrong in saying ‘MY and/or MAS will come out with an elaborately woven story as to why a reward will not be forthcoming ‘. A new search is not in their benefit for their own selfish reasons. When ‘eventually’ comes around the corner they are confident nothing of interest will be gleaned from the wreckage.
@Brock
I answered your post.
@Brock McEwen
RE: “so, ZERO hard data exists that would help inform a likelihood estimate for the FDR/CVR being anything but a hunk of corroded metal?”
For what it’s worth, the DFDR/CVR technical standards require that the Crash Survivable Memory Unit (CSMU) must withstand immersion for a minimum of 30 days at a depth of 20,000ft (6,100m). There doesn’t appear to be any published data that shows the maximum time that CSMU memory boards might survive underwater, but the AF447 CSMUs were retrieved after nearly two years at a depth of almost 13,000ft (3,900m). After cleaning, the memory boards were read and data retrieved without too much trouble. The AF447 experience suggests the CSMU memory boards should survive underwater much longer than required by the standards. I’ll be very surprised if you find any other ‘hard data’.
@VictorI,
Thanks for posting the link to Professor Obert’s book. There’s not a lot there relevant to the B777-200ER (and nothing I could find on the 300ER). Still, his chart may be the best public data on a drag polar for the 200ER. I will model it, put it in my fuel model, and compare the fuel flow predictions to the Aero Figure 1 (as you have already done).
@Andrew
The issue has to due with the fact that an unpowered SSD will experience data decay that depends on the usage of the media, the write temperature, and the storage temperature. It really has little to do with the specific application. Not long ago there was a “media frenzy” on the storage time issue. There is a lot of data out there in response to those hysterical claims.
A very good starting point is the linked summary below:
http://www.anandtech.com/show/9248/the-truth-about-ssd-data-retention
The usage history in the MH370 black boxes is not known, but assuming a worse case – that the drive is at the edge of capacity loss due to retired blocks. Another reasonable assumption is a 30C write temperature. That is very conservative and it is likely to be higher. With these two conditions the table in the link shows a doubling of life for every 5C degrees of storage temperature decrease starting with a base of 32 weeks at 30C. The bottom of the ocean should be near 5C (Again, being conservative I used 10C.) Doubling every 5C from 30C to 10C predicts 512 weeks or some ten years.
Another factor is that the data shown is for consumer grade data readers like you and I would use. You can be sure that the drive data will be read by specialists who have control over highly adjustable and dynamic read thresholds with specialized equipment that would extend the data recovery even further.
Bottom line is that there is still lots of time left, but the clock is ticking. My answer to Brock was 4 to 6 years again in the interest of ultra-conservatism since I do not know the pedigree of the memory used or its write history. It could be that the memory is over a decade old, and not up to modern performance standards.
@DennisW
Thanks.
Both Ocean Infinity and Malaysia confirm that they are negotiating the details of what Malaysia has called a “good offer” to search for MH370 for a reward if found.
@Victor
Will the reward be specific to Oceon infinity and there associates. Or will it be open to others offering their search capabilities? If accepted this may Perhaps encourage others to try. Sounds like Whoever tries would have to have top notch capabilities and the right guidance. IMO the more searchers the better and quicker chances.
@Victor
…nice development
@DennisW
…nice discussion. Do we know from the surveys the temperature of the water in the depths they searched (cold I know <5 deg C)? Asking too much but, what about in the shallower areas around 30S (6000-9000 ft)? I am probably expecting empty flight recorders (data recorder turned off by breaker), but Greg Feith (former NTSB) points out even then the data should have some use to determine when the data recorder was turned off and what happened up to that point.
@TBill
I don’t have any expertise in ocean water temperature versus depth, but all the data I looked at shows 5C or so once you get below the thermocline (~1000m). Speaking of the thermocline, it is this temperature gradient and surface turbulence that makes me very suspicious of acoustic navigation relative to the AUV’s proposed for use by Ocean Infinity.
The holy grail of commercial positioning these days is indoor positioning both for personnel tracking (first responders etc.) and for interior construction. We spent a lot of time looking at acoustic solutions, and could never make them work even for crude first responder tracking much less for precision placement of duct hangers etc. The speed of sound is a strong function of temperature, and sound waves are very susceptible to media disturbances (i.e. air currents).
@TBill
RE: “I am probably expecting empty flight recorders (data recorder turned off by breaker),”
I’m sure it’s been said before, but the circuit breakers for the DFDR and CVR are buried in the MEC and are not accessible from the cockpit. While not impossible, I think it’s highly unlikely that a rogue pilot would have been able to pull them.
The CVR is likely to be of limited use if the unresponsive pilot scenario turns out to be correct, because the CVR only records the last 120 mins of communications and other sounds in the cockpit. Nevertheless, it might help confirm that no activity was occurring in the cockpit. If sounds indicating activity (eg seat movement, coughing) are recorded, then that would confirm that someone was alive during the last two hours of flight and might help confirm the rogue pilot theory. The DFDR, on the other hand, can record 25 hours of data. It should provide a much better indication of what occurred, assuming the data is recoverable.
@Andrew
Yes I am thinking there might have been a trip to the EEBay before or during the flight. My fear/expectation is whatever could be disabled was disabled such as DFDR and ELT.
@Andrew
My question for you would be, let’s say the DFDR was switched off before the flight by circuit breaker, would that be known on the flight deck before the flight? If there was an indicator light, I would be prepared to tape it over or find a way to disable the light. Just to indicate my philosophical mindset. In the future I think ACARS needs to check that, assuming it doesn’t do it now.
@DennisW
“Speaking of the thermocline, it is this temperature gradient and surface turbulence that makes me very suspicious of acoustic navigation relative to the AUV’s proposed for use by Ocean Infinity.”
I had the same thought, but if the surface tracker remains directly above the AUV beneath it, the two way sound path between them is presumably travelling through the thermocline (and the overall thermal gradient) at right angles to it, so, said sound waves should not be deflected much, if at all.
@TBill
RE: “My question for you would be, let’s say the DFDR was switched off before the flight by circuit breaker, would that be known on the flight deck before the flight?”
Yes, a ‘FLT RECORDER SYS’ status message would be displayed on the EICAS. EICAS messages are displayed on LCD screens, so you’d look a bit silly trying to cover it up with tape! I doubt the message can be cleared if the recorder remains inoperative.
@Andrew: Might it also generate an ACARS message?
Anybody recognize these dudes?
@Victor
RE: “Might it also generate an ACARS message?”
Yes!
@Ventus
True on deflections in your example, but there will be variable path delays.
In any case, Virginia Tech has smart people, and I assume a lot of smart people associated with Ocean Infinity are well aware of the issues as well. I am not going to second guess them. Just thinking out loud relative to what I would find daunting. Bats seem to do a fantastic job navigating with acoustics in air with a brain the size of a small marble, so we know it can be done.
@all: so the world record for surviving in the ocean at depth is two years?
@Brock
The data shows much longer survival rates are expected. Quit playing the wounded eagle. The two year period of a previous recovery is not relevant to predicting what the SSD data life is likely to be.
@DennisW
You previously stated that data decay “depends on the usage of the media, the write temperature, and the storage temperature”. Does extremely high pressure, as would be found at the bottom of the ocean, have any effect on data retention?
@Victor
Nice photo!
@DennisW
I’m not sure the memory device technology is a Crash Survivable Memory Unit (CSMU) is ‘flash’, a number of references describe EEPROM.
An issue with what is now generally termed flash is that storage locations aren’t byte addressable for all operations, page or block limitations apply, and changes require an erase-overwrite process. Flash device ‘endurance’, i.e. lifetype write operations, is finite. EEPROM may be the technology employed in data recorder CSMUs.
The applicable specification (in Europe, EUROCAE ED55 and 56a) states that the CSMU must be resilient to 30 days exposure at a maximum depth of 20,000ft (6096m). Note that minimum operational performance specification relates to the CSMU and not its components.
There is documented forensic capability to read out EEPROM state using scanning electron microscopy as a means to image the actual semiconductor structure of the device. If the encapsulated ‘chip’ is resilient to pressures at 6000m then a possibility of data recovery is real.
@Don Thompson
See p.15:
Honeywell SSFDR
@Victor Iannello
Yes Victor, I recognize those dudes. But the question is, would you buy a uses auto from either of them? I wouldn’t.
@Don
The exact type of memory used in the recorders is indeed sketchy. I am quite certain it is a form of nand flash. Most likely of the SLC type. The term EEPROM is frequently (and confusingly) used to describe flash memory.
If you come across a solid description of the exact memory used please post. The link below to a Honeywell description is about the best I have been able to find.
http://visualjournalism.com/wp-content/uploads/Flight_Data_Recorder_(SSFDR).pdf
@Andrew
Hey, you beat me to it :-).
Flash memory (36 Mbyte, Flash EEPROM) should be good for decades as long as it was not damaged.
@Andrew
@TBill
Re “I’m sure it’s been said before, but the circuit breakers for the DFDR and CVR are buried in the MEC and are not accessible from the cockpit. While not impossible, I think it’s highly unlikely that a rogue pilot would have been able to pull them.”
Andrew, it’s very unlikely this particular rogue pilot would want to try and deactivate the FDR, even if he had been able to. Imo, his plan was to fly the aircraft into a remote part of the SIO, and sink it in deep water, making sure to leave no clues as to its final location. If it all went to plan as he intended, the plane would be lost forever.
@Andrew
OK so not so easy pre-disable DFDR (and O2 drop down masks), *if* the EICAS message does not go away upon button push of CLR. I know what you mean from FS9 screen.
@Andrew
“You previously stated that data decay “depends on the usage of the media, the write temperature, and the storage temperature”. Does extremely high pressure, as would be found at the bottom of the ocean, have any effect on data retention?”
I don’t think so.
@Victor
That is very nice photo of two folks instrumental in trying to find MH370. Part of the reason we need to find MH370 is to make all the human intellectual work by yourself, BG, Inmarsat, IG, ATSB, and others I missed provide the value to society that the effort deserves to achieve.
@Rob
I am with you on everything up to the flight path and strategy. I see MH370 possibly similar to SilkAir as far as turning off DFDR and all. I envision trying disguise flight path to SIO, so probably no immediate FMT off Sumatra, and making crash look unintenional if discovered. Possibly crash is on L894 flight path at 22S, but right now I favor ATSB’s 32-36S area (inside Arc7) getting over Broken Ridge. I currently feel MH370 may have begun descent after Arc5 at twilight so that’s how I get inside Arc7 for crash site – I am not seeing a ghost flight dropping like rock into ocean from FL350. I do not have explanation for debris/flaperon erosion except to say if pilot is flying aircraft, I then can take the liberty for end-flight maneuvers to explain BFOs and state of debris.
@ALSM
“Flash memory (36 Mbyte, Flash EEPROM) should be good for decades as long as it was not damaged.”
Yes. Using the Intel data and most likely record and storage temperatures you get 30 to 40 years. I derated everything along the way just to be absolutely worst case. Probably double the 30 to 40 years using lab grade read technology. Basically it is a non-issue as you imply.
@Andrew, DennisW, & ALSM
Yes, that publication has been on my ‘bookshelf’ for some time.
It states 36MB Flash EEPROM, I agree that is confusing terminology. Given the era, early/mid 1990s, when the DFDR was introduced for the B777, flash (NOR or NAND) exploitation was relatively immature while E²PROM was well established. I’d expect E²PROM to be used.
The characteristics of ‘true’ E²PROM would be more suitable, than NAND flash, for a safety critical design. This reference articulates the issue well.
Flash is a ‘page’ addressable device, it presents a limitation where overwrites must be preceded by a page erase function. The process implied by the page erase function is its weakness. The endurance for a flash device that operates in a write dominant environment is poor, so much so that enterprise class storage systems only adopted solid state devices (NAND, SLC, flash) approx 10 years ago. Contemporary flash storage devices, by means of their embedded controllers, mitigate the endurance problem by exploiting hidden, overprovisioned, capacity to map in unused pages as defects occur, and wear levelling techniques.
DFDR storage would imply a complete overwrite (i.e., with flash, page erases) every 25 hours of operation. In essence, flash wears out when used in a write dominant environment: endurance is compromised and persistence (data retention) diminishes. The latter is described by Cypress Semiconductor.
It’s notable that the requirements (ED-55 and ED-56a) set out for the recorders state immersion requirements for a 30 day period. The ULB battery life requirement was also 30 days. Adoption of the recommendation for 90 day ULB operating requirement would require a revision of other ED-55 and 56a criteria so as to remain consistent.
Why not defer worrying about data recoverability until the debris field is located? There would be plenty else to learn if we got that far. Of course some of the worry expressed in this thread comes a Pyrrhonian who thinks that any MH370 debris field itself might be a Malaysian plant! Infinite regress, folks.
@Don
Yeah, I tried a historical perspective, and decided that since 9M-MRO was delivered in 2002 I would use that as a baseline for component pedigree. Not a particularly great reason I know.
You could certainly be right, but I think the conclusion is that it makes no difference relative to data recovery. We should be good regardless. It would be fun to know what was actually used in the 9M-MRO data recorder.
@ALSM What do the abbreviations stand for? “d. Time to get public and private sector expertise around the same table to solve this mystery. That includes NOK, OI, ATSB, CSIRO, DM, BG, IG… “
@Kaz: Welcome to the discussion. Here is what that alphabet soup means:
NOK = Next of Kin
OI = Ocean Infinity
ATSB = Australian Transport Safety Bureau
CSIRO = Commonwealth Scientific and Industrial Research Organization
DM = David Mearns
BG = Blaine Gibson
IG = MH370 Independent Group
@Don Thompson
@Dennis W
RE: “Given the era, early/mid 1990s, when the DFDR was introduced for the B777…”
“…I tried a historical perspective, and decided that since 9M-MRO was delivered in 2002 I would use that as a baseline for component pedigree.”
I think Dennis might be close to the mark. The FAA’s regulations for DFDRs have changed several times since the early 1990s in response to recommendations made by the NTSB. The regulations applicable to transport category aircraft manufactured after 18 August 2000 require their DFDRs to record a greater number of parameters. Given that 9M-MRO was manufactured in May 2002, I’d guess the Honeywell SSFDR to be c.2000 technology.
Following on from above, the accident reports for a couple of B777s that were manufactured in 1997 (MH17: 9M-MRD, MS667: SU-GBP) state that those aircraft had the Allied Signal 980-4700-003 DFDR. The earlier -003 model has less memory (18Mb) and a lower data rate than the -042 model fitted to 9M-MRO.
@Andrew, and DennisW
Developments through 1990s: additional storage capability could readily be accomodated with an additional card or denser devices in the CSMU. Lifecycle management, considering upgrade capacity to the CSMU using same technology, is a simpler process than adopting a new technology.
My core concern is that NAND flash implies risk, it being inherently less reliable & its persistence is prone to deterioration. Persistence, during exposure to extreme environment, is the issue here. E²PROM avoids these risks, permits a simpler design. Existing studies describe deep forensic recovery of data from E²PROM. If eventual readout is not straightforward, I’d prefer that the tech is not NAND flash.
Perhaps worth noting that AIMS (v1 and v2, also Honeywell hardware) employed E²PROM memory for FMS storage. This is specifically noted in a Mitre Corporation report discussing FMS Database Capacity.
Setting aside discussion of the aircraft recorders’ memory tech, there have been comments that any passenger PEDs found among debris may also hold information pertinent to an investigation.
@Andrew,
(Comments crossed) doubling capacity and data rate is readily achieved if the device count in the CSMU is doubled: twice as many devices to concurrently write to.
Getting back to the post, it has been reported that Ocean Infinity made its offer months ago. It would seem that time is clicking away if the search is to resume during the upcoming favorable season. I fear that Malaysia will try to run out the clock if there is not public pressure to proceed.
@Victor
“It has been reported that Ocean Infinity made its offer months ago.”
Wow: that’s simply outrageous. Did the bureaucrats of Putrajaya think they could simply ignore the proposal from OceanInfinity and hope it would never come to public attention?
Fugro exploited the southern summer weather window for AUV operations from January 2015, with Fugro Supporter, and December 2015, with Fugro Havila Harmony.
Ocean Infinity has been undertaking operations over the last two weeks after picking up last two ‘boats’ for its full complement of ASVs and, presumably, AUVs. It appears to be shakedown time for the full configuration.
@Victor
“Getting back to the post, it has been reported that Ocean Infinity made its offer months ago. It would seem that time is clicking away if the search is to resume during the upcoming favorable season. I fear that Malaysia will try to run out the clock if there is not public pressure to proceed.”
There was news in January of this year about a reward being offered by Malaysia and then retracted. It could be that the Ocean Infinity offer was made in that time frame. In any case the Malay position around the end of January was that no reward would be offered. I don’t see any “developments” which would change that position. I also did not hear any explanation by Malaysia of why the idea of a reward was scratched.
Statements made about restarting the search if solid information relative to the terminus arises are certainly now in doubt. In fact they were in doubt when Malaysia scratched the reward idea. A commitment to restart the search implies a funding commitment. Putting that funding in the form of a reward is really the same thing (actually you could argue that the reward notion is even better since it eliminates the risk of a new search not finding the plane). The tripartite group has lost a lot of credibility in my view.
@Don Thompson
Thanks, I understand your concerns. I guess the obvious question is: why would Honeywell label the memory as ‘Flash EEPROM’ if it’s straight EEPROM? Another part of the Honeywell document says: ‘“State of the art” high density FLASH memory devices have enabled the SSFDR to be implemented without
need of data compression, thereby providing very high recording integrity.’
A 1991 paper Memory Technology Applications for Airborne Flight Data Recorder Systems (T.Conquest & D.DeMyer, 1991, IEEE) highlights some of the concerns you mentioned. It also states:
‘Flash EEPROM technology is relatively new and can be considered immature in its product life cycle. Tremendous progress has been made both in chip density, where Flash devices now meet and in some cases exceed thoseof Full-featured EEPROMs. and in endurance. where Flash is starting to approach Full-featured EEPROM levels. Future trends for Flash indicate a continued increase in chip densities where Flash will clearly overtake densities of Full-featured EEPROM. As stated previously, many manufacturers are adding Full-featured EEPROM features into their Flash technologies, such as memory page segmentation and data polling, permitting system designers to take advantage of the strengths of each technology.’
For what it’s worth…
“I fear that Malaysia will try to run out the clock if there is not public pressure to proceed.”
This is why I had suggested say a 60-Minutes piece (USA version) to make the public argument. But 60-Mins did not respond to my suggestion. Seems to me global media outlets (eg: CNN) do not really have the political option to pressure Malaysia if they want to continue to do business there. Also I envision some need to wait for final reports out of ATSB and Malaysia, which may yield new information and proposals, which of course, we may not agree with, but with those things pending, we could have to wait for reaction to those reports.
> DennisW says:
> @ALSM
> “Flash memory (36 Mbyte, Flash EEPROM) should be good for decades as
> long as it was not damaged.”
>
> Yes. Using the Intel data and most likely record and storage
> temperatures you get 30 to 40 years.
> I derated everything along the way just to be absolutely worst case.
> Probably double the 30 to 40 years using lab grade read technology.
> Basically it is a non-issue as you imply.
Isn’t the issue not so much the flash memory longevity,
but rather how long the FDR remains watertight under crushing deep-sea water pressure ?
@DennisW. You say, “There was news in January of this year about a reward being offered by Malaysia and then retracted. It could be that the Ocean Infinity offer was made in that time frame.”
Reports from both AFP and Reuters (that reported by News.com) imply that the response from Malaysia was as of last week. AFP quotes from it:
“”I can confirm that we have made an offer,” a spokesperson said in an emailed statement to AFP, without giving further details.
Malaysia’s Deputy Transport Minister Aziz Kaprawi confirmed a company had made an approach and was only asking for payment in the event they find the plane.
He said the firm had made a “good offer”, and added negotiations were ongoing with the country’s Department of Civil Aviation.
“The company is demanding payment in the event the wreckage is found,” he told AFP. “We have to work out the details, what we want most is the wreckage and the black box.”
