In last month’s New York magazine article about Zaharie Ahmad Shah’s flight simulator, I cautioned against treating the recovered data as a smoking gun:
…it’s not entirely clear that the recovered flight-simulator data is conclusive. The differences between the simulated and actual flights are significant, most notably in the final direction in which they were heading. It’s possible that their overall similarities are coincidental — that Zaharie didn’t intend his simulator flight as a practice run but had merely decided to fly someplace unusual.
What I failed to question was the report’s assumption that the six points all belonged to a single flight path. On closer examination that assumption seems ill supported. Rather, it seems more likely that the six points were recorded in the course of two or possibly three separate flights. They were interpreted as comprising a single flight only because together they resembled what investigators were hoping to find.
The first four points do appear to show a snapshots from a continuous flight, one that takes off from Kuala Lumpur and climbing as it heads to the northwest. Between each point the fuel remaining decreases by a plausible amount. Each point is separated from the next by a distance of 70 to 360 nautical miles. At the fourth point, the plane is at cruise speed and altitude, heading southwest in a turn to the left. Its direction of flight is toward southern India.
The fifth and sixth points do not fit into the pattern of the first four. For one thing, they are located more than 3,000 miles away to the southeast. This is six or seven hours’ flying time. Curiously, at both points the fuel tanks are empty. Based on its fuel load during the first four points, the plane could have flown for 10 hours or more from the fourth point before running out of fuel.
The fifth and sixth points are close together—just 3.6 nautical miles apart—but so radically different in altitude that it is questionable whether they were generated by the same flight. To go directly from one to the other would require a dive so steep that it would risk tearing the aircraft apart.
The picture becomes even more curious when we examine the plane’s vertical speed at these two points: in each case, it is climbing, despite having no engine power.
The ATSB has speculated that in real life MH370 ran out of fuel shortly before 0:19 on March 8, and thereafter entered into a series of uncontrolled porpoising dives-and-climbs called phugoids. In essence, a plane that is not held steady by a pilot or autopilot, its nose might dip, causing it to speed up. The added speed willl cause the nose to rise, and the plane to climb, which will bleed off speed; as the plane slows, its nose will fall, and the cycle will continue.
Could a phugoid cause a plane to climb—663 feet per minute at point 5, and 2029 feet per minute at point 6? The answer seems to be yes for the fifth point and no for the sixth. Reader Gysbreght conducted an analysis of 777 flight-simulator data published by Mike Exner, in which an airliner was allowed to descend out of control from cruise altitude in the manner that the ATSB believes MH370 did.
A diagram produced by Gysbreght is shown at top. The pink line shows the plane’s altitude, starting at 35,000 feet; the blue line shows its rate of climb. Worth noting is the fact that the phugoid oscillation does indeed cause the plane to exhibit a small positive rate of climb soon at first. But by the time the plane reaches 4000 feet — the altitude of the sixth point — the oscillation has effectively ceased and the plane is in a very steep dive.
Gysbreght concludes:
As expected for a phugoid, the average rate of descent is about 2500 fpm, and it oscillates around that value by +/- 2500 fpm initially. The phugoid is apparently dampened and the amplitude reduces rapidly. I was slightly surprised that it reaches positive climb values at all. Therefore I think that 2000 fpm climb is not the result of phugoid motion.
Not only is the plane climbing briskly at the sixth point, but it is doing so at a very low airspeed—just above stall speed, in fact. If the pilot were flying level at this speed without engine power and pulled back on the controls, he would not climb at 2000 feet per minute; he would stall and plummet. In order to generate these values, the plane must have been put into a dive to gain speed, then pulled up into a vigorous “zoom climb.” Within seconds after point six, the simulated flight’s speed would have bled off to below stall speed and entered into an uncontrollable plunge.
Perhaps this is why Zaharie chose to record this particular point: it would have been an interesting challenge to try to recover from such a plunge at low altitude.
What he was doing at points 5 and 6, evidently, was testing the 777 flight envelope. This might seem like a reckless practice, but I think the opposite is the case. From time to time, airline pilots do find themselves in unexpected and dangerous conditions. For instance, as Gysbreght has noted, “On 7 october 2008 VH-QPA, an A330-303, operating flight QF72 from Singapore to Perth, experienced an In-flight Upset west of Learmonth, West Australia. The upset was caused by a freak combination of an instrumentation failure and an error in the flight control software, which resulted in an uncommanded pitch-down. The vertical acceleration changed in 1.8 seconds from +1 g to -0.8 g.” It would be better to experience a situation like this for the first time in a flight simulator in one’s basement, rather than in midair with a load of passengers and crew.
