Aeronautical Terms beginning with R
RAA
Remote Airport Advisory
Radar
A device which, by measuring the time interval between transmission and reception of radio pulses and correlating the angular orientation of the radiated antenna beam or beams in azimuth and/or elevation, provides information on range, azimuth, and/or elevation of objects in the path of the transmitted pulses.
Radar Advisory
The provision of advice and information based on radar observations.
Radar Altimeter
Radio Altimeter.
Radar Approach
An instrument approach procedure which utilizes Precision Approach Radar (PAR) or Airport Surveillance Radar (ASR).
Radar Approach Control Facility
A terminal ATC facility that uses radar and nonradar capabilities to provide approach control services to aircraft arriving, departing, or transiting airspace controlled by the facility. a. Provides radar ATC services to aircraft operating in the vicinity of one or more civil and/or military airports in a terminal area. The facility may provide services of a ground controlled approach (GCA); i.e., ASR and PAR approaches. A radar approach control facility may be operated by FAA, USAF, US Army, USN, USMC, or jointly by FAA and a military service. Specific facility nomenclatures are used for administrative purposes only and are related to the physical location of the facility and the operating service generally as follows: 1. Army Radar Approach Control (ARAC) (Army). 2. Radar Air Traffic Control Facility (RATCF) (Navy/FAA). 3. Radar Approach Control (RAPCON) (Air Force/FAA). 4. Terminal Radar Approach Control (TRACON) (FAA). 5. Air Traffic Control Tower (ATCT) (FAA). (Only those towers delegated approach control authority.
Radar Approach [ICAO]
An approach, executed by an aircraft, under the direction of a radar controller.
Radar Arrival
An aircraft arriving at an airport served by a radar facility and in radar contact with the facility.
Radar Beacon
Radar.
Radar Clutter [ICAO]
The visual indication on a radar display of unwanted signals.
Radar Contact
A. Used by ATC to inform an aircraft that it is identified on the radar display and radar flight following will be provided until radar identification is terminated. Radar service may also be provided within the limits of necessity and capability. When a pilot is informed of “radar contact,” he/she automatically discontinues reporting over compulsory reporting points.
B. The term used to inform the controller that the aircraft is identified and approval is granted for the aircraft to enter the receiving controllers airspace.
Radar Contact Lost
Used by ATC to inform a pilot that radar data used to determine the aircraft’s position is no longer being received, or is no longer reliable and radar service is no longer being provided. The loss may be attributed to several factors including the aircraft merging with weather or ground clutter, the aircraft operating below radar line of sight coverage, the aircraft entering an area of poor radar return, failure of the aircraft transponder, or failure of the ground radar equipment.
Radar Contact [ICAO]
The situation which exists when the radar blip or radar position symbol of a particular aircraft is seen and identified on a radar display.
Radar Environment
An area in which radar service may be provided.
Radar Flight Following
The observation of the progress of radar identified aircraft, whose primary navigation is being provided by the pilot, wherein the controller retains and correlates the aircraft identity with the appropriate target or target symbol displayed on the radar scope.
Radar Identification
The process of ascertaining that an observed radar target is the radar return from a particular aircraft.
Radar Identification [ICAO]
The process of correlating a particular radar blip or radar position symbol with a specific aircraft.
Radar Identified Aircraft
An aircraft, the position of which has been correlated with an observed target or symbol on the radar display.
Radar Monitoring
Radar Service.
Radar Navigational Guidance
Radar Service.
Radar Point Out
An action taken by a controller to transfer the radar identification of an aircraft to another controller if the aircraft will or may enter the airspace or protected airspace of another controller and radio communications will not be transferred.
Radar Required
A term displayed on charts and approach plates and included in FDC NOTAMs to alert pilots that segments of either an instrument approach procedure or a route are not navigable because of either the absence or unusability of a NAVAID. The pilot can expect to be provided radar navigational guidance while transiting segments labeled with this term.
Radar Route
A flight path or route over which an aircraft is vectored. Navigational guidance and altitude assignments are provided by ATC.
Radar Separation
Radar Service.
Radar Service
A term which encompasses one or more of the following services based on the use of radar which can be provided by a controller to a pilot of a radar identified aircraft: Radar Monitoring, Radar Navigational Guidance, and Radar Separation.
Radar Service Terminated
Used by ATC to inform a pilot that he/she will no longer be provided any of the services that could be received while in radar contact. Radar service is automatically terminated, and the pilot is not advised in the following cases: a. An aircraft cancels its IFR flight plan, except within Class B airspace, Class C airspace, a TRSA, or where Basic Radar service is provided. 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 Service [ICAO]
Term used to indicate a service provided directly by means of radar. a. Monitoring The use of radar for the purpose of providing aircraft with information and advice relative to significant deviations from nominal flight path. b. Separation-The separation used when aircraft position information is derived from radar sources.