He added that the agreement of Australia and China would be needed for a deal to be reached. China, where most of the passengers came from, and Australia were both involved in the search.” (quote ends)
That seems to have been a response to Ocean Infinity publicising their offer last Thursday, “Mark Antelme, of Ocean Infinity, told EFE news on Thursday that the company will resume the search for free and will ask for a reward only if it …”
Don Thompson says that the system is undergoing shake down trials. It would have been an preliminary proposal if made earlier and even now it would need confirmation that it was a goer. Contract negotiations might be complex and might need to be clear before the Governments considered it, even assuming that those other than Malaysia would see it as their responsibility and preference (just speculating about what might explain the current quiet).
@Victor. You say, “…it has been reported that Ocean Infinity made its offer months ago.” Reported where please?
I do not know of a Mearns/Blue Water Recoveries connection with Ocean Infinity. Is there one do you know?
I know that many here, will disagree with much of what follows, but I will say it anyway.
“Running Out The Clock”.
That has been the bottom line in the whole Malaysian Strategy for “handling” the “MH-370 Crisis”, quite literally – from DAY #1.
@Victor, DwnnisW, others.
Gentlemen, I respectfully submit, that it is high time, for all of us, to stop “pussy footing around” with the Malaysians, and “Call A Spade – a Spade”.
That is:- {to say the truth about something, even if it is not polite or pleasant} (http://dictionary.cambridge.org/dictionary/english/call-a-spade-a-spade)
The whole Malaysian response – literally from Day #1, has been a littany of deliberate inaction, misleading information, outright obstrucion and delays, that has made it crystal clear, to anyone with half a brain, or more, that Malaysia never did want, and certainly does not want, the aircraft found, and will do nothing voluntarily to help find it.
The facts speak for themselves.
The initial Malaysian directed South China Sea search was a farce.
The initial Malaysian radar – nee “turnback” information was deliberately withheld for many days.
The subsequent Malacca Strait search was a farce.
The Malaysians initially rejected the Inmarsat data.
The search had to be “driven” to the SIO by Jay Carney at the Whitehouse with the NTSB’s “two tracks” released via the NYT.
The subsequent SIO Air Search was derailed by Malaysia.
The subsequent Seventh Arc Underater Search was NOT the Malaysian response, it was the Australian response, and the Malaysians were very reluctant to support it.
The press conference, (shown in Australian 60 Minutes program) where the “Malaysian Officials” at the “back of the room”, (with their own microphone and lecturn mind) quite literally “SHUT THEIR OWN MINISTER DOWN” was quite telling.
The Malaysian attitude to debris collection, let alone searching for it, speakes volumes.
(In that regard, I wonder what Blain Gibson “really thinks”, (under his breath perhaps), about that.)
I don’t suppose that anyone here (having been totally immersed in ISAT data and Drift study) has “really noticed”, that the Chineese attitude, subsequent to the cancellation of the “SIO Air Search” has been one of, at best, “studied indifference” ? Perhaps they “know something” that we don’t ?
TBill says we should wait for the supposed final reports from the ATSB on the search, and the supposed Malaysian final report.
I don’t.
I think that is a stupid strategy, that only plays into the Malaysian’s hands, and indeed helps them to “RUN OUT THE CLOCK” even further.
Therfore, I think it is time for all of us “outside” the “official circus”, to totally change tack, that is, totally change our strategy.
We must now do what ever we can, to encourage, promote, and support, any reasonable independent search effort(s), with a view to finding, and recovering the aircraft, and most critically, to ensure, that if the CVR and FDR are eventually recovered, that they not, under any circumstances, be allowed to fall into the hands of the Malaysians, regardless of Annex 13, period. Furthermore, given the “wider net” of the “interested parties”, the only “Government” I would trust in this case, is the French, and thus, the ones I would trust, to actually download the recorders, would be the French BEA, and for me, personally, as an Australain, that is really saying something.
In my frank opinion, the issue is now one of “SALVAGE” under international law.
Read these.
http://www.admiraltylawguide.com/circt/11thaircraft.html
https://coast.noaa.gov/data/Documents/OceanLawSearch/Int%27l%20Aircraft%20Recovery,%20L.L.C.%20v.%20Unidentified,%20Wrecked%20&%20Abandoned%20Aircraft,%20218%20F.3d%201255%20(11th%20Cir.%202000).pdf?redirect=301ocm
http://www.jus.uio.no/lm/imo.salvage.convention.1989/doc.html
@ventus45: I am less impressed than you with how the French have acted in this incident. The flaperon report was never released, and we still know little about the judicial investigation other than reports that all passengers and crew were cleared of any suspicion.
@David: You are right. There are no reports that Ocean Infinity made its offer months ago. Those are rumors I have heard from two people. As for connections between David Mearns and Ocean Infinity, I don’t know what their relationship is other than David M., as a leader in his field, is very familiar with their technology.
@Ventus45
…I personally agree quicker action would be good…
what I was trying to say is media organizations and governments possibly have to wait for the final reports before putting pressure on Malaysia. Who knows what ATSB is going to say about recommended future search area (are they sticking with 32-26S?) and who knows what Malaysia is going to say about the accident most likely suspected cause(s)? I am just saying it is harder to put pressure on when we don’t know what they are going to say in their final reports.
@TBill: It is very likely that the ATSB will agree with the CSIRO that 35S latitude is the most likely impact site. Hopefully, details of the surface search will be released so that others can independently assess whether latitudes further north should be dismissed.
@Peter Norton
“Isn’t the issue not so much the flash memory longevity,
but rather how long the FDR remains watertight under crushing deep-sea water pressure ?”
Not ignoring you, Peter. I simply don’t have any qualifications to comment on that aspect.
@Victor.
It is true that the French have been less forthcoming than we would all have hoped, obviously, but at least they have not been “actively obstructive”. So far, the French government, is the only one that has at least not hidden the fact, that they suspect, that it was not an “accident” (in the generally accepted meaning of the word), but rather, by inference, something else, with some kind of criminal action, by someone, being clearly implied. Moreover, they are not involved in the airline or it’s operations, and thus would have no logical reason to seek to ultimately hide the truth. They are however “holding their cards” close to their chest, and given the overall situation, that may well be both prudent and necessary, from a legal perspective. I do not think we can accuse or imply that the French have been deliberately unhelpful for any naferious reason. I therefore think that your statement: – “I am less impressed than you with how the French have acted in this incident” – is a little too strongly put, since the way I read it, you are being critical of them, as opposed to simply being frustrated by them, or did I read you wrong ?
The question of who should do the recorders, if and when they are found, is an interesting discussion, for a future time perhaps, but not too far, definately BEFORE they are found.
The problem we face here, is a question of trust, or more specifically, a lack of it. It is clearly apparent that the Malaysian Government would have many reasons to be “economical with the truth”. I thus have severe reservations about the likely efficacy of any Malaysian investigation.
I don’t know if any here are familiar with the 28 November 1979 crash of Air New Zealand Flight 901 (TE-901 DC-10) on Mount Erebus, and what followed. The initial Official Report was produced by the then Chief Accident Investigator Ron Chippindale less than eight months later, on 12 June 1980. It was roundly criticised by all and sundry. The public outcry compelled the “Government of the day” to institute a Royal Commission into the matter. In the end, it took many years and TWO Royal Commissions by Justice Peter Mahon to get to the truth, which, is still disputed, by many, to this day. In para. 377 of his report, Justice Peter Mahon found that airline executives and senior (management) pilots had engaged in a conspiracy to whitewash the inquiry, accusing them of “an orchestrated litany of lies” by covering up evidence and lying to investigators.
“An orchestrated litany of lies”, (and I would add “half-truths”) is what we will face, with MH-370, and we must be “on guard” agains it.
@Victor. Thank you for your clarification.
You have said, “We need to also set realistic expectations about the probability for success of any one area, which has not been done in the past.”
Indeed. One unaddressed aspect I have carried on about is the non-discounting of earlier high search confidence by the possibility that there was a glide beyond search areas, past and proposed. Even though the assumption that the aircraft was pilotless was reasonable in the circumstances its effect on probabilities should have been assessed and quantified, or at least acknowledged explicitly.
Related, the location of the “Central America” by Metron using Bayesian analysis was close to a fluke, an intuitive second look at a very low probability (~1%) site. With MH370 there were large areas of such low probability excluded from the previous search. While that search is now passé due to developments, it is seen all the same as conclusive; by me wrongly.
I see from the Final Report ‘contents’ that the ATSB intends addressing, “……the various risks associated with the search, and the mitigations put in place”.
https://www.atsb.gov.au/publications/investigation_reports/2014/aair/ae-2014-054/
If Ocean Infinity has done its sums it will have taken all this into account.
There has been no sign of Metron volunteering.
If nothing else, Ocean Infinity will get some coverage.
Not that it helps much as to the quantification of probability but I posted some thinking on the JW blog recently about the damage evident on the recovered part of the right outer flap and whether that clarified the pilotless issue at all. The postings assumed that earlier the ATSB had it right that the flaperon and part flap separated unextended.
There was some discussion.
From my perspective the outcome is:
• The flaperon in separating hit the flap rather than vice versa. The impact broke the flap. As for the inboard part of it, that rotated horizontally, its inner end moving rearwards, pivoting around the supporting mechanism still attaching it to the wing further outboard. Those linkages twisted then broke. There was a sequence of internal strikes within the flap inner end during this by an auxiliary flap support track attached to the wing and inserted in the flap. The last was when the flap inner end was already about 8 in aft of retracted, that is the track had withdrawn that amount.
• This sequence would not occur in a high speed impact by the aircraft with the sea. There would be no time for all that; the separation of the flaperon, that striking the flap, being followed by the sequence
• It is unlikely loading of the attachments of the neutral/retracted flaperon or flap would break them mid-air in an unpiloted aircraft pitch-up, given the normal loading these are designed for when deployed fully. The wing would break first.
An indicator of the likelihood of such a pitch-up was the Silk Air 737, prevention of it (NTSB/Boeing view) requiring full manual nose down trim and a pilot.
• The remaining possible causes of the separations are:
1. Shock and whipping from a wing break during a high speed unpiloted pitch up as above.
2. Flutter during the same.
3. A piloted flaps-up ditching
• As to 2., it is unlikely that based on the 737 characteristics the aircraft would have breached the flutter boundary without both a pilot and the equivalent of full manual nose down trim. However I speculate that flutter onset within the boundary resulting from high g is possible, though unlikely: I have encountered no evidence either way as to whether g and flutter are related. (Incidentally, even had there been flutter, as was likely in the 737 experience, the debris recovered disclosed no sign of fatigue causing an attachment failure.
• As to 3., the likelihood appears low that the damage from the flaperon strike is incidental to the part flap separation; the two being a coincidence that is. Even so it is fair to question, as Ge Rijn has, whether from its appearance that impact would be sufficient to break the flap. He prefers water impact as the cause for both separations. Coming from another direction there also is a question as to whether aerodynamic forces on the flaperon at low airspeed after its separation under water impact would be sufficient to cause the flap break. If not, the coincidence case is strengthened though there are other questions such as the effect of the engine water wake on the flaperon.
So I do not see the flap internal and external damage discriminating conclusively between a ditching or a mid-air wing break. Neither does any of this of itself completely rule out a flaps down ditching, powered.
Summarising, separations mid-air in an unpiloted pitch-up remains a possible explanation of the part-flap damage as does a piloted ditching.
While the above fails to resolve whether or not there was a pilot, it does help exclude some other possibilities.
Hi,I approach the discussion as an ex private pilot, not as an academic, although I did work for the CSIRO before retirement. I have been guided towards the following assumptions through argument, experience and common sense.
1) The disappearance was not an accident but was carefully planned.
2) Something went wrong with the plan just beyond waypoint Mekar at 18.22.12 UTC.
3) The aircraft turned south about this time.
4) Also at this time the aircraft reverted to autopilot control and settled onto a constant southerly heading.
5) I am convinced that no pilot was in control or the cabin crew would have been alerted through lack of food requests and toilet breaks from the cockpit etc.
6) During the next 6 hours until fuel starvation the cabin crew would have eventually been able to break through to the cockpit, assuming that people in the cabin were still alive themselves.
I have plotted tracks onto the Inmarsat Ping Ring data for speeds of 500 and 480knts and found that there is very good correlation between speed, constant heading and distance between rings. The only anomaly was between the 5th and 6th ring where the distance was too short for the speed and heading. I put this down to the surmise that one engine shut down due to fuel starvation which in turn slowed the aircraft whilst maintaining height and heading.
The plots put the possible crash location in the region of 40degrees 14 minutes N and 83 degrees 40 minutes E
@ventus45
Previously, I posed a question to @NTSB (via Twitter) concerning SSFDR/SSCVR readout capability and how common that is among air accident investigation bodies. The answer was: “Most of our international counterparts have the capability to download a recorder of that type.” with an additional contribution from an IASA member: “if State conducting investigation doesn’t have adequate facilities for read out flight recorders the State typically uses facilities made available to it by other States”
Note that OVV (NL) requested UK-AAIB to download data from 9M-MRD’s CSMUs and MY-AAIB also used UK-AAIB to download data from the CSMU recovered from a high profile helicopter accident (9M-IGB) that occured 4 Apr 2015. In the case of Egyptair MS804, the Egyptian lead investigation team used BEA to download the CSMU data.
NTSB, ATSB & UK-AAIB all have accredited representatives appointed to the Malaysian investigation. Malaysia is unlikely to ‘go it alone’, they’d be foolhardy to do so. If you wish to campaign, now is the time to demand transparency for the future procedures, not whinge after the event.
@Graham
Your end point is 40 South right?
I agree something happened after Arc5 (I feel major descent/slow down) so I feel approximate Arc2 to Arc5 is the constant level flight, and Arc2 is a stretch maybe Arc3 to Arc5 is the constant level flight. If we say Arc5 is the end of constant level flight, then that possibly brings back magnetic headings as a more favorable fit.
@Graham: Welcome to the discussion.
In the months following the disappearance, a number of us performed fairly elaborate path reconstructions using assumptions similar to yours, but perhaps a bit more sophisticated. For instance, speeds based on thrust modes such as constant Mach number, ECON, and LRC, and derived ground speeds based on the prevailing atmospheric temperatures and winds. As for a turn at 18:22, that is a bit too early based on the BFO and BTO sequences at 18:25-18:28, which suggest a northwesterly path in this time interval, and therefore an impact site along the 7th arc that is further north than you predict.
At this point, we have to include in our thinking the area that was searched without finding the plane, the timing and location of debris that has been found in Eastern Africa, and the fact that no debris has been found in West Australia. This evidence suggests that the impact site was north, not south, of the area that was searched.
@David
This is the issue I was objecting to strongly to @Victor and others in the previous topic.
The danger of only going for one assumption/conviction: a continuing high speed (uncontrolled) descent after 00:19:37 and consequently a high speed dive impact.
The opportunity and willingness of Ocean Infinity taking up this huge challenge is ofcourse great. If they succeed they’ll settle their name once and for all globaly. But if the fail…
I guess (and hope) they will do their homework very well and avoid the ‘mistakes’ previously made based mainly on a unpiloted flight and high speed crash after FMT. There is just too much debris-evidence and other circumstancial evidence that speaks loud against this scenario.
Also I hope they will look very critical to CSIRO’s 35S high probability area. It just doesn’t fit the ‘Roy-piece’ (and other pieces in between) and the total lack of debris found in Australia. The crash-site has to be more up North.
Then before they even start they would need full detailed forensic reports on the debris or do it themselves.
If they cann’t know the plane crashed in a high speed dive or a ditch-like impact it’s futile to start a search imo.
Debris fields would be totally different. The difference between maybe a million parts scattered around a huge seafloor or an almost intact hull in one specific place.
And the width of the search area would be crucial also in this regard ofcourse. If there was somekind of (controlled) glide involved (which I’m sure off, controlled or not, although controlled is the most logic imo rerarding all ‘evidence’ till now), the search area should be expanded according the maximum gliding ranges possible after 00:19:37.
And I hope they also take possible (Captain) motives into account like me and several others have put forward; a deliberate plan to take the plane down in a deep trench just under Broken Ridge.
If Ocean Infinity takes all this into account before they start I wish them all the best. If they decide to go by CSIRO’s latest predictions and a high speed (unpiloted) dive impact scenario also I tell them now they will fail also.
It has always seemed to me that the ping timings around the FTS and the possible paths which could have been flown after that, constrain the endpoint within limits. Does the surface search at 30S coincide with the original Inmarsat hot-spot or was that a little further north? Am I right that the northerly point of the atsb coordinated search which has been conducted is at about 33S? My own inexpert thoughts about the possibilities have always drawn me to a point frustratingly in between the surface search area and the northerly point of the deep sea investigation and it is this area between 30 and 33S which now needs to be searched. I’m not sure how much ground a private search might be able to cover and I understand that budgets must be limited. I’ve got my fingers crossed.
@David: Based on your comment, I skimmed some of the comments of others on that blog regarding terminal speeds and flutter. There were some statements about aeroelastics, aerodynamics, and design criteria that are not true, and should have been challenged. (They certainly would have been challenged on this blog.) Perhaps those statements were challenged and I missed it, because once I saw the discussion was moving in a direction based on false statements, I didn’t have the patience to read every comment carefully, nor do I think it is productive to repeat that discussion here. Whether or not flutter-induced failure of the flaperon occurred, I question the belief that flutter would have only occurred with a nose down command or a high-g pitch up.
If CSIRO and AMSA provide evidence that suggests it was nearly impossible for the aerial search to have missed a debris field on the surface north of 32S, then we have to consider flight that ended beyond the distance from the 7th arc that was scanned. That makes the possibility of an extended glide more likely. I have always been attracted to the simple path BEDAX-SouthPole because it fits the BTO and BFO with the autothrottle (and perhaps VNAV using ECON or LRC), and it can be flown in LNAV mode between just two waypoints. That path would cross the arc at 34.2S latitude. I abandoned this possibility after Phoenix scanned this part of the arc without finding the wreckage. However, if we are going to consider impact sites beyond what was previously scanned, I think this possibility is back in play.
@Victor Iannello: “There were some statements about aeroelastics, aerodynamics, and design criteria that are not true, and should have been challenged.”
Why didn’t you challenge those ‘false statements’?
@VictotI
On your remark: : ‘Whether or not flutter-induced failure of the flaperon occurred, I question the belief that flutter would have only occurred with a nose down command or a high-g pitch up.’
What other kind of attitude or circumstances you seem to think of could have induced flutter?
Since the discussion about flutter continues, I want to re-emphasize a point I have made many times since July 30, 2015, but one often ignored. First, a brief review of the background.
On July 29, 2015, we learned that the flaperon was found on Reunion Island. The next day, I published a short paper in which I suggested:
The trailing edge damage … could conceivably be the result of two possibilities:
1. Separation of the trailing edge due to contacting the water with the Flaperon in a down position, consistent with slow flight configuration for landing, or banking at the time of impact, or
2. Separation of the trailing edge due to high speed flutter at some unknown altitude above the ocean, followed within seconds by separation to the Flaperon from the wing, both prior to the main aircraft impact.
Since making that statement, ATSB and most independent investigators have concluded, as I did on July 30, 2015, that #1 above did not happen. For the reasons given in my paper, I felt in-flight separation was much more likely, and suggested that flutter may have been a contributing factor. I also listed a few other possible contributing factors that could have led to the in-flight separation. But critics of the in-flight separation theory insist on focusing on whether flutter was possible, rather than accepting the fact that in-flight separation was likely, regardless of the precise mechanism that caused it.
My suggestion now is that we stop debating whether flutter did or did not contribute to the in-flight separation of the flaperon. It really doesn’t matter. It is well documented (e.g., Flt 006) that large and small pieces of aircraft can and do separate in-flight when the speed and/or G forces exceed the normal envelope. That is all that is relevant here. The evidence strongly suggests that the flaperon and right flap segment separated in flight, regardless of the cause details. That means the flight ended close to the 7th arc, and that is what is really important going forward now.
@Gysbreght: I didn’t challenge the statements for lots of reasons. For one, I didn’t see them at the time they were proposed. Another reason is there are few places on the internet where I choose to participate. For a number of months, this blog has been my primary focus.
