Who cares. Disabling VHF and Satcom part of ACARS takes all of 30 seconds from the Comms MGR page. Anyone requiring EE bay access inflight can do so easy enough ATM (however this will change in future)

So the suggestion is that the pilots manually logged on to ATC, let the aircraft broadcast a turn, including their next re-programmed waypoint which apparently they had reprogrammed into the FMC prior to the aircraft broadcasting a pos report, and then successfully made the aircraft disappear?

Do you not think they may have skipped the ADS log-on procedure, if in fact local ATC even HAS ADS, prior to trying to go dark??? For the aircraft to be "Contracted" as you say above, the crew would have had to manually request a log-on. This makes absolutely no sense given what subsequently transpired. What possible reason would they have had to do this? If the reports said they had logged on, broadcast a position report including the next flight-planned waypoint, THEN disabled the ADS and ACARS PRIOR to turning onto a new track then I could sort of understand it....

The arguments on here get less and less logical by the minute...

Yes I had noticed that the last "over" had changed from "All right, roger that" to "all right, goodnight". Could someone have misheard that when it was first reported. Maybe.

The context for this was disabling the CVR and FDR....

Cabin oxygen
 

Oxygen generators or piped...it does not matter really. At that altitude you require a pressurised mask. Those are only available in the cockpit. All irrelevant anyhow as the aircraft would not be able to reach that altitude, not with that load and fuel!

Rigbyrigz: The FMC does not downlink every legs change. I think it is HIGHLY unlikely, as I've posted above, that the aircraft was logged onto Kuala Lumpur ADS (WMFC) at the time the FMC was reprogrammed by whoever was altering the flight route. This is extremely easy to verify.

If it was logged on then it could have conceivably have downlinked the change in next waypoint ONLY, but after flying 777's for 10K hours so far I'm still unsure whether it does this immediately the change is executed in the FMC or at the next waypoint/18 minute reporting interval.

Either way, as stated previously, unless the crew had manually initiated an ADS log-on ATC would be clueless what they had in their FMC.

While there is an MAT (maintenance access terminal) in the cockpit, in order to change the airframe code, there are 2 prerequisites - one, the Air/Ground logic must indicate Ground and two, new ID data is uploaded only via disk file which is created by a GBST software package - something a pilot is not going to have access to - usually the operators are dispatch and maintenance.

The left turn towards P. Lankawi makes sense.
It would imply a fire in the climb taking out the acars with a positive fire warning such as smoke intrusion after the last transmission, followed by turning off all cockpit electronics, hence loss of comms.
There are still problems with it as there are with all other scenarios.

VApilot2004

thanks for that info, it is what I would have expected and like the air/ground bit, so even if you had a MAT in the air bit of a problem, data possibly from a undercarriage weight on limit switch

I don't think FE Hoppy has made any such claim. You may be miss attributing the analysis.

If that suggestion of a fire and no comms is correct, then surely it would have come down in the sea and there would be debris? How long after AF774 went down was there debris. I can't remember. In that case they had a Mayday call though.

OK, jean. OK eliptic.

If captain heads for Langkawi with a catastrophe on his hands, where did it end up? What's your thought on that? Had it landed there, or on that island, a trace would by now probably have been found.

If not, why not?

Second point: if it goes down in the first two hours of flight, signficant amount of fuel on board.

I am not sure how you reached this conclusion but nothing could be further from the truth. In fact substantial analytical work went into the n-version (voting) Ada development, including Z/VDM specifications and absolutely strict and correct interfaces (this was for the 744 and I am sure has been enhanced and developed since).

I spent time working with the 744 FADEC Software so I do know at least a little about what I talk about (as well as having time on the 737 Classic).

To criticize code in the sense of vintage is a complete misnomer. Software tools in the mid 80's were starting to get very serious in terms of system provability and verification, and the Ada compilers were excellent in picking up all sorts of nasty things (static and dynamic). All the development teams were isolated and all produced seriously good provable engineering.

Yes, time has moved on since those early days, but essentially most of the work stands intact as well it should.

Rogue data insertion into the architecture would be completely non-trivial.

Indian radar
 

It's remarkable that India's radar covering the Andaman Islands was turned off at the time MH370 might have flown over because apparently "it was too expensive" too keep it on all the time, although I'm sure they really didn't want to have to reveal that information.

