If you were leading a high-profile international aircraft investigation, in command of the world’s most qualified technical experts and in possession of all the relevant data, would you bother listening to a rag-tag band of internet commenters, few of whom actually work in the space or aviation industry, and none of whom have access to all the data?
Most likely, you’d say: certainly not! But as time goes by, and the puzzle remains curiously impenetrable, you might find it worthwhile to pay a listen to what the amateurs were saying. You might even abandon some of your own conclusions and adopt theirs instead.
This appears to be the case in the search for Malaysia Airlines Flight 370, which disappeared en route from Kuala Lumpur to Beijing back in March. From the beginning, the authorities running the investigation — first, Malaysia’s Ministry of Transport, and later the Australian Transportation Safety Board (ATSB) — held their cards close to the chest, releasing very little information about the missing plane and maintaining a posture of absolute conviction. The investigators’ self-confidence reached its apex in April, when their methodology led them to an area of ocean where underwater accoustic signals seemed to be coming from pingers attached to the plane’s black boxes. Officials assured the press that the plane would be found in “days, if not hours.” But then it wasn’t. A scan of the seabed found nothing; the pingers were a red herring (perhaps literally!). Back to square one.
Meanwhile, on the internet, a group of amateur enthusiasts had come together from all around the world to trade ideas and information about the missing flight. The group, which came to call itself the Independent Group (IG), emerged from various online comment threads and eventually grew to about a dozen individuals. This was a truly spontaneous, self-assembling crowd: there was no vetting of credentials, no heirarchy of any kind. (Full disclosure: I count myself among this group.) Basically, if you seemed to know what you were talking about and could comport yourself in a collegial fashion, you were accepted into the crowd.
While the mainstream press was reporting the ATSB’s pronouncements as received wisdom, the IG was raising red flags. IG members were among the most vocal critics of the ATSB’s contention that the accoustic pings probably came from black-box pingers. And later, after a public outcry led Inmarsat to release a trove of data received from the aircraft, and the ATSB issued a report explaining how it had come to identify its current search ear, the IG dove into the new information with abandon, quickly identifying holes in the data and weaknesses in the official approach. In a pair of papers, the group recommended its own search area, hundreds of miles to the southwest of the ATSB’s officially designated zone.
Today, the ATSB has released an update to its earlier report, explaining why it has decided to reassess its conclusions and move its search zone to a new area — one that overlaps, as it turns out, with the IG’s recommended area. (In the graphic above, the white bracket shows the ATSB area; I’ve added a yellow dot to show the IG area.) Needless to say, this has caused elation within the ranks of the IG, who see the move as vindication of their methods, and indeed validation of their combined efforts over the last few months.
A few observations on the new report:
— One of the reasons the ATSB gives for the shifting of the search area is the recognition that Inmarsat data related to an unsuccessful ground-to-air telephone call attempted at 18:40 indicated that the plane had already turned south at that time. The IG had been basing its analyses on this data point for months.
— Since the June report, the ATSB has improved its BFO model by taking into account various factors — such as temperature shifts caused by the Inmarsat satellite passing through the Earth’s shadow and the mis-location of the Perth ground station in an important Inmarsat algorithm — that IG member Mike Exner has been working through in detail for months.
— The ATSB has fundamentally changed its approach in how it is assessing the plane’s likely path. In its June report, the focus was on what I call the “agnostic” approach: it generated a large number of flight paths based on as few initial assumptions as possible, then graded them based on how well they fit the timing and frequency data received by Inmarsat. This resulted in a population of potential flight paths that fit the data well, but did not make any sense in terms of how a plane might be flown. Some of the routes, for instance, involved multiple changes in heading and airspeed. Today’s report explicitly excludes such flight paths. The ATSB and the IG alike now assume that the last several hours of the flight were conducted without any human input — the crew were presumed to be incapacitated by hypoxia or other causes, so the plane flew on autopilot until it ran out of fuel and crashed. This has been the IG’s starting point for ages, and the fact that the ATSB has now adopted it is a major reason for why the two group’s search areas have now converged.
— You can see in the graphic above how an emphasis on matching the Inmarsat data will tend to lead you in one area (“Data error optimisation”) while an emphasis on routes that comport with real-world autopilot functioning will lead you to another (“Constrained autopilot dynamics”). To be sure, they overlap, but the peak area of one is far from the peak area of another. I think it’s important to realize this, because it helps us to understand why it has been so hard to get a handle on where MH370 went, why the official search area keeps moving, and why knowledgeable people have been furiously debating possible flight paths for months: the BFO and BTO data just do not match up that well. In order to arrive at its recommended area, the IG has been willing to accept much wider deviations from Inmarsat data points than the ATSB has been comfortable with.
— Finally, it’s worth nothing that the ATSB approach is superior to the IG’s in one important regard: it is at heart statistical, looking at families of potential routes rather than proposing and assessing one at a time. There is a tendency, as an individual–and I have fallen into this myself–to cook up a solution, run an analysis, and to be so impressed with the result that one wants to shout about it from the rooftops. (Ask me about RUNUT some time.) The IG has come up with a search area essentially by pooling together a bunch of individual solutions, each of which is generated by a different set of procedures and different set of assumptions. It’s a herd of cats. To really move the ball forward a more rigorous approach is needed, one that takes each procedure and sees how it would play out if the assumptions are methodically modified.
The upshot is that, since the early days of the investigation, the attitude of search officials has changed radically. Once dismissive of amateurs’ efforts to understand the incident, they have clearly begun to listen to the IG and to turn to it for insight and ideas. Indeed, you could say that since the release of Inmarsat data and the issuance of the ATSB report in June, the search for MH370 has become effectively crowdsourced: a de facto collaboration between the professionals and a spontaneous assemblage of knowledgeable experts.
UPDATE:
The overlap between the ATSB’s analysis and the IG’s is more evident in the image below, courtesy of Don Thompson. It shows the fan of values calculated by ATSB to match likely autopilot settings.