@ALSM
I a curious to know if you still feel inside Arc7 is possible (eg; based on the sea level calculation of Arc7 location)? At one time you pointed that out I am thinking.
Tbill: Yes, of course it is possible. The plane was probably already turning left at the time of the 7th arc, and might have been east or even northbound at that instant. In simulations, the plane typically made 2-3 360 turns before impact. So impact could have been on either side of the 7th arc.
@Victor. About the JW discussion you indicate, “… nor do I think it is productive to repeat that discussion here”. I take it that your reservations are no longer germane?
My aim in looking into the flap damage, being informed by the Silk Air analysis, was just to see what that meant about the possibility of there being a glide at end-of-flight
If we could eliminate a pilot possibility using debris damage analysis that would remove this uncertainty and it might do more than that. While it is understandable that the focus of the search would have priority over search width, the focus appears to be settled around CSIRO advice. Yet there is no sign of a comprehensive damage analysis, which of course should include the flaperon. Maybe the Malaysians are at it silently? (rhetorical!)
@ALSM. You and others have come to the conclusion that there was no ditching, “with the Flaperon in a down position”. However that leaves open a ditching with it in the neutral position though the ATSB concluded the flaperon separated from that.
You say the only other alternative flaperon separation explanation to the ruled out flaperon-down ditching would be following….., “Separation of the trailing edge due to high speed flutter”. I have posted an analysis tentatively showing the flaperon would rotate immediately after losing the trailing edge, for any reason. In separating in consequent overload, having rotated from the neutral, that again would be inconsistent with the ATSB conclusion above, leaving no explanation at all. Putting my analysis aside though and assuming that the Silk Air 737 experience is relevant to the 777, being of like configuration, MH370 would exceed its flutter boundary only with a pilot active.
“It is well documented (e.g., Flt 006) that large and small pieces of aircraft can and do separate in-flight when the speed and/or G forces exceed the normal envelope.” The pieces separating outside the envelope in both China Airways flight 006 and Silk Air flight 185 were flight controls such as ailerons and elevators (and in the Silk Air case, parts of the horizontal tail, presumably at a divergent speed/Mach or stimulated by elevators flutter), not lifting surfaces like the flaperon and flaps.
As to susceptibility to overload without flutter, would you not expect the flaperon and flaps to be designed to resist high cantilever loads in normal flight when fully extended? If so, the structure and attachments would require much higher strength than control surfaces. That is why I would expect them to be much more robust in resisting overload, to the point that the wing would fail before them when in neutral/retracted positions.
“The evidence strongly suggests that the flaperon and right flap segment separated in flight, regardless of the cause details.”
I am unsure that the evidence is so strong. If you mean the simulations, they assumed there was no pilot and in some cases they went beyond the simulator data base.
I would have expected Boeing to have advised the ATSB comprehensively on all this. If there is a persuasive case for saying that the flaperon and flap could only have separated from flutter or high g, would that not have have been apparent long since? Likewise were a long glide ruled out, would not the ATSB have made that clear?
“…. the flight ended close to the 7th arc, and that is what is really important going forward now.” Yes, concentrate on the main game. But do so without lifting hopes falsely, which has been a tendency. This started with Victor’s observation to you, “We need to also set realistic expectations about the probability for success of any one area, which has not been done in the past”.
@David
Regarding the flap, have you any thoughts on the failure mode of the flap track / pivot fixture, which seems to have gone “missing” in all the recent photos and discussion.
@David
Think you made a clear summary of the arguments on the possible reasons against flutter/in flight seperation for failure and damage regarding the flaperon and outboard flap section.
Would like to add again it’s not only the flaperon and outboard flap section that are very hard to explain this way.
There are also the left and right wing flaperon closing panels, the left outboard flap trailing edge piece, the right wing aileron trailing edge piece, the left and right wing flap fairing pieces and the nose gear door piece.
All seperated in flight due to flutter and/or other forces? While in Silk Air 737 and ChinaAir 747 none of those pieces seperated in flight during very high dive speeds and/or tremendous pull-out loads (both piloted)?
Why keep holding on so one-sighted to this explanation when a ditch-like low AoA, relatively low speed, ~level impact on the water surface could explain the kind of found debris, their damage, failures and seperations much easier?
I repaet again; the danger with this conviction is it excludes areas not that close to the 7th arc.
And I rather see Ocean Infinity not make this same mistake again.
@Ventus45
While I was writing already I like to state my view on your question to @David also. I’m sure @David will give his opinion also (I hope so anyway).
I think it’s an important issue not well explained in the ATSB-report on the outboard flap section imo (among other damage issues).
The ATSB-report mentions a deep dent in the middle of a stiffener under this rail-track on the underside of the flap (see report-photos). They regard this as evidence the outboard flap must have been retracted.
The stiffener above the rail-track also shows some damge but not in the middle and less severe.
I think the sequence must have been something like this:
The outboard flap was hit by a sudden (series) of great impact force(s) on the underside. This force(s) forced the flap to move violently upwards causing the track hitting the underside stiffener with great force causing the deep dent in the middle of the stiffener.
Which in sequence forced the flap track/pivot fixture to break off leaving the the rail-track moving free for a while causing damage to the upper-stiffener and its surroundings.
Shortly after was pulled through the leading edge completely with its flap track/pivot fixture when the flap section seperated from the plane.
The only (series of) forces I can think of (again) are water forces hitting the underside of the flap during a ditch-like entry into the water surface.
@Ge Rijn
“I think it’s an important issue not well explained in the ATSB-report on the outboard flap section imo (among other damage issues).”
Agree, that’s why I raised it again. As a major “metal” component, the metalurgy analysis of it’s fracture (which is a well known science, and could be critically peer reviewed,by many qualified people – if it is ever produced) would be telling. It is disconcerting that there has been no official mention of anything concerning that component, which, my suspicious mind, finds very suspicious.
Thank you for your insights on the matter. We await David’s reply.
@Ventus45
To me it’s a bit suspicious the ATSB-report on the outboard flap section only mentions in more detail the damage that supports the assumption the outboard flap was retracted and thus it supports the pre-assumptions their search effort was mainly based on: an unpiloted high speed dive near the 7th arc. Everything else is left out. While imo their are so many clear indications on that flap section (and many other parts) that indicate it could not have been a high speed dive impact.
I’m sure willing to believe the outboard flap was retracted on seperation with their explanation but leaving all other damage unexplained/not published and thus making the public believe only the conclusions their search was based on are valid, sure loads them with the suspicion of confirmation-biased research and covering up.
Their assumptions failed. They did not find the plane with those.
I hope our suspicion is not well-placed based on reality.
But still the detailed forensic reports on debris are not available.
@Ge Rijn, Ventus45
Everything else is left out.
Yeah, ATSB’s report didn’t even mention black holes & aliens. Whooda thunk they’d be so remiss?
¯\_(ツ)_/¯
@Don
Love the “birdie”, but sarcasm aside, I think you would be ill advised to be so trusting of the ATSB, and being so dismissive of those of us who aren’t, simply isn’t going to be productive.
The ATSB has a well documented track record of not mentioning many things relevant to an investigation. Quite obviously you are not familiar with the case of the Westwind ditching off Norfolk Island. I most strongly recomend that you do some research on the matter.
I appreciate that you are not a “local”, and quite naturally I suppose, are prepared to take the ATSB’s offerings “at face value”, ie, as, shall we say, ” wholesome”.
I am not going to labour the point, but those of us who are “locals”, do not. We have long experience of many sub-standard reports from the ATSB, one in particular, that is still “outstanding”, from 2009. That is eight years and counting Don.
I most respectfully suggest, that you would be well advised, to download and study this REPORT from the Australian Senate, and digest the misgivings contained therein.
Some other relevant links.
https://www.crikey.com.au/2014/12/05/pel-air-crash-investigation-was-a-debacle-from-go-to-whoa/
http://australianaviation.com.au/2014/12/atsb-to-reopen-pel-air-ditching-investigation/
http://vocasupport.com/senate-inquiries/pelair-norfolk-island/final-report/
https://www.atsb.gov.au/publications/investigation_reports/2009/aair/ao-2009-072/
Oh, I see that Victor had “Yellow Carded” me.
Well, I suppose I should take that as a compliment – perhaps ?
Returning to the “issue” of “investigative probity”, and just as a “by the way”, with regard to the then ATSB Chief Commissioner’s decision “not to recover” the CVR and FDR from the Westwind, I draw your attention to paragraphs 3.53 to 3.63 inclusive (in the Senate Report).
The “current” stae of play. https://www.youtube.com/watch?v=I0_qAUNo2pA It is quite illuminating.
@ventus45: If you submit a comment with many links, it goes into a queue that requires my approval. I did not “Yellow Card” you.
@Victor.
OK, I jumped to conclusions. I had forgotten about the three (was it) maximum link rule.
@Don
It has taken me a while to find it again, but I feel it has been necessay to do so, for your “backgrounding”, (and perhaps for others here as well), just so that you can all get a “feel” for how things are done, down here, in these southern latitudes, in the air accident investigation business.
Further to the Senate Report (previously referenced), here https://www.youtube.com/watch?v=4r8nxCwY7rg is the official video of the Senate Committee hearing, in which the then (now retired) chief Commissioner of the ATSB, Mr Martin Dolan explained, to Senator David Fawcett, why “he” decided NOT TO RECOVER the recorders from the Westwind, and where “he” was justifying “his” decision not to re-open the investigation.
(Note: under the Australian Transport Safety Investigation Act 2003, https://www.legislation.gov.au/Series/C2004A01102 such decisions are “his sole perogative”.)
If you still think that the ATSB is as white as the driven snow, I don’t think there is much point in continuing this discussion.
Perhaps we should wait, until the second report (all 450 pages of it, according to Commissioner (former Qantas Chief Pilot Captain Manning)) is released, due, we are told, in a matter of single digit weeks from now, by the end of September 2017 – he said. We shall see.
–
And, as if not enough controversy exists already (and I have not even got into the unholy relationship between CASA and the ATSB during the Westwind Ditching Investigation) the PelAir saga contimues. This from last night on the ABC. https://youtu.be/3QLONuGrJGc
@Don Thompson
With ‘everything else is left out’ I was imo clearly only pointing to a lot of other damage details on the outboard flap section.
The one @ventus45 mentioned but also on the big hinge, the missing trailing edge pieces, the leading edge damage, the (many) cracks, tension or compression induced. Nothing on those is explained or even mentioned in the report.
There is much more to the outboard flap section then only the damaged stiffeners and the dent in the seal pan supposed to be caused by the flaperons trailing edge hitting the outboard flap there (?).
Only those few things are mentioned that can support the assumptions their search was mainly based on; a high speed unpiloted impact.
This reporting can be accidental but it makes me wonder.
A much more detailed forensic report is required on the outboard flap.
And on the other debris.
I’ll see what they will publish end of September.
And I hope France will also free their forensic damage analysis on the flaperon.
@Ventus45. You will see there is a bottom link attaching the auxiliary support track (using ATSB nomenclature) to the wing. That braces the track against up and down rotation. Observe also that there has been a strike by the free end of the track on the stiffener above it, which Ge Rijn mentioned. Just looking at the ATSB diagram and how that strike came to be without skin damage further forward, that would be explained best I believe by the brace breaking in tension, the track free end rising and striking the stiffener. Most likely IMO that would happen as the flaperon hit the flap inboard end, driving that upwards.
What the ATSB terms the track’s ‘carriage assembly’ would have been torn out by stops at the track free end as that withdrew on rearward separation of this part of the flap; that is if it had not failed earlier while forcing the most damaging strike(s) on the stiffener below and to the outboard side.
“As a major “metal” component, the metallurgy analysis of it’s fracture (which is a well known science, and could be critically peer reviewed,by many qualified people.” Neither the carriage assembly nor track have been recovered. It is the sort of evidence that finding and recovering wreckage from the bottom could reveal, amongst so much more and over and above that from voice and data recorders. As to examination of the fracture where the carriage assembly had been mounted, maybe the direction in which that was torn out would help but corrosion to that rib might well have consumed the evidence.
You said to Ge Rijn, about lack of information from the ATSB, “I hope our suspicion is not well-placed based on reality”. I think the ATSB was bound to debunk a view expressed publicly by experienced pilots and others that the aircraft had been ditched, powered, that is if there was persuasive evidence that was unlikely. Likewise it would be bound to disclose any evidence to the contrary. The deduction from the flap and flaperon collision supported the no-flaps-deployed ditching case and they would be remiss not to bring that to public notice. There may be no other relevant deduction about pilot or not that it can draw.
@Ge Rijn. Thank you. I forgot to add a third contributor to the Silk Air 737 breaching the flutter boundary was engine power.
Yes the separation fractures of the flaperon closing panels in particular are relevant to the right flaperon’s separation. We have tossed this around before and I think it is hard to say how they were forced up with any conviction. The symmetry is striking. Also, while they were discovered only two weeks apart, the distance then separating them was considerable. I am at a loss to understand why the CSIRO apparently has not been funded by the Australian Government to do more drift analysis of real articles or realistic replicas, particularly those which are anomalous. Surely the most recent flaperon experimentation illustrates what can be gained.
Your enthusiasm for a ditching has been evident for some time but the evidence to me is not as powerful as to you. I follow what you mean about the wing debris evidence but for my part other debris tends to contradict that.
As to the assessment of the pros and cons for a glide the ATSB has access to expertise, experience and some items at least so should be in a a good position to draw conclusions. One can only hope they have enough information on items held by others, plus access to a 777 as needed. I see no grounds to doubt their integrity or to suppose bias, deliberate or otherwise.
Earlier I saw this general topic as relevant to search probabilities but do not think exploring it further here at this stage will be of any more benefit than with those at JW.
“And I rather see Ocean Infinity not make this same mistake again”. You say this in the context of search width. That is a subset of overall probabilities and I wonder what measure OI have of the likelihood of success of the ATSB/CSIRO proposed search, the area further north; plus the effect of the possibility of a glide, even if low?
Ge Rijn. Last line please, “…even if of low probability”.
@David
Thanks. I generally agree. I like to specify that I almost always speak of a ‘ditch-like impact’. Although I believe a controlled ditching after the pull-out of the 0:19 steep descent is the most probable, I can also imagine a uncontrolled descent with low bank angel (or level) with phugoids ending with the plane flairing out on the surface after it pulled out of the bottom of its final phugoid. Or a AF447 kind of impact. Something like that.
It’s in essence the high speed dive impact I regard impossible now.
We need more information that’s for sure but meanwhile it’s usefull imo to keep discussing this issues among others at least to keep the pressure on.
If we had all the information in time, there would have been no reason to discuss a lot at all to start with.
@GeRijn:
I notice that you accept the “0:19 steep descent” — perhaps you have for some time, but I haven’t noticed. Once this is credited, doesn’t this mean that impact was pretty close to 7th arc, and certainly not on the order of 50km or more? I think you [and others] have previously been arguing the latter.
@Ikr
Yes you are right I accepted the ‘0:19 steep descent’ lately.
To me this doesn’t mean though the plane must be within 50km of the 7th arc.
I think it’s quite possible the steep descent (8 seconds snapshot between 0:19:29 an 0:19:37) ended rather soon after 0:19:37 at around 20.000ft or so after a pull-out which could have left the plane another ~50 miles to glide to the surface.
@Ge Rijn
I like the alternate option of starting the descent at lower altitude say FL100, and then you can pull out but you are probably closer to the Arc7.
@Ge Rijn@All
There simply does not exist a scenario aside from an unplanned for event in which the airplane is not under pilot control until impact. Whether or not the PIC pulled out of the intentional dive the plane was put into is crucial to making a determination of possible distance from the 7th arc.
IMVHO, the LACK of debris, both landfall debris and unspotted debris (from air searches, though perhaps in locations where debris would not exist) lean heavily in favor of a controlled ditching. This is reenforced all the more so by the condition of the debris. If a high speed, nose down impact can effectively be all but ruled out…then we are left with one and only one scenario. Glide. And it seems bloody obvious to me that the fuselage is somewhere on the sea floor, largely intact.
This then brings us to looking at what the objectives of PIC would have been? Precisely, what he hoped to accomplish and why he would decide on a glide and controlled ditching as the optimal course of action?
I suspect one reason(the main reason) for the glide was the allure of it. There is something to be said for spending those last precious minutes of ones life gliding into the remoteness of the SIO at daybreak. I can’t imagine what or how the PIC was feeling during these last minutes, particularly in light of the events that transpired over the past 7 hours, but am quite confident that he would not have cheated and deprived himself of this time, and of the sensation of gliding down into the abyss, putting yourself to rest. Vastly understating here, but what a surreal 20 minutes (or however long)!
It also stands to reason, as I’ve said ad nauseam, that he would have a very specific target (and location) in mind. This would be entirely dependent on exactly what the objective was, and how the PIC prioritized the many different conditions and situations that would best enable him to accomplish said objectives.
For instance, did the PIC prioritize difficult underwater terrain (trenches, fissures, mountains, ridges) over sheer sea depth? Was there a location where both these criteria satisfied him?
Did he instead prefer a location more symbolic and meaningful and metaphorical, perhaps giving the above mentioned criteria less consideration as he was satisfied that the conditions found at his place of rest would be adequate?
There are many interesting (from my POV) avenues of inquiry worth digging into regarding the above. The PIC has left us with ample and fertile material from which quite a bit of insight into his way of thinking and even state of mind can be gleaned. It’s my belief that he has told us cryptically exactly where it is this aircraft lies.
This search may be as invaluable as the physical search in the SIO, but many here seem unconvinced. I haven’t been able to put all the clues together, yet. But he’s left posterity everything needed to discover the whereabouts of MH370…he was cold-blooded during those hours, but he was not a monster.
He would have considered the NOK. Contemplate that.
@TBill
10.000ft or 20.000ft I think there’s no way of knowing at which altitude this pull-out took place (IF this took place) but in the light of a new search effort I think it would be wise to establish a maximum altitude of a possible pull-out and with that a maximum glide-width.
@Donald
Interesting you mention this possibility of a symbolic location.
I mentioned once the possibility of ‘Broken Ridge’ being a metaphore of a ‘broken backbone’ (which he had suffered in the past during a paraglide accident). And a ‘broken back’ can well serve as a metaphore of a ‘broken spirit’ too.
@Donald
Ruminating further on your;
‘He would have considered the NOK. Contemplate that.’
Broken Ridge as a metaphore of a ‘broken back/broken spirit’ could even have served him as a kind of excusse to the world and the NOK reflecting his delusional state of mind and how he felt at the time in the case it ever came out he was the culprit.
This is all not ‘scientific’ and beyond proof like numbers and figures but I agree with you it is essential to also take psychology into account.
After all we know psychology and delusions played the major role in some horrific plane-crashes.
@Victor
Remind me your original favorite flight path that you thought had potential until the aircraft was not found…I think was around 35S end point. What did the overall path look like (loiter/heading etc)?
@Donald
“There simply does not exist a scenario aside from an unplanned for event in which the airplane is not under pilot control until impact”
Such scenarios do exist and have been discussed in various places but they have been largely discounted. I think it is more accurate to say that it is not necessary for anyone to have been alive on the aircraft at the time of the final dive into the ocean. The endpoints being discussed could have been achieved by the on-board systems acting alone from about 18:40.
My point is that although someone may have been alive at the endpoint, it is not necessary. I don’t think we have evidence to say one way or the other.
@TBill: My favorite “path with a loiter” was BEDAX-SouthPole, which can be flown in LNAV mode, follows a constant longitude along a track of 180°T, and crosses the 7th arc at 34.2S latitude. That was before GO Phoenix searched that latitude near the 7th arc and come up empty, and before any debris was recovered in East Africa. Any prediction of the impact site is only as good as the assumptions that were used to derive that location.
@Ulric
They really don’t exist. If you eliminate an unplanned for event occurring during a deliberate diversion, and also effectively discount all accident scenarios (which I am 100% comfortable and confident in doing), you are only left with two possibilities.
1) Pilot control until impact or very near impact (I suppose g forces during an intentional, high speed dive could cause LOC, but this a moot point. I mention it only to be precise).
