Definition
The period between the beginning of morning civil twilight and the end of evening civil twilight, during which natural light from the sun is sufficient for normal outdoor visual activity without artificial illumination. For aviation regulatory purposes, daylight is defined by the position of the sun relative to the horizon and is used to establish when day and night flight rules apply.
Plain English
The hours when there is enough natural sunlight outside to see clearly without needing lights. In flying, it marks when the rules for day operations apply rather than the rules for night operations.
Context Anchor
Seen in flight planning, airport lighting, aircraft lighting, and day-versus-night operating discussions.
Derivation
From Old English 'daeg' (day) and 'leoht' (light) — literally 'the light of the day.' Useful here because the regulatory meaning still rests on that simple idea: there is enough sunlight to see by.
Why Pilots Care
Determines if position lights are required and whether day or night currency applies.
Intuition Check
Do not assume daylight means only the time after sunrise and before sunset. In aviation, daylight can include the usable light during civil twilight before sunrise and after sunset.
Example Sentence 1
The flight was planned to arrive well before the end of daylight so the pilot would not need to meet night currency requirements.
Example Sentence 2
Aircraft position lights are not required while operating in daylight.