Aeronautical Terms beginning with R

RA

Resolution Advisory,Radio Altitude

RA

Resolution Advisory

RAA

Remote Advisory Airport

Rabbit, the

High-intensity flasher system installed at many large airports. The flashers consist of a series of brilliant blue-white bursts of light flashing in sequence along the approach lights, giving the effect of a ball of light traveling towards the runway.

Radar

Radio Detection And Ranging.

Radar

A system that uses electromagnetic waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, weather formations, and terrain. The term RADAR was coined in 1941 as an acronym for Radio Detection and Ranging. The term has since entered the English language as a standard word, radar, losing the capitalization in the process.

RADAR (contraction for radio detection and ranging)

An electronic instrument used for the detection and ranging of distant objects of such composition that they scatter or reflect radio energy. Since hydrometeors can scatter radio energy, weather radars, operating on certain frequency bands, can detect the presence of precipitation, clouds, or both.

Radar altitude

The altitude of an aircraft determined by radar-type radio altimeter; thus the actual distance from the nearest terrain or water feature encompassed by the downward directed radar beam. For all practical purposes, it is the“actual” distance above a ground or inland water surface or the true altitude above an ocean surface.

Radar approach

The controller provides vectors while monitoring the progress of the flight with radar, guiding the pilot through the descent to the airport/heliport or to a specific runway.

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 beam

The focused energy radiated by radar similar to a flashlight or searchlight beam.

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 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 Identified Aircraft

An aircraft, the position of which has been correlated with an observed target or symbol on the radar display.

Radar Monitoring

The radar flight-following of aircraft, whose primary navigation is being performed by the pilot, to observe and note deviations from its authorized flight path, airway, or route. When being applied specifically to radar monitoring of instrument approaches; i.e., with precision approach radar (PAR) or radar monitoring of simultaneous ILS/MLS approaches, it includes advice and instructions whenever an aircraft nears or exceeds the prescribed PAR safety limit or simultaneous ILS/MLS no transgression zone.

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 spacing of aircraft in accordance with established minima.

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 summary chart

A weather product derived from the national radar network that graphically displays a summary of radar weather reports.

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 weather report (SD)

A report issued by radar stations at 35 minutes after the hour, and special reports as needed. Provides information on the type, intensity, and location of the echo tops of the precipitation.

Radarsonde observation

A rawinsonde observation in which winds are determined by radar tracking a balloon-borne target.

Radial

A magnetic bearing extending from a VOR/VORTAC/TACAN navigation facility.

Radials

The courses oriented from a station.

Radiation

The emission of energy by a medium and transferred, either through free space or another medium, in the form of electromagnetic waves.

Radiation fog

Fog characteristically resulting when radiational cooling of the earth’s surface lowers the air temperature near the ground to or below its initial dew point on calm, clear nights.

Radio

A device used for communication.

Radio

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

Nondirectional Beacon.

Radio frequency (RF)

A term that refers to alternating current (AC) having characteristics such that, if the current is input to antenna, an electromagnetic (EM) field is generated suitable for wireless broadcasting and/or communications.

Radio frequency (RF)

Radio magnetic indicator (RMI)

An electronic navigation instrument that combines a magnetic compass with an ADF or VOR. The card of the RMI acts as a gyro-stabilized magnetic compass, and shows the magnetic heading the aircraft is flying.

Radio magnetic indicator (RMI)

Radio or radar altimeter

An electronic altimeter that determines the height of an aircraft above the terrain by measuring the time needed for a pulse of radio-frequency energy to travel from the aircraft to the ground and return.

Radio or radar altimeter

Radio wave

An electromagnetic wave (EM wave) with frequency characteristics useful for radio transmission.

Radio wave

An electromagnetic (EM ) wave with frequency characteristics useful for radio transmission.

Radiosonde

A weather instrument that observes and reports meteorological conditions from the upper atmosphere. This instrument is typically carried into the atmosphere by some form of weather balloon.

