Definition
A unit of measurement for the luminous intensity of a light source. One candlepower is approximately equal to the light produced by a standard candle, and is used to rate the brightness of aircraft lamps such as landing lights, taxi lights, and beacons.
Plain English
A way of measuring how bright a light is, based on the brightness of a single candle. A higher candlepower number means a brighter light.
Context Anchor
Seen in descriptions of aircraft lights, airport lights, beacons, landing lights, and other lighting equipment.
Derivation
From candle plus power. The unit was originally defined by the light output of a standard candle of specified size and material, which is where the name comes from. Modern measurements use more precise scientific standards, but the term stuck.
Why Pilots Care
Ensures lights are bright enough for safe night flying and compliance with visibility rules.
Analogy
Think of comparing flashlights by how strong the beam looks when pointed at you. Candlepower is that kind of comparison, using a standard light unit instead of a guess.
Intuition Check
Candlepower does not mean electrical power, like watts. It means the visible strength of the light in a given direction.
Example Sentence 1
The maintenance manual specified a 250-candlepower bulb for the landing light, so the mechanic confirmed the replacement matched before installing it.
Example Sentence 2
Check the beacon's candlepower rating during the preflight to confirm it meets night-flight requirements.