b..
An aircraft conducting an instrument, visual, or contact approach has landed or has been instructed to change to advisory frequency.

c.
An arriving VFR aircraft, receiving radar service to a tower‐controlled airport within Class B airspace, Class C airspace, a TRSA, or where sequencing service is provided, has landed; or to all

other airports, is instructed to change to tower or advisory frequency.
d..An aircraft completes a radar approach.
RADAR SURVEILLANCE- The radar observation of a given geographical area for the purpose of performing some radar function.
RADAR TRAFFIC ADVISORIES-Advisories issued to alert pilots to known or observed radar traffic which may affect the intended route of flight of their aircraft.
(See TRAFFIC ADVISORIES.)
RADAR TRAFFIC INFORMATION SERVICE-
(See TRAFFIC ADVISORIES.)
RADAR VECTORING [ICAO]-Provision of navigational guidance to aircraft in the form of specific headings, based on the use of radar.
RADIAL- A magnetic bearing extending from a VOR/VORTAC/TACAN navigation facility.
RADIO-
a..A device used for communication.
b..Used to refer to a flight service station; e.g., “Seattle Radio” is used to call Seattle FSS.
RADIO ALTIMETER- Aircraft equipment which makes use of the reflection of radio waves from the ground to determine the height of the aircraft above the surface.
RADIO BEACON-
(See NONDIRECTIONAL BEACON.)
RADIO DETECTION AND RANGING-
(See RADAR.)
RADIO MAGNETIC INDICATOR-An aircraft navigational instrument coupled with a gyro compass or similar compass that indicates the direction of a selected NAVAID and indicates bearing with respect to the heading of the aircraft.
RAIS-
(See REMOTE AIRPORT INFORMATION
SERVICE.)

RAMP-
(See APRON.)
RANDOM ALTITUDE- An altitude inappropriate for direction of flight and/or not in accordance with FAAO JO 7110.65, Para 4-5-1, VERTICAL SEPARATION MINIMA.

RANDOM ROUTE- Any route not established or charted/published or not otherwise available to all users.
RC-
(See ROAD RECONNAISSANCE.)
RCAG-
(See REMOTE COMMUNICATIONS
AIR/GROUND FACILITY.)

RCC-
(See RESCUE COORDINATION CENTER.)
RCO-
(See REMOTE COMMUNICATIONS OUTLET.)
RCR-
(See RUNWAY CONDITION READING.)
READ BACK-Repeat my message back to me.
RECEIVER AUTONOMOUS INTEGRITY MON-ITORING (RAIM)- A technique whereby a civil GNSS receiver/processor determines the integrity of the GNSS navigation signals without reference to sensors or non‐DoD integrity systems other than the receiver itself. This determination is achieved by a consistency check among redundant pseudorange measurements.
RECEIVING CONTROLLER- A controller/facility receiving control of an aircraft from another controller/facility.
RECEIVING FACILITY-
(See RECEIVING CONTROLLER.)