Partial ping at 8.19
There have been a few comments on the partial ping at 8.19 (including latest one that it may be been when aircraft sank). Most seem to suggest that the ping could have been caused by power being cycled off and on to satellite system on the plane causing it to restart and sending ping to satellite. I am not an expert on these large aircraft but from what others have said this could be caused by the first engine shutting down due to fuel exhaustion which then caused power interruption as systems switched over to power supply from the other engine.
The question would then be why only a partial ping? Obviously one possibility is that power was then lost again but could another reason be unusual attitude of the plane? I don't now about 777 but on smaller/older aircraft loss of an engine will cause autopilot to disconnect and if pilot doesn't stop it pretty quickly the asymmetrical thrust will cause plane to rapidly bank towards dead engine and potentially enter a spiral dive, etc.
Just wondering whether anyone with more experience on these aircraft can comment on whether autopilot will remain connected when first engine fails and if not whether there would be anything (other than a conscious pilot of course!) that would stop the aircraft rapidly losing control (which could explain the partial ping if the satellite antenna was no longer pointing skywards??).