| 3LD | ICAO three-letter designator |
| AAM | Advanced air mobility |
| AAR | Adapted routes; Airport arrival rate |
| AAUP | Attention all users page |
| ABRR | Airborne reroute |
| AC | Advisory circular |
| ACDO | Air carrier district office |
| ACL | Aircraft list |
| ACLS | Automatic carrier landing system |
| ADAR | Adapted routes |
| ADF | Automatic direction finder |
| ADIZ | Land-based air defense identification zone |
| ADLY | Arrival delay |
| ADR | Adapted routes; Airport departure rate |
| ADS | Automatic dependent surveillance (ADS) [ICAO] |
| ADS-B | Automatic dependent surveillance-broadcast in (ADS |
| ADS-C | Automatic dependent surveillance-contract |
| ADW | Arrival/departure window |
| AFIS | Automatic flight information service |
| AFP | Airspace flow program |
| AHA | Aircraft hazard area |
| AIM | Aeronautical Information Manual |
| AIP | Aeronautical Information Publication (AIP) [ICAO] |
| AIRMET | Airmen's meteorological information |
| AIS | Aeronautical Information Services |
| AIT | Automated information transfer |
| ALD | Available landing distance |
| ALNOT | Alert notice |
| ALTITUDE | Cross (fix) at; above; below |
| ALTRV | Altitude reservation |
| AMVER | Automated mutual-assistance vessel rescue system |
| APB | Automated problem detection boundary |
| APD | Automated problem detection |
| APDIA | Automated problem detection inhibited area |
| APV | Approach with vertical guidance |
| ARO | Airport reservation office |
| ARP | Airport reference point |
| ARSR | Air route surveillance radar |
| ARTCC | Air route traffic control center |
| ASDA | Accelerate-stop distance available |
| ASDE | Airport surface detection equipment |
| ASLAR | Aircraft surge launch and recovery |
| ASR | Airport surveillance radar |
| ATC | Air traffic control |
| ATCAA | ATC assigned airspace |
| ATCRBS | Radar |
| ATCSCC | Air traffic control system command center |
| ATCT | Tower |
| ATD | Along-track distance |
| ATIS | Automatic terminal information service |
| ATO | Air traffic organization |
| ATPA | Automated terminal proximity alert |
| BVLOS | Beyond visual line of sight |
| CAO | Civil aircraft operation |
| CAS | Calibrated airspeed |
| CAT | Clear air turbulence |
| CBO | Community-based organization |
| CCF | Combined control facility |
| CEP | Central East Pacific |
| CFR | Call for release |
| CHA | Contingency hazard area |
| CLT | Calculated landing time |
| CMNPS | Canadian minimum navigation performance specification airspace |
| CNF | Computer navigation fix |
| COA | Certificate of waiver; authorization |
| CPDLC | Controller pilot data link communications |
| CSP | Constraint satisfaction point |
| CTA | Control area [ICAO]; Controlled time of arrival |
| CTAF | Common traffic advisory frequency |
| CTOP | Collaborative trajectory options program |
| CTRD | Certified tower radar display |
| DA | Decision altitude |
| DAS | Delay assignment |
| D-ATIS | Data link automatic terminal information service (D-ATIS) [ICAO]; Digital-automatic terminal information service |
| DCL | Departure clearance (DCL) application |
| DCT | Delay countdown timer |
| DEGREES | Fly heading |
| DH | Decision height |
| DME | Distance measuring equipment |
| DP | Instrument departure procedure |
| DRA | Debris response area |
| DSP | Departure sequencing program |
| DTAS | Digital terminal automation system |
| DVA | Diverse vector area |
| DVFR | Defense visual flight rules |
| DVRSN | Diversion |
| EAS | En route automation system |
| EDCT | Expect departure clearance time |
| EDST | En route decision support tool |
| EFC | Expect further clearance (time) |
| EFVS | Enhanced flight vision system |
| ELT | Emergency locator transmitter |
| E-MSAW | En route minimum safe altitude warning |
| eSRS | Enhanced special reporting service |
| EST | Estimated |
| ETA | Estimated time of arrival |
| ETE | Estimated time en route |
| FAF | Final approach fix |
| FIR | Flight information region |
| FIS-B | Flight information service-broadcast |
| FIX | Expect (altitude) at (time) or |
| FLIP | DoD FLIP |
| FMA | Final monitor aid |
| FMS | Flight management systems |
| FPA | Flight plan area |
