Definition
A condition in which a moving indicator, such as a meter needle or pointer, comes to rest at its final reading without overshooting or oscillating around it.
Plain English
When a needle or pointer moves to a value and stops cleanly there, instead of swinging back and forth before settling, it is said to be deadbeat.
Context Anchor
Seen in aircraft instrument descriptions, maintenance discussions, and checks of whether a gauge gives a stable reading.
Derivation
From 'dead' meaning motionless and 'beat' meaning a swinging or oscillating motion. A deadbeat instrument is one whose swinging is killed off, so it settles immediately rather than vibrating around the reading.
Why Pilots Care
Gives immediate, stable readings without waiting for the needle to settle, which is essential during turbulence or rapid maneuvers.
Intuition Check
Deadbeat does not mean broken, lazy, or unreliable here. In this context, it means the instrument is damped enough to stop at the reading without bouncing around it.
Example Sentence 1
The new ammeter has a deadbeat movement, so the needle settles on the correct reading immediately after the load changes.
Example Sentence 2
During the climb the deadbeat airspeed indicator gave a steady reading even as the aircraft passed through light turbulence.