Stabilator

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A stabilator is an all-moving horizontal tail surface that combines the functions of a fixed stabilizer and a movable elevator. It provides pitch control and longitudinal stability, helps with aircraft balance, and can reduce drag at high speeds. The name comes from stabilizer + elevator; it is also called an all-moving tailplane or other similar terms.

How it works: The stabilator moves as a single surface, usually pivoting around the tail’s aerodynamic center near the mean quarter-chord. This keeps the pitching moment more constant and lets the pilot generate control with less force. To make sure pilots feel some resistance to big inputs, small airplanes add an anti-servo tab that moves the same way as the stabilator and provides drag against the control input.

Examples: General aviation aircraft with stabilators include the Piper Cherokee and the Cessna 177. Early all-moving tails appeared on pioneer and fighter aircraft and were sometimes unstable or hard to fly without modern systems. Stabilators were developed for better pitch control at high speeds and are common on many modern military aircraft. The Boeing B-47 Stratojet was the first jet bomber with a one-piece stabilator in service; later designs and configurations varied. The F-86 Sabre originally used a conventional tail but was later equipped or redesigned to use a stabilator in some variants.

Roll control and other designs: When a stabilator helps control roll, that surface can act like elevons (rolling tails). A canard is a separate forewing, not a stabilator. Modern fighters often use fly-by-wire controls, so there is no direct stick-to-surface linkage.

Airliners and trim: Most large airliners use a separate, adjustable horizontal stabilizer and an elevator, controlled by autopilot or manual trim. The stabilizer is trimmed, not controlled directly by the pilot, and is adjusted to keep the pitch axis in trim as speed and weight change. The Boeing 737 uses an electrically powered jackscrew to trim its stabilizer. A true stabilator installed for flight control is exemplified by the Lockheed L-1011 TriStar.