Earlier today, the Australian Transport Safety Board released a document entitled “MH370 — Search and debris examination update.” Perhaps occasioned by the recent completion of the towfish scan of the Indian Ocean seabed search area, the document updates earlier ATSB reports and offers some intriguing insights into what may have happened to the plane. Some thoughts:
— The first section of the report expands upon an assertion that the ATSB made in an earlier report: that the BFO values recorded at 0:19 indicate that the plane was in an increasingly steep dive. Indeed, the newly published calculations indicate that the plane was in an even steeper dive than previously reckoned: between 3,800 and 14,600 feet per minute at 00:19:29, and between 14,200 and 25,000 feet per minute at 00:19:37. On the lower end, this represents an acceleration along the vertical axis from 37.5 knots to 144 knots in eight seconds, or 0.7g. On the higher end, this represents an acceleration along the vertical axis from 140 knots to 247 knots, likewise about 0.7g. If the plane were freefalling in a vacuum, its acceleration would be 1.0g; given that the airframe would be experiencing considerable aerodynamic drag, a downward acceleration of 0.7 would have to represent a near-vertical plunge, which a plane would experience near the end of a highly developed spiral dive.
— The second section describes end-of-flight simulations carried out in a Boeing flight simulator in April of this year. These tests were more detailed than others carried out previously. Evidently, modeled aircraft were allowed to run out of fuel under various configurations of speed, altitude, and so forth, and their subsequent behavior observed. Thus, the exercise modeled what might have happened in a “ghost ship” scenario. Notably, it was found to be possible for the plane to spontaneously enter the kind of extremely steep dive described in the previous section. This being the case, the report states, the plane “generally impacted the water within 15 NM of the arc.” This is not surprising, considering that the plane had already lost altitude and was plummeting straight downward. This offers a tight constraint on where the plane could plausibly be if the 0:19 BFO analysis is correct.
— The third section describes the results of debris drift modeling that has been informed by tests involving replica flaperons “constructed with dimensions and buoyancy approximately equal to that of the recovered flaperon.” An important point not addressed by the report is the fact that the French investigators who tested the buoyancy of the flaperon were unable to reconcile its observed behavior with the observed distribution of the Lepas anatifera barnacles found growing on it. So when the French ran their own drift models, they had to run them twice, one for each buoyancy condition. Apparently the Australians overcame this paradox by discarding one of the states.
— The third section notes that, according to modeling carried out by the CSIRO, debris which entered the ocean in the southern half of the current search area would not likely reach Réunion by the time the flaperon was recovered. Meanwhile, debris that entered the water significantly north of the current search area would reach the shores of Africa much earlier than the time frame in which pieces were actually discovered there. Using this logic, the report concludes that the northern part of the current search area is probably correct. However, this seems dubious reasoning to me: one would expect a gap between the time debris arrives in Africa, and the moment when it is discovered. Also, debris can move quickly across the ocean, only to be trapped in a local gyre and move around randomly before beaching. Therefore I think the argument that the pieces couldn’t have originated further north is flawed.
— The fourth section, describing the damage analysis of the flap and flaperon, is the most interesting and newsworthy of all. In short, it makes a persuasive case that the flaperon and the inboard section of the right-hand outboard flap (which, rather remarkably, turn out to have been directly adjacent) were in the neutral, non-deployed state at the moment of impact. Assuming this is correct, this eliminates the IG’s flutter theory, as well as the widely discussed theory that the flap was deployed and therefore indicative of a pilot attempting to gently ditch the plane. Proponents of these theories will continue to argue on their behalf but in my opinion they were dubious to begin with (given the shredded condition of much of the recovered debris) and are now dead men walking.
— No mention was made of Patrick De Deckker’s exciting work with Lepas shells.
