Definition
A manually operated handle, located in the cockpit of some retractable-gear airplanes, used to mechanically lower the landing gear when the normal hydraulic or electric extension system has failed. The pilot turns the crank a specified number of revolutions to drive the gear down and lock it into the extended position.
Plain English
A handle inside the cockpit that the pilot turns by hand to lower the wheels when the regular gear system isn't working.
Context Anchor
Seen in emergency landing gear extension procedures and aircraft checklists for airplanes with retractable landing gear.
Derivation
Crank comes from an old word meaning a bend or turn. That helps here because a crank is a handle shaped or arranged so turning it by hand can turn a shaft or move a mechanism.
Why Pilots Care
Provides a reliable backup method to lower the landing gear and complete a safe landing when powered systems are unavailable.
Intuition Check
A hand crank is not the same as “cranking” an engine to start it. Here, it means a manual handle used to move a system when normal power is not doing the job.
Example Sentence 1
After the gear motor failed, the pilot used the hand crank to lower the landing gear before landing.
Example Sentence 2
During the preflight briefing the instructor showed where the hand crank is stowed and how many turns are typically required for full gear extension.