Definition
The two primary load-bearing wheels of an airplane's landing gear, mounted under or near the wings and positioned aft of the aircraft's center of gravity. The main wheels carry most of the airplane's weight on the ground and are the wheels that touch down first or last (depending on configuration) during normal takeoffs and landings.
Plain English
The two big wheels under the wings that hold up most of the airplane's weight on the ground.
Context Anchor
You will see this term in takeoff and landing discussions, especially when the airplane’s weight shifts between the main wheels and the nose wheel or tailwheel.
Why Pilots Care
They carry the aircraft's weight during ground operations and directly affect directional control and stability on takeoff and landing.
Intuition Check
Do not read “main wheels” as meaning all the wheels on the airplane. Here it means the primary support wheels on the main landing gear, separate from the nose wheel or tailwheel.
Example Sentence 1
As airspeed increased during the takeoff roll, the pilot eased back on the yoke and the nosewheel lifted off, leaving the airplane rolling on its main wheels.
Example Sentence 2
During the takeoff roll the main wheels remained in contact with the runway while the nose wheel lifted.