@Gysbreght
>> The B777 flight envelope protections do
>> not disengage, but manifest themselves by
>> demanding an increasing stickforce to
>> override them.
That is what is known as a “distinction without a difference.”
The difference is that the pilot must maintain a high pushforce as long as the speed is above VMO/MMO.
@Geysbreght
>> The difference is that the pilot must
>> maintain a high pushforce as long as the
>> speed is above VMO/MMO.
Unless we assume the pilot was an invalid, that is obviously irrelevant.
@D Hatfield,
The maximum true airspeed of 589 mph occurs when 330 kIAS equals M.87, i.e. at a pressure altitude of 30477 ft.
@Luigi Warren,
it obviously depends on what you consider irrelevant. Do you know the stickforce required and how long it is maintained?
@Gysbreght
>> Do you know the stickforce required and how long it is maintained?
No, and I don’t care, because I do know this functionality would not be provided if you had to be Arnold Schwarzenegger to use it.
Has it occurred to you that the “excessive force” mentioned in your reference is designed to be a deterrent, to prevent the pilot from exceeding limit speeds inadvertently and for prolonged periods?
@Geysbreght
Yes, I assumed that was the point. And, it was a somewhat controversial design choice because it’s only a deterrent, unlike on the Airbus. If someone were to, say, steal the plane, they can gun it to the limit on a 777. Which is where we came into this discussion…
@Luigi Warren,
The discussion was about your reply: “That is what is known as a “distinction without a difference.””
I would hope that the difference is now obvious.
Some have asked for, or speculated on the timing of the RAT deployment, APU auto start and second engine flame out times. The info to figure this out is in the June 26th Report and October 8th update. It takes about 02:40 minutes for the AES to attempt an automatic login request after power is applied. It takes about 01:00 min for the power to be restored after loss of power from the second engine driven generators. The AES is powered up immediately after the power is restored. So, backing up from 00:19:29, the second engine flamed out at~00:15:50, power was on at 00:16:50, and the login was at 00:19:29. The first engine probably flamed out 5-15 minutes before the first, depending on the engine PDAs and fuel balance at the start.
The October 8th update contains a good estimate of the fuel limits and so called aircraft performance limits. They are close to the IG estimates for the southern boundary on the 7th arc. Boeing has more data (PDAs) than the IG does, so folks should trust the ATSB southern boundary estimate for now. I don’t think it is coincidental that the ATSB’s updated prediction and the Sept 26th IG prediction are close to the intersection of the southern performance limit and the 7th arc. These are mostly independent estimates, providing some added confidence that the assumptions in these two path model (autopilot mode, etc.) are probably correct.
@Gysbreght
A “distinction without a difference” is hairsplitting for rhetorical purposes when the distinction does not change the key point under discussion. As is the case here.
Now, I suggest the BFO tweakers go back to their models, calculate appropriate adjustments to their fuel limit assumptions, and adjust their preferred search areas accordingly.
@Bobby: Here is the basis of my fuel analysis for your path. If you want a more detailed write-up, you will have to wait as I am a bit busy.
Using the Boeing Flight Planning and Performance Manual (FPPM) for Long Range Cruise (LRC) at 35,000 rpm (for GE engines), I fit the curves for speed and fuel consumption as a function of plane weight. Since we know the zero fuel weight (ZFW) and fuel weight at 17:07, I can use the fits to numerically integrate forward in time until fuel exhaustion.
Doing this with a fuel weight of 43,800 kg at 17:07 leads to fuel exhaustion at 00:42 and a distance of 3,563 nm. But that range assumes the plane is always flying at the LRC condition, which varies between Ma=0.83 to Ma=0.77 over the range of weights.
For your path, the air distance is 3591 nm, or about 28 nm greater than the range flying at LRC speeds. But there are reasons why it is unlikely you would even reach the LRC range:
1. Your air speed is around 500 knots, which is Ma=0.85 with a 10K temperature offset, and Ma=0.86 at a 5K offset.(I calculate an average air speed of 502 knots, while you cite 499 knots.) On the other hand, the LRC range is between Ma=0.83 and Ma=0.77.This higher Ma will certainly shorten the range. Let’s say it is a 2% reduction.
2. The Performance Degradation Allowance (PDA) of the engines will reduce this range further. You cite a 3% number. Let’s assume it is 2%.
3. The air temperature was about 10K higher than the standard atmosphere over much of the flight, which will further reduce the range by a couple of percent. A source told me to allow 3% per 10K offset of static temperature. Let’s say it is 2%.
Adding up all these effects (about 6%) reduces the achievable range to 3349 nm, or about 242 nm short of what is required for your path. For this reason, I question whether your path can be reached with the available fuel.
@airlandseaman,
As I read the ATSB june 26th report, and the october 8th update, they give about equal weight to the “constrained autopilot dynamics” method and the “data error optimisation” method. Since there is no evidence that the airplane was under autopilot control, or at which time there was a cessation of human inputs, I believe the ATSB assessment is appropriate.
I am somewhat puzzled by the repeated reference to “engine PDAs”. As I understand it, PDA stands for Performance Degradation Allowance. I believe it is used for flight planning purposes, to calculate the fuel required for a flight to be undertaken. If that is correct, then it is obtained be monitoring the fuel consumption of an individual airplane against a standard ‘book performance’ for the airplane/engine model. It combines the degradation attributable to the two engines installed on that individual airframe, and any aerodynamic degradation attributable to the airframe itself. It is more difficult to separate the contributions of the individual engines.
Even if the fuel consumption of each engine is known, it is doubtful that it would permit a calculation of the fuel tank imbalance at fuel exhaustion. Since fuel asymmetry requires trimming of lateral/directional controls, it is detrimental to performance and minimum control speeds. Therefore most airplanes utilise a fuel cross-feed system that automatically transfers fuel between tanks when the asymmetry exceeds a certain tolerance.
