Plain English Meaning
The parts of the autopilot that tell it whether the aircraft is climbing, descending, banking, or turning, so it knows what to correct.
Full Definition
Devices that detect changes in aircraft attitude and rate of motion by sensing the behavior of a spinning mass (or its modern electronic equivalent) that resists changes in its orientation. In an autopilot system, these sensors supply the pitch, roll, and yaw information the autopilot uses to determine what the aircraft is doing and what corrections are needed.
Context Anchor
Seen in autopilot system descriptions, where the autopilot needs reliable information about the aircraft’s motion and position before it can make control corrections.
Derivation
From the Greek 'gyros' meaning '' or 'turn' and 'skopein' meaning 'to look at' — literally a device for observing . The name reflects the original spinning-wheel design, though many modern units are .