topA/C - AircraftA/G - Air to GroundA/H - Altitude/HeightAAC - Mike Monroney Aeronautical CenterAAF - Army Air FieldAAI - Arrival Aircraft IntervalAAP - Advanced Automation ProgramAAR - Airport Acceptance RateABDIS - Automated Data Interchange System Service BACAIS - Air Carrier Activity Information SystemACAS - Aircraft Collision Avoidance SystemACC - Airports Consultants CouncilACC - Area Control CenterACCT - Accounting RecordsACD - Automatic Call DistributorACDO - Air Carrier District OfficeACF - Area Control FacilityACFO - Aircraft Certification Field OfficeACFT - AircraftACI-NA - Airports Council International - North AmericaACID - Aircraft IdentificationACIP - Airport Capital Improvement PlanACLS - Automatic Carrier Landing SystemACLT - Actual Landing Time CalculatedACO - Office of Airports Compliance and Field OperationsACO - Aircraft Certification OfficeACRP - Airport Cooperative Research ProgramADA - Air Defense AreaADAP - Airport Development Aid ProgramADAS - AWOS Data Acquisition SystemADCCP - Advanced Data Communications Control ProcedureADDA - Administrative DataADF - Automatic Direction FindingADI - Automatic De-Ice and InhibitorADIN - AUTODIN ServiceADIZ - Air Defense Identification ZoneADL - Aeronautical Data-LinkADLY - Arrival DelayADO - Airline Dispatch OfficeADP - Automated Data ProcessingADS - Automatic Dependent SurveillanceADSIM - Airfield Delay Simulation ModelADSY - Administrative Equipment SystemsADTN - Administrative Data Transmission NetworkADTN2000 - Administrative Data Transmission Network 2000ADVO - Administrative VoiceAEG - Aircraft Evaluation GroupAERA - Automated En-Route Air Traffic ControlAEX - Automated ExecutionAF - Airway FacilitiesAFB - Air Force BaseAFIS - Automated Flight Inspection SystemAFP - Area Flight PlanAFRES - Air Force Reserve StationAFS - Airways Facilities SectorAFSFO - AFS Field OfficeAFSFU - AFS Field UnitAFSOU - AFS Field Office Unit (Standard is AFSFOU)AFSS - Automated Flight Service StationAFTN - Automated Fixed Telecommunications NetworkAGIS - Airports Geographic Information SystemAGL - Above Ground LevelAID - Airport Information DeskAIG - Airbus Industries GroupAIM - Airmans Information ManualAIP - Airport Improvement PlanAIRMET - Airmens Meteorological InformationAIRNET - Airport Network Simulation ModelAIS - Aeronautical Information ServiceAIT - Automated Information TransferALP - Airport Layout PlanALS - Approach Lighting SystemALSF1 - ALS with Sequenced Flashers IALSF2 - ALS with Sequenced Flashers IIALSIP - Approach Lighting System Improvement PlanALTRV - Altitude ReservationAMASS - Airport Movement Area Safety SystemAMCC - ACF/ARTCC Maintenance Control CenterAMOS - Automated Meteorological Observation StationAMP - ARINC Message Processor (OR) Airport Master Plan AMVER - Automated Mutual Assistance Vessel Rescue System ANC - Alternate Network ConnectivityANCA - Airport Noise and Capacity ActANG - Air National GuardANGB - Air National Guard BaseANMS - Automated Network Monitoring SystemANSI - American National Standards GroupAOA - Air Operations AreaAP - Acquisition PlanAPP - ApproachAPS - Airport Planning StandardAQAFO - Aeronautical Quality Assurance Field OfficeARAC - Army Radar Approach Control (AAF)ARAC - Aviation Rulemaking Advisory CommitteeARCTR - FAA Aeronautical Center or AcademyARF - Airport Reservation FunctionARFF - Aircraft Rescue and Fire FightingARINC - Aeronautical Radio, Inc.ARLNO - Airline OfficeARO - Airport Reservation OfficeARP - Airport Reference PointARRA - American Recovery and Reinvestment Act of 2009ARSA - Airport Service Radar AreaARSR - Air Route Surveillance RadarARTCC - Air Route Traffic Control CenterARTS - Automated Radar Terminal SystemASAS - Aviation Safety Analysis SystemASC - AUTODIN Switching CenterASCP - Aviation System Capacity PlanASD - Aircraft Situation DisplayASDA - Accelerate - Stop Distance AvailableASLAR - Aircraft Surge Launch And RecoveryASM - Available Seat MileASP - Arrival Sequencing ProgramASOS - Automatic Surface Observation SystemASQP - Airline Service Quality PerformanceASR - Airport Surveillance RadarASTA - Airport Surface Traffic AutomationASV - Airline Schedule VendorAT - Air TrafficATA - Air Transport Association of AmericaATAS - Airspace and Traffic Advisory ServiceATCAA - Air Traffic Control Assigned AirspaceAT&T - American Telephone and TelegraphAT&T ASDC - AT&T Agency Service Delivery CenterAT&T CSA - AT&T Customer Support AssociateATC - Air Traffic ControlATCBI - Air Traffic Control Beacon IndicatorATCCC - Air Traffic Control Command CenterATCO - Air Taxi Commercial OperatorATCRB - Air Traffic Con