机务英语口语

RCL - runway centre-line.

RBI - relative bearing indicator, displaying inＦＯＲＭation from the ADF.

RDO - radio.

RIS - Radar InＦＯＲＭation Service. Provided to notify pilots of conflicting traffic outside regulated airspace, but offering no avoiding action.

RMI - radio magnetic indicator. A navigation aid which combines DI, VOR and/or ADF display and will indicate bearings to stations, together with aircraft heading.

RMK - remark(s).

RMU - radio management unit.

Rnav - area navigation. A system of radio navigation which permits direct point-to-point off-airways navigation by means of an on-board computer creating phantom VOR/DME transmitters termed waypoints.

RON - remain over night (night-stop).

root - inner end of wing where it meets fuselage.

rpm - revolutions per minute.

r/t or RT - radio telephony. Voice communications, as opposed to WT, wireless telegraphy

RTF - radio telephony.

RVR - runway visual range, a horizontal measurement of visibility along a runway.

rwy - runway.

Rx - receiver. S

SACP - (CAA) Standing Advisory Committee on Pilot Licensing.

SAR - search-and-rescue. Also Sarsat, SAR satellite.

SAS - stability augmentation system. An automatic flight control system employed in many helicopters and some fixed-wing aircraft to enhance their stability and handling qualities.

SATCO - senior air traffic control officer

satcoms - satellite communications, now being introduced on intercontinental airliners and business jets for (non- operational) air-to-ground voice communications via ground relay stations.

SB - Service Bulletin. Advisory notices issued by aircraft, engine and

equipment manufacturers alerting owners and engineers to faults or problems requiring preventitive or remedial maintenance or modification. Often termed \ (which see).

SBAC - Society of British Aerospace Companies. The UK aerospace manufacturers\ trade association.

SDAU - Safety Data Analysis Unit of the CAA.

\ flying courses designed to enable non-pilot light aircraft passengers to take control and land in an emergency such as pilot incapacitation. Also standby or safety pilot and pinch-hitter (U.S.)

Sectional - (U.S.) VFR navigation chart, equivalent to our 1:500,000 or \

Semi-circular - system of cruising altitudes.

SELCAL - selective calling. A high-frequency system enabling air traffic control to alert a particular aircraft, by means of flashing light or aural signal in the cockpit, for receipt of a message without the crew having to

maintain a listening watch. Used on long-haul over-ocean airline routes and by intercontinental bizjets.

sfc - specific fuel consumption of an engine, expressed in pounds of fuel consumed for each unit of power (hp, shp, lb/st) produced. Also surface.

short final - radio call made from aircraft calling later than final position, or on final approach from a shortened circuit, or at 2nm from threshold on a straight-in approach.

shp - shaft horsepower.

SID - standard instrument departure. A standard IFR departure route enabling air traffic controllers to issue abbreviated clearances and thus speed the flow of traffic.

SIGMET - warning of severe weather conditions (active thunderstorms, hail, severe turbulence, icing etc.) issued my Met offices.

sl - sea level.

SLA - small light aircraft

SLMG - self-launching motor glider

SMOH - since major overhaul. Term used in aircraft for sale advertisements where engine hours are quoted (see TBO). Also STOH, TTSN, TTAF/E

SMR - surface movement radar.

SNOWTAM - a NOTAM concerning runway conditions in snow.

SOB - souls on board, the number of persons on board an aircraft. Also POB.

socked-in - A colloquialism referring to an airport closed to air traffic by bad weather, similarly clamped.

SOP - standard operating procedure.

specific range - measure of an aircraft\ nautical miles flown per pound of fuel burned (nm/lb)

SPL - Student Pilot\ certificate serves as an SPL.

squawk - to transmit an assigned code via a transponder (see SSR below).

SR - sunrise.

SRG - Safety Regulation Group of the CAA

SRZ - Special Rules Zone. An area of protected airspace surrounding an airfield and extending from the surface upwards to a specific level which affords safety to air traffic movements in the vicinity of airfields whose

traffic level does not warrant the establishment of a Control Zone. Also SRA, Special Rules Area. extending vertically and horizontally from a level above the surface, but not necessarily terminating at the same upper level as the SRZ.

SRA - Surveillance Radar Approach. Also Special Rules Area.

SRE - Surveillance Radar Element of a GCA.

SS - sunset.

SSB - single sideband. Reduction of bandwith by transmitting only one sideband and suppressing the other, and usually also the carrier wave.

SSR - secondary surveillance radar. A radar system comprising a ground-based transmitter/receiver which interrogates a compatible unit in the aircraft (see transponder), providing instant radar identification without having to

manoeuvre. Assigned four-digit transponder codes are referred to as squawk codes.

STAR - Standard Terminal Arrival Route, for inbound IFR traffic.

STC - Supplemental Type Certificate. U.S. system for post-type certification approval of aircraft modifications such as re- engining, STOL kits, etc, where the full certification process is not deemed necessary. Also used by

manufacturers to certify (often greatly changed) new models of old types under so-called \

STOH - since top overhaul

STOL - short take-off and landing. Also VTOL, V/STOL,

STOVL - short take-off, vertical landing. T

T - true. Also TH, true heading, and TT, true track.

TACAN - tactical air navigation system. An ultra-high frequency electronic navigation aid which provides suitably-equipped aircraft with a continuous indication of bearing and distance to the selected Tacan station. The distance element can be received by civilian DMF equipment, but otherwise Tacan is principally a military navaid.

TAF - Terminal Area Forecast.

TAS - true airspeed. Rectified airspeed corrected for altitude and outside air temperature.

TBO - time between overhauls, an engine manufacturer\ interval in hours, a rough and not guaranteed guide to life expectancy of an aero-engine before it will need overhaul.

TCA - Terminal Control Area (USA).

TCAS - traffic alert and collision avoidance system. U.S. developed

radar-based airborne collision avoidance system operating independently of ground-based equipment. TCAS-I generates traffic advisories only, TCAS-II provides advisories and collision avoidance instructions in the vertical plane.

TEMPO - temporarily, term used in Met reports.

TET - turbine entry temperature.

TGT - turbine gas temperarture.

THR or thld - threshold.