What Zaharie clearly was not trying to do was to fly to McMurdo Station in Antarctica, as some have speculated.
For one thing, while a 777 is fully capable of flying from Kuala Lumpur to Antarctica, it was not carrying enough at point 1 to make the trip. And if one were trying to reach a distant location, one would not do so by running one’s tanks dry and then performing unpowered zoom climbs.
The misinterpretation of the flight simulator data offers a couple of cautionary lessons. The first is that we have to be careful not to let a favored theory color our interpretation of the data. The investigators believed that MH370 flew up the Malacca Strait and wound up in the southern Indian Ocean, and they believed that Zaharie was most likely the culprit; therefore, when they found data points on his hard drive that could be lumped together to form such a route, that’s what they perceived.
A second lesson is that we cannot uncritically accept the analysis made by officials or by self-described experts. Science operates on openness. If someone offers an analysis, but refuses to share the underlying data, we should instinctively view their claims with suspicion.
@Richard
Thanks for revisiting the issue in your last post. I feel like I have been beating this to death, and that my comments are no longer welcome or at best are tolerated with eyes rolling.
Figure 5.4 of the DSTG book has been very troubling to me since I first saw it – troubling for a lot of reasons.
1> Why publish the data in the first place?
The ATSB surely knows by now that there are a lot of smart people following this event with keen interest. They had to know that figure 5.4 would be very unsettling relative to the entire search strategy. The fact that it has not been unsettling is astounding to me. It changes things a lot. Where are the howls of indignation?
2> Not attributing the BFO error to a cause.
The DSTG makes some lame statement to the effect that they believe the error has a geographic dependence, but were never able to close in on a relationship. Wow. Talk about tossing more gasoline on the fire. Here you have a significant deviation from a previously stated error bound, and you casually brush it aside, and attribute it to the wrong causality (in my opinion). Am I the only one in geek space who finds this behavior incredibly casual?
3> Data from other flights
If I were with the DSTG I would be bordering on an anxiety attack. I would be hammering at data from every flight I could lay my hands on in an attempt to characterize this anomaly. Nothing of the sort is even hinted at. It is like, oh well, here is some data. We don’t know what it means. Let’s move on with our analysis. WTF?
4> Reaction from the masses.
I would have expected a much stronger reaction from the analytical community outside the SSWG. It never happened. For many months (years now, actually) people have been tweaking flight paths to come within a Hz or so of the ISAT BFO data, and along comes figure 5.4. Either figure 5.4 has to be ignored or we have been guilty of significantly over-constraining our flight paths. Is there any other conclusion?
Jeff,
“In your scenario the disappearance from radar and the SDU reboot would presumably also coincidental”.
No. You saw the plot I presented. This is only one of a number of possibilities. In my scenario re-powering of the left bus was immediately followed by entering holding pattern with descent. The intent could be to jettison fuel, or move to other flight level to minimise possibility of collision, or comminicate via Satcom, or something else. Note that setting constant bank angle is the simplest and probably the only possibility of the automatic “holding pattern” when ADIRU fails.
“Also, I don’t understand why you think I think an FMT occurred at 18:40.”
BFOs 18:40 indicate nearly the same heading as all subsequent BFOs. If you assume that by this time MH370 did not enter its final mode, then the current search area may likely be invalid. However, you insist that the current search zone is not compatible with the “ghost flight” theory. Thus the aircraft must have entered its final mode at around 18:40. We know that the aircraft had different heading at 18:25. So the first call was made at the approximate time of the FMT, within 15 minutes difference. Unless you imply spoofing, when do you think the FMT was performed?
“Dr Bobby is now working to ascertain whether there are any autopilot configurations that could deliver the plane to a point outside the currrent search area”
Why don’t you ask some appropriate specialist or experienced pilot, perhaps from Boeing?
@jeffwise said, “My source for all that was Victor himself, who as he has said here publicly by now, has seen all the secret Malaysian police documents. Perhaps he will jump in and clarify.”
I have no idea what public statement you are referring to in which I said I have seen all the documents. Unless you find one, please correct your statement. Here is actually what I said:
Second, Le Monde’s Florence de Changy shared with me portions of the Malaysian criminal report before she wrote her article. The two pages that Jeff published here were also from Florence’s material. That is why I was able to confidently say that Jeff’s material was authentic. That doesn’t make me a conspirator in a smear campaign against Zaharie, as some have claimed.
http://jeffwise.net/2016/08/12/did-mh370-plunge-or-ditch/comment-page-2/#comment-180011
In fact, I know for a fact there are major portions of the report that I have not seen.
