A Notice to Airmen/Notice to Air Men/Notice to Airman/Notice to Air Missions (NOTAM) is a notice filed with an aviation authority to alert aircraft pilots of potential hazards along a flight route or at a location that could affect the flight. NOTAMs are notices or advisories that contain information concerning the establishment, conditions or change in any aeronautical facility, service, procedure or hazard, the timely knowledge of which may be essential to personnel and systems concerned with flight operations. NOTAMs are created and transmitted by government agencies and airport operators under guidelines specified by Annex 15: Aeronautical Information Services of the Convention on International Civil Aviation (CICA). The acronym NOTAM came into common use following the ratification of the CICA, which came into effect on 4 April 1947. Notices to airmen were normally published in a regular publication by each country's air authorities (e.g., in Flight International magazine in the UK). Several developments and amendments to the CICA have resulted in the more automated system available today. A NOTAM is filed with an aviation authority to alert aircraft pilots of any hazards en route or at a specific location. The authority, in turn, provides a means of disseminating relevant NOTAMs to pilots. Usage NOTAMs are issued (and reported) for several reasons, such as: hazards, including air shows, parachute jumps, kite flying, lasers, rocket launches, etc. flights by important people such as heads of state (which sometimes involve temporary flight restrictions, TFRs) closed runways inoperable radio navigational aids military exercises with resulting airspace restrictions inoperable lights on tall obstructions temporary erection of obstacles near airfields (e.g., cranes) passage of flocks of birds through airspace (a NOTAM in this category is known as a BIRDTAM) notifications of runway/taxiway/apron status concerning snow, ice, and standing water (a SNOWTAM) notification of an operationally significant change in volcanic ash or other dust contamination (an ASHTAM) software code risk announcements with associated patches to reduce specific vulnerabilities Aviation authorities typically exchange NOTAMs over Aeronautical Fixed Telecommunication Network (AFTN) circuits. Software allows pilots to identify NOTAMs near their intended route or at the intended destination. Some complain that the volume and increasing triviality of NOTAMs has reduced their usefulness. In the U.S. Air Force information technology enterprise, C4 NOTAMs (command, control, communications, and computer notices to airmen) are notices of new or updated Air Force Network Operating Instructions (AFNOIs). Often, these notices serve to direct Air Force