Tip:
Highlight text to annotate it
X
Those trying to draw conclusions from the information trickling from the investigation
into the disappearance of Malaysia Airlines Flight 370 should go carefully.
It is plausible that, as Malaysia's Prime Minister asserted, the plane's flying for
hours after losing contact with air traffic control was "consistent with deliberate action,"
but it's not the only logical explanation of the airplane's bewildering trajectory.
Statements that the Aircraft Communications Addressing and Reporting System was intentionally
disabled, for example, leave out the fact that the ACARS is required to send the satellite
contact requests (so-called "handshakes") that, according to news reports, were reported
to have occurred for hours after the flight's disappearance.
The plane has multiple functions and channels connected to the ACARS and at least some of
it must have still been working. For example, one part of this communications
system is used for messages between the airplane and air traffic control (clearances, position
reports, etc). Another is used to communicate, essentially with text messages, between the
airplane and the airline. Messages can also be sent automatically for maintenance functions
such as reporting faults and sending routine engine data. The range of functions that would
have been available for someone to disable is not yet clear.
And at least one news report described altitude excursions between 45,000 feet and 23,000,
which one pilot suggested might have been done willfully to render passengers unconscious.
But this strikes me as behavior that would also be consistent with the airplane flying
completely unattended with the autopilot off. Though these oscillations are larger than
I might expect, it would be a natural behavior for the airplane to fly relatively large but
gentle pitch oscillations. This would be true especially if the airplane's
auto-throttles were also for some reason disabled. There have been statements made that such
changes could only be made by a skilled aviator, but what "skilled aviator" cannot hold altitude
within 20,000 feet? Incapacitation or something else that could
prevent the crew from controlling the plane -- fire, collision, explosive depressurization
-- could also be indicated, which wouldn't necessarily mean the cockpit was breached
by anyone. The airplane reportedly made "suspicious turns."
However, it is the nature of those turns that will reveal if it was deliberate "heading"
(directional) changes or if nobody was flying the airplane at all. If the autopilot was
off and the airplane was essentially flying on its own, I would expect a variety of heading
changes. These changes could be initiated by turbulence during flight.
If the airplane's routes were controlled intentionally by selecting the heading or by programming
the flight management computer, the flight path would be very straight, then a turn that
would last usually from 10 to 30 seconds, followed by more straight flight.
While a close-up analysis of the flight path would be required to determine the case, it
seems that officials are not even sure if the flight path headed northwest toward Pakistan
or southwest into the vast Indian Ocean.