NOTAM — Notice to Airmen

NOTAM — Notice to Airmen

NOTAMs are the official mechanism through which changes to the operational aviation environment are communicated to flight crews and dispatchers. They are mandatory reading before any flight and can directly affect routing, alternate planning and departure feasibility.

NOTAM Categories

NOTAMs cover a wide range of topics: runway, taxiway and apron closures or restrictions; navigational aid (VOR, ILS, NDB) outages or limitations; airspace restrictions — temporary restricted areas (TRAs), military exercises, VIP movements; obstacle warnings — construction cranes, new structures near airports; procedure changes — instrument approach, departure and arrival procedure amendments; aerodrome operating hours changes.

NOTAM Format

NOTAMs follow a standardised ICAO format with defined fields: Q-code (subject and condition), location (ICAO code or FIR), validity period (from/to in UTC), lower/upper limits, and the full text of the notice.

Distribution

NOTAMs are issued by designated national NOTAM offices (NOF) and distributed through the ICAO NOTAM system. Pilots and dispatchers access NOTAMs through pre-flight briefing systems. Many airlines integrate NOTAM data into their Operations Control Centre (OCC) systems.

SNOWTAM and ASHTAM

Specialised NOTAM formats include SNOWTAM (runway surface conditions — contamination, braking action) and ASHTAM (volcanic ash — critical for routing around ash clouds).