Plain English Meaning

A setup that uses pumps, rather than gravity, to move fuel from the tanks to the engine. There is usually a main pump driven by the engine and a backup electric pump the pilot can switch on.

Full Definition

A fuel delivery arrangement used on aircraft whose engine or fuel tank layout cannot rely on gravity to feed fuel to the engine. It uses one or more pumps to move fuel from the tanks, through the fuel lines and filters, to the carburetor or fuel injection system. Most fuel-pump systems include an engine-driven pump as the primary source of fuel pressure and an electric auxiliary (boost) pump used for engine starting and as a backup if the engine-driven pump fails.

Context Anchor

Seen in fuel-system descriptions and in checklist steps for starting, , , and engine-failure .