Last month Robyn Ironside, the National Aviation Writer at the News Corp Australia Network, published what struck me as an extremely important article in the Daily Telegraph about the work of scientist Patrick De Deckker, who had obtained a sample of a Lepas anatifera barnacle from the French judicial authorities and conducted an analysis to determine the temperature of the water in which the barnacle grew. A snippet:
The same 2.5 centimetre barnacle was used by both French and Australian examiners — but different techniques applied. “For my analysis, I used a laser to create little holes of 20 microns, over the length of the barnacles. In all we did 1500 analyses,” said Professor De Deckker.
Intrigued, I reached out to Ironside, asking if she could tell me more about De Deckker’s work. She very graciously did just that, and shared this extremely interesting nugget, a verbatim quote from De Deckker:
The start of the growth was around 24 degrees (Celsius) and then for quite some time, it ranged between 20 and 18 degrees (Celsius). And then it went up again to around 25 degrees.
This is surprising. The graphic above shows the water temperature in July 2005, which I take to be a rough proxy for the water temperature in March 2014. (I would be extremely grateful if someone could extract granular sea-surface temperature maps for March 2014 to July 2015 from NASA or NOAA databases available online.) It shows that the waters in the seabed search area are about 12-14 degrees Celsius. To find 24 degree water would mean trekking 1000 miles north, above the Tropic of Capricorn.
It has long been known that Lepas anatifera do not grow in waters below about 18 degrees Celsius, and that in order to begin colonizing the flaperon (if it began its journey in the search zone) would have had to first drift northwards and wait for warmer months and warmer latitudes. What’s peculiar is that this particular Lepas would have to have waited a good while beyond that, until the flaperon arrived in water six degrees above its minimum. As I’ve written before, Lepas naupali are common in the open sea and in general are eager colonizers of whatever they can glue their heads to.
Peculiarity number two is that after this period of initial growth the flaperon then found its way into significantly colder water, where most of its total growth took place. What’s weird is that every drift model I’ve ever seen shows currents going through warm water before arriving at Réunion. Where the heck could it have gone to find 18-20 degree water? And how did it then get back to the 25 degree waters of Réunion Island, where it finished its growth?
I’m frankly baffled, and am appealing to readers to ponder historical surface temperature data and drift models to help figure out what kind of journey this plucky Lepas might have found itself on.
@Ventus45
I think Malaysia Airlines burned their maintenance records purely as a precaution. A very sensible thing to do in the circumstances (from their point of view, of course) Any dodgey , third world airline would do the same. EgyptAir are probably arranging something similar, even as we speak, if they haven’t already done so.
@Johan
Re: “Sully”/Eastwood
You are making it way to complex. Eastwood comes from my era not your era. We (Eastwood and I) could care less about messaging or establishing moral boundaries or the role of government in our lives. The only thing we care about is how to “get the dogs to eat the dog food”. Dog food in this context refers to whatever it is we are selling – does not matter if it is a movie or a smart phone. Eastwood’s track record in this regard is excellent. I don’t really know what he thinks about anything.
One more observation about the burn marks: local scrap dealers may tell beachcombers to burn any plastic/organic material to get pure metal. This seems to be pretty routine for 3rd world recyclers of 1st products. Blaine says that lack of scorching on edges makes this unlikely, but it’d be good to have a forensics specialist look at the burn patterns.
@ikr
I’d bet my bottom dollar that burning was done on the beach. If a piece of internal partition turns up with burn marks on it, I will be happy to reconsider, but I think I’m safe.
It seems odd that Blaine is giving any interpretation to the debris at all, even suggesting that it is from MH370 is potentially a stretch, not to mention further suggesting what part of the aircraft the debris may have come from, and how and when it came to be burned.
Either Blaine is starting to have strong opinions about accident causes, which may be understandable, or it would seem other experts may have preliminarily confirmed the debris for him.
The other possible outcome or motive is that, by rushing to a “fire on-board” conclusion, it potentially forces those who may have secret evidence to the contrary to show their data, which seems to be happening all the time in this case.
The rush to judgement may also show frustration with the lack of attention that Malaysia is giving to the debris findings, which in and of itself seems to counter-indicate the fire on-board scenario as the root cause.
