时间:2011-03-11 23:18来源:蓝天飞行翻译 作者:航空 点击:次
transonic flight. Flight in which an airplane transitions from subsonic speed to a speed at or beyond the speed of sound. Transonic flight is considered to be between about 600 and 900 miles per hour, a speed of between Mach 0.8 and Mach 1.2. At this speed, some air passing over the aircraft is subsonic and other air is supersonic. Abrupt changes in the flight characteristics of an airplane take place in transonic flight. transparent. The condition of a material that allows rays of light to pass through it without being diffused, or scattered. Clear glass is transparent, allowing objects seen through it to be recognized. transponder (radar beacon transponder). The airborne radar beacon receiver/transmitter portion of the air traffic control radar beacon system (ATCRBS). The transponder automatically receives radio signals from interrogators on the ground, and it selectively replies from a specific reply pulse or pulse group only to those interrogations being received on the mode to which it is set to respond. See radar beacon transponder. transverse pitch (rivet spacing). The distance between the center of rivets in two adjacent rows. Transverse pitch is also called rivet gage. See illustration for gage (rivet). transverse wave. A type of mechanical wave in which the material being vibrated moves in a direction perpendicular to the direction the wave is moving. Transverse waves are formed when a rock is thrown into a pond of water. The surface of the water moves up and down as the wave moves across the pond. trend monitoring (turbine engine maintenance). A system for monitoring the performance of a turbine engine by routine comparison of performance parameters with a base line of the same parameters established when the engine was new or newly overhauled. EGT, RPM, fuel flow, and oil consumption are monitored on every flight, and the difference between the current indication and the base line is plotted. Any deviation from a normal increase or decrease warns the technician of an impending problem. triangle. A closed, plane, three-sided figure. The sum of the three angles in a triangle is always 180°. triangulation (navigation). A method of determining the location of an aircraft by radio bearings. Lines |