Jet Fuel Burn Knots Liters Calculator

Jet fuel burn: F = fuel_flow × time

Crews report fuel burn in kilograms per hour (kg/h), not liters, because density shifts with temperature. Cruise numbers run roughly like this: Airbus A320 ~2,500 kg/h, Boeing 737 MAX ~2,400 kg/h, Boeing 777 ~7,000 kg/h, A380 ~12,000 kg/h. Jet A sits near 0.80 kg/L at 15 °C, which puts 2,500 kg/h at about 3,125 L/h. The efficiency number to watch is Specific Range (nm per kg), and you hit its peak at the long-range cruise Mach and the right altitude. Run the math on a typical A320 domestic leg: 2,400 kg/h × 2.8 h block time = 6,720 kg, or roughly 8,400 L.

Applications

Cost-index economy, where fuel cost is weighed against time cost. Fuel hedging contracts and procurement. The dispatch fuel load (trip + alternate + reserve + contingency + taxi). ETOPS planning, sustainability and CO2 reporting, the evaluation of Sustainable Aviation Fuel (SAF) blends, route economics, and fleet selection all lean on the same figure.

FAQ

Why is jet fuel measured in kg, not liters? What the aircraft cares about is mass, not volume. A liter expands or contracts with temperature; a kilogram stays a kilogram.

What is cost index? A value from 0 to 999 you feed the FMS so it can weigh fuel cost against time cost. CI 0 chases maximum range, CI 999 chases maximum speed.

Does SAF reduce burn? Its specific energy is close to Jet A, so the burn itself barely moves. The payoff sits in lifecycle emissions, where SAF can cut CO2 by up to 80% against fossil jet.