Two weeks ago, I wrote a couple of posts about the strange reboot of MH370’s satcom system that occurred shortly after the plane disappeared from primary radar, and asked if anyone could come up with a reasonable explanation. I drew attention in particular to the left AC bus, which the satcom equipment is connected to. This bus can be electrically isolated using controls located in the cockpit, and this appears to be the only way to recycle the satcom without leaving the flight deck. I suggested that there might be some other piece of equipment that the perpetrator wanted to turn off and on again by using the left AC bus, thereby causing the satcom to be recycled as an unintended side effect.
The readers rose to the occasion. Gysbreght pointed out that paragraph 1.11.2 of Factual Information states that “The SSCVR [Solid State Cockpit Voice Recorder] operates any time power is available on the Left AC transfer bus. This bus is not powered from batteries or the Ram Air Turbine (RAT).”
This is an incredibly interesting observation. Reader Oz fleshed out Gysbreght’s insight, writing to me via email:
We could isolate the Left Main AC by selecting the generator control switch to OFF and the Bus Tie switches to OFF; SATCOM is now dead. What else happens……….the Backup generator kicks in automatically to supply the Left Transfer bus. Here’s what’s so spine chilling; if you now simply reach up and select the Backup Generator switch to OFF………..you now lose Left transfer as well. The CVR is gone! I couldn’t believe how easy the CVR was to isolate!
To recap;
Left Gen Control to OFF
Bus Ties to OFF (Isolate)
Left Backup Gen to OFF.
I now firmly believe your mystery reboot was Left AC power being switched back ON……….. after something that had occurred that the perp or perps didn’t want any possible evidence of on the CVR……whatever was being hidden was done by around 1822; AC back to normal.
Gysbreght notes that the Factual Information also identifies the location of the CVR as Electronic Equipment Rack, E7, in the aft cabin above the ceiling, and suggests: “Later [the perp] could have opened Electronic Equipment Rack E7, physically pulled the SSCVR power supply plug from its socket, and then gone back to the MEC to restore power to the Left AC bus.”
Oz has his own theory: “If you are thinking why the hell you would turn Left AC/Left transfer back on? Flight deck temperature control comes from these…”
There’s a precedent for a suicidal airline pilot depowering the black boxes before flying a plane into the ocean: the pilot of Silkair Flight 185 appears to have done just that before pointing the nose down and crashing in December, 1997. It’s easy to imagine Zaharie reading the accident reports and realizing he should also figure out a way to disable the CVR before implementing his suicide plan. When the moment came, near IGARI, one can imagine the veteran 777 pilot suddenly flipping various switches while the baffled newbie, Fariq, looked on.
It’s certainly an intriguing scenario, but it is not without its flaws. As Gysbreght notes, “I would expect the Captain to know that the CVR only retains the last two hours and overwrites older recordings.” So if Zaharie planned to commit suicide by flying the plane for hours into the remotest reaches of the southern ocean, he wouldn’t have needed to turn the CVR off: the portion between 17:07 and 18:25 would have been erased anyway. This is not in insurmountable problem, however. Maybe he orginally intended to crash right away, a la Silkair, but then lost his nerve.
I’m not quite ready to declare, as Gysbreght has, “Case closed,” but I have to admit that the CVR idea is fascinating. Great work, Gysbreght and Oz!
Certain systems were obviously not “perfectly functioning”. The FDR will tell us which systems were not functioning perfectly and probably also why they were not functioning.
@Gysbreght, don’t twist my words. I didn’t say, that the story must be true because Miles O’Brien confirmed it. Bit he did confirm that he has more than one source. And that I believe. That leaves us with two scenarios. Either it’s true and those simulations exist and got suppressed for whatever reasons – or he has been told blatant lies. And we have to ask ourselves: why?
U haven’t made up my mind one way or another. But both scenarios aren’t exactly confidence inspiring.
@littlefoot:
“And we have to ask ourselves: why?”
Perhaps we also have to ask: what was the source of the sources?
@Victor,
I just wanted to thank you for taking the time to re-scrutinize the available radar data. Apologies for the small Twitter barrage, I didn’t want to exclude KP from the conversation. Needless to say, I look forward to the paper in hopes that it can help put to rest another nagging aspect of this tragedy.
@dennisw
The FDR will clearly indicate if the plane was under control at the last hours,minutes. (I think everyone wants to know that)
The FDR records all stuff done manually.
@Gysbreght
“Certain systems were obviously not “perfectly functioning”. The FDR will tell us which systems were not functioning perfectly and probably also why they were not functioning.”
Really? How do you that? Why would you even think that?
@Flitzer
when you turn SE after entering IO the only two airports (suitable for 777) are Cocos and Christmas island
“far” could be just overexaggeration from the journalist
@Flitzer
While I am encouraged by your suggestion relative to causality, the events leading up to your expiration of the pilots scenario simply does not fit well with the observables.
First, there was no attempt to communicate an onboard problem of any kind. The flight path from Igari to the Penang region and beyond does not suggest a flight crew struggling “to get things under control”. There should have been multiple ways and multiple opportunities to communicate an emergency. What the path does suggest is someone flying the plane in a very deliberate and controlled manner.
