"Mike Rapoport" wrote in message
ink.net...
Actually a constant speed prop converts HP into thrust about the same at
all (reasonable) altitudes. That is one of the great advantages of a CS
prop.

Really? I just assumed that with air density lower, the prop (CS or
otherwise) had less air available to move, and thus could not produce
sea-level thrust.

I guess in that case, my longer take-off runs are solely due to the higher
true speed required. Still, that's a significant effect. I just don't want
anyone thinking that a turbocharger makes high-altitude takeoffs just like
sea-level.

Pete