[Ron throws his oar in]

On Thu, 4 Dec 2003 20:24:00 -0500, "Mark" wrote:

Does a prop turning at 2300 rpm on a 150hp motor produce more thrust than a
prop spinning 2300 rpm on a 100 hp motor ?

Assuming the engines are mounted on a ground test stand, and the propellers
are "normal" (no paddlewheels, etc.):

If the props are identical fixed pitch propellers, the same thrust is
produced. Both engines are producing the same power.

If the engines are NOT producing the same power, it is because their
throttle positions and the propellers. Either may produce more thrust,
depending on the combination of the two parameters. For instance, the 150
HP engine could have controllable-pitch prop at flat pitch....it might turn
2300 with the throttle barely cracked.

If both engines are producing their rated horsepower, the 150 HP engine
produces more thrust. Its propeller must move more air in order to absorb
the higher power at the same RPM.

Ron Wanttaja