"Peter Duniho" wrote in message
...
"Mike Rapoport" wrote in message
nk.net...
I don's see that I've overlooked something relative to the Caravan. The
Caravan has a 940hp engine. There is currently no suitable piston engine
to
power such a large, single engine airplane. It couldn't be anything
other
than a turbine.

As you yourself pointed out, that 940hp engine is derated to 675hp. You
don't need a 940hp piston engine to provide the equivalent power, and a
675hp piston engine is not out of the question (for example, the Orenda V8
turbine replacement engines are in that ballpark, if I recall correctly).

Large snip.

I agree that it is difficult to compare different types of engines apples to
apples since the power and specific fuel consumption curves are so
different.. I have two airplanes, one turbine and one piston. Both engines
are well suited for their applications. In the Helio, power is often set to
15"MP to keep the speed down in turbulent, low altitude mountain flying. A
turbine would be horribly inefficient operated like this. In the MU-2,
power is set close to the torque or temp limits from takeoff until reaching
about 16,000' on the descent. A piston engine operated flat out like this
wouldn't last long, particularly at high altitude. Both powerplanes have
their place although I think that diesels will eventually replace gasoline
piston engines because of their efficiency, long life and simplicity.

Mike
MU-2