When does night start for logging? Civil twilight explained
Checked against the sources below on 29 October 2026. How these guides are written
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For logging, night runs from the end of evening civil twilight to the beginning of morning civil twilight: the moments the centre of the sun is 6 degrees below the horizon (14 CFR 1.1, SERA Article 2(97), the CASR Dictionary). How long after sunset that comes depends on latitude and season: 20 to 23 minutes at Singapore all year, 47 minutes at London in late June, almost 2 hours at Oslo in late June, and never at Anchorage from about 8 June to 4 July 2026.
- FAA night
- End of evening civil twilight to beginning of morning civil twilight, "as published in the Air Almanac"
- Every night
- 14 CFR 1.1
- EASA night
- Same, with civil twilight at the sun's centre 6 degrees below the horizon
- Every night
- SERA Art 2(97); FCL.010
- CASA night
- End of evening civil twilight to beginning of the following morning civil twilight
- Every night
- CASR Dictionary
- Civil twilight
- Centre of the sun geometrically 6 degrees below the horizon
- Morning and evening
- USNO definitions
- Sunrise and sunset
- Centre of the sun 50 arcminutes below the horizon (16' radius plus 34' refraction)
- Morning and evening
- USNO definitions
- FAA night passenger currency
- 3 takeoffs and 3 full-stop landings, 1 h after sunset to 1 h before sunrise
- Preceding 90 days
- 14 CFR 61.57(b)
- CASA night passenger recency
- 3 takeoffs and 3 landings at night, same category
- Previous 90 days
- CASR 61.395(2)
What counts as night for logging?
All three authorities define night by civil twilight. 14 CFR 1.1: night "means the time between the end of evening civil twilight and the beginning of morning civil twilight, as published in the Air Almanac, converted to local time". The CASR Dictionary: "the period between the end of evening civil twilight and the beginning of the following morning civil twilight". SERA Article 2(97) adds the angle: "Civil twilight ends in the evening when the centre of the sun's disc is 6 degrees below the horizon and begins in the morning when the centre of the sun's disc is 6 degrees below the horizon".
Part-FCL's own definition in FCL.010 adds "or such other period between sunset and sunrise as may be prescribed by the appropriate authority", so an EASA state may set a different period. The US Naval Observatory defines sunset as the sun's centre 50 arcminutes below the horizon and civil twilight as the centre 6 degrees below. Civil twilight itself counts as day in your logbook.
Night time is the part of your flight time that falls inside that window. A takeoff or landing logged as night is one made inside it. FAA passenger currency is narrower: 61.57(b) counts only takeoffs and full-stop landings made "during the period beginning 1 hour after sunset and ending 1 hour before sunrise". CASA 61.395(2) and EASA FCL.060(b)(2) say "at night", which takes the civil twilight definition.
Why does civil twilight last longer at high latitudes?
Near the equator the sun drops almost straight down, so it covers the 6 degrees below the horizon in about 20 minutes. At high latitudes it sinks at a shallow angle and slides along the horizon. US Naval Observatory times for 2026 show the time from sunset to the end of civil twilight on 21 June, 21 December and 20 March: Singapore 22, 23 and 20 minutes; Darwin 23, 23 and 22; Hobart 33, 35 and 29; New York 34, 31 and 28; London 47, 40 and 33; Oslo 113, 58 and 42.
Summer stretches it further. At Oslo Gardermoen on 21 June 2026 the sun sets at 20:46 UTC, civil twilight ends at 22:39 UTC and starts again at 23:56 UTC, so the night lasts 77 minutes. At Anchorage the sun stays within 6 degrees of the horizon all night from about 8 June to 4 July 2026, so no flight there logs any night, even at local midnight. On 21 June neither Tromsø nor Longyearbyen on Svalbard has any night at all.
Winter turns it around. At Tromsø on 21 December 2026 the sun never rises, yet civil twilight runs from 08:32 to 12:53 UTC, so a flight in that window logs 4 hours 21 minutes of day without seeing the sun. At Longyearbyen the sun stays more than 6 degrees below the horizon all day, and every minute is night.
Worked examples: one landing, three rules
London Heathrow, 21 December 2026: sunset 15:55 UTC, end of civil twilight 16:35 UTC. A circuit session with Out at 15:50 and In at 17:05 UTC logs 1:15 in total, of which 0:45 is day and 0:30 is night. Every landing at or after 16:35 is a night landing in your logbook and counts toward CASA 61.395(2) and EASA FCL.060(b)(2) night recency. For FAA 61.57(b) only full-stop landings at or after 16:55 UTC, sunset plus 1 hour, count.