— Overall, the thrust of this report is that the plane went down very close to the seventh arc in a manner consistent with a “ghost ship” flight to fuel exhaustion, exactly as the ATSB has assumed all along. There is, however, one very large elephant in the room: the fact that Australia has spent two years and $180 million demonstrating that the plane’s wreckage does not lie where it would if this scenario were correct. Therefore it is not correct. The ATSB’s response to this conundrum is rather schizophrenic. On the one hand, it has recently floated the idea of raising another $30 million to search further—presumably the small remaining area where a plane just might conceivably have come to rest in a ghost-ship scenario, as I described in an earlier post. On the other, it has today convened a “First Principles Review” consisting of experts and advisors from Australia and around to world to scrap their previous assumptions and start with a clean sheet of paper. This implies an understanding that they have proven themselves wrong. I wonder how many assumptions they will scrap. Perhaps, as Neil Gordon mused in his interview with me, that the plane wasn’t really traveling south at 18:40? Or perhaps they’ll dare to go even deeper, and contemplate the provenance of the BFO data… ?
— A postscript: Richard Cole recently posted an update of the seabed search (below). I’m intrigued by the fact that the Fugro Equator has deployed its AUV near the northern end of the search zone. When I interviewed him for my last blog post, Fugro’s Rob Luijnenburg told me that the northern end of the search zone was flat enough that it could be scanned by the towfish alone; there was no need for an AUV scan to infill the craggy bits. So why is the AUV looking there now? Especially given that it’s very close to an area just reinspected by Dong Hai Jiu 101’s ROV. Another MH370 mystery.
UPDATE 11-2-16: I emailed Rob Luijnenburg and he immediately responded: “The AUV is scanning in a section in the north part of the priority search area in the very rugged terrain south of Broken Ridge (the east -west mountain range at approximately the 33rd parallel)… Generally the AUV is deployed in spots of extremely rugged seabed to complete the 120,000 sq km priority area survey.” Worth noting is that if the search gets expanded northeastward, it’s going to be into very rough terrain indeed.
@Johan
The 18:25:27 BFO value of 142Hz is exactly what you would expect it to be given a plane flying along the Mekar to Nilam air corridor. It is the BFO value 7 seconds later at 18:25:34 of 273Hz that is off the charts. Likewise the BTO at that time is not plausible. I am prepared to write that value off as an equipment anomaly of some sort.
@buyerninety
To add, I argue that if the plane was at an altitude of ~30.000ft on 00:19.25 it could not have reached the water surface by far after ~1 minute at a descend rate of 14.600ft/m on 00:19.37. At that descend rate it would have descended ~1900ft in those 8 seconds between 00:19.25 and 00:19.37 I argue.
The expected IFE log-on request that did not came a minute after ~00:19.25 does not have to indicate the plane crashed in that minute.
For that to happen the descend rate had to be a lot higher than 14.600ft/min at and after 00:19.37 IMO.
00:19.29…
@DennisW
“I am prepared to write that value off as an equipment anomaly of some sort.”
You could prepare yourself to enter your own whacko list.
Wasn’t trying to be rude. Just throwing it back.
@David, Yes, it seems that the Australians are in full-scale walk-back mode from the idea that they’d try to get a $30 million extension to the seabed search. The impression was reinforced during Wednesday’s press conference (Transcript: http://minister.infrastructure.gov.au/chester/interviews/2016/dci011_2016.aspx). It raises the question of what the three-day reassessment conference is for, if they’re not going to do anything with the results. Still, I’ll be curious to hear the results.
BTW it seems to me that the ATSB is deliberately fostering the misimpression that there is still 10,000 sq km left to search. I suspect that the motive is to avert questions about why they have allotted themselves as much as four months to search (via the good-weather season) a quite small area of seabed. The uncomfortable answer being that they are stalling.
@DennisW, I’d like to grapple with this topic for a bit. To recap earlier comments, the Ashton (Inmarsat) Journal of Navigation paper includes this statement: “Detailed analysis of BFO samples taken from other flights showed a high degree of consistency for the signalling message frequencies, with the exception of those that were performed immediately after the initial logon process. This called into question the BFO measurements after the log-on sequences at 18:25 and 00:19. However it was also determined (by the same method) that the first message transmitted by the aircraft in the logon sequence, the Logon Request message, did provide a consistent and accurate BFO measurement.”
This would seem to answer your question about the uncanny normality of the 18:25:27 BFO value: The logon request was totally normal, because the first returned value is usually normal after an SDU reboot. It’s just the ones after that that are skewed as a result of the oscillator being cold.
So the head-scratcher is: Why doesn’t the oscillator’s coldness throw off the frequency of the first transmission, too?
