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APPENDIX—GLOSSARY OF TECHNICAL TERMS - In view of the appearance in the report of a number of unfamiliar words peculiar to aeronautics, it has been considered desirable to include a brief explanation of their meanings. Aeradio station is an aeronautical communications station operated to provide communication for aeronautical purposes. Apron is a paved or surfaced area where aircraft stand for purposes of loading or unloading passengers, cargo, refuelling, parking, or maintenance. Dimensional practices comprise the adoption and use of standard units of measurement in communications between ground and aircraft stations. Direction-finding station is a radio-station equipped with special apparatus for obtaining radio bearings. D.M.E. is a radar navigational system used by aircraft to determine their position,. and/or distance in respect to the airfield. Instrument rating is a rating in a Pilot's Licence authorizing him to fly under instrument flight rules. " Q " Code is a code consisting of three-letter abbreviations designed to expedite radio communications procedures between aircraft and ground stations. Radio Beacon is a special radio navigational aid, the emissions of which are intended to enable a mobile station to determine its radio bearing or direction with reference to the radio beacon station. Radio calibration is the checking of the operational accuracy of any radio aid to navigation or landing. Radio channel is any link of radio communication between two stations. Radio fan-marker is a low-powered radio beacon emitting a vertical fan-shaped pattern. Radio frequency indicates the number of oscillations per second of a particular radio signal. Radio range : A form of radio beacon the emissions of which provide definite track guidance along four paths, one in each quadrant, emanating from the range station. Splits and legs are terms used in reference to radio ranges. Legs are the track delineated by a radio range. Splits are multiple patterns occurring on one or more legs resulting in false tracks.

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