2) That the PIC decided to take his own life by other means (hypoxia, lethal ingestion…pick your poison) at some point after the FMT and before fuel exhaustion/EOF. I.e. intentional ‘ghost’ flight.
IMO #1 is supported by the following: The PIC’s sim data (which supports intentionality of destination), the sparseness and paucity of the debris heretofore discovered (which IMO strongly supports intact hull/fuselage), the condition of the debris (which IMO argues strongly against uncontrolled, high or medium-high energy impact), and, lastly, the pre-meditation and planning that is plain to see (if one cares to look). This last point is an important one.
It’s just not in any way believable, given the nature (an exercise of absolute control) of the act committed and the personality of the individual committing said act, that this act would not be seen all the way through and micro-managed until control was LITERALLY NO LONGER POSSIBLE. The control aspect is inherent in the nature of the act itself, and was by all accounts very much one of the more remarkable personality traits of the individual committing this final action. Killing oneself after 18:40 and leaving the next 6 hours or so up to on-board systems to finish the TASK is just not plausible from any angle. IMO this scenario of intentional ghost flight is rather preposterous. It would be wise to eliminate this from all consideration as it would help to further winnow down possible EOF scenarios.
It’s a really quite ridiculous and short-sighted scenario, tbh. I don’t understand why it continues to have any real purchase other than propping up some peoples preferred narratives and agendas? This is my strong but humble opinion. Maybe people just haven’t given enough deep thought to the absurdity of the PIC killing himself prior to EOF/fuel exhaustion? IDK.
If someone would like to put forward a scenario in which the PIC deliberately takes his own life post FMT and prior to EOF, I’m all ears. I think the best reasons one can dream up are the PIC’s ability to have a relatively less painful death (by the manner of his choosing), and I suppose, the argument that the emotional of continue to fly with 238 deceased behind the door would not be something he could endure.
Both reasons fall flat on there faces.
So we are (once again, amazing) left with either an unplanned for event (nope), an accident (no way in hell), or PIC in total control until impact.
I fail to see how this is not the widely accepted assumption!
@Victor
I like that South Pole path a lot. I think it is almost equivalent to my proposed ISBIX 180 CTH path, so you had it 3 years ago. But I am trying to think of ways it got inside Arc7 by starting descent at 22:50ish. You are thinking maybe glided outside Arc7.
@TBill: I think the first step is to determine if the impact site could have been further north. The ATSB seems to believe that the debris field would have been detected by the air search. I welcome more information on the effectiveness and thoroughness of that search.
Some (drink induced?) psycho [case: Z did it]: I think everybody here took a look at Z’ videos about appliance repairs. But it has been said that Z also made videos about his job. Are they in public domain? Has anybody here seen them?
Those videos could inform about Z knowledge of 9M-MRO communication systems: what did Z feel when the satphone rang at 18:39? Could Z feared (erroneously): “they” know (or “they” could know) where I am because the system have to know that to make the call? (like many people do know that for cellphones). And so the left turn? And again at 23:14? If Z feared that, he could have faked a dive after flame-out at 00:19, then return the plane “dark” like it was before 18:22 and sank it far from there.
If the straight flight from the FMT to 7th arc was to mimic a ghost flight (everybody dead > reason “unknown” > nobody could be “indicted”), the places where the plane is not are:
– at flame-out distance of 18:22 (or 18:02),
– and further at maximum glide after the flame-out,
because Z could have thought that those places would have to be search immediatly and even after a ditching some parts of the plane would remains on the sea surface. Then, he took the plane elsewhere: ~60 miles beyond the 7th arc? Or north of it? I am afraid that there is many places where it could be… but it have to be in daylight (if Z killed himself earlier, he would have sent the plane all the way in the night).
Or not!
@PaxLambda
I have not heard anybody suggest other Z videos.
However, interesting question if the satcon calls might have motivated a pilot response of a course change or other maneuver. I am a broken record on this, but I do agree maybe Arc5 starting around 22:50 was the end of strictly level, straight flight.
@buyerninety,
On June 26, 2017 you asked:
“Did you progress further with your “trivial” reason for the FMT (of 180°), and did you come to this reason through reading my previous suggestions (and does the reason come about as a result of removal of waypoints?) ?
I apologize for the long delay. In part it was due to my relocation, in part because I did not make any major progress over the past half a year.
The trivial reason for the FMT I mentioned earlier is a trivial human mistake or a series of mistakes during the execution of so called “radar alerting maneuver”. This maneuver is aimed to alert radar stations when the navigation aids fail and/or when the communication means fail. It consists of the regularly repeated triangular patterns with 1 or 2 minute legs. In response, ground services are supposed to launch interceptors, which would establish visual contact with the aircraft in distress.
Respectively, my theory is based on the assumption of a simple counting mistake made by the PIC. If the number of turns is correct, then after the exit from the pattern the airplane continues on its original heading. But if the number of turns is wrong or exit direction is opposite to the required one, then the airplane changes its heading/track by either 60 or 120 degrees. Assuming the initial track of 289 degrees:
One extra leg mistake:
289 + 60 – 120 – 120 – 120 – 120 – 120 + 60 -> 169.
Exit turn of opposite direction mistake:
289 + 60 – 120 – 120 – 120 – 120 – 60 -> 169.
It could also be a combination of several mistakes of this kind. How could a pilot made such a mistake? My answer – due to the hypoxia. There are many videos in the internet on this topic. The ability to count is especially “impressive”.
It turned out that a combination of the radar alerting maneuver with descent, and with one trivial counting error can fit all the BTO and BFO data 18:25 – 19:41, except the abnormal BFO of 273 Hz. Interestingly, 2 errors of this kind result in a trajectory, which fits Kate’s (the sailoress) observation. See below some plots:
https://www.dropbox.com/s/h7g0754a83s4jpz/trajectory-v1.png?dl=0
https://www.dropbox.com/s/494mzxlovhvnnbx/trajectory-v2.png?dl=0
https://www.dropbox.com/s/1d5emi36jvadh7u/trajectory-v3.png?dl=0
In my opinion this theory explains the “loitering” and terminal heading/track of approximately 169 degrees after the FMT.
However, there is a challenging problem: descent to a lower FL implies more fuel burnt later. Respectively, fuel consumption must be incorporated into the flight path model.
I have to say this theory is also incompatible with the mainstream OXCO theory adopted by the IG and others to explain 18:25-18:40 BFOs.
@Andrew,
On June 25, 2017 you wrote:
“Consider what happens when the aircraft is on the ground with the ADIRU selected OFF. According to your theory, the SDU would be provided with position data from the GPS and other inertial data would be provided by the SAARU, correct? So SATCOM voice communications using the HGA should be possible on the ground when the ADIRU is selected OFF, correct? I can assure you, based on many years experience of operating the aircraft, that is NOT the case. SATCOM voice communications are NOT available when the aircraft is on the ground with the ADIRU selected OFF. Why?”
When the ADIRU is “OFF” on the ground is one thing; when the ADIRU fails in the air is another thing.
Just imagine a B777 flying over the ocean. The ADIRU fails. VHF is out of range. HF may not work. No communication is available. ACARS stops transmitting. ATC loses the airplane. The plane goes dark for several hours. What would its crew do? What would ATC do? These problems could be easily prevented/avoided if the SAARU and GPS are still functional.
@Don
With regard to the ATSB report (Mark-1) of the Westwind Ditching off Norfolk Island, the original (all 77 pages of it) is no longer available on the ATSB’s web site, but it can still be downloaded from here.
https://aviation-safety.net/database/record.php?id=20091118-0
https://reports.aviation-safety.net/2009/20091118-0_WW24_VH-NGA.pdf
I suggest you download it now, and keep a copy for comparison purposes, with the “new report”, when it is released.
Note that ATSB Commisioner (former Qantas Chief Pilot) Captain Cris Manning said in the Australian Senate:
(a) The new report (Mark-2) is 450 pages
(b) It is a different report.
(c) It is a “significant” report.
(d) It should be released by the end of next month (September 2017).
@Don
I forgot to mention this.
http://www.abc.net.au/reslib/201503/r1401912_20014986.pdf
@ventus45
An ATSB report of 450 pages must be ‘significant’. I expect from them everything gets explained and shown in detail about everything they have investigated and done. Including very detailed debris-damage-analysis (outboard flap section) and also on the bio-fauling and the barnacle(s) they received from France.
We all, and Ocean Infinity too I suppose, will await this report with great interest. And I’m sure the ATSB is fully aware it will be looked at and evaluated in every detail again by the IG and all independent searchers and researchers affected by this tragedy and mystery who won’t let go till this tragedy and mystery is solved.
And behalve of the NoK who’ll never find closure and some piece as long as they don’t know where their loved ones rest and why and what happened.
Noting it’s half a year now since the last two pieces of debris were found and reported. The big flap fairing piece and the right wing aileron piece. Both pieces are also near the ‘Roy-piece’.
All three pieces contradicting the CSIRO/Griffin conclusion about 35S in being too far south.
And also indicating again imo there was a quite limited debris-field from the start consisting mainly (23) of wing trailing edge/engine cowling,
H/V stabilyser/nose gear door pieces. With only three easy reqocnisable cabin parts (and one nearly intact, monitor mounting).
All parts you could expect seperating in a low AoA, ditch-like impact with partial break-up/breaching of the fuselage.
This is all that has been found after 3 1/2 years. This should be indicative too of a quite small debris field after the impact.
I keep advocating this for I would regret it not to have done so after a new search effort was started and would have failed again.
@ventus45
I’m aware of your fascination with the Pel-Air case. Thank you for the linkfest.
My ‘shrug’ was in response to the singular focus (tunnel vision?) some are giving certain debris items while ignoring the many, many small fragments of debris that have been recovered on shorelines but not documented by the Malaysia team: small fragments of flat GRP skin, honeycomb core, sheet; sheet material that is typical of cabin interior structures.
Such items, plus the acknowledged interior parts, are important indicators for the force of the ocean impact. The two French documentaries show finds of these small panel pieces, and also Paul Smithson recovered such a piece of the coastline of Tanzania. Paul’s experience mirrors that of those of the NoK group who visited Madagascar December last: these small fragments of GRP skin + honeycomb core panels seem to be abundant.
@Don Thompson
I think you are referring to me also after my previous comment so I’ll respond.
The small found panel-items you referre to could well be from MH370 but give no indication about the force of the impact beyond a ditch or crash landing.
Those panels are structuraly relativaly weak and break up also this way in a low speed crash landing. Look at Asiana 214.
A breach/partial break up of the hull during a ditch could have released those pieces.
@Don Thompson: The find by Paul Smithson is significant. He did what others are falsely claiming is impossible: Like Blaine Gibson, he decided to look for MH370 debris, and within a short period of time, he found a small item with a honeycomb core that looks like it is from an aircraft. I considered posting an article of his account, but I got pulled in other directions. In light of the continued attacks on Blaine, perhaps the circumstances surrounding Paul’s find should be made better known.
Ge Rijn wrote: “I expect from them everything gets explained and shown in detail about everything they have investigated and done. Including very detailed debris-damage-analysis (outboard flap section) and also on the bio-fauling [sic] and the barnacle(s) they received from France.”
All: Unfortunately, the ATSB report is not expected to contain any new information on the debris analysis. Hopefully, if the search is restarted, there will be some additional tests and analysis. In particular, additional tests on the flaperon (if the French cooperate) and the flap segment are potentially helpful. For example, ultrasound tests could answer questions about the dynamical forces that caused the shredded trailing edges. If further analysis answers the question about inflight separation, then the width of the search area could be minimized with confidence.
@ALSM
At last I agree with your less rigid opinion that leaves more room for something else then an in-flight seperation.
I would welcome conclusive proof of an in-flight seperation for sure.
It would make things a lot less complicated regarding the new search area.
The ATSB has not published their report yet. They still have time to add or remove content.
My goal was/is only to keep the pressure on.
Finally I agree with all you say to all.
And I’ll correct the phrase ‘bio fauling’ to ‘biofouling’ for those who did not understood what I was meaning.
I’m Dutch so English is not my native language.
Gladly @ALSM and others teach me how to improve my English on such details.
@All
I want to sound a note of caution here before the seemingly self-propagating drive to S35 and/or S30 passes its tipping point. Firstly, the ATSB have no real, genuine or altruistic interest in finding the plane. All they are really interested in is covering their asses. Their report on the RH outboard flap is ample evidence. They found the damage points to the flap being retracted at the time of impact, supporting the no pilot control after FE scenario, and therefore vindicates their search strategy. Phew, at least they don’t have to reassess their initial assumptions and consider the unthinkable notion of a conscious pilot deliberately gliding the plane as far as he could just to make it even more difficult to find. I don’t doubt for one minute that the flap was retracted at the time of impact, because a flap-down slow speed ditching into the remote SIO makes absolutely no sense. On the contrary, the damage more likely indicates a deliberate, nose-up belly flop designed to sink the plane as quickly as possible.
When the ATSB failed to find the plane at the southern end of the 7th arc, the area supported by the DSTG Bayesian analysis, their initial best shot, then they got CSIRO to do some creative work with their drift analysis. And they duly came up with the goods – they pointed the finger at S35, an amazing piece of good fortune because this was the very area the ATSB had been persuaded to cut short. So now all they have to do is promote the new 25,000sqkm search area, and save their reputations.
Now, the piloted glide scenario is rightly getting more traction, due to the debris now receiving more careful attention, but it could (more likely will in my view) turn out to be a major mistake if the focus remains firmly fixed on the area of the arc north of S38, at the expense of the area downrange of s38 itself.
I don’t like having to cast myself as the spectre at the feast, but I feel it my duty.
@Rob
You continue to ignore the lack of debris being found in WA.
@Don
“My ‘shrug’ was in response to the singular focus (tunnel vision?) some are giving certain debris items while ignoring the many, many small fragments of debris that have been recovered on shorelines but not documented by the Malaysia team: small fragments of flat GRP skin, honeycomb core, sheet; sheet material that is typical of cabin interior structures.”
Exactly. The statistics relative to the earlier debris finds strongly suggest that hundreds of pieces are still waiting to be found. Granted, many of them will not be suitable for attribution to 9M-MRO.
@Rob
Ofcourse you are obliged to your views and opinions and you should advocate them as long as you believe they must be right. Much makes sence to me as you know but just your holding on to 38S and beyond for three years now just doesn’t make sence to me. Asif nothing happened in between.
It’s completely clear by now the crash could not have happened south of ~35S regarding the latest (and earlier) drift analysis and the complete lack of found debris on Australian shores against all the debris found on African shores (and a lot more reasons).
I would rather like to see your often creative views spent including the latest research and insights.
I don’t mean this as devaluating at all (I mostly like/value your comments) but maybe have a try to concentrate on a different view also.
38S and beyond are definitely out of order I’m sure. South of 35S is allready quite clear off the record imo. It’s just under Broken Ridge they have to look imo.
Around ~32S in the trenches somewhere.
This fits everything. Lack of a (big) debris-field due to a deliberate ditching. The relatively very few items recovered after 3 1/2 years, the kind of ~90% items found (trailing edge/wing/control surface related), their damage, the inherant intent to cover all clear evidence up as good as possible (in a deep trench?) which succeeded till now. The sim-locations. The re-logon at 18:25. The six hour flight after till the break of day.
Much I can go along with you but definitely not past ~35S let alone 38S.
The MH370 families want to know why Malaysia has not accepted Ocean Infinity’s offer to search for a fee that is contingent upon success.
https://twitter.com/cryfortruth/status/895685965724999680
Without knowing the details of the offer, it is hard to assess whether the associated terms of the offer are reasonable. However, it would be unacceptable if rumors are true that there are no active negotiations.
Ge Rijn:
My opinion (on the flaperon) has not changed since July 30, 2015. I’ve never been “rigid” in my views. I’ve always felt the evidence supports the assumption that some pieces of 9M-MRO may have came off in flight, and the photos of the debris make it pretty clear separation in-flight was certainly possible for some pieces, if not likely. I have yet to hear any explanation for the lack of compression damage on the leading edge of the flaperon and flap segment, assuming it was still in place at the time of impact. OTOH, the lack of leading edge compression damage is exactly what we should expect for in-flight separation.
I would like to see more evidence because it is very important to the determination of the search width. Ultrasound testing is SOP for fiberglass and carbon fiber aircraft suspected of possible hidden damage (delamination, etc.).
For those more interested in NDT and ultrasound…here are a couple of links:
https://goo.gl/GVKRp4
https://goo.gl/cB3mPr
@Victor
“Without knowing the details of the offer, it is hard to assess whether the associated terms of the offer are reasonable. However, it would be unacceptable if rumors are true that there are no active negotiations.”
I think you are being a bit gullible. “Unacceptable” has no meaning in your statement above. Unacceptable has no actionable result. What are the people to whom the situation is deemed unacceptable going to do? The answer is nothing meaningful.
From the Malay perspective why sign up for a liability that has no associated benefit? Do you think everyone is a nice guy with a moral conscience like you? If I were in the Malay’s shoes I would not sign up for it either. It is reminiscent of watching a direct report struggling to find an answer to some extraneous problem or other. My question would always be “what will you do differently if you knew the answer?”. For the most part that question was a show stopper.
The Malays have no interest in finding the plane. Why should they pay for it?
@TBill
“I have not heard anybody suggest other Z videos.”
It was clearly showed in the French “Envoyé Spécial” documentary “MH370 : aller simple pour l’inconnu”.
From the time 00:19:11 to 00:20:30 there is an interview of Gerald Ramesh (described as an organizer of flight instruction at MAS) who speaks about “professionnal” videos made by Z. He shows an abstract of one of them on a tablet from time 00:19:57:
Z : Hi everybody, here is a YouTube video that I made.
Envoyé Spécial : That day, he explained to the budding pilots how to deal with a hydraulic system failure.
Z: This video will serve you to optimize the oil compression ratio, to reduce your power consumption.
Gerald Ramesh: When you have someone so passionate about his work, it’s really hard to believe that he did anything with his plane, that he voluntarily crashed at sea.
Translate by me, so be carefull! Victor gave a link to this video in English but I have not kept it. Times may differ a little between versions.
@Victor: If you have kept the link, thanks to give it again.
@Ge Rijn
“Look at Asiana 214.”
Seriously, have you?
The NTSB Structures Group Report, Attachment 2 (28 photographs) or Survival Factors Exhibit 6 (104 photographs), for example.
The interior of HL7742 did not experience the extent of destruction evident from 9M-MRO debris. While some HL7742 interior structures collapsed, the structures’ panels were not shattered.
HL7742’s port outboard flap detached with its drive arm and pivot link intact. All wing and horizontal stablsr closing panels appear in place.
HL7742’s landing was violent: all landing gear was detached, both engines, the complete empennage, AND the fuselage bounced, experiencing a flat 360º spin before finally settling on the ground.
Do try to realign that oft cited opinion with reality.
@DennisW: The NOK appear to be well-organized, and also have the moral authority and some ability to pressure the tripartite countries to re-start the search. Malaysia may or may not listen, but Najib does not have unlimited power, either. He is an elected official that needs to be sensitive to public sentiment in order for his party to win elections and to maintain civil order. We’ll see how this plays out.
As an aside, US Secretary of State Tillerson’s recent meeting with Najib was noteworthy. It signaled that despite the ongoing US FBI investigation of the 1MDB fund, Najib is still an important strategic US ally that can help restrain regional terrorism, Chinese expansionism, and North Korean aggression. I don’t think the MH370 search enters into those discussions.
@Dennis As I mentioned I taught mediation and negotiation in Shanghai for the past 8 years. Usually in Chinese negotiation if the offer is outside the range of the other party there won’t be a counteroffer. In this case there was no upper limit to the offer so there would be no counter offer. If a maximum amount was part of this Malaysia might respond. I know they can’t guarantee an upper limit so it comes down to which side is willing to take a chance.
@Trip
I have no idea what the offer actually was. My impression, which could be incorrect, was that it was for a fixed sum reward. A reward based on time and materials would be the similar to the previous search in terms of financial burn (less per searched area presumably). I don’t see how that could make any sense as a going in position.
@Victor
David Gallo’s remark in your link was interesting-
“I DO NOT like the idea of reward. It bothers me deeply. Our team was wholly dedicated to find AF447 as a humanitarian mission.”
