Plain English Meaning

Zulu is the one shared clock that aviation uses worldwide, so everyone -- pilots, controllers, and weather forecasters -- is talking about the same moment in time, no matter what time zone they are in.

Full Definition

Zulu is the aviation term for Coordinated Universal Time (UTC), the single worldwide time standard used in flight planning, weather products, NOTAMs, flight plans, and ATC communications. It is the same clock everywhere on Earth and does not change for time zones or daylight saving time. Times are written with a trailing 'Z' (for example, 1430Z) and expressed in a 24-hour format.

Context Anchor

Seen in preflight weather briefings and products as “.”