Definition
An in-flight failure of the cockpit lighting system that illuminates the flight instruments, navigation instruments, and engine gauges, leaving the panel partially or fully unreadable in darkness. It is a foreseeable night-flight emergency requiring the pilot to use a backup light source (typically a flashlight) to continue scanning the instruments and complete the flight safely.
Plain English
The lights that let you read your cockpit gauges at night stop working, so the panel goes dark while you are flying. You then have to use a flashlight to see the instruments until you land.
Context Anchor
Encountered during night-flight preflight checks, cockpit lighting checks, and in-flight situations where a pilot must still read the instruments after dark.
Why Pilots Care
Loss of instrument visibility at night can lead to spatial disorientation if not addressed promptly with backup lighting.
Grounding Statement
At night, a working instrument is only useful if the pilot can see it clearly enough to read it.
Intuition Check
Do not assume an instrument light failure means the instrument itself has failed. The problem is the lighting; the instrument may still be operating normally.
Example Sentence 1
Before every night flight, the pilot stowed a small flashlight within easy reach in case of an instrument light failure.
Example Sentence 2
Before takeoff at dusk the pilot confirmed there was no instrument light failure by testing the panel illumination.