Definition
Small illuminated indicators on the instrument panel that announce the status of an aircraft system or autopilot/flight director mode by lighting up, often with a label or color code (green for normal/armed, amber or red for caution or warning).
Plain English
Little labeled lights on the panel that turn on to tell the pilot what a system is doing or to flag a problem.
Context Anchor
Seen on the instrument panel or flight control display when checking autopilot, flight director, warning, and system status indications.
Derivation
From the verb 'announce,' from Latin 'annuntiare' meaning 'to make known.' An annunciator is something that announces — these lights announce a system's status or a warning to the pilot.
Why Pilots Care
They give immediate visual feedback on mode engagement and system health, allowing pilots to stay aware and correct issues quickly without looking away from the flight instruments.
Intuition Check
Do not think of annunciator lights as ordinary lighting for seeing the panel. They are information lights: each one is telling you a specific system status or condition.
Example Sentence 1
When the pilot engaged the autopilot, the 'HDG' annunciator light illuminated to confirm heading mode was active.
Example Sentence 2
A flashing annunciator light alerted the crew to a yaw damper disconnect during cruise.