Cruise RPM

[backcast]

I've been attempting to find the best RPM for cruise flight. The L4 Military Manual states for maximum cruise: RPM 2000 @48hp (A65 motor). The A65 manual states the recommended cruise RPM is 2150. I think my best cruise (best meaning highest mph w/least RPM, economy of fuel) 2050 rpm, I have a wood 72/42 prop.

Any thoughts out there? Is there a science to finding best RPM?

Tedd

 

[chuck2shaw]

 

[Paul Smith]

 

[chuck2shaw]