Definition
Coordinated Universal Time (UTC) is the global standard time reference used in aviation. It is the time at the Prime Meridian (0° longitude, running through Greenwich, England) and does not change for time zones or daylight saving. All flight plans, weather reports, NOTAMs, and ATC clearances use UTC so that pilots and controllers anywhere in the world are working from the same clock.
Plain English
A single worldwide clock that everyone in aviation uses, so there's no confusion between time zones. It's the time at Greenwich, England, and it never shifts for daylight saving.
Context Anchor
Pilots see Coordinated Universal Time in flight planning, aviation weather, training records, aircraft logs, and other records where local time zones could cause confusion.
Derivation
Coordinated' because it's agreed and synchronized internationally. 'Universal' because it applies everywhere on Earth, not just one region. The order of letters (UTC) is a compromise between English and French wording, which is why the abbreviation doesn't match the English phrase order.
Why Pilots Care
A single shared time reference prevents confusion on international routes, ensures accurate flight planning, and keeps all logs and ATC clearances aligned.
Grounding Statement
If two people in different countries both say 1800 Coordinated Universal Time, they are talking about the same exact moment.
Intuition Check
Do not read “Coordinated” as simply meaning “well organized.” Here it means the time standard is kept aligned internationally. Do not read “Universal” as local time everywhere; it is one shared world reference time.
Example Sentence 1
The METAR was issued at 1755Z, which the pilot converted to local time before checking weather trends.
Example Sentence 2
All entries on the FAA flight plan form must list times in Coordinated Universal Time.