In order to achieve mission effectiveness in the present threat environment, military helicopters and small Unmanned Aerial Vehicles (UAVs) operations are focusing on low-level or nap-of-the-earth flying. This is the tactic of employing the aircraft in such a manner as to utilize the terrain profile to enhance survivability by degrading the enemyâs ability to visually, optically or electronically detect or locate the aircraft. In these scenarios, radar is normally required to maintain the aircraft flight at a present altitude above the terrain. Since the adoption of this philosophy, the incidence of obstacle strike accidents has grown. The main restrictions for low-level navigation and terrain following operations with helicopters and UAV are due to adverse weather conditions. Low visibility is the main reason that prevents flight/ground crews from safely controlling the aircraft and from identifying possible obstacle collision hazards. The first laser experiment directed towards a laser obstacle detection and avoidance system started in 1965 with a Nd:YAG laser.
Last date updated on June, 2021