@Jeff
That is exactly why I do not believe the oscillator was cold or recovering from a recent power cycle. The 18:25:27 BFO is perfect (relative to where the best estimate of aircraft track, ground speed, and location were at that time. The next BFO value at 18:25:34 is divergent by some 130Hz. Likewise the BTO at 18:25:34 is clearly bogus by a very large amount.
The oscillator had to be “on frequency” at 18:25:27 to produce the observed BFO.
Just a comment from the peanut gallery:
How many billions have now been spent in this effort? How to replace the many lives lost and families destroyed?
A $25 web camera with modern technology would have saved us all a lot of trouble.
Because we are still putting our loved ones on planes with technology from the 1950’s.
Because the airlines have to make a buck off our safety, right?
It illustrates a complete lack of safety standards for the flying public. Could we please at least update modern tracking and safety to the 21st century? Or is Man just too incapable of real evolution?
@DB, There was a lot of sophisticated and expensive technology on MH370 to keep track of it. The 777 is an eminently safe, reliable plane. However, as has now become clear, someone intentionally sabotaged that technology. That’s why the plane is missing, not because of a lack of safety standards.
@airlandseaman, Would love to hear your thoughts on this.
@ DennisW
Sorry dude but a great deal of folks have relied on your valued “expertise”‘ over the period and now you’re badly wavering around interpretation around offset and reboot values when recently (& strongly) challenge all aspects of your assumptions – so that you might (lazily/conveniently) blame ZS?. Wacko
@GortoZ
My BFO observations have nothing to do with blaming Z. They are what they are, and are scenario agnostic except for the conclusion that a decompression event was extremely unlikely to have occurred before 18:25.
Having said that, I strongly believe that Z is the perp.
@DennisW
Re your “bto-games” edit of 1Nov16, just out of curiosity, to satisfy “an itch” on my part, what BFO’s do you get for 18:25, if position was 1.95N 96.1E True Track 238 for ground speeds:-
(a)480 (b)490 (c)500 and (d)510 knots.
@Dennis/all
If a decompression event happened, it does not necessarily mean the electronic equipment gets cold. On Helios believe they were getting ACARS messages re: some equipment over-heat. The reason for this is that the thin air has less cooling capacity/mass.
In any case the air potentially cools instantaneously upon rapid depressure but the interior solid surfaces are still at room temp and would start to heat the air back up, unless there was continuous flow of -40C air from outside (slower process).
@Ventus
(a) 98Hz
(b) 97.5Hz
(c) 97Hz
(d) 96.5Hz
@DennisW
Many thanks.
Off to bed to sleep on it (2:30am here) !
@Ventus
BTW, if the aircraft were stationary the BFO at your location would be 124Hz. So most of the Doppler is due to the motion of the satellite relative to the aircraft.
@DennisW
Do I understand you well when I suggest that if the first BFO value at 18:25:27 had been 273Hz and the second one at 18:25:34 142Hz this could have been an indication of a very cold SDU at 18:25:27 that warmed-up in those 7 seconds decreasing the value with 131Hz but not the other way around?
Could the BFO value measured at 18:25:34 of 273Hz then also be the result of an assumed fast and steep descend like the 00:19:37 BFO value which took 8 seconds starting from 00:19:29 instead of 7?
I mean in my view those pairs of BFO values (18:25 and 00:19) look quite similar in this regard.
Could their be a relation? A similar cause?
Both a fast and steep descend maybe?
@Ge Rijn
I think of the 273Hz BFO and the corresponding BTO of 51700us as anomalous. The oven cannot change temperature fast enough to produce BFO values that far apart in 7 seconds.
The increase in BFO over that time period (if you believe the values which I do not) can only be accounted for by aircraft motion. Victor postulated a maneuver which accounts for the increased BFO, but cannot account for the BTO value which should lie in the vicinity of 12500us.
@DennisW, Thanks for your earlier reply. Am reading through Inmarsats report as well to better understand the too perfect 142 BFO. Lots of wine needed to process but very interesting stuff. In the case of ZS, I doubt he had any knowledge on BFO. If anything, he would have been more worried about the black box pinging incessantly for a month. , IMO. The events between 18.25 and 19.40 remain a mystery.
