Re: *The Seattle Times* article.

The legal eagles at Boeing will be under a fair bit of pressure, and the lid hasn’t yet been put on the pot.

The rather duplicitous actions described in the article permeating throughout the design, engineering, testing, certification and managerial levels of the organization; seemingly at the behest of the executive, can only be described as “chilling”.

And the excuse; not to let Airbus gain the lead in the short / medium haul market.

]]>The inside story of MCAS: How Boeing’s 737 MAX system gained power and lost safeguards ]]>

Mahathir raised the possibility of a remote take over shortly after MH370 disappeared, when he also accused the CIA of withholding information:

CIA withholding information on flight MH370, says former Malaysian PM Mahathir Mohamad

Many years ago, the former Australian prime minister, Paul Keating, labeled Mahathir Mohamad as a ‘recalcitrant’ and he is well known for his antipathy towards Western countries. For example, it was reported in *The Australian* that Mahathir once *speculated that the 9/11 events were staged by the US “as an excuse to mount attacks on the Muslim world”*:

CIA ‘role’ alleged in plane mystery

This comes on the heels of his claim that there is no proof that Russia downed MH17.

]]>I echo Richard’s sentiments. Thank you for your offer, but I believe our combined ROI search efforts over the past several years are adequate.

@TBill,

@DennisW,

Regarding “But I am having trouble seeing how active flight paths might not be (a) better fit”, I will say that, from a statistical point of view, no active route can be SUPERIOR to the LNAV 180 route through BEDAX.

It’s easy to create maneuvers during “active” routes which result in smaller BTO and BFO residuals, but that does not mean they are more likely. In fact, the smaller the residuals are than their expected values, the LESS likely is the route.

The LNAV 180 BEDAX route appears to be the only passive route which is fully consistent with statistical expectations. One can create active routes which are EQUALLY likely, but not significantly MORE likely.

@David,

You asked: “Do we know the accuracy boundaries for wind, temperature and density altitude data on the different routes, particularly in the remote regions?”

The simple answer is, not as well as we would like to know them.

Richard has compared a limited set of temperature and wind measurements made by 9M-MRO during MH371 with GDAS data. This will be reported in our next paper. Roughly, the temperature differences were about 1-2 C and the wind differences were about a knot in speed and several degrees in direction. I note that this latter result is superior to the expected GDAS global wind errors. It indicates that with our 4-D GDAS route models, we can predict the ground speed with systematic errors in the range of 1 to several knots, and this is most useful in discriminating routes. It is an integral part of my new route fitting method, because synthesizing small ground speed errors for each leg (mostly caused by GDAS errors), is the only way to segregate the systematic route errors from the random BTO reading errors using the MH370 data set.

]]>There are four varieties of statistical analyses which I employ in my new method of MH370 route fitting.

To review, a list of the statistics I use is:

1. Mean BTOR (mu_s = 0, sigma_s = 12.97 microsec, 5 samples)

2. STDEV BTOR (mu_s = 27.30, sigma_s = 9.90 microsec, 5 samples)

3. STDEV BFOR (mu_s = 3.90, sigma_s = 1.73 Hz, 5 samples)

4. Pearson’s correlation coefficient r for Leg Start BTOR to Leg End BTOR (mu_s = -0.237, sigma_s = 0.447, 4 sample pairs)

5. r for Leg Start BFOR to Leg End BFOR (mu_s = -0.237, sigma_s = 0.447, 4 sample pairs)

6. r for BTOR to BFOR (mu_s = 0, sigma_s = 0.50, 5 sample pairs)

7. r for BTOR to Time (mu_s = 0, sigma_s = 0.50, 5 sample pairs)

8. r for BFOR to Time (mu_s = 0, sigma_s = 0.50, 5 sample pairs)

9. r for BTOR to Along-Track Position Error (mu_s = 0, sigma_s = 0.50, 5 sample pairs)

10. PDA (mu_s = +1.5% or -0.8%, whichever is closer, sigma_s = 0.67%, 1 sample)

11. r for BTOR to Cross-Track Position Error (mu_s = 0, sigma_s = 0.50, 5 sample pairs)

