Definition
The aerodynamic resistance produced by the wheels, struts, and associated structure of the landing gear as the airplane moves through the air. On a fixed-gear airplane this drag is always present; on a retractable-gear airplane it is significant during takeoff, climb, and approach when the gear is extended.
Plain English
The extra air resistance the airplane has to push through because the wheels and their supporting structure are sticking out into the airflow.
Context Anchor
Seen in soft-field and rough-field takeoff technique, especially while the airplane is accelerating before liftoff.
Derivation
Drag comes from an old word meaning to pull or draw along. That helps here because landing gear drag is a backward pull on the airplane’s motion, whether from air flowing around the gear or from the wheels resisting movement on the ground.
Why Pilots Care
Leaving the gear extended too long after takeoff increases total drag, reduces climb rate, and can prevent clearing obstacles or cause the airplane to settle back toward the surface.
Intuition Check
Do not think of drag here as something being pulled behind the airplane. In this context, drag means resistance that opposes the airplane’s forward movement.
Example Sentence 1
After lifting off from the soft field, the pilot kept the airplane in ground effect to accelerate, then retracted the gear to reduce landing gear drag before establishing the climb.
Example Sentence 2
On a short rough runway the pilot accepted some landing gear drag initially to keep the nose wheel light, then retracted the gear once a positive climb was established.