Why would you think that? Remote switch installation is mandatory according to U.S. FAA rules (where the plane was built).

The suggestion by James7 that a large jet with underslung engines could ditch in the middle of an ocean, come to rest, and then sink two or three miles to the sea bed, while remaining completely intact, is implausible.

Even if the ditching was flown by a practised pilot, and with all high-lift devices available, it is more than likely that the engines and pylons would be torn off, as well as all or substantial parts of the slats, flaps and elevators. Even if the engines remained attached, the fan cowlings would probably be ripped off. Apart from the engines themselves, most of these large items are made of composite material, and would float.

If the ditching was uncontrolled, it is likely to have been with a clean wing at a minimum of 200 knots, and the wings are unlikely to have been level (even if the surface of the water was). The chances of the a/c landing flat to the water and parallel to the swell are remote, so the a/c would be likely to cartwheel - like the Ethiopian Airlines B767 did many years ago - and break up. In that event, the fin would almost certainly detach and float, as-per AF447, together with an enormous amount of other debris.

The absence of any wreckage recovery is deeply puzzling, IMO. I'm not aware of any major storms in the search area in the interim, but I stand to be corrected. By now the search teams have had plenty of time to estimate the possible effects of current and wind on the movement of different types of weckage.

Bizarre.
 

We have an indicated area to search from the Inmarsat signals. We have, apparently, heard the 'Pings' from the CVR etc...but, as far as I'm aware..there is not one single, confirmed morsel of physical evidence from the aircraft..... Sure, most of it would have sunk.......but SOME items would have floated.....there must have been thousands of buoyant objects in that aircraft. One appreciates the vastness of the ocean......and the wind and currents, - but nonetheless....it does seem very strange. Then again, just about everything about this incident seems unprecedented and bizarre in just about every way...:hmm:

Priceless jewels of wisdom. It would be good to remember these the next time an airliner is depicted flying through solid objects. Thank you. :ok:

Hi,

According to the B777 FCOM emergency section, it does not show a fuselage mounted ELT is attached to the B777 200/200ER.

There are two approved ELT providers for the B-777, Honeywell and ACR, both of which have cockpit control panels and interface with the master caution system. The ELT transmitter, with internal battery, is mounted inside the fuselage skin, above the aft cabin doors and is connected to an external antenna mounted very close above the ELT.

Second item, an earlier (deleted) post mentioned MAS avionics shop. To my knowledge their shop in KL does not have the knowledge, skills or approvals to do any work on the Honeywell AIMS cabinet modules nor the ADIRU.

Third item, The CVR/FDR are mounted in hard trays, attached to major airframe structure in the tail of the aircraft. Not accessible in flight, and not likely to be dislodged from the structure during a crash. Also please remember that there is a QAR module in the avionics package that might be readable when found.

Preliminary Report Release May 1
 

Malaysia's Prime Minister Razak says government will release a preliminary report on MH370's disappearance - @CNN cnn.it/QBIeTs

Can we expect fact to be separated from fiction given its coming from gov?

There are only two possibilities: Those in charge are incompetent fools and completely wrong, or the equipment isn't sensitive enough to find the wreckage.

There isn't going to be an answer in the preliminary report.

Tropical Cyclone Gillian
 

Chris Scott " I'm not aware of any major storms in the search area in the interim, but I stand to be corrected."

While the search was concentrated on the area south-west of Perth, TC Gillian passed through the current search area. Whilst it had weakened from its original Cat 5, it would likely have been generating wind and waves enough to pulverise any larger pieces of wreckage, and widely disperse anything left floating.

If the aircraft was built after 1992, the cockpit remote switch was a requirement of the TSO for ELT installations.

Pingology precedent
 

Have been following the thread with interest from the initial sad loss.

Would I be correct to say that the Inmarsat satellite technology that has lead the search to the Indian Ocean has not previously been used to locate a lost aircraft? Perhaps we would have been more surprised to find it?

It seems to me that while the mathematics etc are very plausible, at the end of the day the technology is unproven to say the least. Maybe its time to start over?

@lulu....
While the application is new, the basics are very old....1842 to be exact :ok:
The doppler effect analysis is all they have to go on ATM....as far as we know ;)

No, but calculated positions from satellite handshakes have been compared with known positions of similar aircraft, and other flights of the same aircraft. So it seems quite accurate.

Besides which, if the sounds heard underwater were the recorder beacons, the satellite handshake data is largely academic at this point. The actual impact location was never known very accurately because there's only circumstantial evidence that the final handshake occurred as the aircraft was crashing... it could have continued flying for up to an hour afterwards.

Pingology
 

Thanks and i get that it should work in principle, and that theres nothing else better. Its just I reckon that as a plane finding technology it would have been too good to be true. I mean the margins for error are just unknowable.

Given that the Nuclear test ban treaty people said that their hydrophones at Cape Leeuwin did not detect MH370 impacting the ocean, it may place more weight on a controlled ditching.
This can detect icebergs falling in Antarctica, so if the plane struck the ocean with high force, it should have being able to detect the acoustic waves.

It is not a new technology, and the next time you go through a police radar trap try and convince them the margin for error is unknowable.
In the end the Satellite track path took searchers to a place where ELT beacons could be heard. That is all that could really be asked of that approach

SATCOM Equipment
 

Rampstriker,


The SATCOM system on this era B777-200ER consists of the following components:

• Satellite data unit
• High speed data unit
• Top mounted high gain antenna
• Beam steering unit
• Low noise amplifier/diplexer

And how do you know that? Clearly the first thing any engineer/physicists knows is importance of estimating the error, without that your calculations are almost useless.

I understand that the exact number is unknowable, but how low must the probability be that the plane is NOT in the general area where Inmarsat data lead the investigation to that was then shown to house a frequency that is said to be almost impossible to come from anything but the underwater beacon? With these 2 facts, the chances that the plane is not in this area must be approaching zero...correct?

No, a possible track took them to a place where pings from a presumed underwater locator beacon (ULB) could be heard.