S25 files
https://www.mediafire.com/folder/w5h5xpz6rt5e8/S25
OK, I see what you’ve theorized – a ~35 minute holding (racetrack)
pattern between MEMAK & BEDAX.
DrB is considering recalculating, using as an included parameter
the additional fuel usage caused by a running APU.
@S25 , although your theory requires a piloted flight (and therefore
it is more difficult to understand why an APU would be running), if
you did have the APU running, would that enable you to discard the
holding pattern?
Cheers
@susie @all
Dont worri about my attention, Susie, i am following this blog every single day, but i am not an engineer and cannot contribute to the excellent discussion here.
My background is more like philosophy of science, and therefore i lean to the methods of Brock rather than trying speculation about evidence.
I am not married to a specific scenario, but i am married to common sense. I think in this wonderful blog there is a lot of anarchy embedded, which allows for excellency, but also allows for Trolls and the like. Hope the excelency wil prevail.
But by watching this blog develop from my point “on the roof” i think we should return to some very simple questions, which cannot be answered easily:
The most important question, that was not asked here all the time, imho would be
Do we analyze only one event (disappearance at IGARI)?
or
Do we analyze two events (“IGARI” and “SAT-miracle/FMT”)?
The answer to this would make a lot of a difference.
@DennisW:
I actually was about to write precisely that — in a contrasting comparison to Heston that sounded good until I tried to get it on “paper”. “Clintan”, as he is known to everyone here (i.e. the Clint), is selling, of course, and working on his brand uninterruptedly. He couldn’t have wondered off too far from his niche in his public life — to remain credible. And credibility is what Heston lost, wasn’t it? If he ever had one (I know way to little about Heston). A sellout.
And don’t overestimate your age. And don’t underestimate Clintan’s worldwide impact. The American dream is not foreign to anyone. We made you. You are made of us. (But don’t let it go to your head.)
@S25
Just a quick look at your 19:41 numbers. I always start there because the physics are somewhat simplified by a virtually stationary satellite.
Your ground speed of 467 knots results in a BFO that is off by about -5Hz. Your calculated total value of 108Hz is only -3Hz relative to the measured value of 111Hz. However, you are using a bias of 152.5Hz which is 2Hz higher than the 150.6Hz most people have calculated. That leads to -3Hz error versus the -5Hz I would claim it to be. Not that I think 5Hz of BFO error is unreasonable. That is the value the DSTG uses for a standard deviation.
The DSTG shows a “most probable” speed of 410knots at 19:41 which agrees virtually exactly with the number I calculated some time ago.
See end of link below:
http://tmex1.blogspot.com/2015/09/mid-flight-speed-mh370-mid-flight-speed.html
@ROB @Ikr
Anyway before jumping to conclusions those pieces have to be investigated thoroughly.
Blaine Gibson presents himself, for understandable but one-sided reasons IMO, a complete opposer to anything that can point to Zaharie as the master-mind and culprit.
This two pieces would serve his presumptions very well.
Although he deserves a lot of credit for his efforts he should understand he is watched critically as well.
Afterall he is also a lawyer and therefore knows how to play his cards in matters like this.
At least Zaharie’s family and probably some others would be willing to spent a fortune on someone how would be able to prove Zaharie is not to blaim.
When he reads this he may be very offended. That’s not my intention. I hope he understands.
@Victor: I’ve taken a further look at your latest path proposal. It seems to require not only a deep incursion into Indian airspace, but some 35 minutes spent circling one of its airports (VOCX). With, if the ISAT data is to be trusted, the SDU back up and running the whole time.
If the SDU was running: does it not follow that MH370 would be back up on civilian radar screens, if in range?
If all of the above is true: how do we reconcile non-detection – even after poring over recorded data, after the fact – by the Indian CAA?
I’m honestly trying to figure out how you square this circle. Apologies if this is asked and answered.
The article I’m referring to explains the co pilots cell phone connecting to a tower, which I know has been talked about many times. But there is also this, from the Daily Mail,
An email received by the Mail recently suggested that the aircraft had been hijacked and that the pilots had been ordered to fly around Malaysian and Indonesian air space while negotiations were carried out.
Those negotiations, said the email – from a source in Malaysia which could not be verified – demanded the dropping of a jail sentence imposed on Malaysian opposition leader Anwar Ibrahim.
