[Editor’s note: One of the most intriguing clues in the MH370 mystery is the fact that the airplane’s satcom system logged back on to the Inmarsat network at 18:25. By understanding how such an event could take place, we can significantly narrow the range of possible narratives. In the interest of getting everyone on the same page in understanding this event, I’ve asked Mike Exner for permission to post the content of a detailed comment he recently provided. One piece of background: a lot of us have been referring to the satellite communications system aboard the aircraft as the “SDU,” but as Mike recently pointed out in another comment, it technically should be called the “AES.” — JW.]
Until we have more evidence to support the theory that the loss of AES communications was due to the loss of primary power to the AES, we must keep an open mind. Loss of power may be the most likely cause (simplest explanation), but the fact is we do not know why the sat link was down between 17:37 and 18:25. My reluctance to jump to the conclusion that it must have been due to the loss of primary AES power is based on decades of experience in the MSS (mobile satellite service) industry. It’s not just another opinion based on convenience to support a theory. Let me elaborate on a few possible alternative explanations.
The potential for loss of the pilot carrier, due to the orientation of the aircraft in relation to the satellite, was increased as soon as the airplane turned WNW. Between the time of this turn (circa 17:50) and the time of the FMT (final major turn circa 18:25-18:40), the aircraft was flying more or less toward the satellite where the antenna pattern was near a null. Don and I have both looked at the antenna pattern in some detail and concluded that the antenna pattern and coincidental direction of flight were unlikely to be so bad that the pilot carrier would be lost due to this geometry. Moreover, according to a MAS Press Conference on March 20, 2014, there should have been an ACARS message transmitted at 17:37, but none was received. ( bit.ly/QFbF6C ) At 17:37, the aircraft was still over Malaysia SW bound, so the HGA pattern would not have been an issue at that point. Taken together, loss of the pilot carrier due to antenna orientation appears to be a possible, but unlikely explanation for the outage.
Ionospheric scintillation has also been suggested as a possible explanation for the loss of service during this period, but there have been no reports of other aircraft in the vicinity suffering a loss of service, so this explanation is also unlikely. (Note: Ionospheric scintillation in the equatorial regions can be a big problem for VHF and UHF communications, but it does not affect communications in the L band as much.)
The MCS6000 AES, located in the back of the airplane, requires a continuous feed of INS data (position, speed, etc.) via an ARINC 429 link from the computers in the front of the plane. If the AES stopped receiving INS data for any reason, then it would not have been able to steer the HGA, or compute the required Doppler corrected transmitter frequency. Thus, it is very likely that the AES would be out of service if there was any loss of this 429 data link, or the information carried over the link. Given that there was no VHF voice communications after 17:19:24 and the Transponder Mode S data was lost after 17:21:13, it is certainly possible that the INS data flowing to the AES was disrupted due to a common failure in some piece of equipment in the E-Bay. This explanation for the loss of service cannot be dismissed as easily as the two previous theories.
However, there is one additional observation that tends to favor the loss of primary power theory over the loss of INS data theory (or the other two theories above). We note that when the AES logged on at 18:25:26, the BFO values for the first few minutes thereafter appear to have been drifting in a way that is more consistent with a restoration of primary power event than a restoration of INS data event. If the AES power had been on during the outage, the oven controlled reference oscillator would have maintained a stable frequency and there should not have been any significant BFO transients following the 18:25:26 logon.
In summary, there are multiple alternative explanations for the AES outage, but loss of primary power is the most likely explanation. Like so many other necessary assumptions, like the mode of navigation after the FMT, we have no choice. We must base the search on the most likely assumptions while maintaining an awareness that few of the assumptions have probabilities of .999.
Oleksandr,
You decide on a route IGARI to MEKAR, you decide on what available evidence it will be consistent with. It’s the track depicted in the Beijing Lido RADAR image and 18:22 at (MEKAR + 10nm on N571), or not.
To AES & “failure modes”: 9M-MRO’s AES comprised 9 separately powered + 6 passive LRUs. I don’t understand how I could speculate on a failure for you. To gainfully contribute you have some understanding of this yourself?
IGARI turn & progress to MEKAR: it’s my opinion that the depiction of a realistic turn on ‘fig 2’ would have quickly raised a chorus of, “WTF, really? If it wasn’t spotted in real-time, it took how many days to spot that on RADAR playback?”
