Definition
A device built into a gyroscopic instrument that locks the gyro's gimbals into a fixed, centered position so the instrument can be reset to a known reference. On an attitude indicator, activating the caging mechanism returns the horizon bar to level and stops the gyro from precessing while caged.
Plain English
A small lever or knob on a gyro instrument that, when pulled or pushed, holds the inner spinning parts still and snaps the display back to a neutral, level reading.
Context Anchor
Seen in discussions of attitude indicators, especially older or mechanical instruments that can be caged before use, during startup, or after the display has been disturbed.
Derivation
From 'cage,' meaning to confine or hold something in place. Calling it 'caging' fits the picture: the gyro's freely moving parts are temporarily locked inside a fixed position, like an animal held in a cage, until the pilot releases them.
Why Pilots Care
Protects the delicate gyro from shock and lets the pilot quickly restore an accurate horizon reference after maneuvers.
Grounding Statement
Think of the caging control as the attitude indicator’s way of holding or resetting its internal reference before the pilot relies on the display.
Intuition Check
Do not read “caging” as a storage or protective cover for the whole instrument. Here it means restraining or resetting the moving gyro inside the attitude indicator.
Example Sentence 1
Before engine start, the pilot pulled the caging knob to center the attitude indicator while the aircraft sat level on the ramp.
Example Sentence 2
After a steep bank, the instructor used the caging mechanism to re-erect the attitude indicator to level flight.