Definition
Two categories of landing gear distinguished by whether the wheels remain in place during flight or fold away into the airframe. Fixed landing gear stays extended at all times and cannot be moved. Retractable landing gear is mechanically stowed inside the wings, fuselage, or engine nacelles after takeoff to reduce aerodynamic drag, and is extended again before landing.
Plain English
Some airplanes have wheels that stay down all the time. Others have wheels that fold up into the airplane after takeoff and come back out before landing. The first kind is called fixed gear. The second kind is called retractable gear.
Context Anchor
Seen when learning aircraft systems, preflight inspection, performance, and before-landing checklist procedures.
Derivation
Fixed simply means held in place and not movable. Retractable comes from the Latin retrahere, meaning to draw back. The wheels are literally drawn back into the airplane. Knowing this makes the operating idea easy to picture: one stays put, the other pulls in.
Why Pilots Care
Fixed gear is simpler and lighter but adds drag that limits speed and fuel efficiency; retractable gear reduces drag for better performance but adds weight, cost, and maintenance needs.
Intuition Check
“Fixed” does not mean stronger or safer by itself; it means the gear does not move up and down in normal operation. “Retractable” does not mean optional for landing; it must be lowered before touchdown.
Example Sentence 1
The training airplane had fixed landing gear, so the student never had to remember to lower the wheels before landing.
Example Sentence 2
The pilot selected the retractable landing gear handle after takeoff to reduce drag and increase cruise speed.