| FRC | Request full route clearance |
| FRIA | FAA-recognized identification area |
| FSDO | Flight standards district office |
| FSPD | Freeze speed parameter |
| FSS | Flight service station |
| GBAS | Ground based augmentation system |
| GCA | Ground controlled approach |
| GCO | Ground communication outlet |
| GDP | Ground delay program |
| GLS | Ground based augmentation system (GBAS) landing system |
| GNE | Gross navigation error |
| GNSS | Global navigation satellite system |
| GPD | Graphic plan display |
| GPS | Global positioning system |
| GPS/WAAS | Unreliable |
| GS | Ground stop |
| HAA | Height above airport |
| HAL | Height above landing |
| HAT | Height above touchdown |
| HAZMAT | Hazardous materials |
| HF | High frequency |
| HRP | Heliport reference point |
| IAF | Initial approach fix |
| IAP | Instrument approach procedure |
| ICAO | International Civil Aviation Organization [ICAO] |
| IDAC | Integrated departure/arrival capability |
| IF | Intermediate fix |
| IFR | Instrument flight rules |
| ILS | Instrument landing system |
| IM | Inner marker |
| IMC | Instrument meteorological conditions |
| INREQ | Information request |
| INS | Inertial navigation system |
| IR | IFR military training routes |
| ISR | Increased separation required |
| LAA | Local airport advisory |
| LAANC | Low altitude authorization and notification capability |
| LAHSO | Land and hold short operations |
| LDA | Landing distance available [ICAO]; Localizer type directional aid |
| LF | Low frequency |
| LL | Lost link |
| LNAV | Lateral navigation |
| LOCATION | Numerous targets vicinity |
| LORAN | Long range navigation |
| LPV | Localizer performance with vertical guidance |
| LSA | Light-sport aircraft |
| LUAW | Line up and wait |
| MA | Monitor alert |
| MAA | Maximum authorized altitude |
| MANPADS | Man portable air defense systems |
| MAP | Missed approach point; Monitor alert parameter |
| MARSA | Military authority assumes responsibility for separation of aircraft |
| MCA | Minimum crossing altitude |
| MDA | Minimum descent altitude |
| MEA | Minimum en route IFR altitude |
| MEARTS | Micro-en route automated radar tracking system |
| MGOW | Maximum gross operating weight |
| MHA | Minimum holding altitude |
| MIA | Minimum IFR altitudes |
| MIS | Meteorological impact statement |
| MM | Middle marker |
| MOCA | Minimum obstruction clearance altitude |
| MRA | Minimum reception altitude |
| MRE | Meter reference element |
| MRP | Meter reference point list |
| MSA | Minimum safe altitude |
| MSAW | Minimum safe altitude warning |
| MTI | Moving target indicator |
| MTR | Military training routes |
| MVA | Minimum vectoring altitude |
| NAS | National Airspace System |
| NAVAID | Navigational aid |
| NAVSPEC | Navigation specification [ICAO] |
| NBCAP | National beacon code allocation plan airspace |
| NDB | Nondirectional beacon |
| NFDD | National flight data digest |
| NOPAC | North Pacific |
| NOTAM | Notice to Airmen |
| NOZ | Normal operating zone |
| NRP | North American route program |
| NRR | Non-restrictive routing |
| NRS | Navigation reference system |
| NTZ | No transgression zone |
| ODP | Obstacle departure procedure |
| OFT | Outer fix time |
| OM | Outer marker |
| OOP | Operations over people |
| OROCA | Off-route obstruction clearance altitude |
| OTR | Oceanic transition route |
| OTS | Organized track system |
| P-ACP | Prearranged coordination procedures |
| PAO | Public aircraft operation |
| PAR | Precision approach radar |
| PBCT | Proposed boundary crossing time |
| PBN | Performance-based navigation (PBN) [ICAO] |
| PDC | Pre-departure clearance |
| PDRR | Pre-departure reroute |
| PERTI | Plan, execute, review, train, improve |
| PGUI | Planview graphical user interface |
| PID | Pilot initiated downlink |
| PIREP | Pilot weather report |
| POFZ | Precision obstacle free zone |
| PPR | Prior permission required |
| PRM | Area navigation (RNAV); Precision runway monitor (PRM) system; PRM approach |
| PT | Procedure turn |
| PTP | Point-to-point |
| PTS | Polar track structure |
| PWS | Predictive wind shear alert system |
| RAD | Route amendment dialog |
