Originally posted by Batz
I know what you meant but you travel a whopping 1.5 miles further at 3000rpm then at 2000.
The difference between the fuel you burned and the speed increase easily makes that up.
So you may run out fuel faster but you cover more ground.
The first approximation for the power output at 4krpm compared to 3krpm is a factor of 1.33. With 1.33 times the power you go about 1.07 times as fast. This is what you can see in the measured values. (11/10, 13/11.5).
The values are the same because fuel consumption does not depend on rpm in AH. Again, at 4krpm compared to 3krpm 1.33 times as much fuel should be used per time.
So at 4krpm the aircraft is 1.07 times faster, but flies 0.75 times as long as at 3krpm. If it does 10 miles/25% fuel at 3krpm, it should fly 8 miles at/25% fuel at 4krpm.
Just approximations, but actual values should come close.