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.
Radar Traffic Information Service
Traffic Advisories.
Radar Vectoring [ICAO]
Provision of navigational guidance to aircraft in the form of specific headings, based on the use of radar.
Radar [ICAO]
A radio detection device which provides information on range, azimuth and/or elevation of objects. a. Primary Radar-Radar system which uses reflected radio signals. b. Secondary Radar-Radar system wherein a radio signal transmitted from a radar station initiates the transmission of a radio signal from another station.
Radial
A magnetic bearing extending from a VOR/VORTAC/TACAN navigation facility.
Radio
A device used for communication.
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
Nondirectional Beacon.
Radio Detection And Ranging
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.
RAIL
Runway Alignment Indicator Lights Sequenced Flashing Lights Which Are Installed Only In Combination With Other Light Systems
RAIS
Remote Airport Information Service.
Ramp
Apron. A defined area on an airport or heliport intended to accommodate aircraft for purposes of loading or unloading passengers or cargo, refueling, parking, or maintenance. With regard to seaplanes, a ramp is used for access to the apron from the water.
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
Road Reconnaissance
RCAG
Remote Communications Air/Ground Facility
RCC
Rescue Coordination Center
RCO
Remote Communications Outlet
RCR
Runway Condition Reading
Read Back
Repeat my message back to me.
Receiver Autonomous Integrity Monitoring (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
Receiving Controller.
Reconformance
The automated process of bringing an aircraft’s Current Plan Trajectory into conformance with its track.
Reduce Speed To (Speed)
Speed Adjustment.
REIL
Runway End Identifier Lights
Release Time
A departure time restriction issued to a pilot by ATC (either directly or through an authorized relay) 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 Airport Advisory (RAA)
A remote service which may be provided by facilities, which are not located on the landing airport, but have a discrete ground-to-air communication frequency or tower frequency when the tower is closed, automated weather reporting with voice available to the pilot at the landing airport, and a continuous ASOS/AWSS/AWOS data display, other direct reading instruments, or manual observation is available to the AFSS specialist.
Remote Airport Information Service (RAIS)
A temporary service provided by facilities, which are not located on the landing airport, but have communication capability and automated weather reporting available to the pilot at the landing airport.
Remote Communications Air/Ground Facility
An unmanned VHF/UHF transmitter/receiver facility which is used to expand ARTCC air/ground communications coverage and to facilitate direct contact between pilots and controllers. RCAG facilities are sometimes not equipped with emergency frequencies 121.5 MHz and 243.0 MHz.
Remote Communications Outlet
An unmanned communications facility remotely controlled by air traffic personnel. RCOs serve FSSs. RTRs serve terminal ATC facilities. An RCO or RTR may be UHF or VHF and will extend the communication range of the air traffic facility. There are several classes of RCOs and RTRs. 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 en route 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.
Remote Transmitter/Receiver
Remote Communications Outlet.
Report
Used to instruct pilots to advise ATC of specified information; e.g., “Report passing Hamilton VOR.”
Reporting Point
A geographical location in relation to which the position of an aircraft is reported.
Reporting Point [ICAO]
A specified geographical location in relation to which the position of an aircraft can be reported.
Request Full Route Clearance
Used by pilots to request that the entire route of flight be read verbatim in an ATC clearance. Such request should be made to preclude receiving an ATC clearance based on the original filed flight plan when a filed IFR flight plan has been revised by the pilot, company, or operations prior to departure.
Required Navigation Performance (RNP)
A statement of the navigational performance necessary for operation within a defined airspace. The following terms are commonly associated with RNP: Required Navigation Performance Level or Type (RNP-X), Required Navigation Performance (RNP) Airspace, Actual Navigation Performance (ANP), Estimated Position Error (EPE), Lateral Navigation (LNAV), and Vertical Navigation (VNAV).
Required Navigation Performance (RNP) Airspace
A generic term designating airspace, route (s), leg (s), operation (s), or procedure (s) where minimum required navigational performance (RNP) have been established.
Required Navigation Performance Level Or Type (RNP-X)
A value, in nautical miles (NM), from the intended horizontal position within which an aircraft would be at least 95-percent of the total flying time.
Rescue Co-Ordination Centre [ICAO]
A unit responsible for promoting efficient organization of search and rescue service and for coordinating the conduct of search and rescue operations within a search and rescue region.
Rescue Coordination Center
A search and rescue (SAR) facility equipped and manned to coordinate and control SAR operations in an area designated by the SAR plan. The U.S. Coast Guard and the U.S. Air Force have responsibility for the operation of RCCs.
