Definition
An automatic flight control subsystem that adjusts engine thrust by moving the throttles without pilot input, holding a commanded airspeed or thrust setting selected through the autoflight system. It works alongside the autopilot, with the autopilot controlling the flight path and the auto throttle controlling the power needed to fly that path.
Plain English
A system that moves the throttles for the pilot to keep the aircraft at the speed or power setting the pilot has dialed in.
Context Anchor
Seen in aircraft equipped with advanced autopilot or flight guidance systems, especially during climb, cruise, descent, and approach.
Derivation
Auto comes from the Greek autos, meaning self. So auto throttle simply means a throttle that moves itself, controlled by the aircraft's flight management system rather than the pilot's hand.
Why Pilots Care
It lowers pilot workload, improves fuel efficiency, and delivers precise speed control that supports safer and more consistent flight operations.
Analogy
Like cruise control in a car, but instead of holding a road speed it holds an airspeed or thrust setting, and the throttle levers actually move on their own as it works.
Intuition Check
Do not assume the auto throttle system flies the airplane by itself. It only controls engine power; the pilot must still monitor speed, attitude, and the flight path.
Example Sentence 1
After takeoff, the captain engaged the auto throttle system to hold the climb speed.
Example Sentence 2
During the approach the auto throttle system reduced thrust smoothly as the airplane descended toward the runway.