Radiosonde observation

A sounding made by the instrument.

RAIL

Runway Alignment Indicator Lights Sequenced Flashing Lights Which Are Installed Only In Combination With Other Light Systems

RAIM

Receiver Autonomous Integrity Monitoring.

RAIM

Receiver Autonomous Integrity Monitoring

Rain

A form of precipitation; drops are larger than drizzle and fall in relatively straight, although not necessarily vertical, paths as compared to drizzle which falls in irregular paths.

Rain shower

Precipitation from a cumuliform cloud; characterized by the suddenness of beginning and ending, by the rapid change of intensity, and usually by rapid change in the appearance of the sky; showery precipitation in the form of rain.

RAIS

Remote Airport Information Service

RAM recovery

The increase in thrust as a result of ram air pressures and density on the front of the engine caused by air velocity.

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.

Ramp Weight

The total weight of the aircraft while on the ramp. It differs from takeoff weight by the weight of the fuel that will be consumed in taxiing to the point of takeoff.

Random RNAV routes

Direct routes, based on area navigation capability, between waypoints defined in terms of latitude/longitude coordinates, degree-distance fixes, or offsets from established routes/airways at a specified distance and direction.

Random RNAV routes

Random Route

Any route not established or charted/published or not otherwise available to all users.

Range attenuation

Reduction of radar power density because of distance from the antenna. It occurs in the outgoing beam at a rate proportional to 1/(range²) The return signal is also attenuated at the same rate.

Range resolution

The ability of radar to distinguish between targets on the same azimuth but at different ranges.

Range-height indicator (RHI) scope

A radar indicator scope displaying a vertical cross section of targets along a selected azimuth.

Ranging signals

Transmitted from the GPS satellite, these allow the aircrafts receiver to determine range (distance) from each satellite.

Ranging signals

Transmitted from the GPS satellite, signals allowing the aircraft’s receiver to determine range (distance) from each satellite.

RAOB

A radiosonde observation.

Rapid decompression

The almost instantaneous loss of cabin pressure in aircraft with a pressurized cockpit or cabin.

Rate Of Turn

The rate in degrees/second of a turn.

Rated 2-minute OEI Power

With respect to rotorcraft turbine engines, the approved brake horsepower developed under static conditions at specified altitudes and temperatures within the operating limitations established for the engine under part 33 of this chapter, for continuation of one flight operation after the failure or shutdown of one engine in multiengine rotorcraft, for up to three periods of use no longer than 2 minutes each in any one flight, and followed by mandatory inspection and prescribed maintenance action.

Rated 21/2-minute OEI power

With respect to rotorcraft turbine engines, the approved brake horsepower developed under static conditions at specified altitudes and temperatures within the operating limitations established for the engine under part 33 of this chapter for periods of use no longer than 21/2minutes each after the failure or shutdown of one engine of a multiengine rotorcraft.

Rated 30-minute OEI power

With respect to rotorcraft turbine engines, the approved brake horsepower developed under static conditions at specified altitudes and temperatures within the operating limitations established for the engine under part 33 of this chapter, and limited in use to one period of use no longer than 30 minutes after the failure or shutdown of one engine of a multiengine rotorcraft.

Rated 30-second OEI Power

With respect to rotorcraft turbine engines, the approved brake horsepower developed under static conditions at specified altitudes and temperatures within the operating limitations established for the engine under part 33 of this chapter, for continuation of one flight operation after the failure or shutdown of one engine in multiengine rotorcraft, for up to three periods of use no longer than 30 seconds each in any one flight, and followed by mandatory inspection and prescribed maintenance action.

Rated continuous OEI power

With respect to rotorcraft turbine engines, the approved brake horsepower developed under static conditions at specified altitudes and temperatures within the operating limitations established for the engine under part 33 of this chapter, and limited in use to the time required to complete the flight after the failure or shutdown of one engine of a multiengine rotorcraft.

