Definition
Small, hinged secondary surfaces attached to the trailing edge of a primary flight control (such as an aileron, elevator, or rudder). Tabs are used to reduce the control force the pilot must hold, to trim the aircraft for hands-off flight, or, in some designs, to assist in moving the primary control surface itself. Common types include trim tabs, balance tabs, servo tabs, and anti-servo tabs.
Plain English
Tabs are tiny moveable flaps on the back edge of a bigger control surface. They help the pilot by either holding the controls steady so the pilot doesn't have to keep pushing or pulling, or by helping move the control surface with less effort.
Context Anchor
Seen in discussions of high-speed flight controls, trim systems, and ways aircraft reduce the force needed to move the main controls.
Derivation
From the Middle English 'tab,' meaning a small flap or projecting piece. The aviation use keeps that everyday sense -- a tab is literally a small flap attached to a larger surface.
Why Pilots Care
They make it possible to fly high-speed aircraft safely by keeping control forces manageable and allowing precise trim without fatigue.
Analogy
A tab is like using a small handle to help move a larger door. The small piece does not replace the main surface, but it helps control how the larger surface moves or feels.
Intuition Check
Do not read “tabs” here as paper tabs, browser tabs, or checklist labels. In this context, tabs are small movable aircraft surfaces that help control or balance the main flight controls.
Example Sentence 1
After takeoff and establishing climb, the pilot adjusted the elevator trim tab to relieve the back-pressure on the yoke.
Example Sentence 2
Servo tabs on the ailerons helped reduce the force needed to roll the aircraft at high speed.