Resolution Advisory
A display indication given to the pilot by the traffic alert and collision avoidance systems (TCAS II) recommending a maneuver to increase vertical separation relative to an intruding aircraft. Positive, negative, and vertical speed limit (VSL) advisories constitute the resolution advisories. A resolution advisory is also classified as corrective or preventive
Restricted Area
Airspace designated under 14 CFR Part 73, within which the flight of aircraft, while not wholly prohibited, is subject to restriction. Most restricted areas are designated joint use and IFR/VFR operations in the area may be authorized by the controlling ATC facility when it is not being utilized by the using agency. Restricted areas are depicted on en route charts. Where joint use is authorized, the name of the ATC controlling facility is also shown.
Restricted Area [ICAO]
An airspace of defined dimensions, above the land areas or territorial waters of a State, within which the flight of aircraft is restricted in accordance with certain specified conditions.
Resume Normal Speed
Used by ATC to advise a pilot that previously issued speed control restrictions are deleted. An instruction to “resume normal speed” does not delete speed restrictions that are applicable to published procedures of upcoming segments of flight, unless specifically stated by ATC. This does not relieve the pilot of those speed restrictions which are applicable to 14 CFR Section 91.117.
Resume Own Navigation
Used by ATC to advise a pilot to resume his/her own navigational responsibility. It is issued after completion of a radar vector or when radar contact is lost while the aircraft is being radar vectored.
Right Base Area
A type of Terminal Arrival Area. A 30NM arc centered on the left corner IAF (Initial Approach Fix). The area shares a boundary with the straight-in area except that it extends out for 30NM from the IAF and is bounded on the other side by a line extending from the IF through the FAF to the arc.
Rime Ice
Rough, milky, opaque ice formed by the instantaneous freezing of small supercooled water droplets.
RMI
Radio Magnetic Indicator
RNAV
Area Navigation (RNAV)
RNAV Approach
An instrument approach procedure which relies on aircraft area navigation equipment for navigational guidance.
RNAV Specification
A navigation specification based on area navigation that does not include the requirement for performance monitoring and alerting, designated by the prefix RNAV; e.g., RNAV 5, RNAV 1.
RNP Specification
A navigation specification based on area navigation that includes the requirement for performance monitoring and alerting, designated by the prefix RNP; e.g., RNP 4, RNP APCH.
Road Reconnaissance
Military activity requiring navigation along roads, railroads, and rivers. Reconnaissance route/route segments are seldom along a straight line and normally require a lateral route width of 10 NM to 30 NM and an altitude range of 500 feet to 10,000 feet AGL.
Roger
I have received all of your last transmission. It should not be used to answer a question requiring a yes or a no answer.
Rollout RVR
The RVR readout values obtained from RVR equipment located nearest the rollout end of the runway.
Route
A defined path, consisting of one or more courses in a horizontal plane, which aircraft traverse over the surface of the earth.
Route Action Notification
URET notification that a PAR/PDR/PDAR has been applied to the flight plan.
Route Segment
As used in Air Traffic Control, a part of a route that can be defined by two navigational fixes, two NAVAIDs, or a fix and a NAVAID.
Route Segment [ICAO]
A portion of a route to be flown, as defined by two consecutive significant points specified in a flight plan.
RSA
Runway Safety Area
RTR
Remote Transmitter/Receiver
Runway
A defined rectangular area on a land airport prepared for the landing and takeoff run of aircraft along its length. Runways are normally numbered in relation to their magnetic direction rounded off to the nearest 10 degrees; e.g., Runway 1, Runway 25.
Runway Centerline Lighting
Flush centerline lights spaced at 50-foot intervals beginning 75 feet from the landing threshold and extending to within 75 feet of the opposite end of the runway.
Runway Condition Reading
Numerical decelerometer readings relayed by air traffic controllers at USAF and certain civil bases for use by the pilot in determining runway braking action. These readings are routinely relayed only to USAF and Air National Guard Aircraft.
Runway End Identifier Lights (REIL)
Two synchronized flashing lights, one on each side of the runway threshold, which provide rapid and positive identification of the approach end of a particular runway.
Runway Gradient
The average slope, measured in percent, between two ends or points on a runway. Runway gradient is depicted on Government aerodrome sketches when total runway gradient exceeds 0.3%.
Runway Heading
The magnetic direction that corresponds with the runway centerline extended, not the painted runway number. When cleared to “fly or maintain runway heading,” pilots are expected to fly or maintain the heading that corresponds with the extended centerline of the departure runway. Drift correction shall not be applied; e.g., Runway 4, actual magnetic heading of the runway centerline 044, fly 044.
Runway In Use/Active Runway/Duty Runway
Any runway or runways currently being used for takeoff or landing. When multiple runways are used, they are all considered active runways. In the metering sense, a selectable adapted item which specifies the landing runway configuration or direction of traffic flow. The adapted optimum flight plan from each transition fix to the vertex is determined by the runway configuration for arrival metering processing purposes.