12. r for Along-Track Position Error to Cross-Track Position Error (mu_s = 0, sigma_s = 0.50, 5 sample pairs)

In this list, I use the subscript “s” to denote “sample” statistical values, as opposed to “population” values. The sample standard deviations are smaller than the population standard deviations. Generally speaking, there are 5 samples (and in two cases of autocorrelation there are 4 pairs of samples). I denote the expected values by “mu” and the standard deviations by “sigma”. BTOR is BTO residual. BFOR is BFO residual.

1. The first category of statistics used in my new MH370 route fitter is the simplest. It applies to normal random variables, such as the Mean BTOR (my statistic #1 in the list above) and STDEV BTOR (#2). In this case we know that for the True Route the mu_BTOR = 0 and the population sigma is 29 microseconds. The expected value of the calculated sample mean BTOR (with N = 5) is zero, and 100,000 random trial sets of BTORs gave a mean of -0.07 microseconds. The sample standard deviation of the mean BTOR with 5 samples is expected to be 29/SQRT(5) = 12.97 microseconds. The 100,000 trial sets gave an average (sample mean) standard deviation value of 12.98 microseconds. So, the trials match the expected statistical values very closely for the BTORs.

The sample BTOR standard deviation is less than the population standard deviation of 29 microseconds, because of the limited number of samples. 100.000 trial sets had an average value of 27.30 Hz. The observed standard deviation of the sample BTOR standard deviation was expected to be 29*SQRT(1-9*PI()/32) = 9.90 microseconds, and the 100,000 trials gave an average of 9.90 microseconds.

So, the mean and standard deviation BTOR statistics appear to behave as expected.

In this category we simply find the Z transformation statistic as:

Z = ( Value – average sample mean) / sample standard deviation

and we find the percentile P (in EXCEL) from:

P = 2*NORM.S.DIST(-ABS(Z),1)

where the factor of 2 is needed because of the cumulative single-tailed normal distribution function used in EXCEL. We must use the absolute value of Z because we don’t know its sign. Here P is the percentile of random trials which are worse than the current fit, assuming the route is True.

I also treat the Performance Degradation Allowance (PDA, #10 in the list above) as a normal random variable and use the same analysis method. Recall that the PDA is determined by adjusting it so that Main Engines Fuel Exhaustion is predicted to occur at 00:17:30 UTC. The PDA is not a random variable in the strictest sense, but it has the same characteristics of interest in this problem. The expected value of the PDA is nominally the MH370 Flight Plan value of 1.50% (average of both engines in cruise). However, because we cannot rule out the possibility that the air packs were turned off at Diversion, the effective value could be much less averaged over the remainder of the flight. The impact of the air packs being off is about 2.3% in fuel savings, or an equivalent PDA of -0.8%. So, to allow for this possibility, I allow the PDA expected value to be either +1.5% or -0.8%, whichever is closer to the best-fit value. The uncertainty in the PDA is caused by the errors in the fuel consumption model. Based on comparisons with previous flights and with Boeing fuel flow tables, I have previously estimated that uncertainty to be 2.0% at the 3-sigma level. Thus one sigma is 0.67% in PDA. Treating the PDA in this fashion allows me to estimate a probability that the route being fitted matches the expected PDA. It also allows me to incorporate PDA as one of numerous statistics being evaluated to produce a single overall figure of merit for the fitted route. The PDA percentile is calculated as described above for the BTOR statistics using the Z transformation and the normal distribution.