Darwin, 21 June 2026: sunset 09:00 UTC (18:30 local), end of civil twilight 09:23 UTC (18:53 local). A landing at 18:55 local, 25 minutes after sunset, is already a night landing for the logbook. In London in late June a landing 25 minutes after sunset would still be day.
Oslo Gardermoen, 21 June 2026: a landing at 22:30 UTC, half past midnight local time, is a day landing, because civil twilight does not end until 22:39 UTC, and that night lasts only until 23:56 UTC, when morning civil twilight begins.
How do logbook apps work out night from airport coordinates?
From the two airports' coordinates and your Out and In times, an app estimates where the aircraft is at each moment, for example along the great circle between the airports at an even pace, works out the sun's elevation at each point with a solar position method such as NOAA's, and counts the minutes when the sun's centre is more than 6 degrees below the horizon.
The definitions say nothing about aircraft altitude, so the elevation is worked out for the ground position below the aircraft. On a long sector at high latitude the route matters, because the aircraft can fly into and out of night.
Most wrong night totals come from wrong inputs: local times entered where the app expects UTC, a missing or wrong airport code, or a route that departs far from the great circle. To check a sector, look up civil twilight for both airports in the US Naval Observatory's one-day tool and compare it with your Off and On times.
Mistakes pilots make
- Starting night at sunset. Logged night starts at the end of evening civil twilight, 20 minutes to 2 hours later depending on latitude and season.
- Assuming twilight lasts about 30 minutes everywhere. It ran 22 minutes at Singapore and 113 minutes at Oslo on 21 June 2026.
- Counting dusk landings toward FAA night passenger currency. 61.57(b) needs full-stop landings after sunset plus 1 hour, later than logged night.
- Entering local times where the app expects UTC. The night split moves by the time zone offset, and so does every night landing.
What Off Chocks tracks
- Off Chocks works out night by walking each flight's great-circle route every 5 minutes with the NOAA solar position and finding each crossing of 6 degrees below the horizon to within about 10 seconds. Night is truncated to the whole minute.
- A landing is classed as night when the sun is more than 6 degrees below the horizon at the arrival airport at the On time, and a takeoff as night when the same holds at the departure airport at the Off time. Tap the Night row in the form to see first and last light at both airports in local time.
- FAA 61.57(b) currency uses its own sunset plus 1 hour window, with sunset at the sun's centre 0.833 degrees below the horizon.
- If your operator or authority needs a different figure, turn on Set day and night by hand for that flight.
Common questions
- Is night for logging the same as night for currency?
- Under CASA and EASA rules, yes: 61.395(2) and FCL.060(b)(2) say "at night", which uses civil twilight unless your EASA state prescribes another period. Under FAA rules, no: 61.57(b) uses 1 hour after sunset to 1 hour before sunrise, and the landings must be to a full stop.
- How long after sunset does civil twilight end?
- In 2026, 20 to 23 minutes at Singapore and Darwin, 28 to 47 minutes between New York and London depending on season, and close to 2 hours at Oslo in late June. North of about 60.5 degrees around the June solstice it does not end at all.
- Does a landing during civil twilight count as a night landing?
- No. Civil twilight is part of the day for logging. A landing counts as night once evening civil twilight has ended.
- Do I log any night if the sun never gets 6 degrees below the horizon?
- No. If civil twilight never ends, as at Anchorage from about 8 June to 4 July 2026, there is no logbook night that day.
- Does flying high change when night starts for logging?
- The FAA, EASA and CASA definitions do not adjust for altitude. Night is worked out from the sun's position relative to the horizon, in practice for the ground below the aircraft.
Sources
- 14 CFR 1.1 General definitions: night (eCFR, up to date as of 27 Oct 2026)
- 14 CFR 61.57 Recent flight experience: Pilot in command (eCFR)
- EASA Easy Access Rules for Standardised European Rules of the Air (SERA), Article 2(97)
- Civil Aviation Safety Regulations 1998, Compilation No. 103: Dictionary and 61.395
- US Naval Observatory: Rise, Set, and Twilight Definitions
- US Naval Observatory: Sun and Moon Data for One Day (source of the 2026 times)
This is a plain-words summary to help you keep your own records, not legal advice. The regulation and your operator's procedures always take precedence.