Rated maximum continuous augmented thrust

With respect to turbojet engine type certification, the approved jet thrust that is developed statically or in flight, in standard atmosphere at a specified altitude, with fluid injection or with the burning of fuel in a separate combustion chamber, within the engine operating limitations established under Part 33 of this chapter, and approved for unrestricted periods of use.

Rated maximum continuous power

With respect to reciprocating, turbopropeller, and turboshaft engines, the approved brake horsepower that is developed statically or in flight, in standard atmosphere at a specified altitude, within the engine operating limitations established under Part 33, and approved for unrestricted periods of use.

Rated maximum continuous thrust

With respect to turbojet engine type certification, the approved jet thrust that is developed statically or in flight, in standard atmosphere at a specified altitude, without fluid injection and without the burning of fuel in a separate combustion chamber, within the engine operating limitations established under Part 33 of this chapter, and approved for unrestricted periods of use.

Rated takeoff augmented thrust

With respect to turbojet engine type certification, the approved jet thrust that is developed statically under standard sea level conditions, with fluid injection or with the burning of fuel in a separate combustion chamber, within the engine operating limitations established under Part 33 of this chapter, and limited in use to periods of not over 5 minutes for takeoff operation.

Rated takeoff power

With respect to reciprocating, turbopropeller, and turboshaft engine type certification, the approved brake horsepower that is developed statically under standard sea level conditions, within the engine operating limitations established under Part 33, and limited in use to periods of not over 5 minutes for takeoff operation.

Rated takeoff thrust

With respect to turbojet engine type certification, the approved jet thrust that is developed statically under standard sea level conditions, without fluid injection and without the burning of fuel in a separate combustion chamber, within the engine operating limitations established under Part 33 of this chapter, and limited in use to periods of not over 5 minutes for takeoff operation.

Rating

A statement that, as a part of a certificate, sets forth special conditions, privileges, or limitations.

Rawin

A rawinsonde observation.

Rawinsonde observation

A combined winds aloft and radiosonde observation. Winds are determined by tracking the radiosonde by radio direction finder or radar.

RB

Relative Bearing.

RB

Relative Bearing.

RBI

Relative Bearing Indicator.

RBI

Relative Bearing Indicator.

RBN

Radio Beacon.

RCAG

Remote Center Air/Ground

RCC

Rescue Coordination Center

RCLM

Runway Centerline Marking.

RCLS

Runway Centerline Light System.

RCLS

Runway Centerline Lighting System

RCO

Remote Communications Outlet.

RCO

Remote Communications Outlet

RD

Rotor Diameter

RDOF

Radio Failure

Read Back

Repeat my message back to me.

Readiness

A principle of learning where the eagerness and single-mindedness of a person toward learning affect the outcome of the learning experience.

Receiver

In communication, the listener, reader, or student who takes in a message containing information from a source, processes it, reacts with understanding, and changes behavior in accordance with the message.

Receiver autonomous integrity monitoring (RAIM)

A system used to verify the usability of the received GPS signals and warns the pilot of any malfunction in the navigation system. This system is required for IFR-certified GPS units.

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.

Receiver autonomous integrity monitoring (RAIM).

A system used to verify the usability of the received GPS signals and warns the pilot of any malfunction in the navigation system. This system is required for IFR-certified GPS units.

Receiver-transmitter (RT)

A system that receives and transmits a signal and an indicator.

Receiver-transmitter (RT)

A system that receives and transmits a signal and an indicator.

Recency

Principle of learning stating that things learned recently are remembered better than things learned some time ago. As time passes, less is remembered. Instructors use this principle when summarizing the important points at the end of a lecture in order for students to better remember them.

Reciprocating Engine

An engine that converts the heat energy from burning fuel into the reciprocating movement of the pistons. This movement is converted into a rotary motion by the connecting rods and crankshaft.

Recommended altitude

An altitude depicted on an instrument approach chart with the altitude value neither underscored nor overscored. The depicted value is an advisory value.

