Abbreviation/ Acronym Meaning Abbreviation/ Acronym Meaning VASI . VCOA . VDA . VDP . VFR . VGSI VHF . VIP VLOS VMC VMINI Visual Approach Slope Indicator Visual Climb Over the Airport Vertical Descent Angle Visual Descent Point Visual Flight Rules Visual Glide Slope Indicator Very High Frequency Video Integrator Processor Visual Line of Sight Visual Meteorological Conditions Instrument flight minimum speed, utilized in complying with minimum limit speed requirements for instrument flight Vertical Navigation Never exceed speed Instrument flight never exceed speed, utilized instead of VNE for compliance with maximum limit speed requirements for instrument flight VSO The stalling speed or the minimum steady flight speed in the landing configuration at maximum weight. Vector to Final Vertical Visibility Vertical Velocity Indicator Speed for best rate of climb Instrument climb speed, utilized instead of VY for compliance with the climb requirements for instrument flight WA WAAS . WFO . WGS-84 WMO WMS WMSC . WMSCR AIRMET Wide Area Augmentation System Weather Forecast Office World Geodetic System of 1984 World Meteorological Organization Wide-Area Master Station Weather Message Switching Center Weather Message Switching Center Replacement VO VOR . Visual Observer Very High Frequency Omni-directional Range VORTAC . VHF Omni-directional Range/Tactical Air Navigation VOT . VR VREF . VOR Test Facility VFR Military Training Route The reference landing approach speed, usually about 1.3 times Vso plus 50 percent of the wind gust speed in excess of the mean wind speed. WP WRA WRS . WS WSO WSP . WST . Waypoint Weather Reconnaissance Area Wide-Area Ground Reference Station SIGMET Weather Service Office Weather Systems Processor Convective Significant Meteorological Information WW . Severe Weather Watch Bulletin VNAV VNE . VNEI . Abbreviations/Acronyms VTF . VV VVI . VY VYI Appendix 3-5