@Victor
“I don’t think the MH370 search enters into those discussions.”
Almost certainly not. It would be considered small potatoes at that level.
I would not be surprised if MH370 was tracked on SBIRS, and that the information is classified.
@TBill: I think that David Gallo was reflexively reacting negatively to the concept of a reward for helping families in a tragedy. Based on his subsequent comments, I don’t think he views the concept of a success-based fee as bothersome.
@Oleksandr
RE: “Just imagine a B777 flying over the ocean. The ADIRU fails. VHF is out of range. HF may not work. No communication is available. ACARS stops transmitting. ATC loses the airplane. The plane goes dark for several hours. What would its crew do? What would ATC do? These problems could be easily prevented/avoided if the SAARU and GPS are still functional.”
Data link communication (ie CPDLC) is used in most oceanic areas and other remote regions. If CPDLC is being used, the aircraft will also establish HF contact with the ATC provider, to ensure there is a secondary means of communication. HF is normally available, except when the ionosphere is affected by high levels of sunspot activity. If the ADIRU fails, the data link should still be available via the low gain antenna. If the data link does fail, then the crew would attempt to communicate with ATC via HF. There are well established procedures in place to cater for the loss of communications if HF is also not available.
The suggestion that the SATCOM has some magical ability to use GPS data in the event of an airborne ADIRU failure (if that’s what you are suggesting), is wrong.
@Andrew: The position, track, and speed are required for pre-compensation of Doppler shift, even if the LGA is in use. With no ADIRU, I don’t think SATCOM would be available.
@Victor: Fair enough. The crew would then fall back on HF and if that doesn’t work the crew and ATC would follow their standard loss of communications procedures, including air-to-air VHF relay of position reports and clearances by other aircraft. Given the number of aircraft plying the skies and the fact that most of them follow defined oceanic tracks, it would be extremely unusual for an aircraft to lose ALL contact for more than an hour or so.
I thought Oleksandr flight path was interesting, but we know EK343 was coming up closely from behind so there was air traffic to consider. Interesting to consider if instead of an offset, the diversion from N571 was to a holding pattern off of N571.
@TBill
The radar alerting manoeuvre that Oleksandr mentioned is used by military aircraft to alert military radar controllers in the event of a radio communications failure. It is not a recognised ICAO procedure and is not normally used by civil aircraft.
@Don Thompson
On your remark:
‘Do try to realign that oft cited opinion with reality.’
Regarding pictures from Asiana 214 interior I did this long time ago by placing links on JW-blog.
I’ll post one of those links again.
Take a look at picture 28, 29, 30, 31 and 4:
http://www.nycaviation.com/photo-galleries/photos-asiana-214-crash-site/nggallery/page/2/image/asiana-214-crash-site-27
In picture 29 you can also see a missing back seat monitor mounting.
@Victor. Judging by the size of the USVs and looking at the shipboard system for their deployment and recovery, they may be suitable for limited open-ocean seas and winds. Precautionary recovery requirements might limit operating times and seasons. Securing and handling might impose other limitations and multiple recoveries would extend the precautionary time. Handling and securing inboard might impose other sea state limitations. Sea states also might limit communications to and from the AUVs below. I think too about USV refuelling and in what conditions they need recovery for that and for maintenance/repair.
Presumably that mother ship’s helicopter deck would be removed to improve seaworthiness, she being some days away from shelter.
Who knows how they have done their success probabilities but presumably they have high confidence in their business case, while knowing as they would of any limitations and lost time arising from the above search weather requirements and penalties and also the lengthy mother ship returns to the coast for logistics or anticipated weather. Included also in the business case though would be confidence in estimates of the area(s) they would need to cover and an intended search sequence, to minimise probable search length.
Perhaps they have a benefactor; or alternatively an insight/analysis superior to those current (eg where to start, ATSB/CSIRO area, further north, somewhere else?) as a basis for the chances of collecting the reward. Without either the gamble might need a very high mark up in the reward.
However, expanding on an earlier remark, the publicity they are getting now is risk free.
I am being a suspicious wet blanket I know.
Do you know how David Mearns would conduct the search if he could get a privately funded search going? I suppose his effort is on hold while the Ocean Infinity proposal is considered.
@David
“I am being a suspicious wet blanket I know.”
I am in the same boat for the same reasons. I really would like to see the search resumed by Ocean Infinity, but I don’t have a good sense for their pedigree or how their technology would fare in the conditions of the search area.
@Andrew,
You wrote “The suggestion that the SATCOM has some magical ability to use GPS data in the event of an airborne ADIRU failure (if that’s what you are suggesting), is wrong.”
Nothing magic. We know that time data originated from the GPS reaches the SDU via GP channel. Why can’t lon/lat data reach the SDU by the same channel? We know that SAARU data reaches AIMS. Why can’t it be passed to the SDU? I understand this is not explicitly specified in the document you refer. However, the absence of evidence is not the evidence of absence. What you state might be true, but it is hard to believe that the designers of B777 and SDU did not implement a simple programmatic check for reliability purpose: if ADIRU available then use ADIRU; else use SAARU+GPS. It is only programmatic issue what to include in a data package, and how to use it.
Re: “The crew would then fall back on HF and if that doesn’t work the crew and ATC would follow their standard loss of communications procedures, including air-to-air VHF relay of position reports and clearances by other aircraft.
What are these procedures? Imagine a plane 2,000 km away from the nearest shore. Out of VHF range. HF depends on weather conditions – may not work.
Re: “The radar alerting manoeuvre that Oleksandr mentioned is used by military aircraft to alert military radar controllers in the event of a radio communications failure. It is not a recognised ICAO procedure and is not normally used by civil aircraft.”
Well, one document which describes it is “LIGHT INFORMATION HANDBOOK” by the US Department of Defense, dated 6 JUL 2006. The procedure is “RADAR DISTRESS SIGNAL PROCEDURE FOR NATO OPERATIONAL AIR TRAFFIC”. However, there is another document “CANADA FLIGHT SUPPLEMENT / GPH 205”, effective 15 January 2009. Its “EMERGENCY COMMUNICATIONS PROCEDURES” chapter appears to be applicable to both civil and military planes. I relied on the latter in my modeling.
Either way, the keyword in your statement is “normal”. What is normal in MH370 case?
@TBill,
RE: “I thought Oleksandr flight path was interesting, but we know EK343 was coming up closely from behind so there was air traffic to consider. Interesting to consider if instead of an offset, the diversion from N571 was to a holding pattern off of N571.”
In either case EK343 was close, and it should have detected MH370 on its weather radar. Just a thought: holding pattern and descent of MH370 would shortly leave it behind EK343.
One thing I forgot to mention. Try to guess what the turn angle is in the ‘feature’ in the IR satellite image presented by Bobby U.? Approximately 120 deg…
In the B777 installation,the SDU does not receive any raw GPS data. Read the manual. It only receives INS position data via 429. In other aircraft, position data can be provided to the SDU by alternative means. But in the B777 installation, it uses INS data. All this is documented in the manual.
@Oleksandr
“In either case EK343 was close, and it should have detected MH370 on its weather radar. Just a thought: holding pattern and descent of MH370 would shortly leave it behind EK343.”
Maybe that was the strategy, but of course, we do not really know what the PIC was doing between 18:22 and 19:41-ish…maybe still some maneuvers ending around 19:41 or after. Seems to me, pick a spot for MH370 to be at 19:41 or thereabouts, and then it’s just making up scenarios for what might have happened before 19:41. But it’s instructive to brainstorm. It would be better to hear ATSB brainstorm path options, as that could give us a clue if they know something (eg; Singapore radar data) that we do not know.
@David: I’ve seen words from Ocean Infinity saying that for the proposed project, the “fee” is payable to Ocean Infinity only if the search is successful. Well, in the world of government contracting (at least in the US), a common type of contract is Cost-Plus-Fixed-Fee (CPFF), in which case incurred costs are billed progressively at the (fully burdened) rate, usually up to some limit, and a fee is collected upon completion. The price of the contract is the cost plus the fee, so the fee is the profit. If this is indeed the structure of the proposed agreement, then there would be substantial economic risk for Malaysia, as Ocean Infinity would be billing for incurred costs. If, on the other hand, all payments (cost and fee) are deferred until the plane is found, then Ocean Infinity would assume all of the economic risk. Without a better understanding of what was proposed, it’s hard to know how the economic risk is apportioned between Ocean Infinity and Malaysia.
@VictorI
The wording used by Ocean Infinity spokesman, Mark Antelme, seems to not imply a CPFF contract.
“The terms of the offer are confidential, but I can … confirm that Ocean Infinity have offered to take on the economic risk of a renewed search,” company spokesman Mark Antelme said in an email.
http://www.nydailynews.com/news/world/company-offers-hunt-malaysia-airlines-mh370-article-1.3401725
The only “economic risk” associated with a CPFF contract is opportunity cost – the loss of revenue and profit associated with doing something else instead. I suppose Ocean Infinity could be referring to that when they refer to “take on the risk”, but that would be misleading IMO.
@ALSM,
Re: “In the B777 installation,the SDU does not receive any raw GPS data. Read the manual. It only receives INS position data via 429. In other aircraft, position data can be provided to the SDU by alternative means. But in the B777 installation, it uses INS data. All this is documented in the manual.”
Can you point out that mysterious manual? Andrew shared some extracts, which were inconclusive in my opinion. Don promised some materials twice, but never did (or I missed them).
There are two separate channels, L & R, which supply INS data via the AIMS based on the diagrams shared by Andrew. The SAARU also supplies data to the AIMS, as well as to ADIRU’s ARINC-C FCA. I have not seen any documents stating that SAARU’s data cannot reach the SDU via the AIMS in the same way, especially if the ADIRU fails.
With regard to the GPS data. It was mentioned that time data is supplied from the GPS to the SDU via GP channel. The time is originally sourced from the GPS. Nothing was stated with regard to other data, which could be supplied to the SDU via GP channel.
What other aircrafts’ SDU receive GPS data, and why this simple feature is not implemented in B777?
@DennisW: Exactly. The economic risk of the CPFF contract is the opportunity cost of not collecting the fee (profit) if the project is terminated before completion, i.e., before the plane is found.
What leads me to believe this is possibly the arrangement is their use of the words “a fee” instead of “payment”. The word “fee” has a very specific meaning in project contracting. According to CNN Money:
The group [Ocean Infinity] said the company expects a “fee” for the search only if it is successful in finding the aircrafts wreckage.
Oleksandr,
Do you have a copy of the continental-train.pdf manual? If not, I put a copy of mine up here:
https://www.dropbox.com/s/2n2c9l6l11jcvp6/continental-train.pdf?dl=0
3328 pages. Supposedly there’s more, up to 6000 pages, which I don’t have.
This document provides a wealth of detailed information of what connects to what. Here’s the location of the interesting sections:
AIMS: pdf p. 247
PDS: pdf p. 363 (Primary Display System)
CMCS: pdf . 701 (Maintenance system)
Manuals: pdf p. 965
ACMS: pdf p. 1033 (Monitoring system)
Electrical: pdf p. 1079
FDR: pdf p. 1323
DCMF: pdf p. 1355
FMC: pdf p. 1429
TMCS: pdf p. 1549
PFCS: pdf p. 1621
AFDS: pdf p. 1639
ADIRS: pdf p. 1797
ATC systems: p. 2311
SATCOM: pdf p. 3221
Under SATCOM, it says:
=====================
AIMS Connections
The SATCOM system also connects with the airplane
information management system (AIMS) for these
functions:
– Data conversion gateway function (DCGF). The DCGF
changes inertial reference system data into ARINC
429 data for high gain antenna (HGA) beam
steering. The DCGF also supplies international
civil aviation organization (ICAO) addresses.
———-
Airplane Information Management System (AIMS)
AIMS sends this data to the SDU:
– Inertial Reference Data
===========================
Throughout the document, the distinction between Intertial Reference Data (ADIRU -presumably also SAARU) and GPS data is crisply maintained.
@VictorI
If Ocean Infinity is proposing a CPFF contract, it is a non-starter, IMO. That is less favorable than paying a fraction of the search cost with no “finder” fee which was the arrangement that was terminated.
Notes on AES antenna pointing data requirements here:
https://goo.gl/8WERFy
Andrew: I would like to see the diagrams referred to above by Oleksandr. Can you repost a like please?
sk999: Thanks for your post on same subject. The ADIRU, SAARU and GPS are all inputs to the AIMS. AIMS then supplies the required labels to the SDU via 100kb/s 429 bus using what ever data is available to compute the parameters (probably using a Kalman Filter).
Here is the full 6656 page Continental Manual:
https://goo.gl/KwsMZe
@sk999,
Thanks for this pdf; I did not have it. Now I have it.
Extract from Pdf p. 2185:
The general purpose (GP) data buses supply this data:
…
Latitude and longitude (from the FMCF)
…
Extract from Pdf p. 1446:
FMCF receives data from the ADIRU and SAARU.
Extract from Pdf p. 1448:
“The FMCFs use GPS altitude, position (LAT and LON), and velocity data with ADIRU and radio data to calculate present position and ground speed.”
My understanding is that GP bus supplies position and attitude data to various user system, including the SDU (GP 1 bus – see p. 3263). However, this data is mixed data from the ADIRU, SAARU and GPS, in contrast to the ‘pure’ inertial data supplied via INS bus. Hence, it appears GP bus may still provide position and attitude to the SDU when the ADIRU fails.
@DennisW: If multiple AUVs reduce the cost per square kilometer and the tripartite countries share the cost, a cost-reimbursable contract could still represent more favorable economics than what Fugro provided.
Despite the optimism expressed by CSIRO, based on the information that is publicly available, it would be very difficult for Ocean Infinity to realistically assess the probability of finding the plane. Either they have more information than we do, or they are misinformed about the chances for success, or the contract allows them to recover costs.
@alsm, sk999, et al
AIMS is only a platform, at the level of detail necessary to clarify Oleksandr’s misunderstandings one needs to be specific about the functions performed on AIMS, and the inputs/outputs relevant to those functions.
The ADIRS interfaces to many systems & functions over the L, R & C A629 busses (note, ADIRS not simply ADIRU), the MMRs interface to the FMCF via A429 to provide GPS position information used in IRS drift minimisation. The GPS derived clock data is a separate data distribution. The DCGF provides the position & attitude data to the SDU via redundant A429 busses.
There is no magic AIMS ‘crossbar’/’common backplane’ interconnecting its hosted functions that could be imagined to permit functions to share & arbitarily select data sources.
About as Weisian as it gets…
“Hence, it appears GP bus may still provide position and attitude to the SDU when the ADIRU fails.
@Don Thompson,
Can you be more specific?
Oleksandr,
Glad to help. Also, thanks to ALSM for the full document (and for the record, the stuff I was missing covers fuel systems, engines, landing gear, doors, etc – all good stuff to have when flying a plane).
You then go on and quote text from the sections on the Ground Proximity Warning System and Flight Management Control System as if somehow it is relevant to the Satellite Communication System. ??? Just because a lot of signals are being passed around doesn’t mean that every system sees every one.
@ALSM
RE: “I would like to see the diagrams referred to above by Oleksandr. Can you repost a like please?”
It’s the same diagram (SATCOM System -Interface Diagram) as the one on p.3263 of the Continental manual.
RE: “In other aircraft, position data can be provided to the SDU by alternative means.”
The Honeywell MCS-4200/7200 SATCOM systems are able to use GPS position data to position the antenna, depending on the set up. Do the older MCS-3000/6000 systems have the same capability?
Andrew:
Thanks for the reference.
The block diagram on Pg 3263 shows the AIMS-left bus going to the primary SDU 429 connector and the AIMS-right bus going to the secondary 429 connector. The same data is available via either the primary or secondary 429 bus.
The data required by the SDU in order to aim the HGA and calculate Doppler offset are:
Format: 2-wire high-speed ARINC 429 input
LABEL – WORD:
310 Latitude
311 Longitude
312 Ground Speed (optional)
314 Heading (True)
324 Pitch
325 Roll
361 Altitude (optional)
There is no “GPS connector” on the SDU. Only 429 bus connectors for “nav data” input. There is no way to connect (via hardwire) a GPS directly to the SDU.
MSC-4200/7200 (and 6000) systems do not use raw GPS position data. They use navigation information (all the labels above) calculated using a software routine hosted on AIMS. One of the sensors feeding the algorithm is the GPS. The output position information (parameters label 310 and 311) are calculated using the INS (integrated) position, corrected for long term gyro drift using GPS, plus airdata. If all INS data is lost, the algorithm could (theoretically) produce degraded 310 and 311 labels based on GPS data alone, but 324 and 325 can not be derived from GPS alone. Bottom line, the SDU can not and does not aim the HGA based on GPS alone.
@ALSM
How can you put ground speed in the optional category for calculating Doppler offset?
@ALSM
I wasn’t suggesting that the SDU could position the antenna using GPS data alone; my question was related to the generic Honeywell SATCOM system, not the system installed in the B777. I know the GPS does not supply the SDU with position data in the B777 and have been trying in vain to convince Oleksandr of that fact for some time.
Nevertheless, the Honeywell manual for the generic MCS-4200/7200 SATCOM system states the following:
“Standard interfaces between the MCS-4200/7200 avionics and the other aircraft avionics include the following:
…
– The IRS and GNSS (GPS), where installed, to supply the SDU with navigation coordinates for positioning the antenna platform.”
That statement seems to suggest the GPS can supply the MCS-4200/7200 system with position data in some installations, . Is that statement incorrect?
@Oleksandr
RE: “What are these procedures? Imagine a plane 2,000 km away from the nearest shore. Out of VHF range. HF depends on weather conditions – may not work.”
HF usually does work, despite your assertion to the contrary. If HF communications are not possible, ATC will ask other aircraft in the area to attempt contact by VHF. Similarly, the aircraft with the comms failure will attempt to contact other aircraft by VHF and request them to relay messages. As I said previously, there are plenty of aircraft in the air on most oceanic routes and it would be very unusual for an aircraft to lose all contact for more than an hour or so.
Airlines started flying across oceans a long time before SATCOM was invented. The problems associated with long-range communications are nothing new and there are well established procedures to cater for situations where an aircraft is unable to communicate with ATC. There are some differences between regions, but the standard ICAO procedures are described in the following link:: ICAO Communication Failure Procedures
In essence, ATC will assume the aircraft will continue to its destination as per its filed flight plan. The ATC provider will increase the separation standard it applies between the aircraft suffering the comms failure and other aircraft, and reserve airspace accordingly.
RE: “Well, one document which describes it is “LIGHT INFORMATION HANDBOOK” by the US Department of Defense, dated 6 JUL 2006. The procedure is “RADAR DISTRESS SIGNAL PROCEDURE FOR NATO OPERATIONAL AIR TRAFFIC”. However, there is another document “CANADA FLIGHT SUPPLEMENT / GPH 205”, effective 15 January 2009. Its “EMERGENCY COMMUNICATIONS PROCEDURES” chapter appears to be applicable to both civil and military planes. I relied on the latter in my modeling.”
As I said, it’s a manoeuvre used by MILITARY aircraft to alert MILITARY radar controllers in the event of a radio communications failure. The Canadian AIM does state that the radar alerting manoeuvre can be used by civil aircraft, but most other countries (Malaysia & Singapore included) do not mention the manoeuvre anywhere in their aeronautical manuals. I’d say it’s very unlikely the captain of MH370 would have known about the manoeuvre unless he had previous military experience (which he didn’t), let alone used it in the circumstances you described.
@DennisW. The quote from Ocean Infinity can be misleading as you say.
Add those I posted earlier:
– from an AFP report a Malaysian Deputy Transport Minister remark: “The company is demanding payment in the event the wreckage is found,” he told AFP….”
– from EFE news, “Mark Antelme, of Ocean Infinity, told EFE news on Thursday that the company will resume the search for free and will ask for a reward only if it manages to locate the wreckage…”
If a CPFF-type contract clearly there has been either some misleading, including of the Deputy Transport Minister, or misreporting; neither corrected since.
@Victor. The CPFF contract makes most sense all the same.