The ATSB june 26th report states that the modelling to determine the aircraft performance limits did not include individual engine efficiency. That is appropriate since degradation would reduce the estimated range capability of the airplane.
@Victor,
Incompletely described and undocumented (i.e., “a source told me . . .”) calculations cannot be duplicated or verified.
The ESAD range you quote also rules out the IG route as being reachable.
Nipping off the left a/c bus effectively removes the barrier of stick protection.
Furthermore (and most obviously), it appears that this is precisely what took place from 17:19(21)-18:25. It answers ALL unknowns, quite simply.
Luigi, LaurenH:
Luigi:
“So, what is the probability that the co-pilot’s cellphone reconnected at 35000 ft in the 16-minute hop from Kota Bharu to Penang?”
Well, based on the NYT piece, it would certainly appear that a cell connection at FL35 is possible, doesn’t it?
The question I’m more interested in, quite frankly, is what was happening on board at the time the call was made — and if it was 1st Officer Hamid who made the call, WHERE was he on the aircraft when he made it?
I found it very interesting that the 04.12 NST article http://t.co/Xb8m1gH6Vi, which was later denied by Hishammudin Hussein (but confirmed by CNN’s story on 04.14), characterized the call as “desperate”.
Why did NST decide to go with that descriptor? Is it mere journalistic hype designed to capture eyeballs? Or is the content of the call from 1st officer Hamid’s phone ALSO known?
Further, if NST has it right, was this ‘desperate’ call made from the cockpit — or from the main cabin (or even a bathroom) — where Hamid might have been if he were locked out? If so, that would certainly suggest that he wasn’t one of the perpetrators. Or, if he was, maybe that ‘desperate’ call was goodbye?
And let me just ask another (elephant) question that I’ve posed elsewhere but never gotten a response to: who, if anyone, was riding JUMPSEAT on MH370?
LaurenH:
“Nihonmama – The Delta manual shows ceiling values of 42,000ft and 43,100ft for a B777-200ER with Rolls Royce engines. I did not immediately see an explanation for that difference. However, I found posts in PPRuNE saying the ceiling is limited be the total weight. This means that just because the a/c can fly at FL420 does not automatically mean it can reach that altitude when heavily loaded.”
Thanks and yes, I certainly get that. If I’m not mistaken (please correct if so), MH370 was carrying just over ⅓ of its max fuel capacity (which would be block, plus filed alternate destination (on manifest), plus ICAO reserves). It was also not carrying its maximum number of passengers. So while certainly ‘loaded’, it’s takeoff weight of 223,200 kg was well shy of it’s maximum — 297,550 kg.
Referring back to an earlier comment in this thread:
Nihonmama
Posted October 14, 2014 at 1:18 PM
“Let me also say that even though the *certified* max altitude for a 777 is 43,1000, when I asked my cousin (in March) about the reported climb to 45,000 (later dismissed), he did not push back and say that altitude was beyond the capability of the airplane. But he did that if someone wanted to take out everyone it the main cabin in seconds, a brief climb to 45K altitude would do it.”
I had no manual with me during the conversation referenced above. But the cousin I spoke with is not only a captain with many hours in the 777, he was a member of the pilot team Boeing consulted with when they designed that airplane. Please take from my record of our conversation what you will.
I’ll comment further about the ‘altitude’ story in a post to follow.
@airlandseaman: thanks for your comments re: performance analysis.
If the ATSB’s (Boeing-fed) fuel model is our best estimator of the southern 7th arc crossing (fastest speed MH370 could have flown, and still stayed aloft until 00:19 UTC), isn’t it then also our best estimator of the NORTHERN 7th arc intersection (SLOWEST speed it could have flown, and stayed aloft until 00:19 UTC)?
If so, are you now prepared to concede that the “decompression scenario” is not fuel-feasible (too slow)?
(I’m not trying to cause embarrassment, nor flog a dead horse, Mike. It truly pains me to have to criticize any aspect of the IG’s outstanding efforts as outside (and fellow) auditors of the ATSB. Unfortunately, your decompression scenario – however unwittingly – happens to offer a fig leaf to the ATSB’s April/May best estimate path (exact same speed, to exact same terminus). As a fellow relentless pursuer of the truth, I’m sure you agree the time has come to audit their decision to search at the end of an infeasible path.)
Thanks,
Brock
@LaurenH:
Sorry – forgot to add that during the aforementioned conversation, I didn’t get into the specifics of MH370’s weight (it wasn’t known at that point) and what bearing that would have on a potential climb to 45K.
I intend to circle back to him to inquire on this point.
@LG – based on Mike Exner’s comments, my understanding about the antenna steering is that it is solid state, not a physically steered antenna. I don’t fully grasp this concept, but I’m going to take a stab and let others correct it as needed:
My guess is that the antenna consists of multiple antennas, and the signal is sent from different ones at infinitesimally different times. The offset is based on the speed of light and antenna distance. As a result, the signal from the antennas overlaps neatly in one direction but cancels out in other directions due to the interference pattern between the waves.
Mike? Am I close here?
If it is indeed solid state, it could be steered instantly, but there may still be a lag between position updates coming from the FMS. Going out on a limb again, there may also be smoothing or prediction going on so that a signal isn’t screwed up in a turn.
But, it may simply be that the antenna is always up-to-date.
Hopefully somebody can quantify this lag, if there is one.
One other question, relating to radar: does a 777 (and its crew) know that it is being pinged by radar if the transponder is off? Is there any indication to pilots that they are within any radar coverage?
@JS
>> One other question, relating to radar: does a 777 (and its crew) know that it is
>> being pinged by radar if the transponder is off? Is there any indication to pilots
>> that they are within any radar coverage?
Interesting question, especially since the last military radar contact was at 18:22 and just 3 minutes after that the pilot rebooted the satcom. Another 3 minutes later, at 18:28, a signal with a highly positive, still-unexplained BFO spike — consistent with the onset of a rapid climb — was transmitted to the satellite.
