small hinged portion of trailing edge of flight control surface adjusted by pilot to hold the aircraft in trim
A small auxiliary surface hinged on an airplane's control surfaces, used to bring it into balance or trim. This may be as simple as a small metal tab on the trailing edge of an elevator that is set to trim the aircraft for horizontal flight.
a small, adjustable hinged surface on the trailing edge of the aileron, rudder, or elevator control surfaces
a small flap attached to the trailing edge of a larger control surface which is used to keep the larger control deflected
a small rudder at the end of a large rudder on a plane or ship
A small area generally to the rear of a control surface which is used to trim out the forces necessary to keep an aircraft flying straight and level with hands off.
Trim tabs are small surfaces connected to the trailing edge of a larger control surface on a boat or aircraft. The angle of the tab relative to the larger surface can be adjusted to null out hydro- or aero-dynamic forces and stabilize the boat or aircraft in a particular desired attitude without the need for constant control inputs.