RESULTS FROM THE NASA AUTOMATED NAP-OF-THE-EARTH PROGRAM

Military helicopter Nap-of-the-Earth (NOE) flight is one of the most d emanding low-altitude, near terrain night operations, In NOE, the pilo t is operating at or below tree-top levels, taking maximum advantage o f the terrain and ground features for concealment. Such increased prox imity to obstructions places heightened maneuverability requirements o n the aircraft and extreme levels of workload on the pilot. The basic issue being addressed in the NASA Automated Nap-of-the-Earth (ANOE) pr ogram is the intelligent use of environmental information such as know ledge of terrain, obstacles, and other external factors to enhance the flight path guidance of the vehicle, This is a major departure over c ontemporary guidance and control based on feedback of state variables such as vehicle attitudes, velocities, and accelerations, Although the immediate program has a military focus, the technological advances in herent for automating NOE flight have great benefit to the operation o f a wide class of vehicles such as emergency medical helicopters, conv entional and high-speed transports, unmanned aerial vehicles, and plan etary vehicles, This paper summarizes results to date of the NASA ANOE program in the areas of passive and active sensors, pilot displays, l ow-altitude manual trajectory guidance, and NOE automatic guidance, Ea ch of these areas has been developed and evaluated in piloted, motion- based simulation or through flight test, These evaluations have demons trated the feasibility of automating the NOE flight mission, and have generated additional spin-off applications of the technologies.