A route IGARI to Penang Island & intercepting the path depicted by the RADAR targets doesn’t break the stopwatch.
:Don
Rough Estimate for Supporter from graphics:
-41.957054°, 79.664334°
Hi all. I have a question directed at Mike and Victor. I’ve asked it before but I don’t believe it was ever answered. Jeff – if I’m off topic, please let me know.
The question goes towards the BTOs. Not necessarily the validity, but the interpretation.
As I understand, signals are sent in a block of time in order to prevent collisions.
Next, I believe, but I’m not sure, that the BTO is the time between the block boundary and the actual receipt of the signal. My understanding is that it is not a true round-trip time, but it is equivalent.
Is that accurate?
If so, my real question is this:
What is the possibility that some of the BTOs are off by exactly one block size? In other words, what if the BTOs are truncated but otherwise real? This would have the effect of misleading the search.
In computer logs, in my experience, it is fairly common to encounter time stamps that are off by a time zone. Other mistakes are possible – for example using a Unix time instead of an Apple time will yield a date off by 30 years. Truncation is a relatively common problem in non-critical data because log data doesn’t always get the same level of QC that the core functionality gets.
It’s also easy enough for a human to make incorrect assumptions about logged values in an attempt to clean up the data. It’s akin to looking at the odometer of an old car and assuming it has 90k miles on it when it really has 190k.
So, I ask because if the block sizes are small enough, the data could be perfectly valid but misinterpreted.
JS:
All the BTO and BFO values are measured by Square Peg frequency agile Channel Units located at the Perth GES. All BTO values are complete round trip delay times (less a constant bias term subtracted in real-time for convenience of data logging). There is no possibility of packet collisions on the packets used to measure delay. The bias is easily calibrated using ground truth data at KL. Many have now demonstrated this, and all the results agree closely with ATSB and Inmarsat calculations (bias = ~ -495,679 usec). (See derivation of range distance and bias calibration here: https://www.dropbox.com/s/e2ij54k8voxdej8/Deriving%20Net%20L%20band%20Propagation%20Delay.pdf?dl=0
There are many questions about other aspects of the disappearance of MH370 that deserve vigorous, ongoing research. But the accuracy and interpretation of the BTO data is perhaps the only thing that is solid, factual and not worth revisiting anytime soon.
@Benaiahu: Thanks! And wow.
Still might be nothing (it’s smack dab on top of a fracture line, which raises the possibility of manganese nodule prospecting) – I have a message in to Mike Chillit asking for speed and bearing.
https://twitter.com/MikeChillit/status/562698945668083715
Speed: 3 – 4.2 kts (varied). Last bearing: SW. Appears to be settling in to a fracture zone.
May still be outrunning a storm, but seems unlikely to me.
To someone yesterday:
“If you sum it all up to date: Because of FPDA, AUS missed MH370 too. Why? (ignore); SING also must have MIL radar (silent); Indonesia must have seen/tracked (but say they didn’t); Malaysia just lied.”
SMH 3.19.14 Missing Malaysia Airlines plane: plea to US to release Pine Gap data
“Malaysia believes data from US spy satellites monitored in Australia could help find missing Malaysia Airlines flight MH370 but the information is being withheld.”
The Malaysian Insider 03.26.14
(Quoting retired BA pilot Eric Moody — from 03.24.14 Daily Mail By Richard Shears for MailOnline and Amanda Williams and Ted Thornhill and Chris Greenwood)
“What I will say is that some agency knows something more than what they are letting on and I have experience in this.
“It took 11 years to find out how Boeing was able to ring a ground engineer in Jakarta who got to us after about 15 to 20 minutes after landing.
“A phone call was made just when my engines started going wrong. It meant they knew what was going on as they were monitoring us on satellites.
“Satellite monitoring stations by Alice Springs [Read: Pine Gap] and Guam were following us as we found out from declassified files years later.”
Don,
Thanks.
With regard to IGARI->MEKAR section, I think you a bit misunderstood me. I don’t question data (yet). I question theories, and assumption within these theories, particularly AP as it stands. Reason: this affects flight mode after 19:41, as well as position at 19:41 arc. I have to remind that a single FMT between 19:25-19:40 has no grounds; it is an assumption within AP hypothesis. FMT could happen 30 minutes later – another AP trajectory would still fit BTO & BFO, with similar residuals.
