Plain English Meaning

The liquid an aircraft burns to make its engine run. Different aircraft use different types: piston engines burn avgas, and jet engines burn jet fuel.

Full Definition

A combustible substance that, when mixed with air and ignited inside an engine, releases energy used to produce thrust or mechanical power. In aviation, fuel typically refers to aviation gasoline (avgas) for piston engines or jet fuel (kerosene-based) for turbine engines.

Context Anchor

Seen during fueling, preflight inspection, fuel sampling, maintenance, and any of chemical around aircraft.