Definition
A mechanical lifting device powered by an electric motor, used in some retractable landing gear systems to extend and retract the gear by driving a screw jack or similar linear actuator at each gear leg.
Plain English
A small electric motor that turns a screw to push the landing gear down or pull it up. The motor does the lifting work that hydraulic pressure does in other airplanes.
Context Anchor
Seen in retractable landing gear systems, especially when describing how the gear is moved up or down after the pilot selects a gear position.
Derivation
A 'jack' has long meant a device for lifting heavy loads — the same idea as a car jack. 'Electrically-driven' simply means an electric motor provides the force instead of a hand crank or hydraulic fluid.
Why Pilots Care
Knowing this term helps pilots understand electric gear systems, recognize failure modes limited to electrical issues, and follow appropriate emergency procedures.
Intuition Check
Do not picture a portable jack used to lift a car. Here, the jack is a built-in powered device that moves the landing gear itself.
Example Sentence 1
On this airplane, an electrically-driven jack at each main gear leg extends the wheels when the pilot selects gear down.
Example Sentence 2
With the battery low, the electrically-driven jack moved the gear more slowly than usual.