Specifically, my concern was about a reason/motive/purpose to fly via Penang instead of via Langkawi, assuming that the radar data are correct and there was an interim purpose to get to MEKAR:
1. A straight path is shorter, which would be an advantage if a purpose was to get to the Indian Ocean.
2. A trajectory could also cross similar zig-zag border between Thailand and Malaysia.
3. Langkawi airport could also be used to mimic approach instead of Penang.
4. MH370 did not fly exactly over FIR boundary at the eastern approach to Malay Peninsula; it could be done more accurately if it was a purpose.
5. Same with regard to any commercial route.
6. It would enter Thai airspace for a short time, hardly sufficient for Thai military to understand what was going on and launch interceptors.
It happened that the report, link to which was provided earlier by Dennis, proposed exactly this path, via Langkawi. It turned to be erroneous (if radar data is not faked indeed), but it demonstrates a logical path if a one wished to get to the Indian Ocean. I came to the same conclusion independently.
So why did MH370 fly to Penang first? So far I can find only 2 explanations:
1. An original intent immediately after some event at ~17:22 was different, but something again happened at Penang (~18:00). Possibly this something was followed by powering up AES at 18:25.
2. There are some military installations in Thailand on the straight path IGARI->MEKAR, and the purpose was to stay away. This installation could be RTADS-III_Khok_Muan.
What else?
Nihonmama :
“It took 11 years to find out how Boeing was able to ring a ground engineer in Jakarta who got to us after about 15 to 20 minutes after landing.
A phone call was made just when my engines started going wrong. It meant they knew what was going on as they were monitoring us on satellites.”
I think this story has become distorted, misinterpreted and embellished, to the point that it is now an “old wife’s tale”.
There is nothing unusual or sinister about engine monitoring in this fashion, and it is not carried out by some nebulous, unknown satellites operated by some foreign agency. It is in fact a normal monitoring function, I think using ACARS to transport operational messages of this type.
A B777 captain friend commented to me that he has had, more than once, a call from operations before even taxiing out to line up, saying that “we didn’t like the way the engine started up that time. Please shut down and try again”. All perfectly normal operating procedures – – – as long as ACARS is operational.
@ALSM – I’m not necessarily suggesting the data is wrong, but I’m not sure it can be settled, either, or that there aren’t alternate interpretations of it.
I’d still have to disagree that the 17 ground truth datapoints correlate to the location well enough to use that calibration for the rest of the flight. However, that said, I’m not sure it would change anything – perhaps it’s off by a few km.
But let’s focus on packet collisions. In your response, you say there is no possibility of a packet collision. Can you explain how this works? We have shifting frequencies and delayed signals – how does the system account for this so that two signals don’t arrive simultaneously on the same frequency? How big are the separations in relation to the expected BFOs? Does the AES immediately respond to the satelite’s query, or does it wait for a specific time slot?
I’m shaking the tree here and not trying to go down a rabbit hole, but I’m curious to know if there is any way a signal’s time could be logged improperly. In the grand scheme of things, such an error would seem to be more probable than a spoof, but less probable than the BTO being good data. That middle probability seems worthy of some discussion.
@Flitzer_Flyer:
“There is nothing unusual or sinister about engine monitoring in this fashion”
Is that why I posted the article?
Don,
With regard to a possible mechanical failure, I am looking for an answer, whether mechanical failure of a wing/engine could cause a short circuit that knocked out AES and a number of other systems. Unfortunately I am not a specialist in the design of electrical systems of aircrafts (math and physics are my passion), thus I have to rely on the expertise of specialists in this fields. What I am looking specifically for, is analogy with ELAL_1862, Qantas_32, JAL_123:
en.wikipedia.org/wiki/El_Al_Flight_1862
en.wikipedia.org/wiki/Qantas_Flight_32
en.wikipedia.org/wiki/Japan_Airlines_Flight_123
An interesting feature about 1862 was that air crash investigators concluded that the aircraft could stay in the air at high airspeed, but the lift became insufficient at low speeds (<500 kph) making landing impossible. Could something similar be a reason for MH370 to turn westward at Penang when the crew discovered they were not be able to land safely in KLIA, or Penang?
