Alex Airplane Trim Devices

Question 1

Trim Devices

Answer 1

Some airplanes may include small hinged trim devices attached to the trailling edge of one or more of the controll surfaces. These mechanisms are used to help minimize your work load by aerodynamically helping you move a control surface, or maintain the surface in a desired position. One such device commonly used on many training airplanes is called a trim tab. If an airplane uses only one trim tab, it is usually located on the elevator.

Question 2

Trim tab

Answer 2

If an airplane uses only one trim tab, it is usually located on the elevator

Question 3

Trim Tab Function

Answer 3

The trim tab lessens the resistance you feel on the flight controls due to air flow over the associated control surface. The trim tab located on the elevator, is controlled by a wheel in the cockpit.

Question 4

Anti-Servo

Answer 4

A stabilator normally uses an anti-servo tab to provide you with a control “feel” similar to what you experience with an elevator. Without the anti-servo tab, control forces from the stabilator would be so light that you might “over control” the airplane or move the control wheel too far to obtain the desired result. The anti-servo tab also functions as a trim to maintain the stabilator in the desired position.