Secondly, it is hard to conceive of a problem severe enough to incapacitate the flight crew while benign enough to allow the plane to continue for several more hours.
Why don’t we return to this discussion when the flaperon analysis is complete. If the forensics show damage consistent with a high speed dive at the end of the flight, it would support your zombie hypothesis. If it shows the flight basically ended in a controlled ditch it might be time for the IG and ATSB to return to the drawing board.
“If it shows the flight basically ended in a controlled ditch it might be time for the IG and ATSB to return to the drawing board.”
I’d like them to do so in that case but not fancying the chances.
Jeff,
I think you are right as far as Malaysia’s handling of the case, bumbling and incompetent yes, that nefarious maybe not. Let’s see what Miles comes up with regarding the simulator. And I don’t get why they would conceal this information as Zaharie would be their ticket out, wouldn’t they be quick to divulge it clearing themselves, MAS, and all the mfgrs.?
@Cheryl
Some food for thought.
Would it be nefarious in your opinion if ‘they’ (Hishammuddin) knew that it was Zaharie and Mh370 either before IGARI or hours after?
What do you believe will happen (domestically) when/IF they officially accuse Zaharie? Do you think China et al will find this acceptable after 17 months?
I think I know. It will be the end of UMNO/BN. Accusing him has never been in their best interest. It’s 100% risk and a big fat zero in reward (contrary to what some here seem to believe), and always has been. Such is the political climate there.
The fallacy that they would have benefited by pointing the finger at him initially (with OR without conclusive proof) is just that, a fallacy.
Let’s also remember that they did NOTHING to prevent the loss of life of 238 people, and that these people literally VANISHED after flying over, through and around the country.
Unacceptable.
Spencer,
Yes, it would be nefarious then if that was the case that they knew during the traversing it was Zaharie making a protest and have held it to the vest this long from the families. That is a big IF though.
Agreed, it is unacceptable in the Age of Technology that they have lost an aircraft. They “let it slide” right through their hands in the middle of the night either by being asleep at the switch or by not being proactive or not reactive quick enough, or by knowing what was happening as you say and letting it go.
What do you make of the SIO route on the simulator thing? Long range planning? It was too precision-like to be concocted hours after the court hearing?
Not sure about blaming him not being in their best interests though? Littlefoot weigh in here please……………….
@Cheryl
I just want say, FWIW, I that truly appreciate the open-mindedness. As you know, I had you pegged (wrongly) as someone that would defend Z no matter the evidence. I cold not have been more wrong about you.
Look, you know where I stand. If I believed there were any other plausible scenarios that could even in the most tenuous manner be married to overall picture, I would give them consideration. I just don’t see it. I understand that you do, which I can now truly appreciate.
IMHO, the window seal video was made for posterity. I think it was methodically done, in every manner. It portends much, disturbingly.
I believe Z had been sitting on his plan for some time (before window seal, obviously), and that he was waiting to see where the political climate went. But he was prepared to do whatever needed to be done if things failed to change.
IMO the Anwar verdict was HIS breaking point and compelled him to act. It is interesting to note that it set up perfectly for him with Fariq and the evening flight?? This is somewhat curious and another ‘coincidence’? Hmm.
Maybe it wasn’t him, and I truly wish it were not, but it just all adds up to me…and always has.
Of course, I have the resident in-house psychiatrist calling me delusional…
Malaysia must be playing numb and dumb intentionally all the time, otherwise I dont know…
https://www.washingtonpost.com/news/worldviews/wp/2014/05/21/china-malaysia-and-the-weird-world-of-panda-diplomacy/
I put this comment out a week and a half ago and thought I should follow up on it.
“Some food for thought; most commercial aircraft I know of have shear points to let the engines separate to protect the fuel cells (wings) from rupture. Normal terrra firma impact projects them over the wing.
Have a look at the Ethiopian B767 attempting to ditch; does the engine go over or under?”
What I left out was watch the left wing; some of you probably worked that one out anyway. The right engine actually hits a reef; that’s why the wing comes off…..a it like a car hitting a brick wall. Hitting the reef is not a normal terra firma impact.
Back to the left wing which is the interesting one… the high speed ditching one…did it depart over or under?
The answer is………….it remained attached!
Food for thought I think!
OZ
On the rising from the depths theory going around for the flaperon.
If the aircraft sank to any where near the depths currently assumed; the honeycomb would have crushed every cell and every bit of air that would have been present.
That flaperon would have been well truly mangled.
OZ
Left out…………and it wouldn’t have surfaced!
OZ
Why go through the complex process of isolating the left AC bus just to pull the CVR plug ? Why couldn’t they just pull the plug directly ?
I don’t see how an attacker sufficiently knowledgeable to carry out the bus isolation procedure would not have known that pulling the CVR plug was a much easier way to disable it.
@TF, As far as I know isolating the left AC bus is the only way to depower the CVR without leaving the cockpit. If there’s another way I’d love to know it.
Would appear that restoring temperature control is not a valid reason for bringing left bus back on. “Absence” of temp control inputs from flight deck result in temp auto adjusted for 75 degrees F. Can’t imagine pilot intent on doom would care.
https://quizlet.com/20204948/ua-b777-test-questions-air-systems-flash-cards/