A corollary question would be, what limits the range of military radar? Is it based simply on the curvature of the earth? If so, that might have been easy enough to map out out beforehand, based on flight altitude and the position of the radar installations.
@Luigi – yes, I agree, to the extent the mil radar is known, it could be avoided. However, along those lines, 3 minutes seems to be a little short, unless the range is known to sharply drop off at the same place every day. I doubt that part, but it’s certainly possible.
I also doubt that the plane can “hear” the radar (other than possibly through the transponder, when it’s on).
But, if it could, then a pilot could be reasonably assured that he had left the range. In that position, he would know exactly how the range was degrading under the conditions THAT NIGHT, and he could avoid it.
@JS
Another possibility, inspired by Rand’s suggestion of last week, is that there was a communication on a line-of-site path with similar range limits to the radar — e.g., direct radio comms on a military channel. Then, the satcom reboot could have been to keep open a “last chance” comms option after those talks broke down. I’m inclined to think the reboot was for that general purpose regardless of whether these was any prior communication, but it’s conceivable that radar range is here just a proxy for radio contact.
JS
The Ball AirLink antenna system consists of a left and right side phased array, plus a control system. Each array has about 16 patch elements arranged in a grid. Each patch is feed through a beam forming network such that a microprocessor can control the relative phase of the signal arriving at each patch. By feeding the patches with different phases, the beam is steered electronically (instantly). The IRS data used by the AES for Doppler compensation and HGA steering is continuously updated.
http://www.ballaerospace.com/file/media/D1811_AIRLINK%20HGA%20ds_0114.pdf
http://www.spectrumsignal.com/publications/beamform_primer.pdf
@Bobby: I gave you all the information so you could repeat my calculation. You have the LRC tables. You can perform the integration as I did. There is no mystery.
I will transmit to you by email the spreadsheet for the curve fits and the integration.
Relative to the fuel flow increase with static temperature, the 3% per 10K number I quoted is from aqqa. (I will let him identify himself if he chooses.) I know that he will be soon sending you a more complete description of his fuel flow model. He has followed two approaches: integration of the LRC relationship as I have done and also a calculation based on the Ma=0.84 cruise condition.
JS:
I answered the questions about the HGA, but the message has not posted. It had two http links, so maybe it will show up later.
@Spencer
>> Nipping off the left a/c bus effectively removes the barrier of stick protection.
Interesting. I don’t really see what the problem is, anyway. I doubt that this feature has been implemented to support only sudden maneuvers. The 777 has been consciously designed to allow the pilot to override the prescribed flight envelope. Evidently, there is debate as to whether the risk of allowing a pilot to do that outweighs the risk of dangerously constraining the pilot’s options in an emergency. The Airbus designers chose one philosophy, those at Boeing another. Now, if a plane were to experience an explosion/fire/decompression in (say) the middle of the South China Sea, they might be very much in a hurry to get it back home, before fire consumed the plane, and to keep it at well below cruise altitude at the same time, to avoid returning with a cargo of dead passengers. That seems like precisely the sort of situation where the ability to fly outside the normal, prescribed envelope would be useful. Certainly, one would not want to be flying at half speed to avoid bird strikes or save fuel in this situation. I think Boeing would be somewhat embarrassed if one of their airplanes were to be consumed by flames or all its passengers asphyxiated simply because they made the override stick pressure too fatiguing to apply for the odd twenty minutes.
Of course, anybody who commandeered a plane for some nefarious purpose would also probably be in a great hurry to get where they’re going, and therefore more than happy to take advantage of the same functionality.
@Luigi
On the whole, I agree. However, it is my understanding that a positive correlation exists between the degree in which the flight envelope is exceeded and the requisite stick force needed to attain/maintain ‘desired’ excess. Thus, for Zaharie, the absence of this impediment would have allowed a virtually unprecedented exploration of flight envelope (not a whole hell of a lot on the line, after all). I shudder to think of what some (see below) of those passengers perhaps experienced.
A ‘zoom’ maneuver, so I’ve been told by a t7 pilot, could achieve FL450. This is not some fictional figment of the imagination. The weight was not duly prohibitive.
The idea that the a/c maintained FL350 from Igari onwards (for myriad reasons, some of which Luigi has correctly illuminated) defies a sensible narrative if one is to believe in a deliberate (nefarious) diversion. Which i think is incontrovertible, IMHO.
Brock,
<a href="https://www.metabunk.org/threads/mh370-preliminary-report-released-full-text-and-files.3580/page-4#post-107415"
This post (written by a poster whose writing style closely resembles yours) show a table of fuel flows per engine at LRC conditions and under holding conditions at various elevations. This table shows that e.g. LRC fuel flow at 35000 and 200,000Kg total weight is 3085 Kg/hr per engine. The corresponding TAS is about 475 knots. At the same weight, the plane can be flown at any elevation down to 1500 feet with lower consumption of fuel per hour, and with TAS as low as 207 knots. I think you are the one beating a dead horse.
BTW, there is at least one other source of similar data for a 200ER with Trent 892 engines, but I don't want to run afoul of link restrictions.
@Spencer
Incidentally, I was not seriously proposing that the diversion was due to an accident. The ship sailed on that explanation long ago.
I am reasonably convinced that the plane did go to low altitudes for a portion of this flight. I think the 35K thing is just laziness on the part of the tweakers — too many free parameters to model, too much evidence to weigh and integrate, too much storyline to agree on. Whether the early reports about an immediate climb are true, I have no idea. I don’t see anything to corroborate it, but I wouldn’t dismiss it either. The most important details of this story came out early and were buried and blurred for a long time because the man at the podium didn’t give them his “official” seal of approval. That was by design, of course.
@Luigi
I know you’re not in any ‘accident’ camp. I, too, was directing my FL350 comment to the tweakers on this forum, though it will invariably fall on deaf ears.