It makes you wonder how many other countries' radar systems are not all they're cracked up to be, which would of course improve the chances of MH370 having successfully flown over other areas.

Can anyone confirm where the search for underwater ELT pings has occurred?

A strong contender is loss of control and nose dive into shallow water with wreckage jn the 20-40 meter thick mud.
Can the ping be received if it is buried in a few meters of mud?

In the loss of control scenarios (bomb, fire, mechanical) and suicide, it is feasible that massive in flight disintegration need not occur and like Egypt air it impacts nose first, leaving very little floating wreckage or fuel slick. Particularly in the marshy areas around Malacca straights.

In respect to the sat pings they are not verifiable, is the transmitter attached to the airframe? Also no way of knowing if the transmissions have been cloned.
In respect to the claim that a unique un-hackable and secure address is attached to the ping I submit the theory the protocols are not battle hardened to withstand a 21st Century hijacking.



Mickjoebill

@RifRaf3, what problems do you identify with it?

I'm also inclined to believe that it was catastrophic failure at approximately 01.21.

The confusing picture built up by Malaysian radar data describing flight to the west would fit the presence of a SIA (or other) 777, although you would expect this to have been thoroughly checked.

At a shallow depth, it fits with the timeline, and fits with the oil rig account.

The problems I see are apparent lack of wreckage, the possibility of tidy ACARS shutdown (still claimed?), and what would seem to be the slim chance of functioning Inmarsat equipment in the sea after the catastrophic destruction of the AC. There's also the question of why such huge efforts have been made pursuing anything but this obvious, Occam's razor scenario.

The missing piece would seem to be the six other satellite pings. If they were all the same range, then I can't see any other possibility.

The Langkawi scenario would imply incapacitation and continued flight either until fuel exhaustion, or a/c breakup, or loss of control. That's wide open as far as search areas are concerned. If cockpit smoke is so severe as to destroy landing capability a a climb into thinner air might be a last ditch attempt to extinguish the smoke.

Mickjoebill:

If it's underwater, and if the nose hits first, I'd expect the tail not to be buried. IIRC, tail is where FDR and CVR are mounted. (If wrong on location, apologies). By the time the wreckage hits the bottom, acceleration in the "down" direction would be pretty small. Granted, once in a bit of mud, sound of acoustic beacon pings would be muffled, no idea as to the dB loss.

How deep is the water in your consideration of "shallow water." (Muddy bottom granted in the area I think you are talking about).

Dozens of pages ago, a very succinct explanation was provided of how an aircraft at those speeds find hitting water a lot like hitting land, in terms of the decel at impact on the water's surface. FWIW.

Not with a standard walkaround bottle and mask, even at high rate.

In a cabin above 40,000', surviving beyond a few seconds is a full time business involving pressure breathing and a real oxygen mask (like a fighter pilot would wear) with pressure breathing capability that pins the mask so tightly to the face with an overcentre lever, it's almost painful. If you're not familiar with the term 'pressure breathing', look it up; it's possibly on Wiki.

It would also, very quickly, become unbelievably cold. And I mean COLD, to the point of incapacitation.

More Data Please
 

1. Distance readouts and times from all Inmarsat pings
2. 3D Primary radar position readouts and times from at least Malaysia and hopefully Thailand, Indonesia, Burma, China and India if willing to share.

At a minimum the Malaysia primary radar positions would yield airspeeds, altitudes and last heading. Until I see radar echoes at the zigzagging waypoints, I'll remain skeptical about the announced course.

We can then apply DR or a compass to plot possible positions on the various ping arcs. It may even be possible to eliminate one of the 8:11 arcs -- or perhaps shorten them.

North arc possibilities include: CFIT, hard landing, clandestine landing perhaps with a serious quantity of tarps or paint or sand to cover up. Planes trying to stay below radar in the dark in the Himalayas or Pamirs have a good chance of hitting one of them.

South arc: ditch in open ocean or bay of a French rocky island or hard landing -- or plunge into ocean.

I suspect spysats have already had a careful look over the TAAF, terres australes et antarctiques francaises.

How many months would it take for cushions, baggage etc. to drift to the Patagonian fiords? How long would it take for somebody to spot any of it there?