The hijackers, said the email, gave government negotiators five hours to meet their demands or the plane would be destroyed.
Last night Malaysia’s Acting Transport Minister said he could not comment on the report in the New Straits Times adding that ‘if it is true, we would have known about it much earlier.’
Mr Hishammuddin Hussein made his remarks to the Malaysian news agency, Bernama, pointing out that he had adopted the approach not to confirm anything without any corroboration or verification from the time when the aircraft was reported missing.
This was new to me..
Wrt motive, as a couple things have come to light let’s say there was a hijacking that placed ZS under duress but that hijacking failed after the last check point but the crew were able regain control after mh370 was heading south but it was still in time to land near northern Australia. After all his retirement destination was Australia. It serves the purpose to have alll keep quiet and why Malaysia govt to keep being uninterested.
@S25
Nicely done, IMO. Thank you for sharing. Thanks also to Ventus for providing access links and uploading.
@S25
I went to bed at 3am after uploading your files.
I have just got up and checked the download stats for the six files in the seven and a half hours so far.
Downloads File
Twenty Large Yellow-461
Seven Yap-461 spreadsheet
Six Yap-467 spreadsheet
Thirteen Travel Time
Fourteen Samples
Seventeen Yap-Comparisons
@buyerninety,
The APU fuel flow is ~ 1 kg/minute when loaded. If it ran from 17:30 to 00:19, that is an interval of 409 minutes, and it would consume 409 kg. This amount of fuel is 0.93% of the fuel load at 17:07, and the calculated PDA for the engines would be reduced by this amount. For my candidate True Heading route, the engine PDA would drop from 4.7% to 3.8%. That moves it into the acceptable range for used engines.
In Holding LRC with a racetrack pattern at FL360, the fuel flow at 19:00 would be about 6,700 kg/hr, so the same 409 kg would be consumed by the engines in about 3.7 minutes.
@DrBobbyUlich. The APU fuel flow you quote is net, that for engines out, aircraft descending or slowing. This does not include intake drag , which affects engine power and will increase gross fuel consumption due to APU running.
https://www.dropbox.com/s/mw50xpqhb2p6xyn/APU%20Fuel%20Consumption.pdf?dl=0
A second consideration we discussed a while back; the explanation for the 7th arc log on other than the supposed APU start then.
@David,
@buyerninety,
The table kindly provided by David indicates about 180 kg/hr at FL350, or about 3 kg/min when the effect of the APU inlet drag is included in the main engine fuel flows. In this case the maximum impact of the APU would be about 2.8% of the available fuel, assuming the APU ran from 17:30 to 00:19. That would reduce the engine PDA from 4.8% to 2.0%.
If the APU were started at 18:24, the net effect would be about a 2.4% reduction in fuel and PDA.
I recall the discussion about the SDU reboot at 00:17:29, but my questions about alternate SDU power sources were never answered, so I don’t know if an alternate scenario (to APU start-up) is a realistic possibility. Perhaps you can describe possible alternate scenarios.
@Johan
I don’t really have a problem with Heston. Not sure I would characterize him as a “sell out”. Just a man who changed his mind or a consistent man who changed his allegiance as the group he was allied to changed.
No matter. “Sully” is great, and I will definitely see it. I want to be entertained. I don’t really care if the NTSB is misrepresented. Nor does anyone else except the NTSB who will all buy a ticket anyway.
@Johan,
“the angle would not be political, not primarily, but personal”.
The personal aspect of it is evident in more ways than one, I see that also. Perhaps sparked by intense anger, hopelessness or, as you rightly put it, utter disgrace. Most people don’t let on what they are feeling or planning. Z would surely have kept his plans close to his chest so he could carry out the act.
MAS was ailing well before March 2014. The company suffered losses of up to $1.7B since 2011 due to, amongst other reasons, poor management. Like with any company that needs a serious financial overhaul, we can only imagine the “coffee machine gossip”. Cutbacks, lay-offs, relinquishing entitlements etc. would have been predictable and inevitable. Retiring the entire 777-200 fleet may have been in the works prior to March 8, 2014 and would have had a profound effect on Z.
Anyhow, enough speculation on my part …..back to facts!