2. A second category of statistical analysis is the STDEV BFOR (#3 in my list above).

I use an empirical method to match the DSTG’s empirical density function of the BFO reading errors. This involves generating normal random values having a zero mean and a population standard deviation that itself is a uniform random variable from 1 to 7 Hz. The average value of 100,000 trial sets of 5 BFORs was 0.004 Hz and the average population standard deviation was 4.35 Hz. This is in agreement with the DSTG estimate for BFO reading errors with outliers excluded. To find the percentile value, I find the Z transformation as follows:

Z = (value – average sample BFOR standard deviation ) / standard deviation of sample BFOR standard deviation

The average value of the sample BFOR standard deviation was empirically found to be 3.90 Hz using 100,000 trial sets of BFORs. This is in agreement with the theoretical value of 4.35*SQRT[ (5-1) / 5 ] = 3.89 Hz. The second factor in this equation is the reduction in the population standard deviation to the sample standard deviation. When we have a limited number of samples, there is a bias to a lower expected value than the population sigma. The standard deviation of the sample BFOR standard deviation was found to be 1.73 Hz. Then, using the equation above, I find Z and then the percentile P.

Using this method, the RMS errors in the percentiles from 1%-99% is low, being only 0.7%. Thus, my statistical model for the BFO standard deviation is accurate over the range of percentile values of interest.

3. The next two classes of analyses deal with correlation coefficients – those with zero expected value and those with a non-zero expected value.

Recall that the Pearson correlation coefficient r is given by:

r = S_xy / (S_x * S_y) = [SUM(xy)/N] / SQRT{ [SUM(x^2)/N]*[SUM(y^2)/N] }.

When the expected value of r is zero, the correlation coefficients are analyzed statistically using Student’s distribution, employing the t transformation:

t = r*SQRT[(N-2)/(1-r^2)],

where N = 5 pairs. The number of degrees of freedom is thus N – 2 = 3. Now “t” is approximately normally distributed, and the percentiles are found using the two-tailed cumulative Student’s distribution with 3 degrees of freedom. In EXCEL, this is:

P = T.DIST.2T[ABS(t),3].

Note the absolute value of t is used, since we don’t know the expected sign of t, and we must allow for both the positive and negative tails.

Using 600,000 sets of 5 pairs of uncorrelated random values, I get an expected value of -0.0009 (i.e., zero) and a standard deviation of 0.5005 (i.e., 50%) for r. The standard deviation is high because both variables are random and the number of pairs is small. For 600,000 trials of t, I get an expected value of 0.004 and a standard deviation of 1.723. The observed percentiles match the expected fractional percentages within 0.15% RMS for percentiles from 1% to 99%, so the statistical model is actually quite accurate. This method of analysis applies to those correlation coefficients which have an expected value of zero, which are # 6-9, 11, & 12 from the list above.

4. For the two autocorrelation cases of BTOR w.r.t. BTOR and BFOR w.r.t. BFOR, N = 4 (pairs) and the expected value is not zero. This applies to the statistics #4 and 5 in my list above. Using 200,000 random trials for this case, the expected value of r was mu_r = -0.237 (i.e., -23.7%) and the standard deviation was sigma_r = 0.446 (i.e., 44.6%).

Fisher’s F transformation is used in this case to obtain an approximately symmetric normal distribution from the asymmetric r distribution:

F = (1/2)*ln[(1+r)/(1-r)] = arctanh(r).

Due to the nonlinear transformation, the mean of F is slightly different than the mean of r (mu_F = -0.311).

Next we find the normalized Z-score:

Z = [F – mu_F] / sigma_r.

Note that in the equation above for Z above I use sigma_r, not sigma_F, because I found this substantially improved the accuracy of the predicted percentiles. The percentile is then found from the Z statistic using the two-tailed cumulative Student’s distribution (the same as in the zero-mean case above):

P = T.DIST.2T[ABS(Z),3].

The number of degrees of freedom in this case is N – 1 = 3 with N = 4 pairs of variables. The observed percentiles using 200,000 trials matched the expected percentages within 0.7% RMS from 1%-99%. The predicted percentiles with non-zero mean r are not quite as accurate as the zero-mean r case because the r distribution is asymmetric. Two transformations (F and Z) are needed to obtain an approximately symmetric distribution with the correct shape to match a standard distribution (like normal, chi squared, or Student’s). Still, the accuracy is more than adequate for the problem at hand.

