Passive Terrain Following

"Special Operations Forces (SOF) MH-47E and MH-60K rotorcraft must use the terrain following tactic to minimize their detectability and maximize their survivability when ingressing or egressing on an operational mission. The current terrain following radarfor these rotorcraft can be detected by passive detection systems, does not always display obstacles accurately, and adds 300 hundred pounds to rotorcraft weight. The juxtaposition of recent advances in GPS navigation and the accuracy and coverage ofDigital Terrain Elevation Data (DTED) offers the possibility of a passive terrain following system for SOF rotorcraft. FTI will conduct a study of the feasibility of a GPS/DTED-based terrain following system and also produce a conceptual design documentand preliminary functional architecture for an operational passive terrain following system. The feasibility study will involve both an anlytic portion and a computer simulation and visualization. Phase II will implement the concepts and designs developedin Phase I and develop an operating prototype system. A system that combines GPS with digital terrain data for navigation and terrain avoidance will be attractive to civil and commercial aircraft, enhancing safety, especially in mountainous terrain bad weather."