Just watching a movie with a 4 engine prop plane running out of fuel over
the ocean. So what would be the best way to conserve fuel. I'm thinking
throttle back all four engines and let them loaf along. Or would you cut
two engines and let two carry the load. Two would have to work harder, but
would they use less fuel then 4? Of course, range becomes more important
then speed. Any opinions?


Any four engine aircraft I have been involved with has an optimum
speed that gets you the most distance vs fuel burned called Long Range
Cruise (LRC). For instance on the B-707 that speed was M82, the
B-757 is M80. 3 engine LRC on a 707 is also M82, but range would
suffer slightly because of the increased drag with a windmilling
engine and all the trim you had to crank in.

Back in the cold war days, the Navy P-3's would loiter and chase subs
with 1 amd 4 shut down. That got them the most time on station, but I
doubt that helped the range.