Cessna 152 6 gallons/hr
Cessna 172 10g/hr
Pa28 10g/hr
Any other airplane I'm not familiar with:
Horsepower/2= gallons per hr.
So 310hp equals about 16 gallons an hr with proper leaning.
It basically exceeds book values by 25%.
I like to carry at least 1hr additional fuel above req. tripfuel.
Fuel gauges are for general indications, I keep track of time since engine start.
So eg 10 gallons/hr since engine start-time not since T/O.
Furthermore I have dipsticks for 152/172.
The fuel gauges in the new 172 SP's are reliable enough at least on the planes I fly.When flightplanning suppose we'll have a 10 knot wind 40 degrees cross,I'll count that as a 10knot headwind for trip time calc.
I haven't run out of fuel yet.
Just another thought, I've done a couple of 2000+mile trips in various airplanes, I always do a couple of what I call "check" legs,I fly at a fixed altitude & power setting, land well within fuel limits and check with the fuel bill so I can get an exact fuel burn.
Add 0.5 gallons/hr and that's the fuel burn for the rest of the trip
WHEN IN DOUBT FILL UP