Reduce Speed To (Speed)

Speed Adjustment.

Reduced vertical separation minimum (RVSM)

Reduces the vertical separation between flight levels (FL) 290 and 410 from 2,000 feet to 1,000 feet, and makes six additional FLs available for operation. Also see DRVSM.

Reduced Vertical Separation Minimums (RVSM)

RVSM airspace is where air traffic control separates aircraft by a minimum of 1,000 feet vertically between flight level (FL) 290 and FL 410 inclusive. RVSM airspace is special qualification airspace; the operator and the aircraft used by the operator must be approved by the Administrator. Air traffic control notifies operators of RVSM by providing route planing information.

Reduction Factor

A number, usually 100 or 1,000 by which a moment is divided to produce a smaller number that is less likely to cause mathematical errors when computing the center of gravity.

Reduction Gear

The gear arrangement in an aircraft engine that allows the engine to turn at a faster speed than the propeller.

Reference circle (also, distance circle)

The circle depicted in the plan view of an IAP chart that typically has a 10 NM radius, within which chart the elements are drawn to scale.

Reference Datum

(GAMA) An imaginary vertical plane from which all horizontal distances are measured for balance purpose.

Reference landing speed

The speed of the airplane, in a specified landing configuration, at the point where it descends through the 50 foot height in the determination of the landing distance.

Reference Landing Speed (Vref)

The speed of the airplane, in a specified landing configuration, at the point where it descends through the 50-foot height in the determination of the landing distance.

Refraction

In radar, bending of the radar beam by variations in atmospheric density, water vapor content, and temperature.

Region Of Reverse Command

Flight regime in which flight at a higher airspeed requires a lower power setting and a lower airspeed requires a higher power setting in order to maintain altitude.

Region of reverse command

Flight regime in which flight at a higher airspeed requires a lower power setting and a lower airspeed requires a higher power setting in order to maintain altitude.

Regions of command

The regions of normal and reversed command refers to the relationship between speed and the power required to maintain or change that speed in flight.

Regions of command

The “regions of normal and reversed command” refers to the relationship between speed and the power required to maintain or change that speed in flight.

Registration Certificate

A State and Federal certificate that documents aircraft ownership.

REIL

Runway End Identifier Lights.

REIL

Runway End Identifier Lights

Relative bearing (RB)

The angular difference between the aircraft heading and the direction to the station, measured clockwise from the nose of the aircraft.

Relative bearing indicator (RBI)

Also known as the fixed- card ADF, zero is always indicated at the top of the instrument and the needle indicates the relative bearing to the station.

Relative humidity

The ratio of the existing amount of water vapor in the air at a given temperature to the maximum amount that could exist at that temperature; usually expressed in percent.

Relative vorticity

Vorticity of the air relative to the Earth, disregarding the component of vorticity resulting from Earth’s rotation.

Relative Wind

The direction of the airflow with respect to the wing. If a wing moves forward horizontally, the relative wind moves backward horizontally. Relative wind is parallel to and opposite the flightpath of the airplane.

Relative wind

Direction of the airflow produced by an object moving through the air. The relative wind for an airplane in flight flows in a direction parallel with and opposite to the direction of flight; therefore, the actual flight path of the airplane determines the direction of the relative wind.

Relay question

Used in response to a student’s question, the student question is redirected to another student.

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.

Reliability

The degree to which test results are consistent with repeated measurements.

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 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 Communications Outlet (RCO)

An unmanned communications facility remotely controlled by air traffic personnel. RCOs serve FSSs and may be UHF or VHF. RCOs extend the communication range of the air traffic facility. RCOs were established to provide 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 IFR cancellations or departure/landing times.

Remote scope

In radar meteorology a “slave” scope remoted from weather radar.

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. (See Compulsory Reporting Points)

Reporting point

A geographical location in relation to which the position of an aircraft is reported.