@RetiredRF4, Brian Armstrong. I have been in contact with AMSA about the cabin ELT and its effectiveness.
Summary, as best I remember it:
It will transmit 50 secs after activation and will need to have line of sight through a window to a satellite, that is it transmits at the same power (5W) as an EPIRB, whose signal I was told could not be expected to penetrate the hull without excess attenuation.
An initial successful transmission will contain sufficient information to be able to alert the originating country and also that with SAR responsibility as to the emergency. This may be followed by GPS position information from the geo-stationary satellite, though the position information from a moving aircraft may be relayed as ‘scattered’. This may take some minutes of ELT transmission.
I was told that position info from the low earth satellite, which interprets Doppler, would be problematic; as expected. I did not get a clear answer on whether there was a risk the received signal from a fast moving aircraft would be outside reception bandwidth, akin to SDU frequency correction for aircraft created horizontal Doppler.
The above applies to the more-likely-successful transmission of the installed ELT if activated in flight (other than attenuation of course).
About whether cabin crew would be trained to activate the cabin beacon my informant referred me to the airline, as expected. I much doubt that information would be released to the public but the Flight Attendant Union’s question surely would be in light of the transmission process taking time and transmission needing to be line of sight (which would take luck) that taking time with the antenna at a window. With other things going on I do doubt the cabin crew would focus on this even if trained.
What would be the purpose? It could bring no help midair and in the event of a survivable ditching they could activate the ELT at that point to supplement that installed. After an illicit landing where there was no mobile coverage I suppose it could have a use, but a long shot.
And also cockpit crew would be aware of cabin crew’s training and capacities in these eventualities…
I was told that most commonly an emergency signal is not received because no-one got to the transmitter, which tends to sideline signal attenuation. My informant could not speak about MH370 and perhaps I read too much into what that remark implied.
There for my part I leave it.
@DrBobbyUlich. I did not have an answer then as to pilotless 7th arc log on alternatives. I have raised whether the APU sequence is sound through (my assessment)lack of fuel for it to run for long enough or even at all. However that does not help with the alternative, the most obvious being a pilot present and switching as might have been the 18:25 way (Victorl did offer some off the top of the head alternatives to power restoration then in his May 16th post, 9:06 AM though most centred on spoofing).
I have no evidence at all supporting a pilot being present at 00:18:30, about the time of SDU power restoration.
Oxy raised the notion of the left engine being isolated electrically such that when the right failed the APU would auto-start, the left continuing; but that would yield the same explanation as that current.
Others have raised SDU reboot possibilities from other than power supply restoration and they may be able to help but other than that, sorry, it seems to be a stopper as it did earlier.
Further about the drop box figures, these are from the manual but why they are so aircraft weight dependent is unclear.
@David Re ELT
You either asked the wrong question or you generalized your question. The problems you mention (time delay, sat connection) are known and had been discussed.
The beacon function of the ELTA ELT can transmit besides the 406 Sat frequency on 243.0 and on 121.5, and that’s a frequency which is monitored by ground, sea and air stations. From IGARI to FMT such a operating beacon from MH370 could have been received by several hundreds receivers.
The question, in what regard it could be helpful is a biased question. Flying around without any kind of conmmunication far away from your planned route it is vital to communicate the distress situation If the ELT is the last possible means of communication than any crew would think about it.
Take it or leave it, there is a great probability that the ELT’s were not used by intent, neither the installed one, which could have been activated from the cockpit nor the portable one available in the cabin.
That imho puts the technical failure scenarios at rest and bad intent on the top of the list.
@Brock
“If the SDU was running: does it not follow that MH370 would be back up on civilian radar screens, if in range?
If all of the above is true: how do we reconcile non-detection – even after poring over recorded data, after the fact – by the Indian CAA?”
Detection on Secondary radar is dependent on an operating transponder system. It has nothing to do with the SDU.
@DennisW and @Johan
I hope my comments about Sully are not misconstrued. Sully is a great movie, taut, coherent and precise storytelling at its best, period. And Eastwood is undoubtedly a great director, period.
