Originally Posted by
AAKEE
Thats for the sat com. Would be nice to se the ACARS logs from VHF-com.
Early in investigation it was said that Acars was deliberately shut down.
If so, there should have been some kind of log of on those logs ?
I am not aware of any substantiated report that any system on MH370 was 'shut down'. All we know was that various systems were no longer responding at certain times. We also know that the satcom was 'off' at least twice by the fact that it logged on twice. 'Off' in this sense means that the aircraft terminal was not in a logged on status (due to loosing the signal, being shut down, having power lost, etc.) but doesn't tell the reason it was 'off'.
we have a last Transponder return time, a last ACARS message time, a Last RTF time, several missed phone calls times, but not a single logoff or power down message. Nor do I believe any of those systems generate such a logoff messages.
As such, I don't believe there is any information to establish if systems were individually powered down at their normal power controls, by pulling local circuit breakers, by pulling busses, because breakers popped due to overload, because the device was damaged (other than the satcom which clearly was not damaged in that it came back twice).
The two most obvious path's of speculation are
1 - some technical emergency happened which motivated the crew to power down most of the aircraft's systems and after a reasonable time (at minimum I believe the time between loss of transponder and logon of the satcom) power up at least the Satcom, but not use it.
Or
2 - someone (crew, crew forced by passenger, passenger) did the same series of events with the objective of making the aircraft disappear.
It does seem difficult to imagine a technical emergency that would a- be responded to in such a way, b - allow the aircraft to fly for many hours, c - prevent any communication (particularly given that the satcom was back on line for most of the time)