@Keffertje
I had been avoiding working on the flight path between 18:25 and 19:40, and have only recently given it detailed attention. Probably reflects on not having anything better to do relative to the flight.
@Gysbreght
–“That’s just silly. What would you say if I challenged you to find an instance where a detached turbofan damaged a flaperon in a ditching scenario? Then there is also the outboard flap. Was it also hit by a turbofan?”
Dig yourself into holes much? What would I say? I’d say I’ve already done exactly that. Twice.
In this thread I named two instances of a detaching engine trashing the trailing edge in a ditch. Maybe you were too busy Googling irrelevant diagrams to notice.
In one instance, there is clear video of the engine being ripped backwards with – as I also said before – the force vector of the crash which, in the case of Eth961, is straight backward with the flow of water. It just so happens the entire wing went too. But prior to the wing separating, you clearly see where the engine goes straight back underneath the wing.
In the other instance, US1549, the entire flap section of the left wing from mid-chord inward, is missing.
And was the outboard flap section of MH370 dinged by a turbofan? For about the millionth time, no. And neither was the flaperon. That’s what I was saying for over a year when a time-sucking debate about which way the engine detaches was spawned.
So back to my original point: Don’t compare AF447 end-of flight with MH370.
And with that, my total time with you has expired. Peace out!
@DennisW
Thanks for the extra explanation.
I too think a -50C SDU and consequently (depressurized) cabin/cockpit are very unlikely for it would mean the plane was allready not actively piloted before ~18:21.
The FMT would be impossible unless it was pre-programmed before 18:21 in this case IMO.
And I also thought 7 to 8 seconds to warm-up the crystal would be too short but didn’t know for sure.
I’m just trying to figure this out more.
Leaves the 00:19:37 BFO/BTO. You also believe those are anomalous? Why if so?
A bit contradicting (imo) you say the increase in BFO over that time period can only be accounted for by aircraft motion (which you don’t believe I conclude).
But what kind of aircraft motion could this have been where you don’t believe in?
@Ge Rijn
The BTO difference between 19:29 and 19:37 is too large – some 26000us. Totally not possible physically. Anyone putting trust in the 19:37 ISAT data (and we know who they are) is out to lunch. The BTO is clearly flawed. Why believe the BFO?
I would be inclined to put some trust in the 19:29 values.
@Ge Rijn
A descent rate on the order of 3800-4000 fpm implied by the 00:19:29 BFO value is not considered out of the ordinary. It in no way implies an uncontrolled descent as being extolled by the ATSB and others. The 00:19:37 BFO value is just plain untrustworthy, and no conclusion can be drawn from it.
@DennisW
Then I conclude from your point of view the 18:25:27 BFO/BTO values and the 00:19:29 BFO/BTO values can be trusted but their 7 to 8 seconds later quite similar BFO values must be anomalous in regard to the BTO values or both must be anomalous.
Still they are measured.
I ask you again; what kind of aircraft movement could have caused these anomalous data? None?
@DennisW:
Got ya. Many thanks.
@Ge Rijn
Yes, I think the first values can be trusted in both cases, and the second values are highly suspect.
Victor did some analytics relative to the 18:25:34 BFO value. You should check those out, but basically that situation required a positive rate of climb to explain the 130Hz or so BFO increase.
In the case of the 00:19:29 BFO, a negative rate of climb of some 3500fpm or so can account for the 70Hz or so of BFO decrease.
@all
Just an aside relative to the sorts of statements that drive me bonkers. From page 9 of the latest ATSB publication:
“A statistical analysis of the BFO error from all the 20 previous flights of 9M-MRO identified that the distribution was approximately Gaussian (see DST Group book – link above) with a standard deviation of 4.3 Hz. ±3 standard deviations (12.9 Hz) is a conservative choice for the error.”
While the error histogram plotted in the DSTG Book does indeed resemble a Gaussian distribution, the element of time is totally ignored. The distribution of oscillator errors early in the flight will be much smaller than the distribution of oscillator errors later in flight. To plot a histogram of all the errors and compute a variance is meaningless since the variance is not constant, but grows with time. What the DSTG approach essentially does is to over estimate errors early in the flight and underestimate errors later in the flight. The error distribution is not stationary nor is it ergodic both of which criteria are implied by a simple minded Gaussian model.
