Data Guy:
I note that you share my opinion that an MEC fire is possible and might explain what happened. Boeing recommended fitment of upgraded insulation in the MEC after the ground incidents but also suggested better procedures for keeping them free of contaminants such as oil, hydraulic or deicer fluids, which degrade the protection level of the fabric. One wonders how diligently Malaysian were doing this and also if they incorporated the recommended improvements to the MEC cooling for hot region operation.
Olasek. Flash8. Porterhouse.Ian W.:
I am simply suggesting that if the crew were faced with a dual fmc failure it might explain the rather perplexing routeings after contact was lost. Since some of you seem to have no idea how alternate nav works:
A dual fmc failure followed by a 90 degree left turn to start a diversion would leave a completely black ND with no nav aids tuned or nav aids/station data etc available to display. Since nothing would be coming from the FMCs all new waypoints would have to be loaded by lat/long. Until that was done there would be NOTHING to navigate by and situational awareness could be rapidly lost. So, yes, they would have been punching in lats & longs IF there was a dual fmc failure. The quickest way to find a lat/long is to look at the chart and pick a waypoint near where you want to go, AGARI for instance. Then add a few more followed by lat/long of Penang. You are then back in LNAV with a track displayed. My supposition is that the lat/long of Penang might have been entered incorrectly as a South latitude and that after a crew incapacitation the aircraft simply navigated south to that point.
A possible flaw in this argument was that the longitude of Penang is too far east of where the search was being conducted, but the news that they are now switching the search 1000km further east tends to support my theory.