I find it strange that the FL450 report would have simply materialized out of the ether, erroneous and unfounded. Put another way, it did not. It originated from somewhere and was most likely neither disinformation nor without substance.
Ironically, this calls into question the very scenario I am wedded to…unless Z was not really interested in negotiating in earnest, and was communicating something much more harrowing to H (I have some thoughts on this).
In many respects, a depressurization would have been necessary to achieve his presumed goals, A cabin full of live souls cruising fast and low over the mainland would not be desirous, one would think.
Anyways, off to bed. I enjoy reading your thoughts and largely agree with your general assessment of what transpired…the real mystery is the ongoing Malaysian hijinks, and H’s complicity. Time is not on his side, I dare say.
@Luigi
Could you elaborate on what you are referring to?
>>>>”The most important details of this story came out early and were buried and blurred for a long time because the man at the podium didn’t give them his “official” seal of approval. That was by design, of course.”
JS – On radar, interesting one. Military planes know they are being targeted because they can detect enemy radar as it comes onto them and it’s all old stuff. AS soon as that SAM crew switch on the radar an alarm goes off – read up some of the hair raising episodes Blackbird crews had over Libya! If a 777 did not have that capability ordinarily could you configure one with the know how?
Luigi – if a pilot has indication he has left radar cover then a further 3 mins nails it. You have disappeared, and I think all such radar is limited by curvature and cover is tied to altitude unless it’s a Jindalee kind of setup. And these pilots know the layout pretty well either way I would think? But why delay that turn and then head through Indon space? Confusing aspects from every angle.
Matty: Regarding the possibility of jury-rigging a facility for radar detection aboard a 777: I can recall reading many years ago of a dogfight training simulation at a Nevada training base where they deployed F-5s with off-the-shelf, broad-specturm car radar detectors, putting them up against whatever interceptor flavor of the day. The F-5s did reasonably well with the simple gear, if memory serves.
I find it interesting (!) that the issue of Indonesian radar data was never really pursued by the Malaysians, and that they rather simply accepted (and continue to accept) that Indo did not detect MH370. Perhaps we can attribute the lack of any Indo radar data/information to someone being asleep at the switch in Sumatra, but what remains is the apparent lack of any pursuit of this data/information on the part of the Malaysians. If such data/information has been made available to the Malaysians, the only remaining quesiton is why, then, has it not been made public? I would think that any rationale grounded in miltary heirarchy and secrecy would have been overcome by the very real need for more ‘visibilty’ regarding the period/location of the aircraft’s transition to a flight trajectory taking the aircraft south. And with a new, populist, non-military executive now heading up Indonesia, one would think that there would be a new opportunity for an appeal by Malaysia for the release of such data/information. What we have, rather, is only relative silence, while Hishammuddin continues to accept condolences for the stress that he suffers. When I even so much as misplace my sunglasses, I diligently and doggedly look for them until they are found, rather than ask my Australian and Chinese friends to try and find them. There’s a tell-tale dropout in his behavior, as far as I can discern.
@spencer
I also wonder about the source of the FL450 reports, whether or not there was any substance to them. As I understand it, the plane was not on primary radar at the time of the diversion. Even if it had been, my impression is that radar could not have provided that information. BFOs could have revealed it, but the satcom was turned off comcomitant with the diversion, and there is no data in the released log up until the pilot rebooted the satcom three minutes after retreating beyond Malaysian military radar coverage.
If the FL450 climb occurred, it might simply have been a tactic to immediately quell the passengers and locked-out crew, unrelated to cabin pressure. If I was sitting in the cabin and that happened, I think I’d get the message pretty quickly: the guy up front is in control, nothing to do but sit tight and hope for the best. It such an obvious first move, I’d almost be more surprised to learn it didn’t happen.
@D Hatfield
>> But why delay that turn and then head through Indon space?
>> Confusing aspects from every angle.
I look at this incident pretty much as if I was trying to interpret an unheard argument and ensuing apparent altercation between two strangers viewed across a public square. Looks like they went eyeball-to-eyeball, then there was a retreat with the residual potential for a cooling-off, truce or renewed confrontation, before the challenger finally stalked off in a huff, never to return.
@D Hatfield
>> Could you elaborate on what you are referring to?
The most important information we have relevant to the nature of the incident (*not* as to the exact location of the wreckage) is the radar track showing that plane doubled back to Malaysia, coming close to two airports (Kota Bharu and Penang), before retreating to international waters. That is hugely revealing and by itself renders most of the theories that were discussed for weeks and even months later moot (accident, theft, hostage-taking). This information was revealed by Malaysian military officials very early on, although it was clear that they considered it “sensitive.” The leaks informed some early reporting, including a March 14 chart which appeared in the New York Times, which we now know to be basically accurate regarding the plane’s trajectory:
http://www.nytimes.com/interactive/2014/03/14/world/asia/flight-mh370-map-update.html
The unreliable narrator at the heart of this tragedy, Defense Minister Hishammuddin Hussein, failed to endorse the information for months, allowing bogus, red-herring explanations for the plane’s disappearance to thrive and drown out the obvious questions: why did this plane return to Malaysia? why wasn’t it challenged? and, why didn’t it land? I doubt that outcome was an accident. It looks more like a highly successful exercise in political “damage control” to me.
D Hatfield and Luigi: If you look at it from the frame that things began to break down aboard the aircraft while it was yet over Malaysia, then we have it flying out over open water to buy time for Luigi’s process, with the turn south indicating a total collapse of the agenda for the diversion at IGARI and perhaps some sort of intervention that sent it to nowheresville. That the SDU began powering at 18:25 is indicative of a change in the general situation aboard the aircraft. The turn south was initiated shortly after the SDU booted up and is perhaps the result of this change of the general situation.
As for attempts to hide or skirt from detection by military radar, there isn’t any evidence of such behavior or intent. We can assume that there would be such intent based upon deactivating the transponder alone, but in fact there wasn’t any such behavior. Finally, the aircraft did not avoid detection by military radar systems.
