Plain English Meaning

Electricity plugged into the aircraft from outside, usually so the engine can be started or systems can be checked without using up the battery.

Full Definition

Electrical power supplied to an aircraft from a source outside the aircraft, typically through a receptacle in the fuselage, used to start the engine or operate electrical systems on the ground without drawing on the aircraft battery.

Context Anchor

Seen during ground operations, engine starting, maintenance, and preflight checks on aircraft equipped with an external power connector.

Derivation

‘External’ comes from the Latin externus, meaning ‘outside.’ In this context it simply signals that the power source is not part of the aircraft itself — it is supplied from outside.