@Matt Moriarty; @others:
It seems I turned into a celebrity while I was away…
Death threats is not what I do, so you are right. I thought the modifier wasn’t dangling in that particular respect.
What I was trying to convey was that you should respect the living conversation among longtime members here, and that it is no point in referring to an idealized would-be reality as a substitute for what is actually going on in right now. It is manners and it is a question of (to a large extent) different orders.
I wanted to point to the fact that you in effect claimed to prefer (spending your time with) what is qualitatively an artifact, a redacted and commodified text (the two-way-communication abilities of which, and your place among these, remains to be realised) over the de-facto living (internet) conversation (as I assume this is, predominantly, for the time it lasts) already instituted here.
Texts (articles and books by scholars and journalists) are naturally good for many things. But from the point of view of conversation and community, texts belong to the paraphernalia you bring to enhance it or make it thrive and produce. You can admire an armchair, a throne or (a) stool, you can learn things, pick up norms and ideas, and styles and knowledge, but you cannot speak to it for very long. It is an inanimate object. And the deader it is, the easier is it redacted, abriged and commodified to meet with expectations of admirability (hence “being dead”). Don’t mistake the author (the commodified/-yable brand name) for the individual, if you like. The one is missed when s/he dies, the other has never felt better.
That was unexpextedly difficult. A one-timer, I promise.
Science is about sticking to known facts. IMO technical failure – if it happened – is such a remote possibility that pitching for that 0.01% seems utterly pointless. Once tunnel vision sets in it’s hard to keep an open mind. For this reason I am surprised at the focus on Zaharie only. Are people saying that the co-pilot would not have been capable enough to do the same? IMO, he would have. Actually, one might construe the entire flight path as sloppy work, if it were intentional. Just saying. The simulator data points, are interesting and basically confirm it was not a single simulation. In any case, it may have no relevance at all to what actually happened to MH370. Just, coincidence. Looking for reasons, if they are at all apparent, why anyone would commit suicide in this fashion, is a tough call to make. Ask all the people who are clueless, years after the fact, as to the “why” of it all. You can try and look for a reason, but likely will not find it. Perhaps, to protect life insurance? Perhaps to protect people you care about and hide the suicide? Perhaps to safeguard widow pension? This is Malaysia after all. Perhaps because it was a very personal act for personal reasons? IF it was intentional, SIO is the place to be, if you wanted people to keep guessing and never find this plane.
@Trond:
Search for “Arlanda MAS incident” or similar and hit images.
@Oleksandr:
If you scroll down on wikipedia’s 777 page you will find maximum landing weight specs for the triple-7 variants.
Perhaps you can use that to get an idea if mh370 needed to jettison fuel to land at all or if it would merely try to do it as a courtesy (extra safety precaution) to the passengers (which then could be assumed to be alive and well at that point). If you catch my drift. I am then assuming that there might be different rationales behind dumping or trying to dump at different moments. With a plane more or less in order but the passengers dead you might assume that the pilotes could expect to take down the plane safely if within maximum landng weight — and all variants of that. But if you have a very serious condition with the aircraft (but perhaps not open fire) you would perhaps expect them to dump right away, without any thought of where the fuel might fall down. Perhaps this has been treated before.
@Ge Rijn
Interesting point and approach for clarity. Which of the following would you consider to be potential debris probably overlooked:
1.http://tuoitrenews.vn/society/33337/vietnam-district-chairman-denies-statement-on-mh370-debris-discovery-newspaper
2.http://www.nst.com.my/news/2016/01/124755/liow-debris-found-besut-not-mh370
3.http://www.dailymail.co.uk/news/article-3416845/Malaysia-confirms-Thailand-debris-not-MH370.html
All three were found in the vicinity of IGARI at different times.
@Jeff
Sad to see you allowed a comment from @Brock through unmolested considering it was an ingenious rehash of my banned SCS:
“The timing, location, and number of debris finds is more rationally explained as either planted (we’ve yet to reconcile the flaperon’s barnacles to its buoyancy) or escapees from containment efforts (prevailing currents from IGARI seem to run S, then SW through Sunda Strait to the IO, and eventually WSW toward Africa) than as what one would expect from a high-energy impact anywhere on the 7th Arc.”
