Definitions for "VASI"
Keywords:  runway, glide, pilot, guidance, slope
Visual Approach Slope Indicator - An airport lighting facility in the terminal area navigation system used primarily under Visual Flight Rules conditions. It provides vertical visual guidance to aircraft during approach and landing, by radiating a pattern of high intensity red and white focused light beams, which indicate to the pilot that he/she is above, on, or below the glide path.
Visual Approach Slope Indicator. A pair of lights to the side of the runway that tells the pilot that the plane is on a safe and reasonable descent to the runway. Red lights over white is the right thing to see. It's only vertical (up/down) guidance. Everyone pronounces the acronym rather than expanding it.
Visual Approach Slope Indicator. A series of lights using Fresnel lenses that cause them to change colors at different viewing angles, providing visual cues to pilots as to whether their aircraft is on the correct (or incorrect) vertical path for an approach to a runway.
Keywords:  weapon