If you wish to contribute or participate in the discussions about articles you are invited to join SKYbrary as a registered user


Trim Tab

From SKYbrary Wiki

Article Information
Category: General General
Content source: SKYbrary About SKYbrary
Ambox content.png
The present article is under construction.
Reader enquiries are welcome, contact the editor: editor@skybrary.aero.
Ambox content.png


Trim tabs are small, secondary flight control surfaces that are attached to the trailing edge of a larger, primary control surface such as an elevator or rudder. The trim tab is used to "trim", or counteract the aerodynamic force on, the control surface and thus stabilise the aircraft in the axis of rotation associated with the primary control. Trim tabs can be either flight adjustable or fixed.

By adjusting the angle of the trim tab relative to the larger control surface, the neutral position of the control surface is changed. This occurs because the distance from the control surface hinge or arm at which the trim tab is mounted provides sufficient [[Moment|moment] to move the larger surface.

Fixed tabs are most often encountered on a light, single engine aircraft. A fixed tab is ground adjusted (bent) to the desired position to overcome any unwanted roll or yaw tendencies of the aircraft. On aircraft equipped with adjustable trim tabs, the position of the tab can be changed in flight, using cockpit controls, to counter any change in control loading caused by airspeed, centre of gravity, aircraft configuration or engine failure. Trim tab control can be manually or electrically actuated, depending upon the aircraft.

Related Articles