I am all for @Brock having his say. He has been to me, a top notch contributor in more ways than one……but fairness @Jeff….fairness 😀
@Johan
Thanks for that…uhh…explanation. I’m crystal clear now?
@Victor
I never saw you claim to see “all the Malaysian police documents.” But I’m starting to understand Jeff’s behavior. Sorry, man.
The loss of any outside parts near IGARI might increase drag as would an “erratic” flight (one with many turns) so wouldn’t endurance be affected? IOW, could it have flown for almost six hours after last radar on a zig-zag course after FMT and/or with external damage? I do not think so.
@Bobby: thanks for your thoughts – and for your latest paper, which I read with keen interest, as always.
Interesting that you can fit the BTOs with both a fixed track at 500 KTAS or a fixed heading at 450 KTAS (per my read of your seminal and latest recommendations, respectively). This implies winds in your model happen to add exactly the curvature required to make a slower path fit.
1) to within BTO error tolerances, is this a fair description? Please confirm or correct.
2) if fair, then a) that’s quite a coincidence, and b) is it even an accurate portrayal of winds that night? For example, how do you square the slightly east-curving pattern of your new proposed path between 5 and 20°S to what appear to me to be prevailing WEST-bound winds over the entire course of that segment? See, for example, nullschool data as at 14/03/07 21:00 UTC at 250hPa ~FL(330):
https://earth.nullschool.net/#2014/03/07/2100Z/wind/isobaric/250hPa/orthographic=87.08,-32.13,527/loc=91.873,-17.449
Also: “more than sufficient” fuel to reach Arc 7 used to be a pejorative among experts when applied to impact latitudes in the low 30’s: any path requiring unnaturally HIGH PDA’s were eschewed, because we’ve been led to believe Arc7 is itself an artefact of 2nd engine flameout. If you are now recommending this new path despite indicated PDAs more than double those of your seminal work, I infer you do not consider +4.7% inefficiency to be problematic enough to merit comment…? For example, does this PDA square with recorded PDAs for the early portion of the same flight?
Finally: I’d love to run through as many details on your models generally, and your fuel model in particular. Had you posted a link to the gory details, which I missed? If not, is there any chance you could send me, e.g. The fuel model?
Huge thanks in advance.
@LaurenH
Two aspects to consider, max range and max endurance. Max endurance is achieved at slower speed. To answer your question then would be yes, depending on drag increase. Wether the respective arcs could be reached in time is a different thing, which the number guys probably can answer.
@Matt:
I think you got the gist of it. (Bigger smile than I can manage 🙂 )
I’ll never do that again.
@Brian Anderson,
You said: “ “Magnetic Track (by TRK HLD using the MCP)
Really? Do you have a definitive reference confirming that such a mode is even possible? The only references I have discovered all infer that TRK hold is possible only if the end point is known.”
Really. Here is one:
http://docplayer.net/16287525-B777-automatic-flight-do-not-use-for-flight.html
See the pages (as listed in the document) 9-10, which describe the MCP switch functions. On page 10 it says:
“3 Heading/Track Hold (HOLD) Switch
Push –
• selects heading hold (HDG HOLD) or track hold (TRK HOLD) as the roll mode
• displays HDG HOLD or TRK HOLD on the PFD roll flight mode annunciator”
Also on page 10:
“6 Heading/Track Selector (middle)
Rotate – sets heading or track in the heading/track window and on the PFDs and NDs.
7 Heading/Track Select (SEL) Switch (inner)
Push –
• selects heading select (HDG SEL) or track select (TRK SEL) as the roll mode
• displays HDG SEL or TRK SEL on the PFD roll flight mode annunciator
• the AFDS controls roll to fly the selected heading or track”
No “end point” is required to set a heading or track roll mode using the MCP.
@Wazir Roslan
Thanks for the links.
Two of the pieces I saw before.
The Thailand piece was confirmed to be a rocket piece.
The big Vietnamese wing piece doesn’t fit any 777 part IMO and was never heard of again.
But the Besut-piece I think is interesting.
Not the big chunk in front of the photo but the smaller panel he’s holding behind it.
It is a alu-honeycomb panel.
And Besut is lying on the east coast of Malaysia near the route MH370 took back entering Malaysia again after turning at IGARI.
How they could confirm it was not from MH370 I would like to know.
I wanted to post a dropbox-picture but dropbox seems out of order now in Holland.
I’ll try it later again.
And something akward with the big piece in front of the picture.
There seems to be written 370 on it with big numbers behind the mans head in front of it.
