General (ICAO)

A NOTAM (Notice to Airmen) is, per ICAO Annex 15 §6.3, a notice distributed by means of telecommunication containing information concerning the establishment, condition or change in any aeronautical facility, service, procedure or hazard, the timely knowledge of which is essential to personnel concerned with flight operations.

Purpose: NOTAMs communicate short-notice, temporary or unplanned changes that, because of time criticality, cannot be promulgated in the AIP.

Triggers for issuing a NOTAM (Annex 15 §6.3.2):

Establishment or closure of aerodromes,
Commissioning/maintenance/failure of radio navigation aids,
Availability or change of flight procedures,
Activation of special-use airspace (P/R/D, ED-R, TRA),
Obstacles (cranes, temporary structures),
Runway or taxiway closures,
Unusual weather conditions (volcanic ash, radiation phenomena),
Special events with airspace impact.

Format: NOTAMs follow a standardised ICAO format with fields A (aerodrome/FIR), B (start UTC), C (end UTC or "PERM"), D (daily schedule), E (NOTAM plain text), F (lower limit), G (upper limit) and a 5-character Q-code for automatic classification.

Distribution (Annex 15 §6.3.5):

AFTN (Aeronautical Fixed Telecommunication Network) — primary distribution to all ATS units worldwide,
Pre-Flight Information Bulletins (PIB) for pilots,
Online NOTAM access via AIS web portals.

Classes:

NOTAM N: new information,
NOTAM R: replaces an earlier NOTAM,
NOTAM C: cancels an earlier NOTAM.

SNOWTAM: special format for runway condition with snow/ice/water (Annex 15 Appendix 2). ASHTAM: special format for volcanic ash (Annex 15 Appendix 3).

Europe (EASA / EU)

Application via Regulation (EU) 2017/373 Annex VI (Part-AIS). EU-wide harmonised digital NOTAM provision through the European AIS Database (EAD) managed by EUROCONTROL.

Germany (national)

Responsible: DFS Deutsche Flugsicherung (NOTAM Office in Frankfurt). NOTAMs for German airspace carry the location indicator EDxx in the Q-code.

Pre-flight information:

Online via the DFS AIS portal (free upon registration).
AFTN distribution to commercial aerodromes and ATC.
Pre-Flight Information Bulletin (PIB) on request.

Pilot obligation: Before every flight the PIC must review all relevant NOTAMs for the planned route — required by SERA.2010(b) (Pre-flight action) and Part-NCO.OP.135.