Definition 1 of 2
Definition
A landing gear system that the pilot can mechanically or hydraulically retract into the airframe after takeoff and extend before landing, reducing aerodynamic drag during cruise flight.
Plain English
Wheels that fold up into the airplane after takeoff and come back down before landing, so they don't slow the airplane down while flying.
Context Anchor
Seen in airplane systems discussions, preflight checks, takeoff procedures, before-landing checks, and emergency procedures for airplanes equipped with movable gear.
Derivation
From the Latin retrahere, meaning 'to draw back.' The gear is literally drawn back into the airplane after takeoff.
Why Pilots Care
Retractable gear reduces drag and improves cruise speed and fuel economy, but it adds mechanical complexity, weight, and the requirement to manage extension and retraction sequences on every flight.
Grounding Statement
Picture the wheels down for landing, then pulled up after takeoff so the airplane moves through the air more cleanly.
Intuition Check
Retractable does not mean removable or optional here. It means the landing gear is built to move up and down as part of normal airplane operation.
Example Sentence 1
After a positive rate of climb, the pilot raised the gear handle and confirmed the retractable landing gear was fully stowed.
Example Sentence 2
During the before-landing checklist the pilot verified the three green lights indicating the retractable landing gear was down and locked.