I believe the pilot possibly trained and practiced this potentially deadly 42,000 ft climb maneuver with a sharp bank U-turn on his homemade simulator until he perfected it. It takes a large amt of air space to make a 777 safely U-turn. I believe he preprogrammed this 777 jet, Flight MH370, to make certain particular maneuvers.
The 777 flew one hour before banking a hard U-turn. Immediately, the plane climbs to 42,000 ft. That is almost eight miles from [the ground] at sea level pressure. For reference, 32,000 - 37,000 ft is normal for 777s. The plane went at least 5000 ft higher than the maximum suggested range and as many as 10,000 ft higher than recommendations.
Reconnaissance planes fly at 100,000 ft above sea level pressure.
Theoretically, passengers would have seconds to reach their O2 masks during a pressurized a rapid ascend. It is imperative that the plane not remain at this altitude without O2 for everyone. The plane must descend fairly soon thereafter, for safety's sake.
East bound are assigned odd #s and west bound are assigned even #s. 42,000 ft indicates flying West bound, if assigned.
Pilots have their own O2 access in the cockpit. The 777 descends to normal altitude and cruises. ATT, the 777 had appx six hours of fuel left and cannot be refueled in midair. The lower a plane flies, the more fuel it consumes.
*The arc in the image shows where the 6 hrs of fuel remaining could take the 777 from the origination indicated by the tiny white airplane.
<RSBM>
this is the area they are still focusing in, also known as the "arc"
The 3 dots in the western Indian Ocean are Male, Abbu Atoll, and Diego Garcia.
OMO