@DennisW, I for one think you raise (or re-raise) a very important point here. The take-home for me is that the search officials who’ve been studying the Inmarsat data have come to the conclusion that the BFO data is 100 percent useless for determining the path of MH370. The error is just too large. This represents a marked shift from 2014, when Inmarsat “solved” BFO analysis (as described in the Horizon documentary) and believed that it would allow them to pinpoint the final resting place of MH370. As late as Oct 2014 they published a report describing a stretch of the seventh arc which minimized BFO error.
Already it was known at the time that BFO was much less precise than BTO, but since then it’s become clear that the uncertainty is much, much larger even than recognized then. So yes, flight paths have been overconstrained, although I think much less so recently.
@ge Rijn
Thanks for responding. Yes I noticed the honey comb to. If you google “Besut MH 370 debris” you will find more images some with barnacles eerily similar to Reunion. But the 370 number does not appear on those pictures. I guess somebody wrote it on for inventory purposes or something. Here are a few looks at it. Notice the colour of the livery:
http://www.nst.com.my/news/2016/01/124652/mh370-investigators-arrive-examine-metal-object-found-terengganu-beach?m=1
http://www.nst.com.my/news/2016/01/124516/besut-village-all-abuzz-over-discovery-metal-object-beach?m=1
http://toknek.com/baca/Objek-Seakan-Serpihan-Kapai-Terbang-Ditemui-Di-Pantai-Besut.html
http://www.thestar.com.my/news/nation/2016/01/29/mh370-team-check-aircraft-debris-in-besut/
I don’t know about you but I suspect the Thai piece is also part of an aircraft as it was found a week before Besut along the same coastline. But that’s my personal opinion.
@Jeff
Thanks for acknowledging my post. I can’t seem to get a reaction from the “cognoscenti”. Yes, it would seem that everyone has quietly shifted their error tolerance without a lot of fanfare. Safe to say that had Victor’s and Richard’s latest flight path appeared before the DSTG Book, it would have been met with some resistance. I think only DrB commented on the BFO residuals in that paper. My sense is that he is still committed to using a smaller number, say 5 Hz or less for acceptable BFO error.
The reality is that there is a much broader range of generally accepted candidate solutions than there was a year ago, and that has not been publicized with any commentary. The DSTG analytics, essentially using BTO only, are handicapped IMO by over-weighting the flight dynamics relative to a straight paths. Which is similar to the handicap imposed by the earlier AP/BFO constraints.
So where does that leave us? We have much less confidence among the analysts in Inmarsat derived terminal probabilities, and need to carefully include other observables, namely the drift studies done to data, and the refined drift studies in progress. JMO.
In the meantime the ATSB has put blinders on and is committed to finishing the established search area. I suppose that is a good box to check, but I am not very confident that they will find the aircraft.
FREE THE DATA Please
Starting at 5:37 in Part 1 of the 60 minutes Australia report, Announcer Ross Coulthart states “this confidential analysis of captain Zaharie’s home flight simulator reveals evidence the captain tried to hide by wiping his hard drive.” A printed page with the data deleted from (and found) on the shadow drive is shown.
https://www.youtube.com/watch?v=ZQHl5SmA08A
An earlier (4/3/2014) report on salon.com also states data from the simulator had been wiped.
http://www.salon.com/2014/04/03/malaysia_airlines_flight_mh370_update_fbi_completes_examination_of_pilots_flight_simulator/
So, it seems Zaharie not only deleted the 6 points from the shadow drive, but also wiped the main drive around the same time in February.
@Aunt Bea
There is nothing (that I can find) in your links to suggest that anything but the six points had been deleted. Please clarify.
@Aunt Bea
I see nothing in your links that supports your statement “also wiped the hard drive”. Please clarify.
correction
“hard” above should read “main”
@DennisW
Working from your points on the BFO accuracy issue:
1> The official reports have never attributed any great precision to the BFO data. The 2014 ATSB report attributing a 1 sigma accuracy of 5Hz, plus a bias offset error of 5Hz, the 2014 Inmarsat paper stated an error of +/-7 Hz (1, 2 sigma?), though figure 15 of that paper might indicate a smaller (1 sigma) error. Anyone who has used smaller errors since late 2014 has been working outside the declared accuracies.
2> DTSG say they found some correlation of BFO error with geographical position – as such that is a statement of fact, though of course correlation does not mean causation. One of the largest two contributions to the BFO is the correction calculated by the AES which very much uses position of the aircraft, so a correlation with position would be possible if that calculation was incorrect in some way. The DSTG report says that the cause of the error could not be tracked to any systematic factor, but after some work.