When I mentioned the NTSB in there, it was more to comment on the mischaracterization for the sake of a storyline. The NTSB are indignant
http://m.csmonitor.com/The-Culture/Movies/2016/0909/Why-complaints-of-Hollywood-inaccuracies-are-unlikely-to-spoil-Sully
http://www.usnews.com/news/politics/articles/2016-09-08/real-life-investigators-object-to-portrayal-in-sully-movie
But that misgiving doesn’t detract anything from the movie in my view. Additionally the NTSB cannot have it both ways:
http://www.cbsnews.com/news/ntsb-sully-could-have-made-it-back-to-laguardia/
For Eastwood can justifiably quote the CBS report as the basis for his narrative. And so I can see where he is coming from.
Enjoy the movie for what it is. It may not make it to the pantheon of the timeless classics but it’s a great movie nonetheless.
Captain Phillips was riddled with inaccuracies but it was a great movie nonetheless so it’s not like Sully is breaking new ground in that regard.
@kegffertje
Thanks for the response and astute observations about that interview with the mystery woman. My sentiments exactly. Additionally non activation of ELT during dash across Malaysia further pushes mechanical or fire emergency plus ghost flight post FMT to the back burner. Only sticking point would be the final outcome. I rather think he just let it drop or he tried to imitate sully for the kicks but it went awry and ended right there the way it did. Fugro probably missed it in their scans.
@RetiredF4:
You do seem to have a point there.
Lack of signal from the cockpit ELT is perhaps easier to explain than the one from the portable ELT in the cabin.
@Keffertje:
Yes, so there is a very fat chance that somebody knows something. And if there were cutbacks, pilots with wrong political opinon (and spine issues) might have to go first.
@DennisW:
Forgive me about Heston. It was forced. Heston was treated somewhat onesidedly in Sweden (via the evening news) his last decades. U.S. gun laws rarely meet understanding among serious people here, since it has little or no political significance here. And we have tax financed medical care since ages, too. And few pharmaceutical giants. We don’t like killing sprees and mass shootings by tradition (it is inconvenient), and people here tend to believe that people raised with guns (without the right reasons for it) will tend to resort to guns for problem solving (in their minds, long before they pull it off the wall). But we are ten million subarctics, so most comparisons fall to the ground. Everyone is supposed to be “your neighbour”, so adequate, proper gun use comes with the territory. We take it out in American movies.
&@Wazir: I need to see it, eventually. Captain Phillips was on tv yesterday, and Hanks was really good there. But I know the qualities of all the involved, save perhaps NSTB. Screwing around with the truth is what fiction is about. Without exception. Heck, documentaries is about screwing around with the truth. The director has his/her responsibility towards the audience first. They will judge the artefact as it appears to them, independently of the truth (or nearly). And if the movie was a piece of news, it would risk oblivion.
I think we might be weighing down on people’s patience with this side-track.
Is it mandatory for cabin crew to inspect the portable ELT during pre-flight check?
Maybe this has already been covered, but I’m not aware of this.
@RetiredF4: thanks for clarifying.
So, even assuming it is easy to turn both off at IGARI, yet only the one back on at 18:25 (something I neither concede nor dispute), this proposed path still only works if the PIC wishes to be tracked by satellite and primary radar, but not by secondary radar. (Circling a military airport for 35 minutes does not seem to indicate a desire to evade primary radar. And it took me 10 minutes online to find very public discussions of plans for BTO tracking in the wake of the Air France disaster; it seems reasonable to suppose anyone contemplating the actions implied by this path would have known about it.)
I know this isn’t your path proposal. Just trying to sort out its internal logic.
@David @RetiredF4
Information on the following link says the ELT is switch-on automatically by a 4.5feet/sec (2.3G) primary G-switch or through manual activation.
http://writersblocktgh.blogspot.nl/2014/03/boeing-777-rescue-and-communications.html
Doesn’t this mean the primary G-switch will activate the ELT anyway, regardless if it was manualy switched on or not, in case of a crash exceeding 2.3G/4.5feet/sec?
Just want to say that I’m a little surprised that the ATSB released five photographs of the Pemba flaperon (http://www.atsb.gov.au/publications/investigation_reports/2014/aair/ae-2014-054/) and three of them were essentially the same shot. The fourth is of a corner that’s visible in the first three, and the fifth is a closeup of the ID plate. So these shots do a poor job of giving us a comprehensive sense of what the thing looks like overall.
Definitely looks like no barnacles.