Combined Percentile

Once the P-values for all 12 statistics (10 in the case of LNAV) are calculated, the last step is to combine them into a single percentile estimate. Fisher’s method of combining percentiles first finds chi squared:

X^2 = -2*SUM[ ln(P_i) ]

The number of degrees of freedom which is compared to chi squared is twice the number of statistics (2N = 2*10 or 2*12 depending on the lateral navigation method). Finally, the combined percentile is found using the chi-squared distribution. In EXCEL:

P = 1 – CHISQ.DIST(X^2, 2N, 1).

Again, the (combined) P-value is the percentage of random trials, assuming the route is True, that would be expected to fit the data worse than the current route. One can think of the P-value as being the probability that the route is True, and ratios of P-value therefore represent relative probabilities that the route is True.. The combined percentile is used in my objective function and is maximized by my route fitter. The expected value for the combined percentile is 50% for the True route. Half the trials would fit worse, and half would fit better. A combined P-value above 50% can occur half the time. If a fit has a P-value well above 50%, that implies either that (a) an additional degree of freedom in the route model (beyond the seven minimally required) is being fitted (thereby artificially reducing the residuals), and/or (b) the MH370 Inmarsat data have somewhat smaller-than-average scatter. To test this situation, I have embedded a means to inject random BTO and BFO reading errors into my route fitting program. When I do that for a fairly large number of trials using the one best-fit route (LNAV 180 through BEDAX), the average combined P-value is close to 50%. From this result I conclude that the excess in best-fit combined P-value (it is close to 80%) for that one route using the actual MH370 data is more likely to be caused by the actual MH370 data set than by over-fitting the route.

]]>Modern inertial reference systems are good for about 30nm of error over an 8 hours flight without GPS aiding. A 30nm position error would have a negligible effect on Doppler compensation.

]]>@TBill stated “Nederland and I both feel there seems to be a possible nominal “low and slow” 400 knot path from Arc4 (near BEBIM) to NZPG.” and “Admittedly I and Nederland would welcome further IG review of that proposal.”

In your linked paper, you state “it appears that MH370 could have instead flown due south, perhaps from BEDAX to BEBIM, in effect taking a shortcut down to the flight sim pathway” and “working backwards from Arc7 suggests waypoint BEBIM might have been the focal point for the pilot to change heading to fly towards McMurdo Station (NZPG), assuming an approximate 400 knot ground speed.”

You describe the test flight conditions that you applied:

Atmosphere: Set to 80 deg F at Sea Level

Winds: 0

Altitude: FL250 = approx. 25,000-ft

Heading: 168 deg South (True)

Ground Speed: 400 knots

True Air Speed: 400 knots = Mach 0.65

Indicated Air Speed: 275 knots

Flight Path: ISBIX to BEBIM to 78S67 (NZPG)

(1) BEDAX is at longitude 93.787575°E, ISBIX is at longitude 93.675108°E and BEBIM is at longitude 93.835000°E, so this route is not quite due south. I took waypoint BEBIM for the turn to NZPG, which I estimate was reached at 21:26:45 UTC.

(2) NZPG is at -77.963333°S 166.524444°E, which is close to your 78S67 waypoint. The initial bearing from BEBIM to NZPG is 168.12019548°T (Vicenty).

(3) FL250 at your surface temperature of 80°F (26.7°C) and a surface pressure of 1012 mB gives an air pressure at FL250 of 376.0041 hPa and a geometric altitude of 25,986 feet.

(4) I applied your Mach 0.65, but included the effect of air temperature and winds at FL250. In order to reach your latitude of 28.911°S at 00:11:00 UTC precisely, I slightly reduced the Mach after waypoint BEBIM to 0.642856.

The BTO and BFO results are excellent. My only concern is the high PDA at 00:17:30 UTC of 3.861% (nominal 1.5%), which represents around 1,470 kg fuel remaining at MEFE.

Here is a link to a detailed flight path report:

]]>Does the coriolis pseudo force get felt by say a micro mechanical accelerometer?

In the case of MH370 the GPS apparently corrects the IRU with notional accelerations.

