Fuel affects both total aircraft weight and total moment. A weight and balance calculator therefore needs the usable fuel quantity, an applicable fuel density and the fuel station or arm.
Fuel density
Many light-aircraft POH loading examples use 6 lb per US gallon for aviation gasoline. Jet-fuel aircraft use a different loading density specified by their documentation. Fuel density is set for each aircraft configuration rather than applying one value to every airplane.
Fuel arm
The fuel arm determines how fuel contributes to moment. Burning fuel removes both weight and moment, so the CG can move during flight.
Takeoff fuel, trip fuel burn and landing fuel
A useful weight and balance plan considers not only the fuel carried at takeoff but also the fuel expected to remain later in the flight. WBcalc uses takeoff fuel and planned trip fuel burn to determine expected landing fuel, or can calculate trip fuel burn from entered takeoff and landing quantities.
Expected landing fuel = Takeoff fuel − Trip fuel burn
Takeoff and expected landing fuel are then evaluated as separate loading conditions using the model data represented by the calculator.
Usable versus total fuel
Flight-planning calculations generally work with usable fuel. Unusable fuel is handled according to the aircraft’s empty-weight definition and approved documentation.
Use the exact configuration
Some models have standard, long-range or optional fuel systems. Select a calculator/configuration that matches the airplane and verify it against the POH or AFM.
Calculate weight and balance for your aircraft
WBcalc provides model-specific calculators with aircraft loading stations, fuel data and CG limits. Browse all supported aircraft calculators.
WBcalc is a planning aid. Approved aircraft documents and the current aircraft weight and balance record remain authoritative.