Glossary     Term Definition AGL Above Ground Level AIM Aeronautical Information Manual Air Care Alliance A national league of organizations whose pilots and other volunteers fly patients and perform other public benefit missions. Members include most such groups. See http://www.aircareall.org for details and contact information. Air Carrier Person who undertakes directly by lease, or other arrangement, to engage in air transportation. air miss breach of the specified minima of proximity between two aircraft. Air Traffic aircraft operating in the air or on airport surface, exclusive of loading ramps and parking areas Air traffic clearance An authorization by air traffic control, for the purpose of preventing collision between known aircraft, for an aircraft to proceed under specified traffic conditions iwthin controlled airspace. Airfoil Any surface designed to obtain a useful reaction, or lift, from air passing over it. Airplane wings, propeller blades, and helicopter rotors are examples of airfoils. Airframe The fuselage, booms, nacelles, cowlings, fairing, airfoil surfaces (indluding rotors but excluding propellers and rotating airfoils of engines), and landing gear of an aircraft and their accessories and controls. Airship Engine-driven lighter-than-air aircraft that can be steered. Alert Area Established to inform pilots of a specific area wherein a high volume of pilot training or an unusual type of aeronautical activity is conducted. ALS Approach Light System AOG Aicraft on Ground Area navigation low route An area navigation route within the airspace extending upward from 1.200 feet above the surface of the earth to, but not including, 18,000 feet MSL. ASR Airport Surveillance Radar ATC Air Traffic Control - service operated by appropriate authority to promote the safe, orderly, and expeditious flow of air traffic. Autorotation Rotorcraft flight condition in which the lifting rotor is driven entirely by action of the air when the rotorcraft is in motion. This is usually an engine-out situation in a helicopter. Balloon Lighter-than-air aircraft that is not engine driven, and that sustains flight through the use of either gas buoyancy or an airborne heater. Bush Pilot One who operates an STOL type aircraft successfully on a daily basis in off airport operations. Canard An aircraft configuration in which the span of the forward wing is substantially less than that of the main wing. Examples are the Long-EZ kit plane and the Wright Flyer. CAS Calibrated Airspeed - the indicated airspeed of an aircraft, corrected for position and instrument error. CAS is equal to true airspeed in standard atmosphere at sea level. CAT II Category II CAVU Ceiling and visibility unlimitedJeff Ott Ceiling Height above the earth's surface of the lowest layer of clouds or obscuring phenomena that is reported as "broken", "overcast", or "obscuration", and not classified as "thin" or "partial". Commercial Operator Person who, for compensation or hire, engages in the carriage by aircraft in air commerce of persons or property. CONSOL kind of low or medium frequency long range navigational aid Critical Altitude The maximum altitude at which, in standard atmosphere, it is possible to maintain, at a specified rotational speed, a specified power or a specified manifold pressure. Critical Altitude is the maximum altitude at which it is possible to maintain the maximum continuous horsepower, or the maximum continuous rated manifold pressure. Critical Engine The engine whose failure would most adversely affect the performance or handling qualities of an aircraft. Decision Height The height at which a decision must be made, during an ILS or PAR instrument approach, to either continue the approach or to execute a missed approach. DH Decision Height DME Distance Measuring Equipment compatible with TACAN EAS equivalent airspeed Equivalent airspeed The calibrated airspeed of an aircraft corrected for adiabatic compressible flow for the particular altitude. Equivalent airspeed is equal to calibrated airspeed in standard atmosphere at sea level. Extended over-water operation Operation of an aircraft over water at a horizontal distance of more than 50 nautical miles from the nearest shoreline. FAA Federal Aviation Administration FAR Federal Aviation Regulations Flight Level A level of constant atmospheric pressure related to a reference datum of 29.92 inches of mercury. i.e. Flight Level 250 represents a barometric altimeter indication of 25,000 feet. FM Fan Marker Glider A heavier-than-air aircraft that is supported in flight by the dynamic reaction of the air against its lifting surfaces and whose free flight does not depend principally on an engine. An example is the Nimbus III GS Glide Slope Gyrodyne A rotorcraft whose rotors are normally engine-driven for takeoff, hovering, and landing, and for forward flight through part of its speed range, and whose means of propulsion, consisting usually of conventional propellers, is independent of the rotor system. Gyroplane Rotorcraft whose rotors are not engine-driven, except for initial starting, but are made to rotate by action of the air when the rotorcraft is moving; and whose means of propulsion, consisting usually of conventional propellers, is independent of the rotor system. HIRL High-Intensity Runway Light system IAS Indicated Airspeed ICACO International Civil Aviation Organization IFR Instrument Flight Rules IFR conditions Weather