krispy kreme. regarding fuel tank. while Idon't fly the 777, I do recall that the TWA explosion was around 13,000' and the ullage was a factor due to temps, being at35000 it would be nice and cool.
HOWEVER any explosion could damage the cable between the cockpit and the transmitter and or antenna. Thus any attempt at communication might not work.
for those mentioning fuel exhaustion or starvation, it should be noted at 777 at FL350 should easily be able to glide in excess of 100 miles (zero wind).
On tV someone reminded me of the BAE146 operated by the then PSA in which an angry employee got aboard with a gun and shot the pilots and the plane crashed into the ground in california sort of near paso robles. no radio call there.