@Rand
If the plane came in low, I think the most likely reason was to present the option to land at Kota Bharu or Penang, not to evade radar. Coming into Malaysia low would also be threatening for obvious reasons. Looks like a win-win.
VictorI posted that his conclusion is MH370 did not have the range to reach Dr. Ulich’s most probable impact location. In addition, the results of only a few tests do not confirm their validity for other situations. However, the fuel use rates I posted were all I could find to calculate range. (I think the test periods used for the rates in the Delta manual were too short to give meaningful results). It is very possible that the following methods are not valid but here is how I did them. Also, I did not include reserve fuel, temperature difference or PDA. I simply used the reported 43,800kg at 17:07 along with Dr. Ulich’s air distance of 3591nm over the 7.1333hr from 17:07 to 00:15.
The published fuel usage for a 2000nm flight at 40,000ft is 23,500 kg over 4.3166hr. These convert to 5444kg/hr at 463ktas and perhaps can be extrapolated to 5910kg/hr at 503ktas for 7.1333hr or an air distance of 3728nm? If these conversions are valid, they show that at FL400 there was enough fuel on board to travel 137nm further than Dr. Ulich’s impact location.
Following the same method but using 26,400kg for 4.75hr at FL300, I got a distance of 3279nm or 312nm fewer than necessary to get to Dr. Ulich’s location. Interpolating between this range and the 3728nm at FL400, I get approximately 3591nm at FL370.
I think this means that for the flight to reach Dr. Ulich’s impact location, using these results, it needed to be flying higher than the postulated FL350 for a significant portion of the flight.
The way it was explained to me is as the fuel is burned the a/c gets lighter (fuel represented more than 20% of the take-off weight of MH370) so less lift is required to maintain a given flight level. To compensate for the reduced lift requirements and without making any trim adjustments, the a/c can reduce speed or go to a higher elevation. Since the air is less dense at the higher elevation, the a/c needs to increase speed to create the necessary lift. Also, because the air is less dense, drag is reduced so less fuel is required to reach the higher speed at the higher altitude.
@Luigi
13,000 ft runway 03 with an ILS (approach from south/southwest) on Langkawi, Island was the best & only suitable option for a 777 emergency landing and was the closest to IGARI….with no radio and other problems on board. Kota Bharu was not a viable option.
@D Hatfield
This wouldn’t have been an emergency landing. This was about Malaysian politics, not an in-flight emergency.
@Luigi
Sorry, but a large amount of evidence points to an onboard landing emergency. When a pilot only has about 20 minutes to get that bird on the ground, how this pilot reacted, was precisely following all of his training.
No evidence from the flight to verify that it had anything to do with politics, except speculation.
@Luigi: weeks ago, Jeff explained to you why the wild altitude changes of which you are “reasonably convinced” were rejected by the IG: if you believe Dr. Bobby Ulich’s horizontal speeds, then I think the IG is saying that you must – MUST – reject any notion that the plane climbed from 10K up to 35K at any time during the turnback OR trip south – because you have to give up CONSIDERABLE horizontal speed (and fuel) to do so.
Near-500KTAS horizontal speed throughout = stable altitude throughout. Period.
If your “US intelligence” source was wrong about the cell phone tower, it wouldn’t have been the first time ever that anonymous US officials leaked wrong information.
Heck, it wouldn’t have been the first time that DAY (ref: acoustic ping authenticity)…
@Brock
I have seen no data to back up the claim that the plane couldn’t have maintained a high average speed while descending during the 16-minute overflight from Kota Baru to Penang, despite asking here several times. When I have searched for speed-altitude “doghouse plots” online, I have found several (I found none for the 777 or similar plane) that are indeed doghouse shaped and imply that max speed can actually be higher at low altitudes than at fuel-economy optimized cruising altitude. I’d like to see that plot for a 777, please.
No one has suggested that the plane flew changed altitude during the southern leg — that is a strawman and a red herring.
BTW, I notice that Ulrich’s chart has the plane traveling at over 500 knots (926 kph) after the diversion turnaround, while the ATSB paper has it going at 800 kph. It is, quite simply, a fantasy that the plane’s speed over time can be inferred with any great accuracy from the published data.
@Luigi,
Please provide reference and page number for your statement that “the ATSB paper has it going 800 kph” after diversion turn-around.
I am not aware of any published ATSB estimates of speed based on the radar track.
In Table 5 in the Appendix of their first report they use 867 knots ground speed at 17:07. This is for the last ADS-B data, and it corresponds to 481 knots true air speed. This is approximately 15 minutes before diversion.
It is not a fantasy to calculate the speed from diversion turn-around until last radar contact. It’s quite simple, and it is precise.
@Dr. Bobby Ulrich
See p. 20 of the Journal of Navigation paper. Speed at 18:25 – 800 kph. Speed at 18:39 – 800 kph. Speed at 19:41 – 800 kph.
D Hatfield: speculation is perfectly warranted and even indicated when engaging the What and the How of MH370’s disappearance. The location science does indeed need to avoid speculation and bring scientific rigor to the process establishing assumptions, but attempting to understand the intended destination for the diversion, whodunit and the motive requires a substantial amount of speculation.
I would suggest to you that there is no evidence whatsoever that this situation presents as one involving a mechanical failure from start to finish. Furthermore, a probability tree analysis favors that the intended destination for the diversion was Malaysia. As for the development of a mechanical failure requiring an emergency landing, there are all sorts of elements that reduce the probability of this occurrence, inclusive of no reported emergency radio contact, the timing of the diversion and – wait for it – the aircraft did not, in fact, attempt to make an emergency landing.
The aircraft had an intended destination at the point of diversion at IGARI: choose a couple and rank their probability…
Luigi: I rather go with the assumption that the aircraft did in fact maintain reasonably stable flight at approximately FL350, at least through to 18:22 and its concomitant location (if the primary radar information is in error, then this would need to be revisited). Meanwhile, I remain congruent with there not being any indications of an approach to Penang et al (as in the case for an emergency landing) to raise the probability of KL as the intended destination, which was a 20 minute flight from the a/c’s position south of a Penang upon the execution of a 90 degree approach leg turn onto a KL approach route.
