AVGAS

AVGAS, which stands for Aviation Gasoline, is a type of aviation fuel. It comes in various grades, indicated by its octane rating (which measures resistance to pre-ignition). The most common grade is 100LL. This means the fuel has an octane rating of 100 and contains a low lead content. It’s recognizable by its blue color.

The 100LL is gradually being replaced by UL91, a lead-free fuel. UL91 is miscible with 100LL and can also be used in light aircraft that typically use MOGAS SP98 (Motor gasoline). UL91 is colored red to distinguish it from 100LL.