While the DSTG guys were at least clear about what they did we have the Inmarsat statement of a +/-7Hz BFO error bound. What in the world is that supposed to mean? Does it mean that the error is uniformly distributed over a region of +/-7Hz? Is 7Hz supposed to be a 2 sigma value of a Gaussian? The reality is no one knows what they meant.
@DennisW
Regarding the 18:25:34 BFO there was not a positive increase in climb but a steep descent just like the 00:19:37 BFO.
If those data are anomalous there was no steep descent after 18:25 or after 00:19:29.
If only the 00:19:29 BFO/BTO is thrustworthy there is a descent of 3800ft/M which is a glide descent. Not a dive or otherwise.
Your thoughts?
While on this subject, can I go back to their report and see (did they publish) flight data on the 20 prior 9MMRO flights (dates/routes) used? The wording in some places seems to suggest 20 selected prior flight vs. the last 20 flights…not sure.
I’d like to know the flights. Apparently from Gilbert’s paper there were 100 9MMRO flights between Jan_2014 and 8-March reflecting the need to top off O2 from 1120 to 1800 psig.
@Ge Rijn
In order to make sense of the 18:25:34 BFO a CLIMB is required. In order to make sense of the BFO at 00:19:39 a descent is required. At 18:25:34 the aircraft must move in a direction toward the satellite. At 00:19:39 the aircraft must move in a direction away from the satellite.
I don’t know where you are getting a steep descent at 18:25:34, but that is wrong.
Yes, I agree that the descent at 00:19:29 is in the realm of the ordinary.
In both those cases the airplanes ditched with a relatively low rate of descent. In those conditions it is quite possible that wing-mounted engines “drop downwards and away”, as buyerninety puts it.
The condition I was addressing and you commented on Nov.2 at 4:10 PM was: “…hitting the sea in a nose-high attitude at high rate of descent, similar to AF447.”
Sorry if I misunderstood what you meant when you wrote on Nov.2 at 4:11 PM:
I honestly don’t see why not. AF447 resulted from the PF holding the sidestick fully back, causing the stabilizer and elevator to go the full nose-up position. You are quite right that engine thrust contributed to the nose-up pitching moment, but without that contribution the pilot input on the stick would still have held the airplane in a stall. If the autotrim system in a B777 is similar to that in the A330, a similar condition could have existed in MH370’s end-of-flight scenario.
If anyone is still interested in the loads imparted on the engines in that crash condition I would recommended that he reads the AF447 Final Accident Report.
@Jeff:
“The logon request was totally normal, because the first returned value is usually normal after an SDU reboot. It’s just the ones after that that are skewed as a result of the oscillator being cold.” Etc.
I am not sure if the article says so or if this is your interpretation (the sentence you are quoting seems merely to state a description of the facts given), but there you have a perfect question to put to Inmarsat. One might guess they stayed in shallow waters for a reason, but someone there ought to have a clue about the off-the-charts value.
@Jeff Wise. “..the Australians are in full-scale walk-back mode.”
Two possible explanations:
-the intention all along was to conduct a review to determine there was a case for a new search and the PM report misconstrued it ie there is no walkback.
-the statement in the PM report, unattributed, that the outcome intended,”will make it impossible for Malaysia and China to back away from” being both presumptive and tactless (with reps from those countries attending), seriously embarrassed both ATSB and government.
-progress at the Review was not as expected.
I favour the first, the second being the reason for publication of the “Correcting the Record”.
On recount, three.
@David
Progress? What could you possibly apply that term to?
Case for a new search? There was never a case for the original search.
Seriously embarrassing applies to all parties involved in this debacle – Australia, Malaysia, and China.
@DennisW. As I understand you, in view of the paucity of information and ambiguities, there should have been no search?
@David @ Dennis Don’t you think that people in general are underestimating the value of all this new Bathymetric Survey data to the Australian off-shore resource industry. Aircraft wreckage?? What aircraft wreckage??
@David
Yes, to spend that amount of money on ambiguous information was very ill advised. There is still not enough clarity relative to a terminus to initiate an underwater search.
The latest ATSB publication was an insult to anyone with a brain. The Aussies would be well advised to let the current plan run its course, and go back to doing whatever it is they do in Australia.
