Definition
Small, adjustable surfaces hinged to the trailing edge of the elevator that the pilot sets from the cockpit to relieve continuous control-wheel pressure needed to hold a desired pitch attitude. When deflected, a trim tab produces a small aerodynamic force that holds the elevator in the position required to maintain the trimmed pitch, allowing the aircraft to fly hands-off in stable conditions.
Plain English
Tiny moveable flaps on the back edge of the elevator. The pilot adjusts them so the airplane will hold a chosen nose-up or nose-down attitude on its own, without having to keep pulling or pushing on the control wheel.
Context Anchor
You encounter elevator trim tabs during preflight inspection, when setting trim before takeoff, and when adjusting trim after changes in speed, power, or loading.
Derivation
‘Trim’ comes from an Old English word meaning to set in good order or balance — the same sense used in sailing, where a boat is ‘trimmed’ so it sits level. ‘Tab’ simply means a small flap or strip. Together: a small flap that puts the airplane in balance.
Why Pilots Care
Proper use reduces control forces, prevents fatigue on longer flights, and enables precise hands-free pitch control after weight or configuration changes.
Intuition Check
Elevator does not mean a lift in a building here; it means the tail surface that helps move the airplane’s nose up or down. Trim does not mean cutting or making something neat here; it means adjusting the airplane so it holds the desired nose position with less pilot effort.
Example Sentence 1
After leveling off in cruise, the pilot adjusted the elevator trim tabs until the control wheel could be released without the nose pitching up or down.
Example Sentence 2
Following a change in passenger seating, the pilot reset the elevator trim tabs so the aircraft would maintain level flight without constant yoke input.