Abstract: A system for providing a Head-Up Display (HUD) on board an aircraft to assist a pilot in guiding the aircraft. The display is positioned in the pilot's normal line of sight. In one mode it utilizes a radio beam landing system such as an ILS (Instrument Landing System) to generate symbols that correspond to visual ground cues which, together with an aircraft symbol display, provide the pilot with cues for aligning the aircraft on the appropriate path for approach and landing. The system moves the aircraft symbol in accordance with motion changes of the aircraft. During a landing approach the pilot "flies" the aircraft symbol relative to the simulated and/or real ground cues. By making the HUD correspond with ground cues, the abrupt transition from instrumented to visual flight is eliminated. At altitudes below which available ILS is not acceptable, the system provides a smooth transition to a mode independent of ILS and then to a flare mode.

Abstract: Four generally radially arranged base paths extending outwardly from the center of an airport are provided and each base path is defined by a pair of side-by-side rows of lights with a first row of lights comprising white lights and the second row of lights comprising predetermined color lights different from the color of each other second row of lights. In addition, intermediate radial paths extend outwardly from the airport between adjacent base paths and each intermediate path includes a single row of lights of a color corresponding to the color of lights in the second row of lights of one of the adjacent base paths. Also, a plurality of concentric circular paths extend about the airport at predetermined radial distances therefrom and intersect with the aforementioned base and intermediate paths.