3> I agree that the DSTG report is short on data from the validation flights, to the point that they reused the same flights with different sampling factors. The report refers to data from the previous 20 flights of 9M-MRO, but why not 100?
4> The official search pursued the data optimisation models well into 2015 so the usability of the BFO data for ‘precision’ location was open for some time. We haven’t seen the BFO errors from all 20 flights, just the two in the Inmarsat and DSTG papers. Possibly there is a wide range of errors across the individual flights which made it difficult for the official search to come to a conclusion. Without all the validation BFO data, external observers are speculating if they use small errors.
@Jeffwise
To be fair to Inmarsat, their October paper indicated an example track – it didn’t claim to be the best fit to the data. At the time there was hope that extensive analysis of the BFO data, even with its errors, could lead to a reasonable length of the 7th arc to search. It was another year before that type of modelling was dropped.
@David, re: “what is Fugro really claiming?”
Fugro claims 100% chance of success, given it is there to be found. E.g.:
“So the areas we search we know 100 percent that if we run over an airplane we’ll know for sure.”
From: http://www.watoday.com.au/wa-news/confidence-increasing-in-the-search-for-mh370-20141001-10ota2.html#ixzz3Et6QbT1F
Kennedy is quoted making similar assurances in an interview transcript I found on the ATSB’s own blog, which I couldn’t quickly find, but which I’ve posted to this forum previously.
@DrBobby,
I am aware of this and similar references to the functions of the MCP switches. But, I fear that you are applying your own interpretation of the functionality. The reference does not explicitly state exactly how the roll modes are implemented in software.
In fact the descriptions must be read and understood in the context of an operational crew flying normal, often prescribed, procedures. You cannot take these statements out of context and then apply your own meaning of specific words in another context.
The term TRK has a specific meaning in this context, meaning the “track to a fix”, i.e. a defined end point.
We have previously discussed the way that the magnetic heading is derived from knowledge of the current position and a look-up for the magnetic variation a that point, and is only then presented to the crew on the MCP as the last step.
@Richard
The use of term “one sigma” is highly misleading when referring to oscillator drift. “One sigma” is appropriate for characterizing the drift of an ensemble of such oscillators or the drift of a single oscillator when logging multiple trial runs.
In almost all observed examples of oscillator drift it is characterized by a one-sided movement, and is not subject to filtering or averaging as a Gaussian distributed error (implied by a one sigma characterization) would be.
I have no idea what you mean by “made it difficult for the official search to come to a conclusion”. Are you referring to humans i.e. SSWG.
It’s not all that clear that Indonesian radar was switched off after midnight that day. Medan military radar tracked MH370 flying to IGARI and must therefore have been in operation after midnight or until 0:21 local.
An Indonesian security spokesperson also said:
“Agus said, ‘another military radar suggestion said that it was once detected in the Andaman Islands. So, it could very likely have cleared Sumatra island in the north before making another turn to the south until it was 2,500 kilometers from Perth.’
‘Don’t be misled by graphical illustrations and maps because our earth is not flat like those maps,’ he added.
When asked about the possibility some of the military radars could have been inactive at the time MH370 flew over Indonesia, Agus said, ‘don’t trust rumors so easily.'”
http://www.thejakartapost.com/news/2014/03/26/govt-insists-mh370-did-not-fly-indonesian-airspace.html
If the main source of BFO error is deemed to be oscillator drift, shouldn’t an estimate of that error for MH370 be based exclusively on the historical performance of the equipment installed in 9M-MRO, and not be influenced by errors observed in flights of other airplanes?
@Nederland
Give it up. The Indonesians are faced with one of two horrible things to admit.
1> The radar was inactive.
2> The radar was active but did not see the aircraft.
There is little doubt, based on what we know, that MH370 did not fly in range of Indonesian radar.
“Don’t trust rumors so easily” is a blatant non sequitur.
@DennisW
I think Indonesia made it reasonably clear that they didn’t detect MH370 in their airspace (which casts some doubt on it having turned south before 18:40)
@Gysbreght
The drift of an oscillator can be modeled as integrated white noise. You really cannot determine future performance from measurements of past performance. Other oscillator errors such as aging and temperature coefficient can be sampled and accepted for.
@Brian: re: “anti-Perth”: I appreciate your efforts to salvage the ISAT data log’s credibility. But I’m forced by simple common sense to reject both your premise and your conclusion.