Runway Lights/Runway Edge Lights
Lights having a prescribed angle of emission used to define the lateral limits of a runway. Runway lights are uniformly spaced at intervals of approximately 200 feet, and the intensity may be controlled or preset.
Runway Markings
Airport Marking Aids. Markings used on runway and taxiway surfaces to identify a specific runway, a runway threshold, a centerline, a hold line, etc. A runway should be marked in accordance with its present usage such as: a. Visual. b. Nonprecision instrument. c. Precision instrument.
Runway OFZ
The runway OFZ (Obstacle Free Zone) is a defined volume of airspace centered above the runway. The runway OFZ is the airspace above a surface whose elevation at any point is the same as the elevation of the nearest point on the runway centerline. The runway OFZ extends 200 feet beyond each end of the runway. The width is as follows: 1. For runways serving large airplanes, the greater of: (a) 400 feet, or (b) 180 feet, plus the wingspan of the most demanding airplane, plus 20 feet per 1,000 feet of airport elevation. 2. For runways serving only small airplanes: (a) 300 feet for precision instrument runways. (b) 250 feet for other runways serving small airplanes with approach speeds of 50 knots, or more. (c) 120 feet for other runways serving small airplanes with approach speeds of less than 50 knots.
Runway Overrun
In military aviation exclusively, a stabilized or paved area beyond the end of a runway, of the same width as the runway plus shoulders, centered on the extended runway centerline.
Runway Profile Descent
An instrument flight rules (IFR) air traffic control arrival procedure to a runway published for pilot use in graphic and/or textual form and may be associated with a STAR. Runway Profile Descents provide routing and may depict crossing altitudes, speed restrictions, and headings to be flown from the en route structure to the point where the pilot will receive clearance for and execute an instrument approach procedure. A Runway Profile Descent may apply to more than one runway if so stated on the chart.
Runway Safety Area
A defined surface surrounding the runway prepared, or suitable, for reducing the risk of damage to airplanes in the event of an undershoot, overshoot, or excursion from the runway. The dimensions of the RSA vary and can be determined by using the criteria contained within AC 150/5300-13, Airport Design, Chapter 3. Figure 3-1 in AC 150/5300-13 depicts the RSA. The design standards dictate that the RSA shall be: a. Cleared, graded, and have no potentially hazardous ruts, humps, depressions, or other surface variations; b. Drained by grading or storm sewers to prevent water accumulation; c. Capable, under dry conditions, of supporting snow removal equipment, aircraft rescue and firefighting equipment, and the occasional passage of aircraft without causing structural damage to the aircraft; and, d. Free of objects, except for objects that need to be located in the runway safety area because of their function. These objects shall be constructed on low impact resistant supports (frangible mounted structures) to the lowest practical height with the frangible point no higher than 3 inches above grade.
Runway Transition
A. Conventional STARs/SIDs. The portion of a STAR/SID that serves a particular runway or runways at an airport.
B. RNAV STARs/SIDs. Defines a path(s) from the common route to the final point(s) on a STAR. For a SID, the common route that serves a particular runway or runways at an airport.
Runway Use Program
A noise abatement runway selection plan designed to enhance noise abatement efforts with regard to airport communities for arriving and departing aircraft. These plans are developed into runway use programs and apply to all turbojet aircraft 12,500 pounds or heavier; turbojet aircraft less than 12,500 pounds are included only if the airport proprietor determines that the aircraft creates a noise problem. Runway use programs are coordinated with FAA offices, and safety criteria used in these programs are developed by the Office of Flight Operations. Runway use programs are administered by the Air Traffic Service as “Formal” or “Informal” programs.
Runway Visibility Value
Visibility.
Runway Visibility Value (RVV)
The visibility determined for a particular runway by a transmissometer. A meter provides a continuous indication of the visibility (reported in miles or fractions of miles) for the runway. RVV is used in lieu of prevailing visibility in determining minimums for a particular runway.
Runway Visual Range
Visibility.
Runway Visual Range (RVR)
An instrumentally derived value, based on standard calibrations, that represents the horizontal distance a pilot will see down the runway from the approach end. It is based on the sighting of either high intensity runway lights or on the visual contrast of other targets whichever yields the greater visual range. RVR, in contrast to prevailing or runway visibility, is based on what a pilot in a moving aircraft should see looking down the runway. RVR is horizontal visual range, not slant visual range. It is based on the measurement of a transmissometer made near the touchdown point of the instrument runway and is reported in hundreds of feet. RVR is used in lieu of RVV and/or prevailing visibility in determining minimums for a particular runway.
Runway Visual Range [RVR] [ICAO]
The range over which the pilot of an aircraft on the centerline of a runway can see the runway surface markings or the lights delineating the runway or identifying its centerline.
Runway [ICAO]
A defined rectangular area on a land aerodrome prepared for the landing and take-off of aircraft.
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