One could argue that since the search was suspended because success prospects were insufficient, a lower cost would not see it restarted. However, reductio ad absurdum if a new search cost nothing, even with low prospects it would go ahead, so a large cost reduction could come into it.
If that is in the offing, the risk to the customer as to whether the technology is proven and is both suitable and efficient might offset that. He/they would need to be convinced the risk is worth it.
Maybe that is what is afoot.
@Oleksandr
RE: “My understanding is that GP bus supplies position and attitude data to various user system, including the SDU (GP 1 bus – see p. 3263). However, this data is mixed data from the ADIRU, SAARU and GPS, in contrast to the ‘pure’ inertial data supplied via INS bus. Hence, it appears GP bus may still provide position and attitude to the SDU when the ADIRU fails.”
ARINC 429 data buses don’t ‘mix’ data from different sources; they send data from a single source to a maximum of 20 receivers. The B777 has six General Purpose buses that transmit different types of data to different systems. The Left GP 1 data bus sends time data from the L-AIMS UTC function (UTCF) to the SDU, nothing else. The UTCF does not output position data, so how can it possibly send GPS position data to the SDU?
Speculation for Malaysia’s possible conduct to engage Ocean Infinity’s service should consider how Malaysia contracted Go Phoenix and Phoenix International in 2014.
First, in July 2014, acting Minister of Transport Hishamuddin Hussein announced that two ships would be providing deep ocean sonar search, Go Phoenix embarking with Phoenix International, and the DOS/John Lethbridge capability. This announcement concerned only vessels contracted by Malaysia, at the same time ATSB was conducting its evaluation of proposals for the deep ocean search that led to Fugro’s contract.
Eventually, Malaysia engaged only Go Phoenix and Phoenix International using a byzantine arrangement where the contracting parties included Petronas for the vessel and DRB-Hicom Deftech for Phoenix International. These contracting arrangements were apparently made on behalf of the Government, Petronas lauded its contribution as part of a Corporate Social Responsibility obligation.
According to Wikipedia, Petronas is wholly owned by the government of Malaysia, and provides much income to Malaysia. Headquarters is the Petronas twin towers, the subject of a few fight simulator runs.
PS- Presumably Petronas also supplied the MH370 jet fuel
Andrew:
The Honeywell manual statements you cited” are correct, but (unintentionally) misleading statements. The same manual also states on pg 393:
“Signal Conditioning Unit
.
.
.
(2) The MCS system requires ARINC 429 data for antenna pointing, antenna
stabilization, and Doppler frequency correction. These requirements are defined in
Table A–10. If the aircraft does not have an IRS that supplies this ARINC data, the SCU can be used to supply the data.”
So, what this means is that a GPS hardware box can be connected to the SDU, but not directly. Instead, “If the aircraft does not have an IRS that supplies this ARINC data, the SCU can be used to supply the data.” The B777 does not need, therefore does not have an SCU. The B777 supplies all the data listed in A-10 via one high speed (100kb/s) 429 bus. Thus, there is, in the B777 installation, no hardware path for a GPS to “send data” to the SDU.
That said, there is a “software path” by which GPS data could be used (theoretically), without the aid of the IRS data, to produce a lat/lon/GS data stream (labels 310, 311, 312), but the SDU needs more than that to point the antenna. It needs everything in A-10. I hope that clarifies.
So the notion that the whole AES could have been functional without the AIMS supplying all the A-10 data does not work.
@ALSM
“without the aid of the IRS data, to produce a lat/lon/GS data stream (labels 310, 311, 312), but the SDU needs more than that to point the antenna.”
But, not for the LGA. Lat/Lon/GS would be sufficient (track implied along with GS).
@ALSM
Thanks, that’s understood. I hope it’s enough to convince Oleksandr, but I have my doubts.
@Donald
“I fail to see how this is not the widely accepted assumption!”
Everyone starts their journey through the MH370 mystery with their own set of beliefs and assumptions. These assumptions work on the thought process like axioms an a system of algebra. The conclusions you are able to reach are limited by the assumptions you make and the beliefs you hold.
In the case of MH370 we are not starting with a set of axioms and trying to infer from them, the answer to some specific problem but working the system in reverse. We have some knowledge about the outcome and what all the various investigators are trying to do, is imply from the evidence, what conditions must have been true to produce the observed outcomes.
To make a really convincing investigation, one must be prepared to test different set of assumptions (different sets of axioms) and see how they alter the possibilities. The different features and answer spaces of each set can be discussed and compared and a hypothesis built which relies on a balance of probabilities.
@Victor
Did you have a prior write-up or documentation on your BEDAX/South Pole path? Cannot seem to Google it up.
@Ulric
Do you have any ideas of different sets of assumptions (axioms) in mind to discuss and compare and hypothesise, based on what you have discovered so far following MH370 search?
@TBill: I first proposed it relative to a possible landing at Banda Aceh. Here are some of my thoughts from August 2014. Since that time, much more evidence has surfaced, and my thoughts have evolved. In any event, the path that includes a loiter over Sumatra and a path following BEDAX-SouthPole (equivalent to a true track of 180°) is the same. As the longitude of BEDAX is 93.8E, the crossing of the 7th arc is 34.3S, 93.8E.
@Andrew,
“ARINC 429 data buses don’t ‘mix’ data from different sources”.
I never wrote that ARINC 429 mixes data. The FMCF uses data from several sources: the ADIRU, SAARU, and GPS. The FMCF ‘mixes’ (or whatever term you prefer) navigation data, and makes output on GP buses of ARINC 429. My understanding of this part is exactly the same as ALSM described.
Re: “The Left GP 1 data bus sends time data from the L-AIMS UTC function (UTCF) to the SDU, nothing else.”
Then how do you explain citation from p.2985:
“General purpose bus 1 – universal time, time and distance to destination, and present position”?
It might be true that the SDU reads only time from GP 1, but I can’t understand why you insist that GP 1 provides only time data, and that FMCF does not send position data to GP 1.
Re: ” I’d say it’s very unlikely the captain of MH370 would have known about the manoeuvre unless he had previous military experience”
I am not a pilot, but I read about this maneuver… I would agree about such an assessment of F., a very young inexperienced pilot, but not Z., an ‘aviation geek’.
@Joseph Coleman
All of the ideas which have been tried out and evaluated are out there in various write ups by many authors. The better assumptions tend to come round in cycles because they have to be re-evaluated in the face of every new piece of evidence. I’m just watching to see which ones persistently recur.
@ALSM,
“If all INS data is lost, the algorithm could (theoretically) produce degraded 310 and 311 labels based on GPS data alone, but 324 and 325 can not be derived from GPS alone. Bottom line, the SDU can not and does not aim the HGA based on GPS alone.”
I think we are talking about different things. I have impression that you equate INS and the ADIRU. The SAARU also provides data to the AIMS, so if the ADIRU is lost, then then pitch (324) and roll (325) are still available from the SAARU. Or not? What do you mean under “INS is lost” in this context?
@ALSM,
@Andrew,
pdf p. 2184:
IRS data buses supply this data:
– Latitude and longitude (from the ADIRU)
– Magnetic track
– Ground speed
– True heading
– Vertical speed
– True track
– Inertial vertical speed and altitude
– Pitch and roll angle
– Pitch rate
– Normal acceleration
– Longitudinal acceleration
– Vertical acceleration.
p.
pdf p. 2185:
The general purpose (GP) data buses supply this data:
– Computed airspeed
– True airspeed
– Barometric altitude
– Baro-corrected altitude
– Barometric altitude rate
– Latitude and longitude (from the FMCF)
– Magnetic track
– Decision height
– Electronic flight instrument system (EFIS) control
panel (CP) control data
– Control display unit (CDU) control data (alternate
EFIS CP)
– Flap and gear position
– Indicated and corrected AOA
– Stick shaker AOA
– Minimum operating speed
– Air/ground status.
Note that both GP 1 and IRS buses may ‘theoretically’ provide longitude and latitude. However, IRS bus provides longitude and latitude sourced from the ADIRU, while GP 1 bus provides longitude and latitude from the FMCF.
It is not explicitly stated (or I did not find) whether IRS bus can receive pitch and roll data sourced from the SAARU or the ADIRU only.
@Victor
Thank you got it in my MH370/Papers-Iannello folder. It’s hard to distinguish between BEDAX or ISBIX as starting point but one or the other and then 180S is the base case most logical path (as far as a path radiating from the ping rings like a Perseid meteor radiates from constellation Perseus) to my thinking.
@Sk999,
“You then go on and quote text from the sections on the Ground Proximity Warning System and Flight Management Control System as if somehow it is relevant to the Satellite Communication System. ??? Just because a lot of signals are being passed around doesn’t mean that every system sees every one.”
I think there are two things:
1). What parameters are passed to a specific bus;
2). What parameters are read by some unit from that bus.
ARINC429 includes 3 relevant data buses: L & R IRS buses, and GP 1 bus. Andrew stated that GP 1 bus can provide only time. My understanding is that GP 1 can also provide position data, which is sourced from the FMCF in contrast to the INS buses. Does it matter what section of the manual this info is taken? FMCF uses data from the ADIRU, SAARU and GPS, does something with this data, and makes processed output to GP bus. The SAARU does not provide position, so that if the ADIRU fails, the FMCF may still ‘theoretically’ feed position data into GP buses using GPS data only – consistent with what ALSM says. But in contrast to ALSM, I think that pitch and roll data can reach the SDU from the SAARU (via ARINC 629 C, AIMS and INS bus of ARINC 429).
Of course, then it will be up to the SDU whether to use position data from GS 1 if position data from INS buses is not valid/available. But this is another issue. We did not reach it yet.
The GPWS text refers to “general purpose (GP) Data Buses” but does not specify which ones. Diagram on p. 23187 shows both 1 and 3 going to GPWC.
IFE, p. 2985 provides a little more info. UTC and present position are on GP bus 1. Altitude and airspeed are on GP bus 3. The IFE takes ground speed, track angle, and wind speed/direction from the IRS bus. What a mix!
CTU p. 3028, GP Bus 1 provides “ICAO”. (ICAO Address?)
SATCOM Control System, figure on p. 3245, shows “ICAO Address” and “IRS” going to SDU. The buses are not named, but the ICAO Address comes from L AIMS only; IRS comes from L AIMS and R AIMS.
SATCOM Interface diagram on p. 3263 show “GP 1 DATA” coming fro AIMS-L only. IRS DATA come from AIMS-L and AIMS-R both.
MCS-7200 manual, Table 5-5, “Contact Arrangements for Middle Insert, SDU ARINC 600 Connector” (page 5-6, pdf page 157) shows connections to these buses:
A4/B4: “AES ID INPUT”
A6/B6 “DATA FROM PRIMARY IRS”
C6/D7 “DATA FROM SECONARY IRS”
The Continental and Honeywell documents line up. There is only one line for the AES ID, and it is AIMS-L GP Bus 1. There are 2 lines for IRS data, and they are the AIMS-L and AIMS-R IRS buses.
Comments?
@Ulric
I suppose, there has to be at some point in the future Ideas or assumptions already thought of re-occurring, that may have been overlooked or dismissed perhaps, that may lead to that “final re-evaluation” that finally leads to the find. Who knows. For now MY individual thoughts I’ll just “expect the unexpected”.
It’s great to see some useful conversation on the Left AIMS Cabinet and what it does, ie feeds Flight ID to SDU, provides Mode S data to left transponder, etc
So what if the repressurised Crew oxygen bottle(s), which is inches from the Left AIMS Cabinet, ruptured like Qantas QF30 and caused a gradual decompression of the aircraft. Remember Malaysia is responsible for the servicing of the bottle.
Without a Left AIMS Cabinet it’s going to be extreme chaos for the Crew.
And if they programmed the standard RNP 10 route through the Malacca Straits to Banda Aceh via Nilam and Sanob, the aircraft can end 40-100 NM south of the Bayesian Hotspot.
@Oleksandr
RE: “I never wrote that ARINC 429 mixes data. The FMCF uses data from several sources: the ADIRU, SAARU, and GPS. The FMCF ‘mixes’ (or whatever term you prefer) navigation data, and makes output on GP buses of ARINC 429. “
Yes, the FMCF mixes position data from different sources to generate its own FMS position, but that’s not what you wrote the first time.
RE: ‘Then how do you explain citation from p.2985:
“General purpose bus 1 – universal time, time and distance to destination, and present position”?’
The GP 1 bus might well carry position data, but that does not mean the data is available to the SDU. ARINC 429 data words are made up of several fields, one of which is a source/destination identifier. If a data word is not addressed to a particular destination receiver (eg the SDU), then that receiver will not read the data. The position data on the GP 1 bus is NOT addressed to the SDU. According to the AMM, the only data provided to the SDU on the GP 1 bus is the time and date.
@sk999
RE: “The Continental and Honeywell documents line up. There is only one line for the AES ID, and it is AIMS-L GP Bus 1. “
According to the AMM, the AES ID (ie the ICAO identifier) is sent to the SDU via the L DCMF data bus.
@Don Thompson. Yes contractual support from government owned (and other?) businesses under the Corporate Responsibility Program is a different way of doing things.
http://www.themalaymailonline.com/malaysia/article/hishammuddin-petronas-to-pay-for-sonar-equipment-in-mh370-search#HsOIzXt5DzxDwP2a.97
http://www.thesundaily.my/news/1130701
I see the Program extends into social welfare.
http://www.theborneopost.com/2015/11/17/52-ngos-receive-rm25000-each-from-petronas/
Yes other businesses.
http://top10malaysia.com/main/csrs-shining-stars/
Andrew,
You may be right, but I still like my answer better.
According to the SATCOM interface diagram, DCMF buses from both AIMS-L and AIMS-R go to SDU. From the MCS-7200 manual, these would seem to correspond to the CMU buses (CMU = Communications Management Unit), of which there are 2, and both can provide the ICAO ID as well; the SDU monitors both along with the AES ID bus.
So there are three mysteries:
1. Why is the ICAO ID only provided on the AIMS-L DCMF bus, even though both are used otherwise?
2. What ICAO item is the CTU getting from GP Bus 1, if not the ICAO address?
3. Isn’t UTC available on the IRS bus as well?
@Paul Onions
Apparently you are OXY from JW site and we discussed this months ago, but Qantas QF30 was a metal O2 cylinder with a defect. According to the FI, MH370 had a composite (eg; KEVLAR) O2 bottle, that to my knowledge has no history of problems, and if it did unexpectedly fail, presumably would not fail in the same way that QF30 experienced. Also the general issue with mechanical failure scenarios for MH370 is that: (1) there is absolutely no evidence of such failure or fire (we only have proposed ideas of hypothetical failures), (2) the behavior of the aircraft is inconsistent and (3) lack of communications is not suggestive of a mechanical issue.
@Tbill
4) Disappeared right at hand-off (optimal moment to sow confusion and buy time), and dude in command had simulated flight deep into the SIO. Surely just coincidence. I could go on, of course.
And I’m still waiting for someone, anyone, to put forward a convincing and realistic scenario in which the PIC is deceased prior to EOF that does not consist of an unplanned for event/intervention or the exponentially more ridiculous ‘accident’ ghost flight theory/theories?
Unless we allow (which I suppose we have no choice in doing) for the occurrence of an unplanned for incapacitating or otherwise neutralizing event, then the default and irrefutable conclusion MUST be a living pilot in control until impact.
I’ve in the past given reasons why an intentional ghost flight (suicide before EOF) is patently absurd…but for reasons I’m incapable of grasping, people apparently think this to be a plausible possibility. It is not and should be discarded once and for all so that we can have greater clarity on the matter.
IMHO, the only fundamental determination (in regards to search area) still to made is whether or not the pilot pulled out of the intentional dive? This should be the primary focus of study and investigation, as it directly impacts the potential search area and chances of locating the aircraft.
@Donald: Determining the ground distance between the 7th arc and the impact site is important to defining the search area. Let’s put aside for a moment who, if anybody, might have been piloting the plane. How do we determine if the plane recovered and glided after the steep descent?
@VictorI
“How do we determine if the plane recovered and glided after the steep descent?”
Additionally, how do we determine where the descent began? While motive is interesting with respect to speculation, I find it difficult to infer a use for it as a means to refine the search area.
An exception might well be the data from Shah’s simulator.
The ongoing discussions relative to flight dynamics and electronic suite organization seem silly to me only because inputs from the manufacturers of the aircraft and all the equipment on it were/are available from well qualified people who were/are a part of the SSWG consulting team. They know exactly what the situation was. We are trying to stitch it together which will never be as good.
I am particularly disappointed with sk999’s attention to the above. I was hoping he was on the threshold of developing a method of deriving statistical inference from data associated with a non-stationary and non-ergodic process. I do have a portfolio to manage, and Black-Scholes is deeply flawed despite the Noble Prize.
@Andrew,
“The position data on the GP 1 bus is NOT addressed to the SDU. According to the AMM, the only data provided to the SDU on the GP 1 bus is the time and date. ”
Yes, it appears that sender and receiver are encoded into ARINC 429 data format, but I was unable to find any reference to yours “ONLY”. In addition, it appears @Sk999 is right:
Citation from p. 354:
Each AIMS cabinet transmits UTC and date data to other airplane systems on these ARINC 429 data buses:
– General purpose #1 bus
– General purpose #2 bus
– Inertial reference bus
– Central maintenance buses (L/C/R).
This indicates that UTC time must be available to the SDU on the IRS bus. Then a logical question is why the UTC time is taken by the SDU from GP 1, but not from the IRS?
One more question is what happens to the IRS bus when the ADIRU fails? Obviously, two fields, the latitude and longitude would be missing or marked as erroneous. But what about other parameters?
@TBill,
Your points were already addressed:
1) there is absolutely no evidence of such failure or fire (we only have proposed ideas of hypothetical failures),
There is absolutely no evidence of anything in the case of MH370. But something somehow went wrong.
(2) the behavior of the aircraft is inconsistent
On contrary. It is consistent with the emergency procedures handbook. There are, however, some ambiguities/disagreements on what crew would do, and what they would not do, where the handbook is not specific.
and (3) lack of communications is not suggestive of a mechanical issue.
There is only lack of communication via right VHF, which so far could not be explained. The rest is explainable.
@VictorI
On your remark;
‘How do we determine if the plane recovered and glided after the steep descent?’
I’m asking is it not better to include the assumption/possibility the plane recovered and glided after the steep descent in the light of maximum possible width of a new search area anyway?
To make sure this time no possible crash-area is left unsearched?
For I assume it will be impossible to determine if the plane recovered and glided after the steep descent..
If the final log-on was caused by the APU-start ~1 minute after second engine flame out, I reason the plane was still on high altitude (~30.000ft) when the steep descent was calculated between the 8 seconds BFO’s and the steep descent already set in directly after second engine flame out.
Then I would ask what would be the maximum possible altitude of a hypothetical recovery just after 0:19:37. Would the plane need ~4000ft to pull out for instance or ~6000ft?
Then I think you end up with a maximum possible altitude (in this case around ~20.000ft) at which a glide could have started.
Then you’ll also have a maximum possible gliding range (in this case around ~50 miles).
And with it a maximum possible crash-area that covers both possibilities:
a high speed steep descent/dive impact near the 7th arc or a glide and ditch-like impact further out the 7th arc.
@sk999
RE: “So there are three mysteries:
1. Why is the ICAO ID only provided on the AIMS-L DCMF bus, even though both are used otherwise?
I don’t know, but many of the ‘peripheral’ SDU inputs come from the left AIMS cabinet: Time/date, data load data, data load discrete, control & BITE signals. The aircraft position data and digital communications data come from both AIMS cabinets.
2. What ICAO item is the CTU getting from GP Bus 1, if not the ICAO address?
Again, I don’t know; I can only assume its the ICAO address, also known as the AES ID. Even so, that data won’t be available to the SDU on GP Bus 1 unless it is addressed accordingly. I assume they chose to send the ICAO address to the SDU via the DCMF bus because the SDU only monitors the CMU input ports and AES ID input port for that data.
3. Isn’t UTC available on the IRS bus as well?”
Yes. I don’t know why they chose to use GP Bus 1 rather than the IRS Bus to send time data to the SDU. Something to do with the input ports on the SDU perhaps??