@GeRijn:
Like to know about that too. Or it was simply just not working?
@Ge Rijn
The normal switch position of the installed ELT during flight is armed, the portable ones is off.
In the armed position the ELT will go active like you state, but the reliance is disputable. The first signal is sent about 50 sec. after activation, and in the meantime the crash might have severed the antenna
cable, damaged the ELT or it might be below enough water to prevent the signal from reaching the sat. Therefore the non activation during the crash is no pointer at all, while the non activation during a possible severe emergency without other means of communication like we discuss in the MH370 case especially prior FMT should tell us something.
@Brock
…….if the PIC wishes to be tracked by satellite and primary radar, but not by secondary radar. (Circling a military airport for 35 minutes does not seem to indicate a desire to evade primary radar.”
I’m the wrong person to ask that question, as I do not believe that the person in charge at that time had any intent to do so, more the opposite. All points to the intention to stay dark with all means. The SDU relogon might have reasons we are still unaware of.
When I interpret the supposed holding correct, it is more a time referenced behaviour than a geographical maneuver referenced one for the purpose of delaying the FMT. MH370 left the area to the south after staying 35 min (holding) in the area for unknown reason. In that timeframe a lot of things could happen, from holding like you assume up to landing and taking off again. I’m not aware of any well sourced information that there was a primary radar contact in that area at the supposed time at all.
@re ELT awareness of crew and cabin crew
The most known and most trained systems on an aircraft are the ones needed in case of emergency. There might be a person on the crew who has a bad day and would not remember in a stressfull situation, but not a complete crew.
@Gysbreght. Yes well I think the Exner simulator run and those implicit in the ATSB published stance indicate the phugoid would be convergent in those conditions though high AoA, speed, g, ground effect and bank might influence that in other flight conditions.
Distantly relevant, I have experienced divergent pitching in a glider on landing. In that instance the pilot (me) fed into an initiating phugoid of human response frequency, me out of phase. I escaped it only by letting the stick go momentarily– a distant cousin of stick fixed vs free. The aircraft was crashed by another in an identical gyration a month or so later. No sign of anything like that in any other phase of flight in that aircraft.
I doubt the simulator would be set to stick free since not having a pilot would be beyond its scope. It may well be too that the difference does not amount to much if anything.
About all this I declare an attachment (probably temporary) to a supposition that the rear parts of flaperons and flaps (at least) came off due to overload in the spiral and the front sections separated due to shock as in the MH 17 case, in my opinion. In that instance the flap rear did not separate since I doubt the surfaces were as severely loaded as in a tight spiral.
Hence I seek ways in which your model might be converted to support that inclination; in other words to come towards the Boeing/ATSB BFOs, in their more recent stance.
Not that you will relish that.
Could be:
• Pitch increased quickly and markedly at the top of a divergent phugoid, contrary to what the simulators indicate, starting just before the 00:19:29 5000 fpm BFO?
• Roll increased due to yaw trim say? Probably nothing to do with it but the FI Appendix 1.6A indicates the rudder trim indicator was replaced on 4th March, 2014. (Of general interest, attention to a hole at six o’clock in the right engine acoustic panel was deferred, on 5th March and there was an APU flight start test on 3rd March, not that either need prove to be other than routine).
• A side effect might be an even tighter spiral?
Going on, you mention under 5, “commensurate with pitch compensation for bank angle”. Can you expand on this?
On the Hudson landing, “The ATSB investigated the effect that mode may have had on the airplane’s inability to flare before touch-down”. Unintended consequences. Interesting.
I prefer the term ‘restoring’ AoA to ‘stabilising’ it since dCm/dAoA I think would be –ve still.
I welcome the opportunity to put some remnants from 50 years ago to some use in such discussion thanks.
@retiredRF4. “It would be interesting to achieve agreement, at what time the flight control mode would have changed from normal to secondary and then to direct”. Yes, not there yet re normal to secondary. (I do not think it would revert to direct). It does depend on this bank protection and any other flight envelope protection such as speed and I am unsure that we will get the manuals to match the practice with the information to hand. However it is possible that the simulator in applying bank protection in the Exner run is in error in a very non-normal circumstance.
