background image Abbreviation/ Acronym Meaning RA Resolution Advisory RAA . Remote Advisory Airport RAIM Receiver Autonomous Integrity Monitoring RAIS Remote Airport Information Service RBDT Ribbon Display Terminals RC Radio - Controlled RCAG . Remote Center Air/Ground RCC . Rescue Coordination Center RCLS Runway Centerline Lighting System RCO . Remote Communications Outlet RID Remote Identification RPIC . Remote Pilot - in - Command TAF . Aerodrome Forecast RD Rotor Diameter REIL . Runway End Identifier Lights REL . Runway Entrance Lights RFM . Rotorcraft Flight Manual RLIM Runway Light Intensity Monitor RMI . Radio Magnetic Indicator RNAV Area Navigation RNP . Required Navigation Performance ROC . Required Obstacle Clearance RPAT RNP Parallel Approach Runway Transitions RVR . Runway Visual Range RVSM Reduced Vertical Separation Minimum RWSL Runway Status Light SAA . Sense and Avoid SAFO Safety Alerts For Operators SAM . System Area Monitor SAR . Search and Rescue SAS . Stability Augmentation System SATR Special Air Traffic Rules SBAS Satellite - based Augmentation System SDF . Simplified Directional Facility SFL Sequenced Flashing Lights SFR . Special Flight Rules SFRA Special Flight Rules Area SGI Special Government Interest SIAP . Standard Instrument Approach Procedure SID Standard Instrument Departure SIGMET Significant Meteorological Information SM Statute Mile SMGCS Surface Movement Guidance Control System SNR . Signal - to - noise Ratio SOIA Simultaneous Offset Instrument Approaches Abbreviation/ Acronym Meaning SOP . Standard Operating Procedure SPC . Storm Prediction Center SPS Standard Positioning Service STAR Standard Terminal Arrival STARS . Standard Terminal Automation Replacement System STMP Special Traffic Management Program sUAS Small UAS TA . Traffic Advisory TAA . Terminal Arrival Area TAC . Terminal Area Chart TACAN Tactical Air Navigation TAS . True Air Speed TCAS Traffic Alert and Collision Avoidance System TCH . Threshold Crossing Height TD Time Difference TDLS Tower Data Link System TDWR . Terminal Doppler Weather Radar TDZ . Touchdown Zone TDZE Touchdown Zone Elevation TDZL Touchdown Zone Lights TEC . Tower En Route Control THL . Takeoff Hold Lights TIS Traffic Information Service TIS - B Traffic Information Service - Broadcast TLS . Transponder Landing System TPP Terminal Procedures Publications TRSA Terminal Radar Service Area TRUST . The Recreational UAS Safety Test TSO . Technical Standard Order TWIB Terminal Weather Information for Pilots System U.S. . United States UA Unmanned Aircraft UAM Urban Air Mobility UAS . Unmanned Aircraft System UASFM UAS Facility Map UAV . Unmanned Aerial Vehicle UFO . Unidentified Flying Object UHF . Ultrahigh Frequency USCG United States Coast Guard UTC . Coordinated Universal Time UTM . UAS Traffic Management UWS . Urgent Weather SIGMET UWS . Urgent Weather SIGMET VAR . Volcanic Activity Reporting Appendix 3 - Abbreviations/Acronyms