Quote:
Originally Posted by Checkboard
So, time for a "Rule of Thumb"
When a piston twin loses an engine, it has to slow form its normal cruise speed (with lots of parasite drag) to close to the long range speed. You will find that the aircraft is flying more efficiently on one motor at the single engine cruise speed, than on two at normal cruise! (but not as efficiently as on two at long range cruise, due to the added drag of the engine out thing.)
So the aircraft will fly furthur (through the air) one one engine than on two! Doesn't work for turbines, as they are forced to operate at a (inefficient) lower altitude.
Seem to remember a wriiten procedure from the old days on the Beech 99
where if you were in a situation of not having enough fuel to destination(remote area), you could shut down one engine to extend range. Can anyone cofirm?
Lets look at these two statements in isolation.
As regards the piston twin...only a few can do as advertised in the quote, the CV440 is one of those that I have flown.
Driftdown is however, a distinct possibility.
As regards the BE99....only at very light weights.
The BE99 wing was was optimized for lower altitudes, as the airplane is unpressurized.