Now recall that the right wing of MH370 was substantially damaged in Shanghai. Another JAL123?
The only missing piece in this theory is how wing/engine failure could knock out electronics.
@Oleksandr :
“So why did MH370 fly to Penang first? So far I can find only 2 explanations:”
3.) Cpt. Shah was born in Penang. Maybe he had some reasons to fly over his city where he lived in his early stages of his life until he moved to Shah Alam, Selangor in Kuala Lumpur ?
JS,
The only chance for packet collision is on the R channel from the AES to GES. If a collision occurs the GES fails to decode anything from either simultaneously transmitted burst, neither AES receives its due response so backs off for a randomised period & retries.
All AES R & T chl transmissions are sync’ed to receipt of the continuously transmitted P ch frames from the GES.
Datacomms protocols aren’t subject to interpretation: they are very rigid, tightly defined systems. The word protocol is a clue.
:Don
Oleksandr,
OK, I understand your premise now.
Still, it’s nigh-on impossible to speculate a chain of events as you suggest.
We do believe the aircraft is still flying an hour after some event that brought about the deviation. Exercising your line of thought, following a non-catastrophic (plane still flying) issue, would one not expect a communication. The aircraft has 5 separate means of voice comm: 3x VHF, 1x HF & SATCOM. The VHF radios are under his seat in the MEC with one antenna above his head & the other on the aircraft belly; the remaining systems rely on, at least, antennas aft of the wings.
Langkawi’s closed at night. A leg to Penang follows an established airway, straight to MEKAR doesn’t, if the intent is seeding confusion but not alarm then Penang’s good.
:Don
@LouVilla
Took the words right out of my mouth. I was exercising restraint, but it’s nice to know that others out there are, well, seeing associations and coincidences.
Cheers
Thanks GaurdedDon. I understand your emphasis on protocol, but I’d point out that error handling is built into every protocol, which necessarily means errors and collisions are expected.
So that leads me to a few more questions. Let’s say there is a collision, and the GES fails to decode the signal. The AES to GES signal is retried after a “random interval.”
What is the magnitude of those random intervals?
How does a retry affect the BTO in the log? It seems to me that one of three things takes place::
1. the logged BTO is increased by the retry interval, or
2. the BTO is somehow measured from the beginning of the frame, and is unaffected by retries, or
3. the BTO is reduced by the length of the retry interval.
Option 1 seems like it would yield unrealistically high BTOs. Option 3 would require storing the retry interval. Option 2 would log valid BTO values but would be potentially calculated from the wrong frame boundary.
Can you weigh in on this, or explain why one of my assumptions is off base?
Nihonmama,
“Is that why I posted the article?”
‘All I know is what I read in the papers’ seems like a reasonable retort.
The Daily Mail, the paper everyone turns to for fact & incisive reporting. What Moody found, declassified after some years, was US Air Force research on the effects of volcanic dust clouds on turbofan engines. Classified because the research used volcanic ash effects as the basis for nuclear detonation dust cloud models.
MH370, Pine Gap, Jay Carney? Yes, maybe, but SAT2014 was held in Washington DC during the week commencing 10th March. Attended by Inmarsat CEO, VP CorpComm & others. A few words over a cocktail are as likely as trawling hours of IQ recordings from I3-F1 at Pine Gap to gain some leverage. Perhaps more so.
LouVilla & Spencer
I mentioned the same thoughts month’s ago as well. Down the M-Straights for a final fly by, then on to oblivion…….
35% of the priority area now searched and not a speck of anything – on the top or the bottom – but don’t question those BTO’s. Or link to an article that someone doesn’t like or a cranky cruncher will put you out with a fire extinguisher.
Nihonmama – the thrust of the article was that someone knows something, and I’d agree. It should have dawned by now that MH370 tragics like us with all of our disparate views and backgrounds care a lot more about this plane than anyone except the families. How all the relevant govts can be so indifferent(on the surface?) about it is a puzzle unless they are not all in the dark?
Matty,
Doubtless somebody knows something. But just as the number crunchers’ travail has sought to define that priority area, we can also debate the priority somebodies we’d like to answer some questions.