@Luigi, All:
Luigi: Many thanks for posting Keith Bradsher’s 03.17.14 NYT article “Questions Over Absence of Cellphone Calls From Missing Flight’s Passengers”. It is not only highly illuminating on close re-read, but it prompted me to go back and re-examine some other articles by Bradsher.
All:
But before going on, please let me:
1. Offer a little #protip (in CAPS, because it can’t be emphasized enough):
WHEN SOMEONE TELLS YOU A STORY, PLEASE LISTEN FOR WHAT THEY SHOULD SAY THAT THEY DON’T.
2. Lay the foundation with another (theoretically unrelated to MH370) Keith Bradsher story first.
In July 2014 (after MH370 vanished), Keith Bradsher wrote about an incident that occurred in 2000, wherein a mysterious chemical (in canisters), found its way onto an MAS flight. The Malaysian government ended up digging a large hole in the ground near the airport tarmac and burying the entire plane.
What was quite notable (beyond the fact that MAS buried a ENTIRE airplane in the ground) is that Bradsher’s article did not specify that the canisters contained oxalyl chloride (a military poison) or better, how he knew that this shipment of chemicals was “destined for Iran”. http://www.duncansteel.com/archives/899#comment-9839
So I posed the Iran question on Twitter (and tagged Bradsher in it). His response:
“Malaysian who worked on the issue at the time said it was destined for Iran.”
https://twitter.com/nihonmama/status/499683382511431681
What Malaysian? Who?
And you have to wonder — why didn’t Bradsher include THAT very important tidbit in the article? How could he state where the shipment was headed but not state the source for that information? My initial reaction was that Bradsher was sloppy – and apparently, so were his editors. Now, however, I’m inclined to believe that when Bradsher’s articles are vague on key details, it’s intentional. Or perhaps the better word is, purposeful.
Back to the ranch.
In the NYT Bradsher piece that Luigi linked to, the hook is the absence of cell calls from the pax on MH370. But also embedded in that conversation is a discussion of the altitude story, namely that the plane was flying as high as 45,000 feet, which we’ve already noted, is beyond the *certified* maximum altitude for a 777-2.
I’d like to draw your attention to the following:
1. As far as I can tell, there have been no updates (or corrections) to this article — meaning that no one, from Boeing or elsewhere, appears to have come forward and stated that it was impossible for MH370 to have flown at FL45 — beyond it’s certified maximum. Bradsher sure never says it, nor does he even remotely imply that is the case. But he does lay out, based on conversations with experts (and with specificity), what would happen to those in the main cabin if the plane were depressurized at 45K: a total useful consciousness of seconds. The exact same thing my cousin the T7 pilot told me.
2. The paragraph that begins the altitude discussion starts with “According to military radar”. Again, I initially thought this was very sloppy, both in the writing and the editorial, because WHOSE radar was not specified. Of course, most people would just naturally assume that given the context, the writer meant MALAYSIA’S military and keep moving. But was Malaysia’s military the ONLY military that *saw* MH370 right AFTER its turn over the South China Sea?
3. “Many aircraft carry air phones using radio or satellite technology, and the Malaysia Airlines jet was equipped with THEM (CAPS mine) in business class.”
What is “them”? It’s vague. Why didn’t Bradsher just clearly state that MAS business class comes equipped with SAT phones? We certainly know this to be the case, because that information was sitting right on the MAS website.
[When I tweeted a link to the MAS website on May 20, the page was still up. It was deleted sometime AFTER that.]
4. “If someone deliberately diverted a plane and turned off its transponder and other communications equipment, that person is likely to have disabled the in-flight entertainment system so that passengers could not figure out from the map that they were flying in the wrong direction.”
Note the use of “likely to have”.
If Bradsher had rung up some random Joe telco, Joe wouldn’t be able to say that the IFE system was “likely” to have been disabled, although though he might have speculated that that could have happened.
But it seems clear that the source of this hypothetical statement was not a random Joe. It was a telecommunications expert “who assisted on anonymity because he was not authorized to talk to the news media.” Not authorized to talk to the media. That means that Brasher’s source was/is an INSIDER – either involved directly with the investigation of MH370 or privy to inside information. Who said that the IFE system on MH370 was “likely” to have been disabled. In the world of politics, people would call that a leak.
After reading the Bradsher article Luigi posted, I was prompted to re-visit another Bradsher article I’d tweeted. It’s dated June 23 (and filed from Canberra): “Malaysian Jet Was in Controlled Flight After Contact Was Lost, Officials Suspect” http://t.co/I0ZLl2FF8f
From the article:
“Their conclusion, reached in the past few weeks, helped prompt the decision to move the focus of the search hundreds of miles to the southwest…
The main evidence for the conclusion lies in a re-examination of Malaysian military radar data and in a more detailed analysis of electronic ‘handshakes,’ or pings…
…a comprehensive international review has found that the Malaysian radar equipment had not been calibrated with enough precision to draw any conclusions about the aircraft’s true altitude.
‘The primary radar data pertaining to altitude is regarded as unreliable” said Angus Houston…Martin Dolan, the chief commissioner of the Australian Transport Safety Bureau, agreed with Mr. Houston. ‘There’s nothing reliable about height’…
Mr. Houston and Mr. Dolan declined to discuss any details about the Malaysian radar readings…
SO THE DISMISSAL OF THE RADAR ALTITUDE DATA PROMPTED A CHANGE IN THE FOCUS OF THE SEARCH.” (CAPS mine).
Did you get that?
