QUESTIONOn an airplane equipped with a stabilator, the pilot moves the control so that the trailing edge of the stabilator moves down. What does the full-length anti-servo tab do?
- AMoves down, creating a force that resists the stabilator's movement
- BMoves up, creating a force that helps the stabilator continue moving
- CStays neutral, since it acts only when the hydraulic system fails
Show the answer and explanation
Correct answer: A. Moves down, creating a force that resists the stabilator's movement
- A — correct As the stabilator trailing edge moves down, the anti-servo tab also moves down and creates a force trying to raise the trailing edge. This opposing force reduces the stabilator's sensitivity to pilot input.
- B — incorrect Moving opposite to the control surface and assisting its movement describes a balance tab, not an anti-servo tab.
- C — incorrect A tab that provides the sole force to move a control after a hydraulic failure is a servo tab on large airplanes. The anti-servo tab works continuously.