Repression

Theory of forgetting proposing that a person is more likely to forget information which is unpleasant or produces anxiety.

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 specified level of accuracy defined by a lateral area of confined airspace in which an RNP-certified aircraft operates.

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.

Residual Fuel

Fuel that remains trapped in the system after draining the fuel from the aircraft with the aircraft in level flight attitude. The weight of this residual fuel is counted as part of the empty weight of the aircraft.

Resolution

Pertaining to radar, the ability of radar to show discrete targets separately, i.e., the better the resolution, the closer two targets can be to each other, and still be detected as separate targets.

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

Response

Possible answer to a multiple-choice test item. The correct response is often called the keyed response, and incorrect responses are called distractors.

Restricted area

Airspace designated under 14 CFR part 73 within which the flight of aircraft, while not wholly prohibited, is subject to restriction.

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.

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.

Reverse question

Used in response to a student’s question. Rather than give a direct answer to the student’s query, the instructor returns the question to the same student to provide the answer.

Reverse sensing

The VOR needle appearing to indicate the reverse of normal operation.

Reverse sensing

The VOR needle appearing to indicate the reverse of normal operation.

Reverse Thrust

A condition where jet thrust is directed forward during landing to increase the rate of deceleration.

Reversing Propeller

A propeller system with a pitch change mechanism that includes full reversing capability. When the pilot moves the throttle controls to reverse, the blade angle changes to a pitch angle and produces a reverse thrust, which slows the airplane down during a landing.

Review and evaluation

The fourth and last step in the teaching process, which consists of a review of all material and an evaluation of the students. In the telling and doing technique of flight instruction, this step consists of the instructor evaluating the student’s performance while the student performs the required procedure.

RF

Radio Frequency.

RF

Radio Frequency.

RFFS

Rescue and Firefighting Services.

RFM

Rotorcraft Flight Manual

Rhetorical question

Generally, a question asked for a purpose other than to obtain the information the question asks. For this handbook’s purpose, a question asked to stimulate group thought. Normally answered by the instructor, it is more commonly used in lecturing rather than in guided discussions.

Rhodopsin

The photosensitive pigments that initiate the visual response in the rods of the eye.

Ridge (also called ridge line)

In meteorology, an elongated area of relatively high atmospheric pressure; usually associated with and most clearly identified as an area of maximum anticyclonic curvature of the wind flow (isobars, contours, or streamlines).

Rigging

The final adjustment and alignment of an aircraft and its flight control system that provides the proper aerodynamic characteristics.

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.

Rigidity

The characteristic of a gyroscope that prevents its axis of rotation tilting as the Earth rotates.

Rigidity

The characteristic of a gyroscope that prevents its axis of rotation tilting as the Earth rotates.

Rigidity in space

The principle that a wheel with a heavily weighted rim spinning rapidly will remain in a fixed position in the plane in which it is spinning.

RIL

Runway Intersection Lights

Rime ice

Rough, milky, opaque ice formed by the instantaneous freezing of small supercooled water droplets.

Rime ice

Rough, milky, opaque ice formed by the instantaneous freezing of small supercooled water droplets.

Rime Ice

A rough, milky, opaque ice formed by the instantaneous freezing of small, supercooled water drops. It is generally rougher in appearance than clear ice.

Risk

The future impact of a hazard that is not eliminated or controlled.

Risk

The future impact of a hazard that is not eliminated or controlled.

Risk elements

There are four fundamental risk elements in aviation: the pilot, the aircraft, the environment, and the type of operation that comprise any given aviation situation.

Risk management

The part of the decision-making process which relies on situational awareness, problem recognition, and good judgment to reduce risks associated with each flight.

Risk management

The part of the decision-making process which relies on situational awareness, problem recognition, and good judgment to reduce risks associated with each flight.

RJ

Regional Jet

RLIM

Runway Light Intensity Monitor

RLSD

Released

RMI

Radio Magnetic Indicator.

RMI

Radio Magnetic Indicator

RNAV

Area Navigation.

