Fuel burn-off percentage
I'm defining fuel-burn off percentage as the proportion of fuel burnt carrying its own weight. Forgive me if there's a more standard term -- that seems to be what Boeing calls it. In considering transport category aircraft, typical figures quoted are 4-5%/hour.
I'd like to estimate the fuel-burn off percentage for a light aircraft. Many light aircraft POHs don't give weight-dependent cruise speed figures. Naively, I would have thought that a 1% increase in weight causes about a 1% increase in drag at best L/D, hence if I fly around at best L/D the whole time the fuel burn-off % is fuel-burn/aircraft-weight. e.g. if I burn 36 kg/hr to fly a 1800 kg aircraft, the burn-off % is 2%/hr. Presumably at typical light-aircraft cruising speeds well above best L/D the proportion goes down.
Does that sound right? Is there a better way to estimate this?