Originally Posted by GearDown&Locked
I was reading the 85 747 JAL crash report and noticed the fact that they entered in a state of vertical oscillation and from the timeline of the cvr transcript they were in this state for about 30 mins or so.
Would it be possible to stablise an A/C in this condition? I know we're talking about a big and heavy 747, but would it be recoverable on, say, a 737? Thanks.
GD&L
I do not think big and heavy matters much. Actually, it might well be harder on a small plane... The Sioux City DC10 also had phugoids and crashed exactly because of phugoid on landing. Not sure about how the shot-down DHL A300 managed.
What happened was that all three planes suffered loss of all hydraulics and therefore all hydraulic control surfaces froze. The remaining control was throttles.
Sioux City DC10 had 2 throttles for control because the middle engine had exploded, while the DHL A300 had 2 throttles because there only were 2 engines to begin with. The JAL 747 would have had 4 throttles, so in principle slightly more degrees of control... but exactly how does inboard/outboard thrust affect a 747?