AIM 8/15/19  7/16/20  6. Status of navigational aids, ILSs, or radar service availability. 7. Other information essential to planned en route, terminal, or landing operations. c. Pilots should ensure they review those NO- TAMs contained under the ARTCC location (for example, ZDC, ZOB, etc.) that the flight is operating within as they can include NOTAMs relevant to all operations, including Central Altitude Reservation Function (CARF), Special Use Airspace (SUA), Temporary Flight Restrictions (TFR), Global Posi- tioning System (GPS), Flight Data Center (FDC) changes to routes, wind turbine, and Unmanned Aircraft System (UAS).  NOTAM information is transmitted using ICAO contrac- tions to reduce transmission time. See TBL 5 − 1 − 2 for a listing of the most commonly used contractions, or go online to the following URL:  https://www.notams.faa.gov/ downloads/contractions.pdf . For a complete listing of approved NOTAM Contractions, see FAA JO Order 7340.2, Contractions. d. Due to the changeable nature of the NAS components, and frequent processing of NOTAM information, it is recommended, that while en route, pilots contact ATC or FSS and obtain updated information for their route of flight and destination. Pilots should be particularly vigilant when operating at locations without an operating control tower. Dynamic situations, such as snow removal, fire and rescue activities, construction, and wildlife encroach- ment, may pose hazards that may not reach the pilot prior to arrival/departure. e. If a NAVAID fails or is removed from service prior to all airspace and procedural dependencies being removed, a NOTAM is published to inform pilots of the NAVAID being Unserviceable (U/S). Pilots must check NOTAMs to ensure any NAVAID required for the flight is in service. There can be considerable time between the NAVAID being U/S and ultimately its removal from the charts, which, during the transition period, means a NOTAM is the primary method of alerting pilots to its unavailability. It is recommended that pilots using VFR charts should regularly consult the Aeronautical Chart Bulletin found in the back matter of the appropriate Chart Supplement U.S. This bulletin identifies any updates to the chart that have not yet been accounted 2. FDC NOTAMs.  On those occasions when it becomes necessary to disseminate information that is regulatory in nature, an FDC NOTAM is issued. FDC NOTAMs include NOTAMs such as: (e) Pointer NOTAMs. NOTAMs issued to point to additional aeronautical information. When pointing to another NOTAM, the keyword in the pointer NOTAM must match the keyword in the original NOTAM. Pointer NOTAMs should be issued for, but are not limited to, TFRs, Airshows, Temporary SUA, major NAS system interruptions, etc. (d) Communication and services. (c) Visual and radio navigational aids. (b) Airspace to include CARF, SUA, and general airspace activity like UAS or pyrotechnics. (a) Aerodrome activity and conditions, to include field conditions. 1. NOTAM (D)  information is disseminated for all navigational facilities that are part of the National Airspace System (NAS), all public use aerodromes, seaplane bases, and heliports listed in the Chart Supplement U.S. NOTAM (D) information includes such data as taxiway closures, personnel and equip- ment near or crossing runways, and airport lighting aids that do not affect instrument approach criteria, such as VASI. All NOTAM Ds must have one of the keywords listed in TBL 5 − 1 − 1, as the first part of the text after the location identifier. These keywords categorize NOTAM Ds by subject; for example, APRON (ramp), RWY (runway), SVC (Services), etc. There are several types of NOTAM Ds: f. NOTAM information is classified as Domestic NOTAMs (NOTAM D), Flight Data Center (FDC) NOTAMs, International NOTAMs, or Military NOTAMs. 2. Charts may indicate a NAVAID’s unavailability by depicting a crosshatch pattern through the frequency, which indicates its shutdown status. 1. Pilots should be alert for NAVAIDs having a dissimilar identifier from the airport(s) they serve and to use the Chart Supplement U.S. to identify the correct NAVAID NOTAM file. Flight planning should include review of NAVAIDs that aren’t included for the departure/destination airport but may be part of the route of flight. for because of the extended six − month chart cycle for most VFR charts. NOTE − NOTE − 5 − 1 − 3 Preflight