However if the GPS were somehow disabled by the pilot and if the IRU actually did drift then the pre-comp calculation could be off.

]]>I look forward to your (collective) forthcoming paper that describes your method for generating and evaluating each path versus the particle filter Monte Carlo approach taken by BSTG as described in their book.

It seems that you select an exact navigation model and setup with maybe random winds aloft and then evaluate that profile using the arc crossing data to assign a probability for that model.

I had issues with the dynamic model used by DSTG to generate the “infinite” flight paths. Although I assume their PDF for the “infinite” flight paths may bear some relationship to the more likely explicitly programmed paths in your set of cases.

@DennisW noted “An active flight path can always be created that is a better fit. That is not the point of the exercise.”

“I still wonder whether one simple profile could exist where an active pilot could have flown to fuel exhaustion north of 25 S on arc 7 and “perfectly” met the arc crossing data constraints. Maybe it is not remotely possible?

]]>Thank you for your kind offer, but what you are suggesting has already been done. Bobby, Victor and I have performed a systematic study during the last 4 months of all possible flight paths and are soon to publish the results.

In total 1,372 flight paths have been analysed, of which 828 flight paths since the start of this systematic study on 17th February 2019. Start latitudes from 16.0°N to 4.3°S have been covered and the start longitudes were unconstrained. Start times from 18:41:00 UTC to 19:32:00 UTC, but the final major turn had to be completed before the 2nd Arc at 19:41:03 UTC was reached.

Systematic initial bearings from 155°T to 195°T in steps of 1°T were analysed, plus some exotic cases in steps of 0.1°T. All navigation methods were : LNAV, CTT, CTH, CMT and CMH, all speed modes: Constant Mach 0.80 to 0.85, LRC 0.7047 to 0.8408, MRC, ECON CI52 and all flight levels: from FL290 to FL430. The fuel endurance was allowed to vary around 00:17:30 UTC and the resulting PDA was noted. The PDA was allowed to vary from the nominal 1.5% and the possibility that the bleed air was shut off for part or all of the time was considered.

You may have seen in the comments above, that I have in addition run a number of candidate flight paths from @TBill, @Niels and @Hank.

]]>@TBill stated “@Richard Nederland and I both feel there seems to be a possible nominal “low and slow” 400 knot path from Arc4 (near BEBIM) to NZPG.” and “Admittedly I and Nederland would welcome further IG review of that proposal.”

@Niels stated “@Richard I have optimized “case C”. It has a much straighter track after 21:11 (more than ten times smaller variance) compared to “case A” and “Could you perhaps help to evaluate the proposed route (21:11:02 onwards)?”

I have noted both requests and will get to running the flight paths suggested through my model in the coming week.

I am very busy at the moment, helping to prepare the next paper that Bobby, Victor and I will publish here soon, describing the wide area scan of the Southern Indian Ocean.

]]>@DennisW

@Victor Ianello

@Richard

I have effectively limitless computing capacity at my disposure for about three months. I just want to throw this model at everything that, no matter how unlikely, could potentially have happened and rule out 99.99% of the ridiculous flight paths and EOF locations. Please, let’s just get it done?

]]>How is the coriolis pseudo force handled by the different navigation methods?

Compensatory trim would increase fuel usage. Is this incorporated into the fuel model?

]]>Interesting, I’ll check more in detail. I already noticed it passes quite close to waypoint BEBIM (which is at -10.645, 93.835). ]]>

Interesting that your case “C” LRC track above leads direct to waypoint EKUTA -39.843334° 95.000000° ]]>

I have optimized “case C”. It has a much straighter track after 21:11 (more than ten times smaller variance) compared to “case A”. This comes at the cost of a slightly worse fit to LRC speed mode. It is still based on an assumed constant shift in bias frequency (to 151.5 Hz)

Could you perhaps help to evaluate the proposed route (21:11:02 onwards)?