It is perfectly plausible to suppose that whoever falsified the data could have known all about “anti-Perth”. (Heck, it could even have been an Easter egg buried specifically to breathe the appearance of life into arguments such as you are attempting now, but I don’t need this to be true for the previous statement to hold.)
It is also perfectly plausible to suppose those without any knowledge of “anti-Perth” could still come up with a credible con job. If the values were calibrated to the actual ISAT logs of similar flights – each with the same error embedded – then they’d still manage to come up with credible values, by sheer mimicry.
Finally: under G or E, the 80-day delay in the publication of this data log remains unexplained; under C, this interminable delay is REQUIRED to sort out such niggling details as you postulate. (C also explains the otherwise coincidental March, 2014 ISAT Board appointment, but I digress.)
Brian, I don’t openly discuss C on a careless whim. Please know that I would be thrilled to be proven wrong – because it darkens my heart to see where the evidence is leading us.
I would like to add that the position accuracy enters the calculated error twice. Firstly in the frequency compensation calculated in the AES that determines the measured BFO, and secondly in the calculated BFO that determines the calculated error.
Since aircraft speed and position are determined by an inertal navigation system, and Schuler errors are inherent in all inertial navigation systems, it may be worth noticing that the error in Fig. 5.4 of the DSTG report exhibits a cyclic variation at approximately the Schuler frequency.
@Dennis @AuntBea
A reminder that this is what Victor had to say after reviewing de Changy’s material: (http://jeffwise.net/2016/08/12/did-mh370-plunge-or-ditch/comment-page-2/#comment-180011 )
“Regarding the simulator data found on the computer, it is true that many paths were found. However, the coordinates which we believe to (be) snapshots of a flight to the SIO were the only deleted coordinates found on the MK25 drive, other than two other coordinates of a plane parked at KLIA. This makes the coordinates much more significant that “one in a thousand.”
@Gysbreght
Nice catch. The variations (periodicity) are damn close. Close enough to pass the eyeball test. Somebody should look at the magnitudes to see if they make any sense.
@Matt
I believe the KL coordinates may well have been from the same flight before it took off.
@Dennis
The statement “this confidential analysis of captain Zaharie’s home flight simulator reveals evidence the captain tried to hide by wiping his hard drive.” starts at 5:38 in the video at
https://www.youtube.com/watch?v=ZQHl5SmA08A
The fourth sentence in
http://www.salon.com/2014/04/03/malaysia_airlines_flight_mh370_update_fbi_completes_examination_of_pilots_flight_simulator/
says “Data from the simulator had been wiped in February.”
If there is up to 40hz BFO errors, what kind of end points are there that could be landing sites?
@Dennis
Note that deleted and wiped are not the same thing.
Deleted means the file is removed from the directory and the space used is available for new use. However, the data is still there and can be recovered with the proper tools if the space has not been reused.
Wiped means the disk is rewritten with new data (often zeros), The old data is gone forever.
Hi Aunt Bea,
Yes, wiping and erasing are not the same which leads me to believe the terms were not used correctly. If the drives were wiped the data would not be recoverable. Right? I merely assumed, perhaps incorrectly, that the words selected were not selected with care. I still found no use of the term “main drive”.
My sense was both statements were referring to the six deleted points.
Gsybreght
My first pass look at Dr. Schuler showed that positional and heading errors were negligible. BFO (velocity error) error on the order of a Hz seemed possible (~1 ft/sec) for uncorrected errors.
@Brian Anderson,
You said: “The term TRK has a specific meaning in this context, meaning the “track to a fix”, i.e. a defined end point.”
There is no definition in the AFD manual that I could find of what the word “track” means in that document. There is no “fix” to track to in this case. It appears you are applying your own meaning, and thus you are guilty of what you accuse others. In your own words “. . . you are applying your own interpretation of the functionality.”
If you can show some documentation that an upcoming waypoint or end point is required to “set” the TRK HLD direction, then you would have a case to make, but there doesn’t seem to be any such requirement. If you can find it, then please show it.
Here’s another reason that an “end point”, as you call it, is not required. I guess you did not bother to read the AFD manual I referenced, because it says on page 10:
“Heading/Track Hold (HOLD) Switch
Push –
• selects heading hold (HDG HOLD) or
track hold (TRK HOLD) as the roll
mode
• displays HDG HOLD or TRK HOLD on the PFD roll flight mode
annunciator
• the AFDS commands wings level
and holds the heading or track
established when wings level is established.”