There’s an extensive list of questions the Malaysians still owe answers to.
However, just for a moment, speculate that the number crunchers’ numbers are in the wrong place and some secretly observed better numbers exist in the files of those all seeing & all knowing. Might one expect that those secret numbers, if not presenting a risk to those who see all, would be given a path out to help those charged with solving our mystery?
Wouldn’t a MAS Airbus A330 with RR engines or a B777 with P&W or GE engines have been a so much clearer cut vehicle for the conspiratistas. Yet, we’ve got what we’ve got.
:Don
JS:
It is 100% certain that the BTO measurement system does not make any of the types of errors you speculate about. First, there are no collisions in any TDMA system, including the Inmarsat system. It is impossible, by definition. Second, an AES has no way to know if a packet it sent has errors unless the GES tells it there was an error, and a retry is required. Thus, there are never records in the log that were not the result of a valid round trip time delay measurement between the time of a CU transmitted MLS sync word and the reception of an MLS sync word in the error free reply received by the same CU. It is bullet proof. If it was not, then nothing in your modern digital communications world would work. People figured all this stuff out decades ago. (Yes, for the 3 600b/s login packets, a 4600 usec correction is required, but we know that is part of the system design, so even those 3 cases provide valid data.)
If you were a digital telecom system engineer, you would understand all this. Since you obviously are not, please take the word of those that do know what they talking about and drop this nonsense. You are coming across as a fool or worse. I welcome technical questions from everyone, including questions that don’t make any engineering sense. I’m happy to help educate. But no one on this thread appreciates seeing this important blog cluttered up with repeated questions that are clearly coming from non-experts who insist on challenging experts over and over and over regarding the laws of physics and standard engineering practice, just to get people to engage. It is rude and disrespectful of those trying to have a serious discussion. So please, give it a rest.
@Matty: …and the central 35% of the zone (I think) contains around 85% of the probability density. I’m trying to work with Mike Chillit to further refine the precision of his charts, to see whether we can sort out whether the “optimal” 35% has been searched.
As someone who DOES care – deeply – and who agrees with your conclusion – 100% – let me say I am very grateful to those who interpreted the numbers so expertly. Without their ability to turn the data into precise locations, our suspicions would have been slower to germinate, and less rooted in fact.
Matty, I’m guessing the “crunchers” are angrier than we are: in addition to caring themselves, their expertise seems to me to have been used by officials to help sell a lie. All their science has ever said was, “IF the data is valid, THEN the SIO theory is strong” – yet they now seem to be getting the blame for the data NOT being valid. Not fair.
@All: if you care about closure for NoK, you’re on my team. [High five.]
@ALSM – I accept that you have the expertise, and that is why I am asking for clarification. I don’t understand the hostility though. As Matty points out, we are 35% into the search with no results, so it’s becoming more and more likely that something got missed along the way. I’m not pushing any wild conspiracy theory here, just asking how this log would work. I’m asking how the time difference between Event A and Event B is calculated in a computer log, and specifically what Event A represents. With all due respect, that’s not laws of physics.
You say that there is no possibility of a collision, but Don says collisions are only possible on the R-channel. To a layperson, that is a contradiction worthy of further clarification.
My question remains – if a retry occurs because of a collision, how does the correct BTO get logged?
@JS, let it go. @airlandseaman has been generous with his time and expertise.
@GuardedDon
Maybe someone knows something, but maybe not. It seems unlikely that friendly nations would stand by and watch the Aussies spend upwards of A$60M conducting a search they knew to be in the wrong place.
Of course, the US spent 2 Trillion dollars invading Irag on the basis of information less credible than the Inmarsat BTO/BFO values.
@Brock “…and the central 35% of the zone (I think) contains around 85% of the probability density.”
Some assumption has to be made about the probability distribution around the 7th arc to make such a statement, you seem to be using a Gaussian-type peaked distribution. The ATSB report tables 1 and 2 discuss in detail how the search area widths were selected and some of the contributions listed (e.g. glide range) are definitely not Gaussian in distribution (the aircraft would land anywhere but on the 7th arc with any straight glide). Even a circular course such as a spiral glide still biases the crash site away from the 7th arc. The referenced BEA/ATSB study of loss of control accidents came up with a 20nm crash zone radius, but assuming a probability distribution inside that radius would take it too far.