The key parameters:

LRC to fuel exhaustion

FL 335.3

21:11:02 position of -9.191, 93.692 (11 km)

Constant track after 21:11:02 of 178.098 degrees (based on the average track over the 21:11 – 00:19 interval)

*I am having trouble seeing how active flight paths might not be better fit.*

An active flight path can always be created that is a better fit. That is not the point of the exercise.

]]>I sort of agree with Rob’s sentiment that the most valuable contribution could be a model itself that could be used to gauge possible paths. Of course, if you have a clear definitve flight path answer, go with it. But I am having trouble seeing how active flight paths might not be better fit.

Also I am perhaps guilty of under-estimating the importance of the Atlantic article, which I need more time to review (tied up at the moment). But I think he is agreeing with me on active flight with active descent at end, think he is saying howver, intentional dive to blast aircraft into tiny bits, which implies close to Arc7 maybe 20-25 South due to active pilot, or maybe we missed due to small size of debris.

]]>For the record, I fully expect the long list to be whittled down to an incredibly short list. But I want the numbers – all of them – down to the inch, if possible.

]]>Don’t know the answer relative to OI compensation, but it seems unlikely that it will be pledged by Malaysia. LANGEWIESCHE makes the point several times in the Atlantic article that Malaysia simply wants the whole issue to go away.

]]>In my view, the more important question is, if Ocean Infinity decide to go back and search, will the Malaysian government support their move and recompense a successful mission?

]]>I still think it is significant that the very early stages of the MH370 diversion were “managed” by high level government officials, and not the usual resources assigned for that purpose. Even ICAO commented negatively on that activity.

]]>“Maybe he confused the transponder with SDU log-off records.”

The translator actually said “communications” so we do not know if Jiang was talking about Transponder, SATCOM, or radios. But the important point is that it certainly was possible for the MH370 pilot to manually turn off all communications without any warning signals.

]]>If Malaysia is incapable of assigning blame for the downing of MH17 where there is abundant evidence, how can we expect it to make reasonable conclusions and take reasonable actions regarding MH370, where there is less evidence?

Now in the news: *Malaysian Prime Minister Mahathir Mohamad said there’s “no proof” Russia is to blame for the 2014 downing of Malaysia Airlines Flight 17 over eastern Ukraine.*

*“We are very unhappy because from the very beginning it became a political issue on how to accuse Russia of the wrongdoing,” he added. “So far there is no proof. Only hearsay.”*

Due to the voice-over, I can’t hear Jiang’s original words (whether he said “transponder” or something else). I’ll let him know. Maybe he confused the transponder with SDU log-off records.

]]>Here is what I saw:

https://www.youtube.com/watch?v=YhxJ4hLth64

At 4:45 minute mark (according to the translator) Jiang Hui says that he believes turning off the transponder, manually by the pilot, sends an OFF signal (presumably to ATC). The fact that this “Transponder OFF” signal was not received from MH370 suggests there was an apparent mechanical issue (which cut off the transponder).

That statement made an impression on me because, I personally wonder if something like “Transponder OFF” signal might be a good thing to have in the future.

]]>I will see if I can find it… ]]>

Ha? Can you please provide the link to the interview? Because I happen to know the Chinese NoK member who attended the 5th anniversary event in Kuala Lumpur, and I can’t believe he said that. What I know is that, he taught himself a lot technical details in order to gain an understanding of the event. Could it be wrong translations?

]]>I noticed at the 5th anniversary, a TV interview with I think the only China NoK who attended, the NoK said he had learned it was impossible for the pilot to turn off the transponder, so that’s why he knows the pilot did not do it. That was when I realized there was a disconnect. ]]>

Most people focused on 1) what ALSM was quoted as saying he believed the plane climbed up to 40,000 feet to accelerate the effects of depressurizing; and 2) what the anonymous “lifelong friend” of Zaharie’s had to say about his personal life.

Now, I understand the methodology Mike and other IG members used to reach the 40,000~43,000-feet conclusion, but did he really tell Langewiesche he thought the purpose was to accelerate depressurizing? Or was it another misquotation?

]]>Najib has been out of office for over a year now. The new administration has already not done better in my view. Frankly, I think we have gotten all we are going to get from Malaysia. Different players same results.