Previously thread I posted this table:
@Keffertje
Some Z dates from FI and Flight Sim
03-Feb: Last save of SIO simulator data
20-Feb: MS Flt Sim FSX removed from Disk
21-Feb: Z Flight KLIA to Beijing
26-Feb: Z Flight KLIA to Melborne
03-Mar: Z Flight KLIA to Denpasar (with Fariq?)
07-Mar: Z check-in at KLIA for Beijing
I have now found a listing of prior 9M-MRO flights.
http://i.imgur.com/UUW6ReX.png
So I am thinking like Z might have flown that 21-Feb flight to Beijing (actually 22-Feb flight). The 21-Feb is the date given in the FI for the video of Z at check-in at KLIA for Beijing.
I see nothing else of immediate interest to me, but it does look like 9M-MRO also went to Beijing and back on 7-March (not with Z). I see the times Z flew 9M-MRO as 8-March and possibly 22-Feb back in 2014. Prior to 22-Feb I don’t have Z’s prior flight history.
@all
From Reddit someone makes argument for FL450 from the radar data at IGARI…suggesting the squiggles in the U-turn are actually 10-sec radar sweeps
https://www.reddit.com/r/MH370/comments/5b5sm2/did_the_plane_fly_to_45k_feet/?st=iv4mgu9b&sh=d538e77c
Updated listing:
Some apparent Z and 9M-MRO history dates:
03-Feb: Last save of SIO simulator data
20-Feb: MS Flt Sim FSX removed from Disk
21-Feb: Z Flight KLIA to Beijing (9M-MRO 22-Feb)
23-Feb: 9M-MRO Service Maintenance A-Check
26-Feb: Z Flight KLIA to Melbourne
03-Mar: Z Flight KLIA to Denpasar
07-Mar: 9M-MRO to Beijing and back (w/o Z)
07-Mar: 9M-MRO Crew Oxygen top-off to 1800 psig
07-Mar: Z check-in at KLIA for Beijing (9M-MRO 8-Mar)
So it appears Z went to Beijing 22-Feb on 9M-MRO (after deleting MS FSX Flight Sim on 20-Feb). Next day, 23-Feb, 9M-MRO has maintenance (per Wikipedia). Then on 7-Mar, 9M-MRO makes round trip to Beijing, gets O2 top off at KLIA to 1800 psig, then picks up Z for fateful trip on 8-March MH370.
I am not certain of all that (needs verification), just what I gather from putting together FI + Sim Data + 9MMRO History.
@TBill, Thank you for posting that and good find on the details. I have given an earlier statement some thought, that a flight to Europe would have been easier. IMO, that would have changed the PAX nationality make-up. Hijackers/ZS may not have wanted the wrath of a European country/countries on them such as funding search efforts, or taking over the investigation? Not if the intent was not to be found, or to make it very hard or other reasons. Whoever hijacked M9-MRO gammbled on China and Malaysia doing zilch and therefore was the perfect flight?
Regarding the 18:25:27 BFO being 142 Hz, recall that this value was measured with a different channel (R8) than was used for much of the other BFO data (the arcs from 19:41 to 00:11 are R4). When the channel-to-channel offsets are applied, the value at 18:25:27 is reduced about 4 Hz. Thus there is actually no “exact agreement” with the expected value.
It appears very difficult (but possible) for a B777 to generate a BFO of +273 Hz. Certainly this would not occur when auto-piloted. This anomolous value at 18:25:34 might be a “feature” of a subtle software effect in the SDU. Note that when the calculated BFO frequency compensation is not changing rapidly, such as when the SDU logged on when stationary at the gate, the second “acknowledge” message had a (second) BFO that matched the (first) BFO of the log-on request message ~8 seconds earlier. It is only when the aircraft is flying (and probably turning) that the two BFOs (i.e., the “log-on request” BFO and the “acknowledge” BFO) are markedly different. I have suggested that this might be because the SDU does not recalculate the frequency compensation term for the “acknowledge” message only. ATSB will not answer my inquiry on this theory. Ashton at Inmarsat said he would “look into it” but I have heard nothing since. I would also note that even if this theory is true, you would not get a big jump in BFO unless a turn was also underway at the time (which appears likely at both 18:25 and 00:19). In other words, perhaps the change in calculated frequency compensation over 8 seconds could produce the large observed BFO change.