The area has to be searched in total before any conclusion can be reached, the search isn’t being conducting 100 times to allow calculation of the probability function.
@DennisW I agree that concealing information that could assist in the search would be an incredibly unfriendly act. If one of the powers has done that for some ‘security’ reason then we will never hear about it since it would cause huge damage if revealed now. The search team have done well to avoid any deaths (or serious injuries as far as I am aware) in the air and sea search to date – it would have been easy for someone to be swept or knocked overboard. I guess the rigorous one month on/one off cycle and the rejection of any replenishment/crew transfer at sea is part of that safety plan. Never get out of the boat.
Richard Cole:
Your comments on the probability distribution are right on target (no pun intended). In fact, for a circular descent, the probablity density is highest at the maximum distances away from the arc, and lowest on the arc.
@Matty:
“don’t question those BTO’s. Or link to an article that someone doesn’t like or a cranky cruncher will put you out with a fire extinguisher.”
Or they will try. And, that (authoritarian) response speaks volumes.
@Brock:
“their expertise seems to me to have been used by officials to help sell a lie.”
I was wondering when someone would have the courage to say it out loud.
Setting aside for a moment the possibility of a spoof by the perpetrators (on the plane), has another spoof, in fact, been effectuated?
“The horror… the horror…”
~Kurtz APOCALYPSE NOW
@Richard Cole: the Excel model I posted to this forum – twice; each time begging for peer review (which airlandseaman graciously provided, at a high level) – shows clearly the double-peaked result to which ALSM refers, and whose (assumed) absence you lament.
The 85% number comes straight from this model.
I certainly can’t complain that folks haven’t actually digested this model, yet – there’s a lot of info out there, not all of it useful. Here it is again:
https://drive.google.com/file/d/0B-r3yuaF2p72NU9Ia0dsN3JkeGs/view?usp=sharing
I sent Jeff a more refined version a couple of weeks ago – please let me know if you’d like a copy of it.
@Brock:
How would the flight track of QZ8501 fit into your theoretical model?
It is important that we do not reject a particular theory just because it does not fit the consensus narrative.
It is equally important that we don’t blindly accept the possibility of a theory just because it does not fit the consensus narrative.
Too often I see people quickly jump from supporting one theory to another without any level of technical discrimination. I could give examples that I have seen just in the past week, but I don’t want to start debating these theories again. Some of these theories can be easily debunked by reading the documentation or by properly doing the math.
I ask, “What should those here that know better do in this situation? Let the falsehood spread or try to end it?” I ask these questions quite seriously.
I had a situation just this week on Twitter where I corrected an obvious error that a contributor had made. Before I had a chance to demonstrate the obvious math error, the falsehood had begun to spread. When I did provide factual documentation correcting the error, personal insults were leveled at me, including comments about my mother. Should I have not said anything and let the falsehood propagate?
There is a place for both technical and non-technical individuals to contribute to our thinking about the MH370 incident because the incident is multi-faceted. That is not a reason to reject the technical input from those that have the technical expertise to help filter the signal from the noise.
Don,
I admit that your question with regard to communication is Achilles heel of “mechanical failure” scenario. It is exactly a reason for my previous question.
Is there possibility (I am not talking about probability) for some event related to structural failure to knock out 3x VHF, 1x HF & SATCOM at the same time? Are they completely independent, including the source of power? How many communication tools are accessible from outside of the cockpit? What actions are needed to switch from one VHF to another one?
If I am not mistaken, occasionally garbled communication via VHF was observed prior take off in KLIA. I hope Jeff will not get red face if I mention the reported, but presumably false, communication 17:30 in connection with this. Interestingly, flight 1862 also experienced problems with VHF on the route from NY to Schiphol, though I can’t imagine what correlation could be:
“During the flight from New York to Schiphol, three issues were noted: fluctuations in the autopilot speed regulation, problems with a radio, and fluctuations in the voltage of the electrical generator on engine number three, the inboard engine on the right wing.”
[Wiki, El_Al_Flight_1862].
Well here is a technical question – If BTO’s are apparently sacrosanct, will anyone give a categorical assurance/guarantee that the BTO’s numbers are not corrupted somewhere?
