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Old 11-04-2009, 03:35 AM   #8 (permalink)
Frank Lee
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Quote:
Originally Posted by SentraSE-R View Post
From my experience in smaller propeller planes, they do operate at best BSFC all the time after takeoff is completed.
You made the key point right there.

There's no need for "pulse" as we think of it in automotive terms cuz cruise loads a/c engines accordingly for the duration.

That is another reason why you generally can't just pluck an automotive engine out of a car and stick it into an aircraft. The duty cycles are waaay different, with the auto engine loafing along most of it's life with brief periods of higher load, and the a/c engine working pretty hard most of it's life, with brief periods of even higher load. That's why we ought not laugh too hard at an a/c engine that uses, say, 330 cubic inches to put out 100 hp. It's not because the engineers were dense.

There are motorized gliders that I suppose could be considered "pulse-and-glider(ers). They aren't in it for the fe though. They are mostly for recreation- not seriously trying to get from a to b- and the motor gets the tow plane out of the equation and allows for more thermals-hunting per mission anyway.
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