Without a peep (in that article) from any Malaysian officials, and from the pulpit in Australia — sans any details as to who conducted the “comprehensive international review” of Malaysia’s military radar system — or an explanation of the technical basis for determining that Malaysia’s system was not “calibrated with enough precision” — it was announced that Malaysia’s military altitude data was so imprecise that it was being dismissed. Which then allowed the authorities to CHANGE the SEARCH focus.
Other than Keith Bradsher, is there an aviation journalist anywhere on earth who caught this – or questioned it (or the authorities in AUS) in any meaningful way?
I’m also guessing that Anwar Ibrahim was probably surprised as hell to hear that the authorities in Australia found Malaysia’s radar system to be wanting for precision — because he gave a video interview to The Telegraph in April, wherein he stated:
“that he had personally authorised the installation of ‘one of the most sophisticated radar’ systems in the world, based near the South China Sea and covering Malaysia’s mainland and east and west coastlines, when he was the country’s finance minister in 1994.”
“We don’t have the sophistication of the United States or Britain but still we have the capacity to protect our borders.”
http://t.co/zaLSdT57mx
https://twitter.com/anwaribrahim/status/451963491105374208
So Malaysia ponied up what had to be some major coin for a sophisticated Marconi radar system, but didn’t bother to keep it calibrated?
Oh, OK.
I’ll just leave you with Duncan Steel’s cutting (and I’ll wager, very likely spot-on) observation:
“Sorry if I am doing them an injustice, but I would think that the JACC/AMSA is just plotting up the information/possible tracks that they seem to get from the NTSB and then picking areas nearby to search. In that regard the RAAF and AMSA is just acting as a wholly-owned client state of the US, which is likely for the best in this connection: I do not believe that they have the intrinsic ability to do anything useful and value-added themselves, apart from fly search aircraft around the Indian Ocean.” http://www.duncansteel.com/archives/549#comment-906
A wholly-owned client state of the US.
As promised yesterday, have just submitted here an extended (follow-on) piece, which will take time to post because it contains multiple URL’s.
I’ve also posted it on my Twitter TL, for those who are there.
I put on my anorak and took a closer look at the 18:25 to 18:28 BFOs, just because they’re interesting:
18:25:27 142
18:25:34 273
18:27:04 176
18:27:04 175
18:27:08 172
18:28:06 144
18:28:15 143
Source, ATSB Journal of Navigation paper, 14 September 2014, p. 3
AS the paper notes, there is a sharp spike in the BFO during this interval. The authors consider the spike unexplained, saying:
“The spike in the measured data at 18:28 is not fully understood and was originally ascribed to a possible manoeuvre of the aircraft: although it could be related to frequency changes during the logon sequence described in Section 3.3.”
The discussion in Section 3.3 actually deals with BTOs, not BFOs. The authors explain that they found it necessary to introduce offsets to some of the BTOs and discard others as unreliable. They proffer the explanation that a combination of fixed and variable latencies in the signaling path during the logon sequence justify that choice. That is not backed up with any detail or data, but it doesn’t sound particularly implausible: empirically-determined latencies are built into the BTO model from the get-go. Things get more hand-wavy regarding any possible impact on BTOs — why should the system frequency-hop in the middle of communication? They don’t address the issue directly, but there is a vague reference to “the terminal switching channel and frequency during logon.”
Maybe the BFO spike around 18:25-18:28 is just an artifact of the signaling path. I believe the only other BFO they discard is the final one (00:19:37), which displays a whopping -184 point shift relative to the penultimate one, just 8 seconds before. I believe commenters here have preferred to take the BFO at face value, as indicative of a very high speed descent associated with the plane falling out of the sky. The shift is certainly in the right sense (negative). It is *huge* — about an order of magnitude higher than the positive offsets associated with the climb to cruise from take-off. But, maybe that’s actually right and reasonable.
Getting back to the 18:28 data, what if we go with the option that the BFO shifts reflect real changes in the plane’s motion? If so, the pilot pulled a “manouevre” within minutes of leaving military radar coverage and rebooting the satcom. And, that seems perfectly intuitive and reasonable — the flight was entering a new phase at this very time.
What kind of manouevres are consistent with the BFO spike? Note that, because the spike is apparent in a short burst of transmissions, if it’s not from the signaling path the spike must come from the movement of the plane, not the satellite.
We can exclude a descent or dive as the sense of the spike is wrong. Lines 2 and 3 of the table on p. 20 of the report tells as that upward motion (with a strong line-of-sight component toward the geostationary satellite, high in the sky) yields a positive shift in BFO.
A turn is probably also ruled out. The BFOs bracketing the spike are 142 (before) and 144/143 (after). If the plane made a substantial heading change, altering the uncompensated component of the velocity vector with respect to the true speed/position of the satellite, the BFO spike should instead be a step function. Now, I suppose it’s possible that there is a latency in the incorporation of speed/heading date into the plane’s frequency compensation circuitry — in which case a turn might show up as a BFO transient. Still, I’m not aware of anyone proposing a major turn occurred at this point in the flight (e.g., the southward turn). So, a turn seems possible but unlikely.
The spike is compatible with the initiation of a climb concomitant with the satcom reboot. However, it could not have been a long, slow climb comparable to the normal climb to cruise after take-off. If the plane were still climbing at 18:28, the BFOs would not have returned to their 18:25 values — the circuitry does not compensate frequency for vertical motion.
The magnitude of the spike can be compared to the errors in the p. 20 table to estimate the vertical velocity component. The line 2 & 3 errors are 20 & 34, representing normal climb speed (~1500 fpm?). The spike delta is about +130 at 18:25:34 (~7500 fpm? — probably about as fast as a 777 can climb, pedal-to-the-metal), but drops to a more normal ~30 (maybe 2000 fpm?) about 90 seconds later. One minute after that, the ascent has basically stopped.
Doing a very approximate integration over time, if the BFO spike is due to aircraft motion, then it’s probably representative of a rapid climb in which the plane’s altitude increased by on the order of 8000 ft in under 3 minutes. Certainly doesn’t seem impossible.
Have fun…