How to use this calculator
- Enter usable fuel. Use usable fuel, not total tank capacity if unusable fuel is listed.
- Enter reserve fuel. Set aside the fuel reserve you want to keep.
- Enter fuel burn. Use the expected cruise burn rate.
- Enter ground speed. Use expected ground speed for range.
How it works
The core formulas are endurance = fuel / fuel burn and range = ground speed x cruise time.
Use this with true airspeed, descent planning and wind components.
Worked example
Verified against the live calculator
With 50 gal usable, 8 gal reserve, 9 gal/h burn and 115 kt ground speed, cruise time after reserve is about 4.7 hours and still-air range is about 537 NM.
Frequently asked questions
How is aircraft endurance calculated?
Endurance is usable fuel divided by fuel burn rate.
How is still-air range calculated?
Still-air range is ground speed multiplied by usable cruise time after reserve fuel is removed.
Does this include wind?
Only through the ground speed you enter. Use wind-corrected ground speed for realistic planning arithmetic.
Can this replace required fuel planning?
No. Use regulations, aircraft manuals, winds, alternates, reserves and operator procedures for real planning.
Method & assumptions
- Assumes constant burn rate and entered ground speed.
- Does not include climb/descent fuel, leaning differences, alternates, holding, unusable fuel, weather deviations or regulatory reserve rules.