conditions below the miminum for visual flight rules. IFR over-the-top On an IFR flight plan, air traffic control may clear pilot to maintain VFR conditions. ILS Instrument Landing System IM ILS Inner Marker Indicated airspeed The speed of an aircraft as shown on its pitot static airspeed indicator calibrated to reflect standard atmosphere adiabatic compressible flow at sea level uncorrected for airspeed system errors. INT Intersection Large aircraft Aircraft with maximum certificated takeoff weight greater than 12,500 pounds. LASO Land and hold short LDA Localizer-Type Directional Aid LFR Low-Frequency Radio range LMM compass Locator at middle marker LOC ILS localizer LOM compass Locator at Outer Marker M Mach number. Ratio of true airspeed to the speed of sound. MAA Maximum Authorized IFR Altitude MALS Medium intensity Approach Light System MALSR Medium intensity Approach Light System with Runway alignment indicator lights MCA Minimum Crossing Altitude MDA Minimum Descent Altitude MEA Minimum En route IFR Altitude MM ILS middle marker MOA Military Operations Area. Airspace established outside Class A airspace to separate or segregate certain non-hazerdous military activities from IFR Traffic and to identify for VFR traffic where these activities are conducted. i.e. It looks like this on a sectional. MOCA Minimum Obstruction Clearance Altitude MRA Minimum Reception Altitude MSL Mean Sea Level NDB (ADF) Non-Directional Beacon (Automatic Direction Finder) NMAC Near Mid-Air Collision NOPT No Procedure Turn required NOTAM Notice To AirMenGabriele OEI one engine inoperative OM ILS Outer Marker PAR Precision Approach Radar PPH Pounds per hour QNH Altimeter setting (outside USA), relative to Man Sea level RAIL Runway Alignment Indicator Light system RBN Radio Beacon RCLM Runway Centerline Marking RCLS Runway Centerline Light System REIL Runway End Identification Lights RNAV Area Navigation - A method of navigation that permits aircraft operations on any desired course within the coverage of station-referenced navigation signals or within the limits of self-contained system capability. RR low or medium frequency Radio Range station RVR Runway Visual Range as measured in the touchdown zone area SALS Short Approach Light System Scud-Running flying low along the ground to avoid low clouds while still maintaining visibility SMOH Since Major OverHaul - often seen in classified ads - the flight time in hours since the engine was overhauled. Related terms, see TBOH SSALS Simplified Short Approach Light System SSALSR Simplified Short Approach Light System with Runway alignment indicator lights STOL Short Take Off and Landing.Jag Dawadi TACAN ultra-high frequency Tactical Air Navigational Aid TAS True Airspeed TBOH Time Before OverHaul - often seen in classified ads - the flight time in hours until the engine is scheduled to be overhauled in accordance with manufacturer specs. Related terms, see SMOH TCAS Traffic Alert and Collision Avoidance system TDZL Touchdown Zone Lights Tilt Rotor An aircraft whose rotors can be directed to provide vertical take-off and landing, and also tilted forward to provide forward thrust for cruise flight. An example of a Tilt Rotor is the Bell/Boeing V-22 Osprey. TVOR Very high frequency Terminal Omnirange station V1 the maximum speed in the takeoff at which the pilot must take the first action (e.g. apply brakes, reduce thrust, deploy speed brakes) to stop the aircraft within the accelerate-stop distance. V1 also means the minimum speed in the takeoff, following a failure of the critical engine at VEF, at which the pilot can continue the takeoff and achieve the required height above the takeoff surface within the takeoff distance. V2 takeoff safety speed V2min minimum takeoff safety speed VA design maneuvering speed VB design speed for maximum gust intensity VC design crusing speed VD design diving speed VDF/MDF demonstrated flight diving speed VEF speed at which the critical engine is assumed to fail during takeoff VF design flap speed VFCMFC Maximum speed for stability characteristics. A speed that may not be less than a speed midway between maximum operating limit speed (VMO/MMO) and demonstrated flight diving speed. VFE maximum flap extended speed VH maximum speed in level flight with maximum continuous power VLE maximum landing gear extended speed VLO maximum landing gear operating speed VLOF lift-off speed VMC minimum control speed with the critical engine inoperative VMOMMO maximum operating limit speed VMU minimum unstick speed VNE never-exceed speed VNO maximum structural crusing speed VR rotation speed VS stalling speed or the minimum steady flight speed at which the airplane is controllable VS1 stalling speed or the minimum steady flight speed obtained in a specific configuration VSO stalling speed or the minimum steady flight speed in the landing configuration VTOSS takeoff safety speed for Category A rotorcraft VX speed for best angle of climb - the speed at which an aircraft will gain the most altitude in the shortest distance VY speed for the best rate of climb - the speed at which an aircraft will gain the most altitude in the least amount of time VAR Visual Aural RangeJim Rutherford VFR visual flight rules VHF very high frequency VOR very high frequency omnirange station VORTAC collocated VOR and TACAN
Copyright © 1995-2005 James E. McHenry. All rights reserved.
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