@spencer :
“I was exercising restraint, but it’s nice to know that others out there are, well, seeing associations and coincidences.”
It is without a doubt the most probable theory that one of the two pilots highjacked MH370 for some reason when the disappear of MH370 was really an criminal act. To execute this highly sophisticated operation we must assume that one guy came up with skill and opportunity. To date, based on all available informations in this case both pilots were the only ones on board to be able to execute this kind of operation. Nobody else on board was able to fly an B777 airliner this way.
However,even when this theory is the most probale one, it´s just an theory without hard evidence. MH370 is an aviation mystery and it is likewise most problable that nobody else will ever find out the truth even when the ATSB might find the wreckage of MH370 some day.
Despite all the coincidences and facts that points out in the direction of Cpt. Shah and makes him to the prime suspect in this case the Cpt. is innocent until his guilty is proven.
We live not only in an speculation nation in this case where everyone of us is most likely caught maybe for decades, no, we also live in constitutional states were peoples are innocent until their guilty is proven. We should never forget this.
Matty: How many BTO numbers do you need to be assured that they are not corrupted?
The reported BTO numbers out to 17:21utc, when the aircraft was at or about IGARI, all fit very closely to the known aircraft locations, on the ground at KUL and on climb out, and the track towards IGARI.
LouVilla,
From psychological point of view your explanation makes sense, even despite the darkness. However, how would you explain AES boot up ~18:25, absence of calls upon restoration of satellite link, and unanswered call ~18:40?
When I read these discussions about probability, my thinking switches to Malay Shamans.
@Victor
The second sentence of your recent post does not parse as you intended, but I think everyone knows what you meant.
The Internet can be a cruel place indeed. In many cases the desire to be brief can cut in ways not intended, and often criticism is not well-received even by members of your own team, the IG. Alternate theories to the fixed AP mode were dismissed out of hand on Duncan’s blog, and people that expressed them were told to go elsewhere. I am sure Duncan was not trying to discourage alternative views, and that his intent was to keep people focussed on the anointed path. I accept that, but it is an example of the knife cutting in the opposite direction. You cannot have it both ways.
There is a popular Italian saying of unknown origin that goes back to the Renaissance – “Se non è vero, è ben trovato” (“Even if it is not true, it is well conceived”). So it is with the IG and ATSB AP assumptions.
@Flitzer – yes and no. The 17 BTOs do not correlate well with known distance, but this is likely because distance varies much over that time, while the BTOs are somewhat noisy. Some are high by 20-40us while others are low by that amount, despite minimal plane movement.
So they fit, yes, but the sample is too small and the variations to small to say with any confidence that the BTO is dependent on the distance. THAT conclusion comes from knowing how the values are logged, not from their statistical correlation.
@Oleksandr :
” However, how would you explain AES boot up ~18:25, absence of calls upon restoration of satellite link, and unanswered call ~18:40? ”
When i boot up an communication device after it was shut down, it´s logical to expect that i want to talk. In the case of MH370 nobody had talked to someone on the ground after 17:19 UTC via SATCOM.
That means in my opinion someone wanted to sent hourly signals only after the position of the airplane was out of radar coverage, maybe to give the investigators a chance to find this airplane after an long long journey of searching.
But why ?
Maybe to give the world an opportunity to recognize how incompetent the Malaysian government really is ? This search will be a long one. So, the entire world has the opportunity to watch closely to Malaysia for a long time.
Is the Malaysian government incompetent ? I think it is. In my country (I´m not an malaysian citizen), i don´t want leaders they lost an airplane with 239 people on board an this guys have no idea where this plane went after it flew over my country for 60 minutes without an transponder signal, without communication and without to be intercepted.
This is absolutly unacceptable.
Did the highjacker might thought the same way ? I´m sure, we will never know but it is thinkable.
JS,
Are you referring to these 17 BTO samples, originally taken by ATSB June, of which 5 or 6 fall into 1%-ile non-exceedance area according to ALSM’s comment 2014-12-23, 9:44AM, with the reference to a later study by ATSB (atsb.gov.au(slash)publications(slash)2014(slash)mh370-burst-timing-offset.aspx)?
