RADIO BEACON (P/CG) - (See Non-Directional Beacon)
RADIO BEACON (JCS, NATO) - A radio transmitter which emits a distinctive or characteristic signal used for the determination of bearings, courses, or location.
RADIO MAGNETIC INDICATOR/RMI (P/CG) - An aircraft navigational instrument coupled with a gyro compass or similar compass that indicates the direction of a selected navigational aid and indicates bearing with respect to the heading of the aircraft.
RADIO MAGNETIC INDICATOR (JCS, NATO) - An instrument which displays aircraft heading and bearing to selected radio navigation aids.
RAMP - (See Apron)
RAPID - Used in Meteorological messages (See Landing Forecast Trend type).
RAPID EXIT TAXIWAY INDICATOR LIGHTS - (See Airport Lighting)
READBACK (P/CG) - Repeat my message back to me.
READBACK (ICAO) - A procedure whereby the receiving station repeats a received message or an appropriate part thereof back to the transmitting station so as to obtain confirmation of correct reception.
RECEIVING CONTROLLER/FACILITY - A controller/facility receiving control of an aircraft from another controller/facility.
RECEIVING UNIT/CONTROLLER (ICAO) - Air Traffic Services unit/Air Traffic Controller to which a message is sent.
REDUCE SPEED TO (SPEED) - (See Speed Adjustment)
RELEASE TIME (P/CG) - A departure time restriction issued to a pilot by Air Traffic Control when necessary to separate a departing aircraft from other traffic.
RELEASE TIME (ICAO) - Time prior to which an aircraft should be given further clearance or prior to which it should not proceed in case of radio failure.
REMOTE COMMUNICATION AIR/GROUND FACILITY/RCAG - An unmanned Very High Frequency/Ultra High Frequency transmitter/receiver facility which is used to expand Air Route Traffic Center air/ground communications coverage and to facilitate direct contact between pilots and controllers. RCAG facilities are sometimes not equipped with emergency frequencies
121.5 megahertz and 243.0 megahertz.
REMOTE COMMUNICATION OUTLET/RCO AND REMOTE TRANSMITTER/RECEIVER/RTR - An unmanned communications facility remotely controlled by air traffic personnel, RCO's serve Flight Service Station's. RTR's serve terminal Air Traffic Control facilities. An RCO or RTR may be Ultra High Frequency or Very High Frequency and will extend the communication range of the air traffic facility. There are several classes of RCO's and RTR's. The class is determined by the number of transmitters or receivers. Classes A through G are used primarily for air/ground purposes. RCO and RTR class O facilities are nonprotected outlets subject to undetected and prolonged outages. RCO (O)'s and RTR (O)'s were established for the express purpose of providing ground-to-ground communications between Air Traffic Control specialists and pilots located at a satellite airport for delivering enroute clearances, issuing departure authorizations, and acknowledging Instrument Flight Rules cancellations or departure/landing times. As a secondary function, they may be used for advisory purposes whenever the aircraft is below the coverage of the primary air/ground frequency.