PARL —parallel PAT —pattern PATWAS —Pilots Automatic Telephone Weather Answering Service PAX —passenger PBCT —proposed boundary crossing time PBRF —pilot briefing PBX —private branch exchange PCA —positive control airspace PCL —pilot controlled lighting PCM —pulse code modulation PD —Pilot Deviation PDAR —preferential arrival and departure route PDC —pre-departure clearance; program designator code PDN —Public Data Network PDR —preferential departure route PERM —permanent/permanently PFC —passenger facility charge PGP —planning grant program PIC —principal interexchange carrier PIDP —programmable indicator data processor PIREP —pilot weather report PJE —parachute jumping exercise PLA —practice low approach PLW —plow/plowed PMS —program management system PNR —prior notice required POLIC —police station POP —point of presence POT —point of termination PPIMS —personal property information management system PPR —prior permission required PR —primary commercial service airport PREV —previous PRI —primary rate interface PRM —precision runway monitor PRN —pseudo random noise PROC —procedure PROP —propeller PSDN —public switched data network PSN —packet switched network PSR  —packed snow on runway(s) PSS —packet switched service PSTN —public switched telephone network PTC —presumed-to-conform PTCHY —patchy PTN —procedure turn PUB —publication PUP —principal user processor PVC —permanent virtual circuit PVD —plan view display PVT —private 

## R 

RAIL —runway alignment indicator lights RAMOS —remote automatic meteorological observing system RAPCO —radar approach control (USAF) RAPCON —radar approach control (FAA) RATCC —Radar Air Traffic Control Center RATCF —Radar Air Traffic Control Facility (USN) RBC —rotating beam ceilometer RBDPE —radar beacon data processing equipment RBSS —Radar Bomb Scoring Squadron RCAG —remote communications air/ground facility RCC —Rescue Coordination Center RCCC —Regional Communications Control Centers RCF —Remote Communication Facility RCIU — Remote Control Interface Unit RCL — runway centerline; radio communications link RCLL —runway centerline light system RCLR —RCL repeater RCLT —RCL terminal RCO —remote communications outlet RCU —remote control unit RDAT —digitized radar data RDP —radar data processing RDSIM —runway delay simulation model REC —receive/receiver REIL —runway end identifier lights RELCTD —relocated REP —report RF —radio frequency RL —General Aviation Reliever Airport RLLS —runway lead-in lights system RMCC —Remote Monitor Control Center RMCF —Remote Monitor Control Facility RML —radio microwave link RMLR —RML repeater RMLT —RML terminal RMM —remote maintenance monitoring RMMS —remote maintenance monitoring system RMNDR —remainder RMS —remote monitoring subsystem RMSC —remote monitoring subsystem concentrator RNAV —area navigation RNP —required navigation performance ROD —record of decision ROSA —report of service activity ROT —runway occupancy time RP —restoration priority RPC —restoration priority code RPG —radar processing group RPLC —replace 

