時間：2011-09-15 17:20來源：藍(lán)天飛行翻譯 作者：航空 點擊：次
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vdu visual display unit VFR Visual Flight Rules. Prescribed for the operation of aircraft in visual meteorological conditions (VMC).VMC is generally defined as five miles visibility or more and 1,000 feet vertical and one nautical mile horizontal clearance from cloud, but variations apply to aircraft operating below 3,000 feet amsl. Special VFR (SVFR) clearances are granted at the discretion of ATC for VFR flight through some controlled airspace where IFR usually apply. Also CVFR, Controlled VFR Flight. VGS Volunteer Gliding School (RAF Air Cadets) VHF very high frequency. Radio frequencies in the 30-300 MHz band, used for most civil air-to-ground communication. vis visibility VLA very light aircraft VLF very low frequency. Radio frequencies in the 3-30 kHz band. VLF/Omega worldwide system of long-range navigation using VLF radio transmission. VMC Visual Meterorological Conditions. See VFR, above. Vnav vertical navigation Vne never exceed airspeed Volmet continuous recorded broadcasts of weather conditions at selected airfields. VOR very high frequency omnidirectional range. A radio navigation aid operating in the 108-118 MHz band. A VOR ground station transmits a two-phase directional signal through 360ø. the aircraft's VOR receiver enables a pilot to identify his radial or bearing from/to the ground station. VOR is the most commonly used radio navigation aid in private flying. Increased accuracy is available in Doppler VORs (DVOR) which have replaced some VOR is the UK system. Also VORTAC, combined VOR and TACAN, and VOT, VOR test facility. VP variable-pitch (propeller), whose blade angle can be altered in flight either automatically or manually. Vr Rotation speed VRP visual reference point. (In the UK) Landmarks used for position reporting by aircraft operating VFR. VSI vertical speed indicator. One of the primary flight instruments showing rate of climb or descent. Also IVSI, instantaneous VSI. |