RetiredF4. Sorry to have put you in reconnaissance
@keffertje
Here is why I view the contents of that interview with the mystery woman significant. In isolation, a report like this one I am linking below would reek of pulp fiction as would that interview:
http://www.smh.com.au/world/missing-malaysia-airlines-pilot-terribly-upset-by-marriage-breakup-20140326-zqn4p.html
But taken together they become complementarily significant and when portable ELT is left inactivated despite ample time do so and the manner of the flight post IGARI appears suspicious, one can link these seemingly disparate jigsaws into a cogent whole.
It’s tough assigning blame on human factor but the circumstantial evidence is compelling. I seriously doubt it was political though simply because any such act would have been fully exploited to destroy the opposition once and for all.
@RetiredF4:
So either the crew was mislead about the reason for the turning back or incapacitated, or the ELT was hid/broken/destroyed/locked in the cockpit with the pilot?
@Gysbreght. For phugoid in my glider experience please read Short Period Pitching Oscillation
@Johan
“So either the crew was mislead about the reason for the turning back or incapacitated, or the ELT was hid/broken/destroyed/locked in the cockpit with the pilot?”
You may take your choice.
One caution though: To mislead a cabin crew is not that easy anymore since 911, and same goes with the passengers. One suspicious person would be enough to spread the word around.
What happened to the passengers has been the discussed but evaded question from the beginning. But as it will not lead to the aircrafts final resting place, this questions may remain unanswered now. Concerning possible and probable cause of the disappearance the obvious inactivity from the aircraft occupants, and that includes all soals on board, has to be brought into the equation.
@RetiredF4 @David
Then there would be also the possibility the ELT’s did not activate because impact speed/ forces did not exceed 4.5feet/sec 2.3G I suppose?
@RetiredF4
We disagree on the flight crew and ELT use issue.
First, the flight crew had no reason to believe the location of the aircraft was not known. If I was on a hijacked aircraft it would not occur to me that in this day and age the location of the aircraft was not being actively tracked.
Secondly, the flight crew would not be trained to use the ELT as an emergency locator in the event of a hijacking. That would be an extraordinarily improbable event, and outside the use profile of the ELT. I can see training for the ELT’s intended usage which is not for communicating aircraft location while in flight.
In times of stress you fall back on your training,
What you describe is APC (Aircraft-Pilot Coupling), formerly referred to as PIO (Pilot-Induced Oscillation. That has nothing to do with phugoid motion. A phugoid, also called long-period oscillation, is by definition constant AoA, resulting from positive static longitudinal stability, without pilot input. The phugoid period is π*√2*V/g, i.e. 80 seconds at 347 kt TAS (200 kt CAS; FL350).
At 200 kt CAS, FL 350, 174,000 kg in un-accelerated flight, the lift coefficient is cL=0.658.
Pitch compensation for 30° bank increases that to cL=0.760. The trajectory of the simulation (nz and turn rate) requires a lift coefficient of cL=0.809 (+6.5%) in the first 3.5 minutes.
@DennisW, @Retired4:
Hm, hijack vs. extended suicide. Makes some sense. Would the captain have time to incapacitate everyone before Igari? Would a hijacker be able to time his actions in accordance with what we know, i.e. entering cockpit well before handoff? (Would Z be able to pretend they were being hijacked and that negotiations were taking place? — that one won’t be popular here).
Was it possible to use the phones (with regard to height or the aircraft’s communications system)? When did passenger’s phone activities end? Irrespective of scenario, the passengers would be on their phones immediately if a hijack with less than a kalashnikov up their noses. An update please.
FWIW, per Wikipedia, “The signals are monitored worldwide and the location of the distress is detected by non-geostationary satellites doppler trilateration and in more recent EPIRBs also by GPS.”
It goes on to say that it can take up to TWO hours for a satellite to pick up a signal (average is 46 min.). Therefore, even if the ELT’s were activated upon impact, there is the possibility they could have sunk by the time the satellite was close enough to detect the signal.
If the IFE was activated circa 18:28, does that mean the PAX would have had access to e-mail and text messages?
Also, if only the FO’s cell phone connected to a tower near Penang doesn’t that mean EVERY single passenger had shut off their cell phone (or put them in airplane mode)?
@LaurenH, I don’t know of any air crashes at sea where the ELT was activated. I’m not saying there weren’t any, I just don’t know of them.