@Ge Rijn, @Donald: At this point, I don’t have a good answer to how far from the 7th arc to search. I’m not fond of the scenario in which a pilot pulls out of a steep descent. (Why put the plane in a steep descent and then later decide to maximize the glide distance?) I also don’t want to miss the plane by not searching far enough from the arc.
A related question is in the event the plane is not found in the next search area, do we keep expanding the search area? Go further north, or further out from the arc? At what time, if ever, do we question the satellite data?
@Oleksandr
RE: ‘Yes, it appears that sender and receiver are encoded into ARINC 429 data format, but I was unable to find any reference to yours “ONLY”.’
The AMM specifies which data is sent to the SDU and on which bus. According to that information, the ONLY data that is sent to the SDU by the GP 1 bus is the time/date. If you choose to believe otherwise, that is your prerogative, but I think you are deluding yourself.
RE: “This indicates that UTC time must be available to the SDU on the IRS bus. Then a logical question is why the UTC time is taken by the SDU from GP 1, but not from the IRS?”
That data will NOT be available to the SDU on the IRS bus unless it addressed accordingly. See my reply to @sk999’s question above.
RE: “One more question is what happens to the IRS bus when the ADIRU fails? Obviously, two fields, the latitude and longitude would be missing or marked as erroneous. But what about other parameters?”
I assume that any other valid parameters would continue being transmitted. The time data on the IRS bus comes from the UTCF within AIMS, so it should still be valid. Nevertheless, it won’t be read by the SDU because unless it is addressed accordingly.
@Victor
>”Let’s put aside for a moment who, if anybody, might have been piloting the plane. How do we determine if the plane recovered and glided after the steep descent?”
Well, we begin by refusing to vacillate and wrangle (in our own minds) over ghost flight vs active pilot. We (everyone) need to rid ourselves once and for all of this silly ‘ghost flight’ scenario, no matter how inconvenient.
If you believe that you have squeezed every last bit of inference out of the EOF data when rigorously applying it to a living human hand, I’m afraid that we only have the sim data and psychology to fall back on.
My only hope and intention here is to attempt to convince people such as yourself that this EOF (pilot alive and in control) is worthy of your full attention.
> I’m not fond of the scenario in which a pilot pulls out of a steep descent. (Why put the plane in a steep descent and then later decide to maximize the glide distance?)
GeRijn above begins to grapple and engage with what IMO are the pertinent questions and scenarios.
Victor, I think it’s time we stop trying to ascribe rationale and logic to MH370. Why would someone fly 6 hours with a cabin full of dead people? I could go on with the why’s ad infinitum but I’ll spare your readers. I think you get the point.
IMO there is compelling background and psychological profiling that supports a pullout and glide. This includes, but is not restricted to, multiple videos that someone posted of airplanes performing water landings.
Of course, the debris should be conclusive…but incredibly it is not.
@Donald said: Sorry, but I remain unconvinced. But don’t feel bad. You’ve heard me say before that I have yet to hear a scenario that doesn’t have a significant hole, question, or inconsistency (except perhaps in the mind of the proposer).
@TBill
Re: “… Qantas QF30 was a metal O2 cylinder with a defect. According to the FI, MH370 had a composite (eg; KEVLAR) O2 bottle, that to my knowledge has no history of problems, and if it did unexpectedly fail, presumably would not fail in the same way that QF30 experienced.”
The QF30 investigation did not determine that the failed cylinder had a defect nor did it link the failure to the type or construction of the cylinder. From the Final Report,
“The ATSB undertook a close and detailed study of the cylinder type, including a review of all possible failure scenarios and an engineering evaluation of other cylinders from the same production batch and of the type in general. It was evident that the cylinder had failed by bursting through, or around the base – allowing the release of pressurised contents to project it vertically upwards. While it was hypothesised that the cylinder may have contained a defect or flaw, or been damaged in a way that promoted failure, there was no evidence found to support such a finding. Nor was there any evidence found to suggest the cylinders from the subject production batch, or the type in general, were in any way predisposed to premature failure.”
I don’t think that you can eliminate the possibility of a QF30esque oxygen cylinder failure simply on the basis of different construction materials.
There is at least one serious question mark hanging over the crew oxygen system on 9M-MRO; there is no evidence that the system was serviced on 14 January 2014 during an A4 check in the maintenance records listed in leaked RMP Report Folder 5.
@Oleksandr said: It [the aircraft behavior] is consistent with the emergency procedures handbook.
What procedure would recommend that a pilot with an emergency would not descend and land at a suitable, available, and familiar airport (Penang), but instead remain at altitude and continue past it? If there was too much fuel, the pilot would have landed heavy or dumped fuel while circling near the airport. If the pilot was not ready to land, he would have circled near Penang until he was ready. Since the night was clear, the airport would have been clearly visible. In fact, my guess is the pilot could have navigated from Kota Bharu to Penang using only familiar, visual references.
I’ve queried multiple B777 pilots and the consistent answer I get is the flight past Penang is contrary to what a pilot would do in an emergency. We are fortunate to have a former, experienced, and knowledgeable B777 pilot here (Andrew) that can provide valuable insight.
@Victor
Unconvinced of an alive pilot? Then put forward another scenario sans unplanned event (which I said cannot be definitively be ruled out) that holds up to any scrutiny?
The idea of intentional pilot suicide in between FMT and EOF is ludicrous, and that is all you have left. Unless aliens and accidents, which are on equal footing as far as I’m concerned.
What’s the difficulty here?
You either throw an unplanned for event into the thicket, or you have a plane under human control until EOF?
The burden is on those who disagree with the above statement to present a scenario that is plausible, and has the aircraft ending up in the SIO, where simulations were rehearsed?
@Donald: Please explain why a pilot would enter a 15,000 fpm (!) descent, pull out, and glide a long distance. I must have missed your explanation.
@Victor
Re: “I’ve queried multiple B777 pilots and the consistent answer I get is the flight past Penang is contrary to what a pilot would do in an emergency.”
I don’t disagree with that but it is predicated on having a conscious and coherent flight crew at that time; that may not necessarily have been the case.
@Donald
For the sake of clarity perhaps you could outline the pilot’s intent for the end-of-flight sequence under your hypothesis. Was it to fly as far south as possible? Execute a controlled ditching so as to minimise debris? Both? Something else?
@Mick Gilbert: My question pertained to Oleksandr’s assertion that the aircraft behavior is consistent with emergency procedures. I’d like to understand why he makes this assertion.
As for the possibility of a hypoxic pilot, as the duration of the aircraft’s unexplained behavior started near Kota Bharu when a descent was not commenced and lasted at least until after 18:28 when the turn to the SIO occurred, the pilot would have been alive yet hypoxic for about an hour. That is a very long time for a pilot to be hypoxic yet conscious.
@Victor
On Helios 552 we had a cabin crew member alive and conscious more than two hours after the unpressurised airplane had reached its cruising altitude of 34,000 feet. The autopsies on the crash victims that had not been burned in the post-crash fire showed that all were alive at the time of impact. A scenario whereby the flight crew were initially incapacitated but subsequently revived by a cabin crew member is not beyond the realm of possibilities.
@Mick
The points found on Shah’s simulator have no explanation other than a rehearsal of some sort for the intended diversion.
The most logical place to search given the inherent imprecision of the satellite and drift data is in the area near where the simulated flight path crosses the 7th arc. It so happens that this location can be reconciled with the drift data and the satellite data (interpreted with reasonable error models).
@Mick Gilbert: To the best of my knowledge, Helios 552 did not have a pilot conscious and hypoxic for an hour. For MH370, there were likely pilot inputs to turn the plane near IGARI at 17:21, turn near Penang at 17:52, intercept waypoint VAMPI and follow N571, execute an offset manoeuver at 18:22, power the left bus at 18:24, and initiate a turn or descent before 18:40. I don’t see how a hypoxic pilot could have executed so many procedures over such a long period, even if at some point he was incapacitated and later revived in an impaired state.
@Mick Gilbert, VictorI
The Greek AI&ASB wrote about Helios 552, “The forensic report concluded that the aircraft occupants had heart function during the impact. The report noted that this did not necessarily imply that they were alert. The report further estimated that they were in deep non-reversible coma due to their prolonged exposure (over 2.5 h) to the high hypoxic environment.“
@Dennis
> “The points found on Shah’s simulator have no explanation other than a rehearsal of some sort for the intended diversion. The most logical place to search given the inherent imprecision of the satellite and drift data is in the area near where the simulated flight path crosses the 7th arc.”
Now why would that be logical? Funny shit.
@Victor
>: Please explain why a pilot would enter a 15,000 fpm (!) descent, pull out, and glide a long distance. I must have missed your explanation.
i said previously “You either throw an unplanned for event into the thicket, or you have a plane under human control until EOF. The burden is on those who disagree with the above statement to present a scenario that is plausible, and has the aircraft ending up in the SIO, where simulations were rehearsed?”
I am not wedded to a glide. I’m agnostic, although I believe there is some less than compelling anecdotal and circumstantial evidence to support a glide, including someone’s passion for gliding, which injury prevented him from participating in for no small number of years. I’ll leave the psych part alone for the moment, as I’ve touched on it before (control, gliding down to preserve time, the surreal nature of what is happening etc…)
I’m arguing, by way of simple deduction, that there most certainly was a pilot alive and in control at impact, glide or no glide.
The initial dive was clearly initiated by a living person.
If you do not subscribe conclusively to an alive pilot at EOF, then perhaps you or someone else would be willing to put forth a scenario in which we have a ghost flight occurring where an unplanned for event did not occur? IMHO no such scenario of any real plausibility exists.
And if we are to make allowance for an unplanned event, I’d like to hear the nature of this event as well, and how the airplane just so happened to end up in the SIO despite some internal/external interdiction?
@Mick
You know some stuff about flying and airplanes and that’s great, but I respectfully don’t gauge your interest here to be objective in any genuine manner (sans agenda). Maybe I’m wrong, but at every turn you attempt to inject some level of disruption and convolution whenever the focus hones in on the intentionality and deliberateness of the event. Again, maybe this is my own confirmation bias. I certainly hope so.
i don”t pretend to know exactly what the pilots intention was vis a vis EOF. What I do believe is that he successfully executed his plan and arrived at his pre-determined destination without any upset.
Much like what is evident during the events that transpired in the previous hours, I would expect the person in control would have exerted himself in a such a way as to be consistent with execution and action at the time, place and manner of his choosing. He set the stage (after some, uh, rehearsal), zipped through acts 2,3,and 4, and landed himself properly during the 5th stage/encore.
If you yourself would care to dwell on just how this pilot would choose to spend his final moments, then I would be eager to engage.
The debris SHOULD tell us all we need to know about the EOF, but, again, incredibly it does not.
@Donald
“Now why would that be logical? Funny shit.”
A simple confluence of the observables.
@Dennis
“A simple confluence of the observables.”
8D chess you got going on. Impressive.
@Don Thompson
Correct, Don, with Helios 552 we’re talking about at least 150 minutes exposure to hypoxic hypoxia up to the time of death at impact; with MH370 we’re potentially talking about no more than 60 minutes exposure. I’m yet to find any reference that states revival would not be possible under such circumstances.
@VictorI
‘Why put the plane in a steep descent and then later decide to maximize the glide distance?’. I guess one can only speculate.
Maybe the pilot was near enough to his destinated end-location after the second engine flame out.
There would have been no need to maximize the glide distance but only for a glide to this specific location.
I rather think he would opt for minimizing a necessary glide distance and time to reach this objective. Then a steep descent before a glide could make sence.
@Ge Rijn: “Would the plane need ~4000ft to pull out for instance or ~6000ft?”
In the 8 seconds between the last two SATCOM transmissions the airplane would have descended about 1300 ft. Pulling out to a steady rate of descent of 2000 fpm would have required another 1500 ft. Those 2800 ft of altitude would not have been lost but would have been converted to excess speed. That excess speed could have been partially recovered in the the glide.
Why would someone do such a maneuver? To recover from a stall, for example.
@Victor. Gliding. Clues about the altitude at the 7th arc, hence potential glide distance, are the BFOs during the long leg south, which suggest not much of an altitude change during that, and also the distance, which requires altitude to be high.
In possible tension with these is lack of IFE ground connection in the final descent. One interpretation of that might mean the aircraft struck the water very shortly after the final log-on and hence the log-on altitude was low. If that was found likely that would suggest a piloted descent most probably starting before the 6th arc, concealed somehow within its BFO and beyond its current slow indicated descent. The purpose would be to increase powered range for a ditching, or because the pilot was reaching his planned destination with some fuel left. One would expect that supposing some allowance for en route weather uncertainty.
In the abstract a piloted final steep descent from low altitude would leave the impact very close to the 7th arc anyway, so a long powered descent would tend to decrease the width of the search area, not the reverse, even moreso than a continuing piloted dive from altitude assuming both are on a slant, or of course an unpiloted spiral.
But as to a long glide from a high altitude start, since a pilot gliding is unlikely to do so for long on a reversed course, such a glide should not entail widening of search width to the ‘rear’ of the arc. Indeed if, hypothetically, opinion among decision takers swung towards a long glide probability, the search width could well be seen as all ‘ahead’, its max/min boundaries set by likely starting altitude, the pilot having traded speed for height after the initial plunge as per your earlier simulation.
Yes there would have to be a reason for a plunge when this was to be followed by a pull up. One I have supposed is loss of pressurisation bleed air at fuel exhaustion. However, automatic closure of the outflow valves as cabin altitude rose to 11,000 ft would gainsay that. Maybe there is another explanation though I do not find Ge Rijn’s thought on that convincing.
Subject to that explanation I think that debris analysis is the most likely source of establishing there was a glide ending.
So far as I know the ATSB’s and Malaysians’ published debris accounts detail all that has been done. It is infeasible for us outsiders to get very far in isolation with that (which needs detailed debris examination, including the ultrasonic that ALSM has mentioned, plus design and manufacture data).
Thus in answer to your, “How do we determine if the plane recovered and glided after the steep descent?”, I think debris analysis offers the only avenue. Since that is out of our hands, other topics might be more rewarding. As to the investigators, it would be good if they have looked/will look into this but again only supposing a good reason for the initial dive came up.
However if (again hypothetically) it could be shown that there had been a powered descent from or before the 6th arc, though currently there is no evidence for that, including an active pilot possibility could lead to a reduced search width, not increased as I (at least) have supposed. Such serendipity would be useful.
BTW well trained paragliders are familiar with steep descents and pull outs before landing on a specific spot;
https://www.youtube.com/watch?v=pKCNHZRvtlo
As Victor said earlier, the problem with the piloted descent is the high rate of descent suggested by the final BFOs. How do you explain a rate of descent of somewhere between 15,000 ft/min and 25,000 ft/min? Even the lower end of that range is far greater than would be achieved in an emergency descent following a depressurisation, where the aircraft descends at MMO/VMO with full speedbrake and idle thrust.
Proponents of the piloted descent theory also need to explain how they would constrain the size of the search area to something achievable, given that the glide distance and direction are unknown. Rightly or wrongly, one of the reasons the ATSB stuck with the unpiloted theory is because it allowed them to limit the size of the search area and reduce the cost to something manageable and politically acceptable. That logic may seem flawed, but in the absence of conclusive evidence about the aircraft’s final flight path, the only other option was to do nothing.
@Victor @Andrew. I acknowledge that to fly past Penang with no sign of attempt to land is difficult to reconcile with an accident scenario. Can either of you imagine an accident/functional impairment scenario whereby a descent or circling might be counter-indicated and pilots have only very limited ability to manoeuvre?
@Donald: Here were my original questions: Determining the ground distance between the 7th arc and the impact site is important to defining the search area. Let’s put aside for a moment who, if anybody, might have been piloting the plane. How do we determine if the plane recovered and glided after the steep descent? And Please explain why a pilot would enter a 15,000 fpm (!) descent, pull out, and glide a long distance. I must have missed your explanation.
You provided lots of words, and lots of speculation. Unfortunately, you provided no useful information for answering my questions.
You did manage to say:
I am not wedded to a glide…
i don”t pretend to know exactly what the pilots intention was vis a vis EOF
So, despite your lengthy comments, you admit you don’t know the answers to my questions.
@Paul Smithson
“Can either of you imagine an accident/functional impairment scenario whereby a descent or circling might be counter-indicated and pilots have only very limited ability to manoeuvre?”
I will take a pass at it after hearing your explanation for the data recovered from Shah’s simulator.
@Victor
I feel the new search areas should be defined based on add’l and less constrained modeling, where we don’t give the model assumptions that preordain the answers.
If that is not possible, or does not help to clarify, I feel Inmarsat has made a tremendous contribution defining the 7th Arc. In the lack of other clarifying evidence, I favor prioritizing Arc7 (+-say 10nm). However, I see two Arc7’s, the inner (zero altitude Arc7) and the outer (FL350 Arc7). Some heartburn for me is that I feel the IG folks are favoring the outer Arc7 and beyond, and I like a slow pilot descent starting say 22:50 to the inner Arc7 and inside.
I also feel the BEDAX/ISBIX 180S @33-34S is what the modelling will probably say where the aircraft is most likely – because that’s where I think the BTO/BFO probably says it is – so I am semi-supportive of expanded search zone there, notwithstanding my preference to search Arc7 per se.
I am personally not visualizing that a live pilot would do a Gimli glider experiment. That takes me to a possible cloud-free zone where the aircraft visual profile would glisten for miles in the low morning Sun (per my test photos), with possible ship/air traffic making a visual. If I am alive and hiding the plane, I looking for a spot free of traffic and cloud covered, possibly back-tracking to that area since I already flew over it and picked it out. The spot is also over Broken Ridge into the rough deep areas. In the live pilot scenario, yes he might have conducted maneuvers at the end, that had the effect of accounting for the debris appearance that we are seeing.
@Paul Smithson
RE: “Can either of you imagine an accident/functional impairment scenario whereby a descent or circling might be counter-indicated and pilots have only very limited ability to manoeuvre?”
A total electrical failure might do it, but such a failure is highly improbable. It would require an extreme event such as a fire or explosion within the MEC to take out ALL the power distribution panels on both sides of the aircraft. It’s hard to imagine the aircraft remaining airborne for another seven hours after such an event and you’d also have to explain how power was restored to allow the SATCOM to keep transmitting.
@DennisW
You said (to Mick) “The points found on Shah’s simulator have no explanation other than a rehearsal of some sort for the intended diversion. The most logical place to search given the inherent imprecision of the satellite and drift data is in the area near where the simulated flight path crosses the 7th arc. It so happens that this location can be reconciled with the drift data and the satellite data (interpreted with reasonable error models).”
I simply don’t believe Shah would have been stupid enough to leave anything of real value to us on his hard drive. He was smart enough to know that the hard drive would be examined. In fact, this guy was infuriatingly smart. He deliberately left tantalizing but deliberately vague clues as to his intentions with one purpose and one purpose only – to taunt his “enemies”, ie the Malaysian authorities. He could have destroyed the hard drive, but that would have been a bit too obvious, and an obvious admission of guilt. What he was saying with this SIM data was “yes you’re right, I was planning to end up in the SIO after clearing the tip of Sumatra, but good luck in finding where I actually went.”
@Victor,
You asked: “What procedure would recommend that a pilot with an emergency would not descend and land at a suitable, available, and familiar airport (Penang), but instead remain at altitude and continue past it?”
The first thing a pilot would do is to refer to the emergency handbook, correct?
Prior Penang section:
Check, for example, Boeing-777 Quick Reference Handbook, in particular “Smoke, Fire or Fumes” section. Item #1: “Diversion may be needed.”. Item #14: “Initiate a diversion to the nearest suitable airport while continuing the checklist”. Descent is not mentioned in between. It is first suggested in Item #15 if “fire or
fumes situation becomes uncontrollable”. Furthermore, in order to reach a suitable landing place as soon as possible, it would be logical to maintain flight level. So why would the crew go against QRH and logic? Flying to the nearest landing location (Sultan Ismail Airport) and then to the nearest suitable lading location (Penang) are consistent with QRH in my opinion. In addition, what other scenario can explain manual aviating?
