Definition
The principal wheels and supporting struts of an airplane's landing gear system, positioned near the aircraft's center of gravity, that carry most of the aircraft's weight on the ground and absorb the primary loads during landing, takeoff, and taxi.
Plain English
The two main wheels under the airplane that hold up most of its weight on the ground and take the brunt of the impact when landing.
Context Anchor
You will see this term in landing gear descriptions, preflight inspections, landing discussions, and procedures for airplanes with retractable gear.
Derivation
"Main" means principal or primary. "Landing gear" refers to the structure that supports the airplane on the ground. Together: the primary set of wheels and struts that do most of the work during landing and ground operations, as opposed to the smaller nose or tail wheel.
Why Pilots Care
It determines stability and load handling during touchdown and taxi, directly affecting safety margins.
Intuition Check
“Main” does not mean all of the landing gear. It means the primary gear that carries most of the airplane’s weight; the nose gear or tailwheel is separate.
Example Sentence 1
The pilot held the nose off the runway after touchdown so the main landing gear absorbed the rollout loads.
Example Sentence 2
Before flight the mechanic inspected the tires and struts on the main landing gear for proper pressure.