| RAIM | Receiver autonomous integrity monitoring |
| RAIS | Remote airport information service |
| RC | Radio-controlled; Road reconnaissance |
| RCAG | Remote center air/ground facility |
| RCC | Rescue coordination center |
| RCO | Remote communications outlet |
| RCR | Runway condition reading |
| REL | Runway entrance lights |
| RHA | Refined hazard area |
| RID | Remote identification |
| RMI | Radio magnetic indicator |
| RNAV | Area navigation |
| RNP | Required navigation performance |
| RPIC | Remote pilot in command |
| RRIA | Reroute impact assessment |
| RSA | Runway safety area |
| RVFP | RNAV visual flight procedure |
| RwyCC | Runway condition codes |
| RwyCR | Runway condition report |
| SAA | Sense and avoid; Special activity airspace |
| SAR | Search and rescue |
| SATR | Special air traffic rules |
| SAW | Aviation watch notification message |
| SBA | Space-based ADS-B |
| SBAS | Satellite-based augmentation system |
| SECNOT | Security notice |
| SFA | Single frequency approach |
| SFO | Simulated flameout |
| SFRA | Special flight rules area |
| SGI | Special government interest |
| SID | Standard instrument departure |
| SIGMET | Significant meteorological information |
| SLDI | Sector list drop interval |
| SN | System strategic navigation |
| SOIA | Simultaneous offset instrument approach |
| STA | Scheduled time of arrival |
| STAR | Standard terminal arrival |
| STOL | Short takeoff and landing aircraft |
| sUAS | Small unmanned aircraft system |
| SWAP | Severe weather avoidance plan |
| SWSL | Supplemental weather service location |
| TAC | Trajectory altering clearance |
| TACAN | Tactical air navigation |
| TAS | Terminal automation systems |
| TAWS | Terrain awareness warning system |
| TBFM | Time-based flow management |
| TBM | Time-based management |
| TBO | Trajectory-based operations |
| TCAS | Traffic alert and collision avoidance system |
| TCH | Threshold crossing height |
| TDLS | Terminal data link system |
| TDZE | Touchdown zone elevation |
| TF | Terrain following |
| TFDM | Terminal flight data manager |
| TFR | Temporary flight restriction |
| TGUI | Timeline graphical user interface |
| THA | Transitional hazard area |
| THL | Takeoff hold lights |
| TIME | Clearance void if not off by; Delay indefinite (reason if known) expect further clearance; If no transmission received for |
| TIS-B | Traffic information service-broadcast |
| TMI | Traffic management initiative |
| TMPA | Traffic management program alert |
| TMU | Traffic management unit |
| TOC | Transfer of communication |
| TOD | Top of descent |
| TODA | Takeoff distance available [ICAO] |
| TOI | Track of interest |
| TORA | Takeoff run available [ICAO] |
| TOS | Trajectory options set |
| TRSA | Terminal radar service area |
| TRUST | The recreational UAS safety test |
| TSAS | Terminal sequencing and spacing |
| TSD | Traffic situation display |
| TVOR | Terminal-very high frequency omnidirectional range station |
| UA | Unmanned aircraft |
| UAM | Urban air mobility |
| UAP | Unidentified anomalous phenomena |
| UAS | Crewmember; Operator; Unmanned aircraft system |
| UASFM | UAS facility MAP |
| UHF | Ultrahigh frequency |
| U/S | Out of service/unserviceable |
| USAFIB | Army Aviation Flight Information Bulletin |
| UTM | UAS traffic management |
| VCOA | Visual climb over airport |
| VDP | Visual descent point |
| VFR | Visual flight rules |
| VHF | Very high frequency |
| VLF | Very low frequency |
| VLOS | Visual line of sight |
| VMC | Visual meteorological conditions |
| VNAV | Vertical navigation |
| VO | Visual observer |
| VOR | Very high frequency omnidirectional range station |
| VORTAC | VHF omnidirectional range/tactical air navigation |
| VOT | VOR test signal |
| VR | VFR military training routes |
| VSCS | Voice switching and control system |
| VTOL | Vertical takeoff and landing aircraft |
| WA | Airmen's meteorological information (AIRMET); Weather advisory |
| WAAS | Wide-area augmentation system |
| WAM | Wide area multilateration |
| WRA | Weather reconnaissance area |
| WS | SIGMET; Weather advisory |
| WST | Convective SIGMET; Weather advisory |
| XM | Coupled scheduling (CS)/ extended metering |