]]>“Langewiesche has forgotten more than I’ll ever know about airplanes. The article is a compelling, heartbreaking read, and I suspect he’s right about Zaharie. But his portrayal of an entire political system as incorrigibly dishonest does not serve the interests of good analysis.”

The Malaysians hid, misled, and misinformed throughout this investigation. Whether or not the new administration does better remains to be seen.

]]>Here is what appeared in the article:

*Of all the profiles extracted from the simulator, the one that matched MH370’s path was the only one that Zaharie did not run as a continuous flight…*

Here is a portion of an email exchange with a fact-checker, who asked me to comment on this statement:

Fact checker: Of all the profiles on the simulator, the profile that matched MH370’s path was the only one that was not run as a continuous flight. Instead he had advanced the flight manually in multiple stages, subtracting fuel as he proceeded until the fuel was gone.

My response: We only have access to the flight files that were recovered from the Volume Shadow of drive MK25, so we don’t know how other sessions were conducted. It is true that the user “advanced the flight manually in multiple stages, subtracting fuel as he proceeded until the fuel was gone.”

]]>In Clive Irving’s piece in The Daily Beast, he brushes off the theory that the captain was responsible for the diversion because official statements and other reports say otherwise.

In an article in the **Malay Mail**, former Malaysian minister Hishammuddin Hussein says that Langewiesche’s allegations are false, and his allegations can be debunked by authorities.

I have no reason to question the good work done by you, DrB, and others regarding a passive pilot from 19:41. A

LNAV 180 to cross arc 7 at 34.3 S is similar to the independent DSTG model with center at 38 S. These are directly associated with searched areas but debris could have been missed. All good work for an inactive pilot and there are good reasons why this may be true. I don’t question this model.

“Not much wiggle room” is not zero. I am NOT promoting an active pilot. It just seemed to me by looking at the NE-SW arc orientation that ground speed could be slowed at cruise airspeed by maneuvers and by probable accident the arc crossings would be met. Just dumb luck on a SE course. You indicate arc 7 can be limited to 17S to 39S so I was just thinking about how you get to the northern sectors and fit the SAT data. The duration is also key because you can’t cross arc 7 with lots of fuel at the NE sections.

It seems the IG has simulated viable flights to the NE sectors, which I was not aware.

]]>I really appreciate the work Bobby, you, and Victor have done recently (and previously). I liked your drift analytics a lot, and used them to conclude 20S was the Northern likely limit of terminal latitude.

If one uses simple logic to assign an equal probabily to terminal locations between 20S and 39S you can infer (using a 10% probabilty that the wreckage was missed) that there is a 90% chance the aircraft is in the 20S to 25S latitude range. I still do not want to consider areas beyond the current search width.

We have all seen this movie (analytically biased searching) before. I would be hard for me to do addtional searching below 25S until the 25S to 20S region has been searched.

]]>Theoretically MH370 could have ended anywhere near the 7th Arc between 17°S and 39°S.

I appreciate that some people believe that the drift models may suggest a more northern location. I was one of them:

Fortunately, Bobby came to our rescue and showed that there is a wide range of possible MH370 end points that fit the drift analyses between 20°S and 35°S, some more likely than others. I no longer believe that the drift models are able to pin down the MH370 end point.

For any given flight path, there is also not that much wiggle room to separate fuel range and endurance with manoeuvres and match the satellite handshakes between 19:41:03 UTC and 00:11:00 UTC as well as fuel exhaustion at 00:17:30 UTC between the 6th and 7th Arc.

]]>I wouldn’t put too much weight on the FBI’s reply to me. It could be that at this point they can’t prove it was NOT a criminal act, so the case remains open, and releasing information would only hamper ongoing and future efforts.

I’ll add that on a single day, I submitted two FOIA requests related to MH370. One was on the subject of the simulator data, and the other was related to another aspect of the disappearance. The FBI lumped the two requests into one and replied with the letter I shared with the subject “Malaysian Airlines Flight MH370”. I suspect that ANY FOIA request related to MH370 gets the same response.

