Definition
A rapid, repetitive vibration or oscillation in a mechanical or electrical component, typically caused by a part making and breaking contact in quick succession. In aviation, it is most often used to describe the behavior of relays, switches, or voltage regulators when contacts open and close repeatedly instead of holding a steady position, or to describe the audible buzzing this produces.
Plain English
A part is opening and closing very quickly over and over again, instead of staying firmly open or firmly closed. It usually makes a buzzing or rattling sound and is a sign something isn't working smoothly.
Context Anchor
Seen during aircraft electrical troubleshooting, especially when a relay, switch, or circuit breaker is clicking rapidly or causing equipment to turn on and off intermittently.
Derivation
From the everyday word 'chatter,' meaning rapid, repeated noise — like teeth chattering from cold. The aviation use borrows the same idea: a part making fast, repeated contact instead of holding still.
Why Pilots Care
Left uncorrected it can progress to structural damage, loss of propeller efficiency, or control-surface flutter.
Analogy
It is like holding a light switch halfway so the light flickers instead of staying fully on or fully off.
Intuition Check
Chattering does not mean any random cockpit noise. Here it means a switching part is rapidly making and breaking an electrical connection.
Example Sentence 1
The pilot noticed the ammeter needle flickering and suspected the voltage regulator was chattering.
Example Sentence 2
High-speed flight produced chattering in the ailerons that disappeared after the mechanic rebalanced the control surfaces.