To me the match of the 18:25:27 BFO with the extended radar track implies that one of two things must have happened: (1) the SDU was not undergoing a “cold-oven start” then, and thus there was no OXCO “warm-up” effect at that time, or (2) the warm-up effect was completely cancelled out at 18:25:27 by a simultaneous rapid descent at more than 7,000 fpm that subsequently went to a nearly zero rate of descent 7 seconds later at 18:25:34. This is about 0.5g average vertical deceleration, which is certainly possible, but the timing coincidence (within a few seconds) of such a maneuver with the satellite data seems rather unlikely. Perhaps the SDU log-on itself at 18:25 was impacted by an effect other than simple power restoration, and the OXCO oven was already/still warm at that time. I don’t recall any of the BFOs from the KLIA gate showing any large positive deviations. Why didn’t they show a 130 Hz increase over the steady-state value if the first of these was a “cold-oven start”? Could this be caused by the fact that the OXCO oven was already warm and stable before the first transmissions were made at the gate? Does the SDU wait on inputs from other equipment (such as ADIRU) before logging on? If this happened at the gate, could something similar have occurred near 18:25 that caused a logon to be initiated then? We don’t know if, much less when, power to the SDU was lost between 17:07 and 18:25. I suspect the OXCO is itself very insulated thermally (by design) from the exterior environment. This allows the oven to be internally warmed up very quickly (in a few minutes), but it also prevents the oven from passively cooling off rapidly to the temperature of the exterior environment. In other words, the thermal time constant of crystal cool-down when unpowered is very much longer than a few minutes, possibly even longer than an hour. Depending on if/when SDU power was lost, the oven temperature at 18:25 might still be warm enough to allow a much more rapid stabilization (a “warm-oven start”) than would be the case with a “cold-oven start”, resulting in a much smaller BFO deviation.
@DennisW. The question to my mind is not whether the three countries (with overseas help) had enough information to begin the search but with the information they did have, which included very innovative material, whether they could justify not searching.
This is not Silicon Valley venture capital: it has political and social dimensions and there also are reasonable expectations from the international community, ICAO etc.
The prospects were stated as high, though some might have had reservations. Some of that was enthusiasm – and all is history. There is a long list of unsuccessful maritime searches and this one is miles from anywhere in a testing maritime environment with undersea gorges. Still, more evidence was and remains needed to resolve what happened and the wreckage is right now the best hope for that even if more than elusive.
The three countries with helpers have ‘given it a go’ and I hope (evidently like the ATSB) reasonable grounds will be found to fund search continuation as needed. That might be now or after further research, that effort continuing until the wreckage is found or reasonable prospects are exhausted.
For Australia’s part this would be consistent with the advice you give, to, “go back to doing whatever it is they do in Australia.”
“The latest ATSB publication was an insult to anyone with a brain.” Fortunately you have made earlier comments in support of that characterisation. However of itself it is no more helpful than observing its likeness to mass Glock ownership.
@Keffertje, “Hijackers/ZS may not have wanted the wrath of a European country/countries…”
I know what you mean but leaving aside some very aggrieved Chinese and Malaysians, other passengers included:
7 Indonesians
6 Australians
5 Indians
4 French
3 Americans
2 each from New Zealand, Ukraine and Canada
One each from Russia, Taiwan, Netherlands
Two men – one confirmed as Iranian – travelling under stolen Italian and Austrian passports
Source: Malaysia Airl
The search has not yet been stopped and if it is more likely that will be from prospects than funds, IMO.
@David, Thank you for posting. What we know so far is that MY and CN don’t care. MY wants it to go away, and CN…well has not contributed much either. That NOK is grievedgoes without saying. My point was: if PAX were 90pct. European (flight to Europe), I know for sure they would have responded differently (and acted differently) than what we have seen from MY and CN.
@All (@DrBobbyUlich)
Some very interesting assertions over on http://www.seventharc.net/
today about the width of the 7th Arc and the Drift debris most likely
source location.
@DennisW:
That is actually what they are doing in Australia. 🙂