]]>I did not mean to suggest the impossible. The problem I am posing is how do you fly at cruise airspeed at FL 350 from the assumed position at 19:41 and exhaust fuel at arc 7 above 25 S and meet all of the SATCOM constraints. This assumes s-turns or circles. Out of the infinite random possibilities it would seem one wiggly path could be found that met constraints and splashed above 25 S. I am not suggesting complex planning – just a result of some random maneuvering to decouple duration and range.

If a pilot assumed searchers would eventually figure a cruise start position at 19:41, he would also know for any course that a range line could be drawn E to W with some uncertainty. Any delays by holding or S-turns would widen the E-W band.

I have no reason to question this being a ghost flight on LNAV. This was the basis for the DSTG particle filter model and more recent work. Because some people believe that drift models may suggest a more northern location I questioned whether it is feasible (not likely) for a maneuvering flight path that meets all SATCOM constraints to exist.

Maybe it is not possible and the aircraft absolutely is located below 30S. And I am OK with that.

]]>Thank you for attempting the FOIA request. 10-bonus points for you.

Sounds like both USA and France (and others) are withholding MH370 info due to potential criminal act. By itself that says something. Seems like we ought to be able to ask, if that is true, what is the suspected crime? And why is it valid for Countries to hold that information indefinitely as a state secret? I am aware there is a possible (supposedly June_2019?) MH370 court case in Malaysia.

@Richard

Nederland and I both feel there seems to be a possible nominal “low and slow” 400 knot path from Arc4 (near BEBIM) to NZPG. @Nederland has actually published two versions of this path, one to NZPG, and his second path goes to WYKS. To accomplish that, MH370 woould presumably need a slow down at approx. BEBIM.

Nederland saw it first and published before me, so he gets any credit. I later indepedently noticed that ASTB’s early “low and slow” red flight path is almost identical to the ending of the home simulator path, is how I found it. Admittedly I and Nederland would welcome further IG review of that proposal.

My write-up is here:

https://twitter.com/HDTBill/status/1043496105252655105

I apologise, I am obviously not communicating what I want to say very well.

In order to fly a path between an Initial Bearing of 160T and 170T at a cruise altitude around FL350 and meet the ping rings, the average Ground Speed needs to be between 459 knots and 482 knots.

The distance between 19:41:03 UTC and 00:11:00 UTC for FL350 is 2115.6 NM, which implies an average GS of 470.2 knots.

If you lose 500 NM through circling, then the rest of the flight has to be at around 600 knots to meet the ping rings.

A Ground Speed of 600 knots is simply impossible for MH370.

]]>I suspect that this is a standard response for any FOIA request related to MH370, and not just for information related to the simulator data. As the disappearance may be due to criminal activity, and as there are still many unknowns, it is not surprising that the FBI chose to protect all data related to MH370.

]]>Thanks for your response.

The DSTG model is reasonable for a ghost flight scenario. Even the infinite fuel assumption with post correction is not bad with no pilot to mess with intentional holding. LNAV 180 may have been programmed. I also can accept a undersea search could have missed wreckage. I have no reason to challenge any of the inactive pilot work.

My only point is what could an active pilot do to mess with the post simulation with no knowledge of SATCOM pings. If a pilot engaged LNAV 180 but broke off every hour for a 20 minute circle at cruise the plane would crash 500 miles or so early. Of course this would fail to meet all of the arc crossings and BFO/BTO data. The only feasible routes to reach arc 7 with 500 or so less miles is a more SE route such as the 167T. I will look at the links when I am at my PC.

Because there are infinite ways to have flown with holds it is possible that some combination could exactly meet the metrics. I think if you picked a specific end point you could construct a maneuvering profile that would fit the model. That does not mean it was followed – just possible. The problem with active pilot is too many option for route and water entry.

I have no reason to assume that there was a live pilot after 19:41. But I can’t rule it out either – who knows?

Thanks for the discussion.

Hank

]]>