Which surface performs the same function as the horizontal stabilizer + elevator combination?

• A. Elevator
• B. Aileron
• C. Flap
• D. Stabilator

Answer: (D)

Pitch control at the tail is achieved by deflecting a surface to change the tail’s angle of attack and produce a pitching moment. An all-moving horizontal stabilizer, called a stabilator, moves the entire tailplane as one piece to provide that same pitch control, effectively combining the stabilizer and elevator into a single surface. Because the whole tailplane moves, the surface can produce more abrupt or responsive nose-up/nose-down moments, similar to what the separate stabilizer plus elevator would do.

An elevator alone is just the movable portion of the tail and relies on a fixed stabilizer to work; it doesn’t replace the stabilizer. Ailerons control roll, not pitch, and flaps affect lift on the wings rather than the tail’s pitch control. So the stabilator is the surface that performs the same function as the horizontal stabilizer plus elevator.