Use this calculator for flight-planning study or a first-pass cross-check when all inputs describe the same aircraft, atmospheric condition, and phase of flight.

Fuel flow (L/h)

Fuel consumption rate.

Reserve time (min)

Reserve endurance in minutes; FAA VFR day requires thirty, night forty-five.

Compute the reserve fuel needed for a given endurance time and consumption rate. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Reserve fuel (L)

Required reserve fuel volume.

• Do not use a generic calculator in place of the current aircraft flight manual, approved performance data, operating limitations, NOTAMs, weather, or regulations. Real performance changes with configuration, runway condition, altitude, temperature, wind, loading, and technique.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Cross-check the result against the aircraft flight manual or approved planning system, then apply the required safety margins. Keep signed wind, heading, altitude, speed, and fuel conventions explicit.

• Final Reserve Fuel Calculator

  Compute the final reserve fuel needed to hold for a given time at the holding burn rate.

• Endurance Calculator

  Compute how long the usable fuel lasts at a given consumption rate.

• Holding Fuel Required Calculator

  Compute the fuel required to hold for a given time at the expected burn rate.