RNAV

Area Navigation

RNAV Approach

An instrument approach procedure which relies on aircraft area navigation equipment for navigational guidance.

RNAV DP

A DP developed for RNAV-equipped aircraft whose ground track is based on satellite or DME/DME navigation systems.

RNP

Required Navigation Performance.

RNP

Required Navigation Performance

ROC

Required Obstacle Clearance

Rocket

An aircraft propelled by ejected expanding gases generated in the engine from self-contained propellants and not dependent on the intake of outside substances. It includes any part which becomes separated during the operation.

Rocketsonde

A type of radiosonde launched by a rocket and making its measurements during a parachute descent; capable of obtaining soundings to a much greater height than possible by balloon or aircraft.

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.

Roll

The motion of the aircraft about the longitudinal axis. It is controlled by the ailerons.

Roll cloud

A dense and horizontal roll-shaped accessory cloud located on the lower leading edge of a cumulonimbus or less often, a rapidly developing cumulus; indicative of turbulence. Sometimes improperly called rotor cloud.

Roll-out RVR

The RVR readout values obtained from sensors located nearest the rollout end of the runway.

Rote learning

A basic level of learning in which the student has the ability to repeat back something learned, with no understanding or ability to apply what was learned.

Rotor cloud

A turbulent cloud formation found in the lee of some large mountain barriers, the air in the cloud rotates around an axis parallel to the range; indicative of possible violent turbulence. Sometimes improperly called roll cloud.

Rotorcraft

A heavier-than-air aircraft that depends principally for its support in flight on the lift generated by one or more rotors.

Rotorcraft-load combination

The combination of a rotorcraft and an external-load, including the external-load attaching means. Rotorcraft-load combinations are designated as Class A, Class B, Class C, and Class D, as follows:
(1) Class A rotorcraft-load combination means one in which the external load cannot move freely, cannot be jettisoned, and does not extend below the landing gear.
(2) Class B rotorcraft-load combination means one in which the external load is jettisonable and is lifted free of land or water during the rotorcraft operation.
(3) Class C rotorcraft-load combination means one in which the external load is jettisonable and remains in contact with land or water during the rotorcraft operation.
(4) Class D rotorcraft-load combination means one in which the external-load is other than a Class A, B, or C and has been specifically approved by the Administrator for that operation.

Roundout (Flare)

A pitch-up during landing approach to reduce rate of descent and forward speed prior to touchdown.

Route

A defined path, consisting of one or more courses in a horizontal plane, which aircraft traverse over the surface of the earth.

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.

RPAT

RNP Parallel Approach Runway Transitions

RR

Low or Medium Frequency Radio Range Station.

RRTES

Reroutes

RSA

Runway Safety Area

RSP

Runway Safety Program

RT

Receiver-Transmitter.

Rudder

The movable primary control surface mounted on the trailing edge of the vertical fin of an airplane. Movement of the rudder rotates the airplane about its vertical axis.

Rudder

The movable primary control surface mounted on the trailing edge of the vertical fin of an airplane. Movement of the rudder rotates the airplane about its vertical axis.

Ruddervator

A pair of control surfaces on the tail of an aircraft arranged in the form of a V. These surfaces, when moved together by the control wheel, serve as elevators, and when moved differentially by the rudder pedals, serve as a rudder.

Ruddervator

Runback Ice

Ice that forms from the freezing or refreezing of water leaving protected surfaces and running back to unprotected surfaces.

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 Centerline Lights

Runway centerline lights are installed on some precision approach runways to facilitate landing under adverse visibility conditions. They are located along the runway centerline and are spaced at 50-foot intervals. When viewed from the landing threshold, the runway centerline lights are white until the last 3,000 feet of the runway. The white lights begin to alternate with red for the next 2,000 feet, and for the last 1,000 feet of the runway, all centerline lights are red.