Near Penang:
Do remember that the radar altitude, gaps in the radar data, and mobile phone connection, all are indicative of comparatively low altitude? In my opinion, this could indicate preparation for landing.
Past Penang phase to FMT:
My hypothesis is that the first turn near Penang was an attempt to enter holding pattern. But something went wrong: hypoxia, inability to jettison fuel, panic onboard, etc. This caused delay of 20 minutes to sort out higher-priority issues before PIC attempted to perform the radar alerting maneuver, ending with one extra leg. In other words I consider the FMT as an erroneous exit from a triangular holding pattern.
Past FMT phase:
No active human control.
Other comments:
Re: “If there was too much fuel, the pilot would have landed heavy or dumped fuel while circling near the airport.”
It would be suicide to land with full tanks if the nose landing gear was damaged, and no ground emergency services were on standby. If the main L bus was depowered as a preventive measure against fire spread, the crew would not be able to jettison fuel.
Re: “If the pilot was not ready to land, he would have circled near Penang until he was ready.”
I think this could be their intent. But I assume something went wrong at Penang, possibly due to hypoxia affecting PIC.
Re: “I’ve queried multiple B777 pilots and the consistent answer I get is the flight past Penang is contrary to what a pilot would do in an emergency.”
Agree. But this is true only if you assume that both the pilots and other crew members were in a healthy state of mind by 18:00, no panic onboard, etc. Do remember that we are discussing this for 3 years, while they possibly had only 20 minutes to assess damages and select appropriate actions, while keep on aviating?
Re: “I don’t see how a hypoxic pilot could have executed so many procedures over such a long period”.
This is because you consider that everyone was impacted by hypoxia simultaneously and in equal degree. Just imagine one pilot became a victim of hypoxia sooner (in 20-30 minutes) because he relied on the oxygen tank in EE-bay. The other one, likely Z., survived longer (say till 19:00) because he used portable oxygen bottle while assessing damages outside of the cockpit.
@Andrew
You said “Proponents of the piloted descent theory also need to explain how they would constrain the size of the search area to something achievable, given that the glide distance and direction are unknown. Rightly or wrongly, one of the reasons the ATSB stuck with the unpiloted theory is because it allowed them to limit the size of the search area and reduce the cost to something manageable and politically acceptable. That logic may seem flawed, but in the absence of conclusive evidence about the aircraft’s final flight path, the only other option was to do nothing.”
Andrew, we’re on the same page! Exactly what I’ve been saying all along: the ATSB have clung doggedly to the “no pilot control in descent” scenario, and defended it at all costs against the likes of Byron Bailey and others simply for political expediency and to keep the search are to a practical size. But what if the pilot HAD actively glide the plane after the fuel ran out? What evidence is there to suggest an extended glide could have occurred? I know I’m in a minority of one, but a terminus carefully synchronized with sunrise might be a positive clue. Then there is the debris. The debris does not suggest an uncontrolled (probably nose-first) high speed impact, it suggests more, a controlled, high vertical descent rate impact, one intended to promote a rapid sinking in one piece, with minimal floating debris.
To those of you who object on the grounds of no debris washed up in WA, I’ve already that one. My reply is that the debris from S38/S39 floated due north then due west toward the East African coast, just like the ATSB and CSIRO said it would have after the flaperon was washed ashore on Reunion, but before their failure to find the aircraft within unpiloted, careering distance of the 7th arc, whereupon they changed their story to suit.
@David, others: A helpful turn to the conversation — the suggestion that any piloted terminal glide would reasonably maintain the heading and remain near the 7th arc. Eg, if a pilot was aiming for low-energy crash on some pre-specified site [which I doubt btw] they would have entered a heading to reach it, and maneuvers after flame out would hold that heading. No reason for ‘evasion’ if pilot was unaware of Inmarsat evidence. Nor would evasion help if he thought he might be tracked by radar or chase plane..
And any unpiloted EOF scenarios result in spiral high energy crashes near the 7th arc.
@TBill: Problem with 33-34S is high likelihood of debris in WA [unless, as at 35S, a strong westerly current is proposed].
Still nothing very promising if Ocean Infinity were to risk their own costs..
@Rob
What your view has consistently misinterpreted are:
1> Why has no debris been found in WA?
2> Why did Shah divert the aircraft in the first place?
The answer to the first question is obvious. The aircraft terminated North of 35S.
The answer to the second question is much less obvious. It is clear (to me) that the loss of the aircraft was not the preferred outcome of the diversion. It was a possible outcome based on how events might unfold relative to the real purpose of the diversion. The communication Shah had just prior to take off is very telling in this regard as is the flight path prior to the turn South.
@Ikr
I am under the impression the Bayesian techniques can weigh fuzzy data like aircraft visual searches and drift analysis. Clearly my preference is to assign greater weight to the Inmarsat hard data and use draft studies as approximate, but mostly I’d like to an see an impartial scientific approach, which NTSB might do (or contract out) if it were a USA crash.
@Andrew
On your remark:
‘Proponents of the piloted descent theory also need to explain how they would constrain the size of the search area to something achievable, given that the glide distance and direction are unknown.’
I argue that if excepted the steep descent after second engine flame out and between 0:19:29 and 0:19:37 took place and assumed a pull-out and glide took place after 0:19:37 this pull out had a theoretical maximum start altitude and maximum ending altitude after 0:19:37 where a glide could have been started.
This maximum pull-out ending altidude and possible start of a glide then would ~define a maximum glide-radius.
I argue a possible start of a pull-out right after 0:19:37 with those high descent rates would teke a minimum amount of altitude; 4000ft, 6000ft, 8000ft?
I don’t know. You probably would know?
I think a maximum possible glide radius would be within ~50 miles around any possible point on the 7th arc.
@ikr
Bayesian techniques are very useful when hard data exists. The classic example is the age at which women should begin mammogram testing. This age is the result of the probability of a disease versus the false positives of the test itself.
In the case of weighting the data associated with the Inmarsat data and the drift analytics, the weighting is entirely subjective. In other words it is basically useless. It does not constitute a “scientific” approach.
@Oleksandr: In an emergency, the reason to divert to an airport is to land. A normal descent from 35,000 ft would require about 115 NM, which means the descent into Penang would have begun after passing Kota Bharu. If the fire was uncontrollable, even an earlier descent is recommended, as the QRH states. The fact that no descent was initiated means the emergency procedures were not being followed.
If you think that speeds in excess of 500 kn near Penang are consistent with low altitudes and preparing to land, you are mistaken. And Mike Exner has shown that a cell phone connect is possible at 35,000 ft.
You now are recognizing that flying away from Penang is not consistent with emergency procedures. You explain away the many inconsistent actions with emergency procedures over some length of time as indicating a kind of tag-team hypoxia.
I know your mind is made up that there was an onboard failure. For me, with all we know, that is very unlikely.
@Andrew
Further arguments on constraining the size of the search area if it was a piloted descent including a glide would be;
-the location has to be within the possible lat/longs according the latest drift analizes (between 35S and ~30S) and the Inmarsat data.
-if piloted we also would have to assume the pilot had a specific crash location planned with a certain reason. Regarding the few found pieces of debris this was likely to be a location where he could hide the plane as good as possible with the least possible amount of floatig debris.
-there are only a few locations/areas between 35S and 30S that serve this criteria; some deep trenches/holes just under Broken Ridge. Which define a crash latitude south of ~32S (under Broken Ridge).
-those locations/areas have to be within a maximum glide-radius of ~50/60 miles after the steep descent. Which define crash longitudes between ~95E and ~97E.
The best locations/areas meeting the above criteria are the +5000m trenches/holes starting just east of the 7th arc at ~32.27’S/96.55’E till ~33S/~97E; Ob’Trench.
Taking also the west part beside the 7th arc into account the whole search area would cover a roughly estimated ~40.000km2.
With imo the best prospects east of the 7th arc.
Correcting; a roughly estimated ~10.000km2..
@Mick
Like you I also gravitate to the O2 supply angle because as a retired chem engr I have managed more than my fair share of gas cylinders. Admittedly the special aircraft light-weight gas cylinders is not my direct experience. In checking into MH370 previously I think I saw the Qantas QF30-type metal cylinders – not used on MH37O – had some history of defects/replacements. I saw no apparent issues with the composite style used on MH370.
I noticed that Helios had an 800-psi O2 tank refill target, so I was wondering why they refilled MH370 at 1200-psi, but apparently that was standard MAS practice. I find it a little suspicious the O2 tank was refilled before flight, but can see no “smoking gun” within the limited data in the FI/police report. I would like to see a record of O2 pressures after each prior 9M-MRO flight, but I think that’s in the long list of proprietary data MY is holding secret.
@TBill
Yes, Z probably anticipated that as well, and rehearsed what he might do in case of an O2 failure, and he was forced to route West to Penang, suffer hypoxia, recover, and then route South.
Absolutely unbelievable that either of you can possibly cling to your scenario.
@DennisW
Just to be clear to the readers, I currently see no likely scenario on O2 failure or any other failure. Overall on MH370 I am quite aligned with Victor to be honest. I only got into O2 because Paul Onions brought it up as a proposed failure.
@Victor,
Re: “A normal descent from 35,000 ft would require about 115 NM, which means the descent into Penang would have begun after passing Kota Bharu.”
Yes, just after passing Kota Bharu.
Re: “If you think that speeds in excess of 500 kn near Penang are consistent with low altitudes and preparing to land, you are mistaken.”
Firstly, you assumed/derived that the speed was in excess of 500 kn near Penang. No radar data was released to confirm this. You can derive average speed, filtered speeds etc., but it does not mean that the local speed at Penang was the same as the average speed. Take a look at DSTG Fig 4.2. DSTG says they were provided with 10 seconds samples, but FI states there was only 50 seconds of radar track near Penang, meaning that the DSTG received 5 or 6 samples of ‘real’ data, while the rest was interpolation/extrapolation.
Secondly, how do you know that the speed was constant near Penang? Especially if descent took place?
Thirdly, 500 knots are reachable at approximately FL250 (considering KIAS 330 or 355, wind, and descent). Far lower than FL350. DSTG’s estimates of the lower bound at Penang are of order 450-470 knots, btw.
Fourthly, the DSTG admitted some slowdown after Penang.
Bottom line: your argument is not sufficient to justify 500 knots at constant FL350.
Re: “You now are recognizing that flying away from Penang is not consistent with emergency procedures.”
Currently my view is that it might be consistent with the radar alerting maneuver or emergency descent maneuver. The former provides an opportunity to explain the FMT as a result of a simple counting mistake, so that the final heading/track was approximately 170 degrees immediately after the FMT.
Re: “You explain away the many inconsistent actions with emergency procedures over some length of time as indicating a kind of tag-team hypoxia.”
Do you think that the crew became incapacitated in a fraction of a second? Or the “process of incapacitation” could take some time, during which the crew could make mistakes?
Re: “I know your mind is made up that there was an onboard failure”.
Not really. I only consider it as one of the most plausible scenarios.
@Oleksandr
RE: “Item #1: “Diversion may be needed.”. Item #14: “Initiate a diversion to the nearest suitable airport while continuing the checklist”. Descent is not mentioned in between. It is first suggested in Item #15 if “fire or
fumes situation becomes uncontrollable”. Furthermore, in order to reach a suitable landing place as soon as possible, it would be logical to maintain flight level. So why would the crew go against QRH and logic? “
The objective of the Smoke, Fire or Fumes checklist is to land the aircraft ASAP. Step 8 of the checklist that was current at the time of MH370 refers the crew to the Smoke or Fumes Removal (SFR) checklist ANY TIME the smoke or fumes becomes the greatest threat. The second step of the SFR checklist says “Do not delay landing in an attempt to complete the following steps.”
Maintaining a high altitude is not necessarily the fastest way to reach a suitable landing place. The highest TAS is achieved at about FL300, where MMO=VMO. In any case, the normal descent point for Penang would have been reached about the time the aircraft crossed the coast near Kota Bharu.
“This caused delay of 20 minutes to sort out higher-priority issues before PIC attempted to perform the radar alerting maneuver,…”
Why would the crew even consider a radar alerting manoeuvre at the top end of the Malacca straight? Who were they supposed to be alerting?
“It would be suicide to land with full tanks if the nose landing gear was damaged, and no ground emergency services were on standby. If the main L bus was depowered as a preventive measure against fire spread, the crew would not be able to jettison fuel.”
The aircraft might have landed with a considerable amount of fuel remaining, but the tanks were nowhere near ‘full’. Landing with a damaged nose landing gear is not as bad as landing with a damaged main landing gear. What do you think imposes the greater risk, landing with a damaged nose landing gear, or continuing flight with smoke filling the cabin? In any case, how would the crew know the nose landing gear was damaged until they tried to extend the gear for landing?
@Oleksandr: The intermittent data in the FI referred to primary civil radar data, not the military data. The plane rounded to the south of Penang at around 17:52. The DSTG speed plot shows the best estimate speed to be around 524 kn at this time. The military radar data shown in the RMP report labels the radar captures south of Penang with speeds between 520 and 528 kn. These speeds are not consistent with “comparatively low altitude” and “preparation for landing” at Penang. In fact, there is no evidence that there was any attempt to land at Penang.
The slow down after Penang that the DSTG believed was possible would have occurred after 18:02, i.e., after passing Penang. By the way, the slow down was based on the BTO data at 18:25. However, the lateral offset manoeuver, or other paths to the right of the N571, removes the need for this slow down, as I showed in my first blog post.
I never claimed hypoxia occurs in a “fraction of a second”, and you know it. However, I do believe that behavior attributed to hypoxia is very unlikely to occur over a period of an hour. The probability of tag-team hypoxia is ridiculously low.
I also agree with the points that Andrew made, which I won’t repeat here. Even if you choose to not believe me, you are unwise to not believe Andrew relative to how a B777 pilot would react in an emergency.
@VictorI
Yes, the failure mode and variations on that theme are (or should be) a dead issue. To me the main work should concentrate on combining the information we have in an intelligent manner. Refinement of the ISAT data is a waste of time IMO.
@all
More…
The likelihood of a resumed search is extremely low IMO. My “look see” into Ocean Infinity shows a marginally capitalized company who can ill afford to conduct a search on its own nickel as widely reported. The whole offer is a thinly disguised marketing ploy. There is little doubt about that. Sorry to be the messenger.
@DennisW,
Concerning Ocean Infinity, that’s a unnecessarily pessimistic view. My “look see”, across openly published information related to OI, and its partners, indicates that Swire Seabed maintains a signficant interest. Swire Seabed’s ultimate owner is John Swire & Sons Ltd.
@Don Thompson, @DennisW: Until we know more about the offer, it is possible that the offer was not nearly as generous as was reported, and their search would require OI to put much less at risk than was reported. This confusion may arise because OI chose to use words like “economic risk” and “fee only if it is successful”, and reporters don’t understand terminology used in contracts. I also agree that the JV partners that own OI have substantial resources that go well beyond how OI is capitalized.
If OI made the offer as a marketing ploy without the expectation of it being accepted, they are doing it in a strange way. The offer only became public knowledge because some of the NOK learned of the offer through unofficial channels and decided to publicize their knowledge of the offer when they saw no movement and no announcement after several months.
That said, the OI offer seems to be the best option at this time for re-starting the search. I hope there is a way for the parties to come to an agreement.
@All
The DSTG Bayesian Hotspot wasn’t plucked out of thin air. It was derived as a statistical best fit of the BTO values. That the result aligns closely with maximum range cruise in a post FMT straight line MUST be of statistical significance, imho. If the aircraft had for example, followed heading 175deg after FMT, then the MRC line would be in a totally different place, and the BTO arcs would be in totally different places.
This means that the Bayesian best fit trajectory, with initial (post FMT) heading of 186deg, crossing the 7th arc at S37.75 approx, represents the maximum distance obtainable on the available fuel, and therefore represents the “independent variable” ie the trajectory that depends only on the available fuel and aircraft performance, and can be thought of as being the trajectory that defined the positions of the arcs, in particular, the 7th arc. All trajectories crossing the 7th arc at points east of the independent trajectory, should be considered as “dependent variables” – dependent on the location of the 7th arc as determined by the aforesaid independent variable trajectory.
Each individual “dependent variable” trajectory has to follow a specific path with varying heading and specific non-optimal cruising speed if it is going to cross the 7th arc at fuel exhaustion. The further east one goes the more one has to invoke unlikely scenarios such as pre FMT loiters in order to make these dependent trajectories fit the ISAT data and aircraft performance data.
In the absence of any firm evidence that the aircraft followed a non optimal trajectory following FMT, it tells me that the DSTG hotspot remains the prime terminus
@Rob: I suggest you review the assumptions that went into the DSTG hot spot prediction. For instance, there was an a priori distribution on the number and types of manoeuvers, an assumption that the plane was flying level at 18:40, and an assumption that any Mach number between 0.73 and 0.84 had sufficient endurance. The reality is that we don’t know how the plane was flown between 18:28 and 19:40. There might have been changes in altitude, a loiter, an excursion, or any number of paths that include more than one turn that you claim are “unlikely”. The only way your scenario is correct is if the plane glided after the steep descent AND the drift modeling is wrong. At this point, I’d say the combined probability is very small.
@Victor/Don
So lets play the estimating game as though we were the owners of Ocean Infinity. What makes sense relative to a formula to calculate a “reward” based fee? Not a CPFF arrangement.
The way VC’s look at it is similar to a dice roll. Assume a 10-sided die. If you bet a dollar on any particular number you wound expect a 10x payback in order to stay “flat” relative to an ensemble of such bets. Like flipping an unbiased coin, a 2x payback implies that you stay flat relative to your basis. So the minimum payback is the reciprocal of the probability of a successful outcome.
What is the probability of a successful outcome of a renewed search, and how much will it cost? Tough questions, but we can make some arbitrary choices and see where that leads. Suppose OI estimates a 70% success associated with a 25,000 km^2 search. The minimum sensible payback is the reciprocal of 0.7 or 1.43. Call it 1.5 in round terms. So what is the cost for searching 25,000 km^2? The cost of the previous search is widely reported to be $150M (USD) for 120,000 km^2. This cost includes search cost plus startup cost (considered later). At the same per km^2 cost the 25,000 km^2 search would cost about $30M+. Making a totally wild guess that the OI technology is twice as efficient as the towed scanners would imply a cost of $15M+. Add in a guess of $5M to get everything organized in Perth and you have roughly $20M out of pocket. At the minimum sensible payback you would need a “reward” of $30M to undertake the project.
OK, so all the above is “arm waving”, but it sort of hangs together. My guess is the “reward” OI proposed is in the range of $30M to $50M (assuming the “reward” concept is how the offer was structured). I would view that offer as “fair” if I were the Malays.
Of course, a contract with OI on the above basis raises the spectre of a potential “whistle blower”. If someone knows the terminus of the aircraft it would be tempting to approach OI with an offer to point them at it for a few million. The fact that the Malays have not gone ahead with OI may well be due to this wrinkle. The whistle blower could even be a third party US government type who is privy to highly classified information. It may also be that the Malays simply don’t care enough about where the plane is to spend $30M to $50M finding it. A not unlikely state of affairs.
Sorry, for blowing a lot of smoke around a serious site.
@DennisW: For what it’s worth, the number you have arrived at is similar to the number that I have heard from parties not associated with the negotiation.
@DennisW
I would think OI can use and build on all the information gathered and the things done by the ATSB’s and others which reduces their costs substantialy.
The 150 million dollar search included everything I assume; the (very costly) airial search, all the research, all the search efforts prior to the actual ‘big search’ in the previously destinated priority area.
And they can use all information before and after the search was suspended by all other independent (public) searchers and researchers.
And maybe even more important; OI is a completely independent private company.
This all gives them big advantages the ATSB never had imo.
And with doing this offer I think they have a clear view on where to search already. They probably have information we don’t have yet and they are quite sure of it.
Making such fuzz only for marketing reasons I don’t believe. It would be very bad advertising among serious competitors and potential cliënts.
And with their method a 25.000km2 search could be accomplished in maybe one third of the time it would take by the previous method used.
With probably also one third of the costs.
@Ge Rijn: I agree with the gist of your comment. I have learned more that I will be sharing soon.
[Comments here are closed. Please continue the discussion under the new post.]