For a fast back of the envelope calculation of fuel flow when the POH is not handy, Knock the last zero off the horsepower and that will be your fuel flow at takeoff power in US Gal/hr. Half of that will be your fuel flow at 65 % power.
eg 150 hp engine = 15 Gal/hr at full throttle and 7.5 Gal/hr at 65 % power.
Last edited by Big Pistons Forever; 22nd Apr 2013 at 23:17.