Runway Centerline Markings

The runway centerline identifies the center of the runway and provides alignment guidance during takeoff and landings. The centerline consists of a line of uniformly spaced stripes and gaps.

Runway Edge Lights

Runway edge lights are used to outline the edges of runways during periods of darkness or restricted visibility conditions. These light systems are classified according to the intensity or brightness they are capable of producing: they are the High Intensity Runway Lights (HIRL), Medium Intensity Runway Lights (MIRL), and the Low Intensity Runway Lights (LIRL). The HIRL and MIRL systems have variable intensity controls, whereas the LIRLs normally have one intensity setting.

Runway end identifier lights (REIL)

A pair of synchronized flashing lights, located laterally on each side of the runway threshold, providing rapid and positive identification of the approach end of a runway.

Runway end identifier lights (REIL)

A pair of synchronized flashing lights, located laterally on each side of the runway threshold, providing rapid and positive identification of the approach end of a 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 numbers on the runway. Pilots cleared to “fly or maintain runway heading” are expected to fly or maintain the published heading that corresponds with the extended centerline of the departure runway (until otherwise instructed by ATC), and are not to apply drift correction; e.g., RWY 4, actual magnetic heading of the runway centerline 044.22°, fly 044°.

Runway Hotspots

Locations on a particular airport that historically have hazardous intersections. Hot spots alert pilots to the fact that there may be a lack of visibility at certain points or the tower may be unable to see that particular intersection. Whatever the reason, pilots need to be aware that these hazardous intersections exist and they should be increasingly vigilant when approaching and taxiing through these intersections. Pilots are typically notified of these areas by a Letter to Airmen or by accessing the FAA Office of Runway Safety.

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 Incursion

An occurrence at an airport involving an aircraft, vehicle, person, or object on the ground that creates a collision hazard or results in a loss of separation with an aircraft that is taking off, intending to take off, landing, or intending to land.

Runway Incursion

Any occurrence at an airport involving an aircraft, vehicle, person, or object on the ground that creates a collision hazard or results in loss of separation with an aircraft taking off, intending to takeoff, landing, or intending to land.

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 Safety Program (RSP)

Designed to create and execute a plan of action that reduces the number of runway incursions at the nations airports.

Runway temperature

The temperature of the air just above a runway, ideally at engine and/or wing height, used in the determination of density altitude; useful at airports when critical values of density altitude prevail.

Runway Threshold Markings

Runway threshold markings come in two configurations. They either consist of eight longitudinal stripes of uniform dimensions disposed symmetrically about the runway centerline, or the number of stripes is related to the runway width. A threshold marking helps identify the beginning of the runway that is available for landing. In some instances, the landing threshold may be displaced.

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

The meteorological visibility along an identified runway determined from a specified point on the runway; may be determined by a transmissometer or by an observer.

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 visibility value (RVV)

The visibility determined for a particular runway by a transmissometer.

Runway visual range

An instrumentally derived horizontal distance a pilot should see down the runway from the approach end; based on either the sighting of high intensity runway lights or on the visual contrast of other objects, whichever yields the greatest visual range.

Runway Visual Range (RVR)

An estimate of the maximum distance at which the runway, or the specified lights or markers delineating it, can be seen from a position above a specific point on the runway centerline. RVR is normally determined by visibility sensors or transmissometers located alongside and higher than the centerline of the runway. RVR is reported in hundreds of feet.

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 [ICAO]

A defined rectangular area on a land aerodrome prepared for the landing and take-off of aircraft.

RVR

Runway Visual Range.

RVR

Runway Visual Range as measured in the Touchdown Zone Area.

RVSM

Reduced Vertical Separation Minimums

RVSM

Reduced Vertical Separation Minimum

RVV

Runway Visibility Value.

RVV

Runway Visibility Value.

RWSL

Runway Status Light

RWY

Runway

RWY

Runway

RWY CONFIG

Runway Configuration

RY

Runway

Restrict the list to specific categories by clicking on the menubar at the top of the screen.