Note the third bullet. It says when the TRK/HDG HOLD switch is pushed, “the AFDS commands wings level and holds the heading or track established when wings level is established.” In other words, if the aircraft is banking when the TRK/HDG HOLD switch is pushed, the AFDS first stops the bank until wings are level and then holds the track or heading ESTABLISHED AT THAT VALUE. It has nothing to do with any previously established end points.
For heading hold the software is simple; just keep the nose pointed in the same direction, and you don’t worry where the aircraft goes.
For track hold I would guess the software designers had to make a choice. Are we going to calculate a rhumbline (probably not a great circle) using the saved bearing value and use roll mode to follow that projected track? Or could we just measure the earth-referenced velocity vector using ADIRU/GPS and maintain the bearing of the velocity vector? None of the documents I have read give any details on implementation. If I were doing it, I would use the first method, calculate a course, and correct for cross-track errors off that course. In this case there is a course calculated AFTER the track/heading is established, but it doesn’t need an end point in order to navigate along it. All you need to compute the cross-track error is the lat/lon of where you were initially (when the heading/track was held), a desired bearing from that initial point (the value being held), and current lat/lon. So you don’t need an end point either to establish or to maintain the track/heading, and no documentation says an end point is required. It seems clear cut to me.
@Richard Cole, “…they have excluded the tracks to the 7th arc that make up the least likely 5% when the possible statistical fluctuations in the data are considered…” Another way of looking at it, though the context to me suggests otherwise, ie the 95% is, “…to indicate how certain the plane debris was not in the area they have already combed.”
Your other points have led to a worthwhile and illuminating discussion.
@Richard @Brock McEwen, “So the areas we search we know 100 percent that if we run over an airplane we’ll know for sure.” Maybe they have realised that though that claim, on 1st October 2014, might have been in defence of contract.
The recent statement does seem to disavow the earlier though there could be a misquote or the context above is awry. (I must say that as written there is a 95% confidence/chance that they have missed the wreckage though I have 100% confidence that it just came out wrongly)
@Nederland
you said (pay attention Jeff graphic came from you):
“I think Indonesia made it reasonably clear that they didn’t detect MH370 in their airspace (which casts some doubt on it having turned south before 18:40)”
You might want to read the link below and then lets talk about what the Indonesians said.
http://tmex1.blogspot.com
@Wazir Roslan
On second sight that piece from Besut is probably also a piece from a rocket like that Thai piece.
I believe we can thrust not any of those pieces can be related to MH370.
Anyway they are all much to big to have allowed the plane to fly on the way it did according to the data.
With my suggestion I was thinking of smaller pieces that might have seperated during an event at IGARI or around 18:22 and made their way to the seabed.
Wondering what the BFO error are like for a flights from BOM to PER ? And how they compare from “FMT” to SIO supposidly fuel end point
@DennisW @Nederland
‘Agus said; another military radar suggestion said that it (MH370) was detected IN the Andaman islands’
So IMO he states with this the radar was not switched off. More important maybe is the statement it (he must mean MH370, what else?) was detected IN the Andaman islands.
This means the FMT must have been a lot further north west then at ~18:40.
With the other statement; ‘we did not detect MH370 in our airspace’ they only state this, not that they did not detected MH370.
And with that statement they probably don’t lie.
Till out of Butterworth radar range the plane did not enter Indonesion airspace. And if it (MH370) went past the Andaman islands it entered Chennai FIR Indian airspace.
An FMT in this airspace could have avoided further Indonesian radar detection and avoiding their airspace too going south.
@Dennisw
Just a caution to the max range circle of the Indonesian radar of your link http://tmex1.blogspot.de/
The plotted range basically is the max unambiguous range for that radar type and does not represent the range for that specific radar at that specific day for the altitudef MH370 was flying.
Military radars in peace time are not operated 24/7 and when in operation are not necessarily operated with max available power output. In peace time they are often used as training tools for the own air defence forces training controllers and fighter crews.
Some general info on radars
http://www.radartutorial.eu/druck/Book1.pdf
http://www.radartutorial.eu/druck/Book1.pdf
@DennisW
Like to add that these statements make sence with the graphic you show on your site.
Indonesion radar range is just reaching the Nicobar islands. If thy saw it (MH370) in the Andaman islands they must have seen it at the time it flew out of their radar range.
If the FMT occured a ~100nm further to the nort-west on the same heading it (MH370) would have avoided further detection when going south ( it would fly out of west-radar range according to your graphic).