Citation from ALSM’s post:
• 50% chance it is within ±3.0 km of the nominal 7th arc
• 95% chance it is within ±8.3 km of the nominal 7th arc
• 99% chance it is within ± 10.6 km of the nominal 7th arc
Well, it is still possible…
@gysbreght: if conditions were similar to the hypothesis (no fuel, no pilot intervention*) my model tests, then yes, good back-test suggestion – thanks. If a known path looks like an outlier against my distribution, I’d need to recalibrate.
(* I’m not TOUTING that scenario – just TESTING it, via Bayesian analysis.)
@Dennis: First, the IG is a loosely-formed group of technical folks that share information on an email list and have managed to reach consensus in some key areas that have been described in reports. There have been and will continue to be disagreements on many grounds. Duncan chose to moderate his blog in ways he felt were most productive. If it is any consolation, I was also reprimanded at times for exploring theories that were “alternative”. And do you think Duncan would have allowed Jeff’s spoofing theory to be discussed? So a non-AP navigation mode was one of many topics that was to some degree off limits. That was Duncan’s right. But who could deny the tremendous exchange of information that occurred at that site? I know that I learned a tremendous amount.
The specific example I gave was one where a new theory was based on incorrect math. I make a distinction between this kind of false theory and the kind of exchange you and I had about whether or not MH370 was likely on AP. I think we can agree (I hope) that there is a right and wrong way to convert between ECEF coordinates and LLA coordinates.
Yes, the internet can bring out the worst in people. Part of the problem is it allows a certain type to cowardly make comments he would never consider doing in a face-to-face meeting.
JS:
Au contraire, the BTOs do indeed correlate well with known aircraft locations out to 17:21utc. You have to recognise that the BTO values are rounded to 20uS.
Have you calculated the distances and plotted these yourself? Which particular numbers are you debating.
Furthermore, BTOs after 17:21 fit with the radar tracks in the Malacca Strait, fit with 2 or more independent calculations of aircraft speed, and fit with 2 or more independent calculations of the fuel endurance range.
@Victor
Yes.
I was curious to see what it would look like to combine all of the following pieces of information together in one place:
ATSB Flightpath
Lido Radar
Early FMT (Ulich)
Late FMT (v13.1)
FIRs
Waypoints
Air Routes
First 2 Ping Arcs
Radar Ranges (Don, DS)
FR24 traffic sample
and Timestamps (UTC)
So, I created a composite diagram which shows all of it. Here is a link in case anyone else is curious:
https://www.dropbox.com/s/yvqf0lkbfsdwyjs/mh370-composite.pdf?dl=0
Very interesting to see how relationships between events begin to emerge when mapped out in space-time.
Orion,
Something similar has been in my Google Earth library for a long time.
It certainly gets very busy.
I’m interested in your depiction of a cone from a point annotated as ”T2(Don,DS)”. Could you explain what that is intended to illustrate?
:Don
@Flitzer – I did a regression on them. The correlation is very weak.
As I’m sure you’re aware, a regression is intended to obtain a formula, such as Y=aX+b, where Y=BTO, X=known distance, and a and b are constants that we wish to determine. If there was a correlation, the resulting formula would work very well among the first 17 individually. Randomly omitting some of those 17 would not change the formula, if there was good correlation. There isn’t. This is an objective statement – there is only one best fit formula for these values, and you and I should get the same results.
Bear in mind that I’m not suggesting the BTOs don’t fit the radar path or any projected path. I am only saying that the numbers themselves do not show a statistically significant correlation. Your reliance on them to show distance post-17:21 must be supported by a non-statistical source, such as knowledge of what the values represent. The BTOs are an accurate predictor of distance because we accept that they are accurately recorded and they are what we’re told they are, but NOT because they show a correlation standing alone.
Also bear in mind that the sample size and the amount of variation in the known distance values is too small to make any statistical conclusions.
The analogy here would be trying to calibrate a speedometer using a radar gun but doing only one speed. You might get a correlation but you can’t determine whether the speedometer scale is accurate without a broader range of speeds. This is why at one point many of us were keen on getting BTOs from an earlier flight. Even a single BTO entry from a materially different distance would be helpful.
Does that make sense?
Oleksandr
I’m sorry, I can’t help you with that line of thought.
:Don