Aviation Gasoline

Avgas or aviation gasoline is an aviation fuel. It is usually used in spark-ignited internal-combustion engines of aircrafts. Avgas is different from mogas (motor gasoline), which is the general gasoline used in automobiles and some light aircrafts.

Unlike mogas, which has platinum-content catalytic converters for pollution reduction, some types fo aviation gasoline still contain tetraethyllead (TEL) to prevent engine knocking (detonation).

The major petroleum component that is used in blending avgas is alkylate, a mixture of numerous iso-octanes. Some refineries also blend reformate in Avgas. All Avgas grades that meet CAN 2-3, 25-M82 have an average density of 6.01 lb/U.S. gal at 15 °C, or 0.721 kg/l.

Avgas has a lower and more uniform vapour pressure than automotive gasoline. That keeps Avgas in the liquid state even in reduced atmospheric pressure at high altitude, resulting in avoidance of vapour lock.

Avgas is now available in many grades with differing maximum TEL concentrations.