Three-axis Low Airspeed, Low-Cost Air Data Sensor for Rotorcraft

A three-axis low airspeed, low-cost air data sensor (3x-LAS) using hot-film gages will be developed for helicopter applications. Low speed flight consisting of hover, forward, rearward, and lateral motion impacts important flight-operation problems involving vehicle performance, flight stability and control, structural load, fatigue life, and pilot action. This segment of the helicopter flight is critical in terms of safety and safely expending the maneuvering envelope during maneuvers such as approach, rapid descent, hover, sideward, and rearward flight. Low airspeed measurement is also important on attack helicopters for low speed targeting. Traditional airspeed systems experience serious limitations in accuracy at air speeds below 40 knots. The proposed innovation, based on the use of high-frequency response hot-film gages will measure airspeed all the way to zero knots. The 3x-LAS will be developed both as an embedded, non-intrusive system and a stand-alone probe which could be easily retrofitted with minimal calibration requirements and without having to make significant structural changes to the vehicle. 3x-LAS will be ruggedized to deal with harsh environment for an acceptable all-weather operation. Other applications include aerospace and ground vehicles, submarines, ships, and measurements in the atmosphere, ocean, and in internal flows.