Rotorcraft Airspeed Measurement System

To address the Navy need, Physical Optics Corporation (POC) proposes to develop a new Rotorcraft Airspeed Measurement (RAM) system. This proposed system is based on self-mixing interference in a semiconductor laser diode. The innovation in using low-power, small-sized diode lasers and in assembling diode lasers in a specific geometry coupled with a wavelength modulation technique enables the proposed system for the accurate measurement of multi-directional low airspeed of a helicopter in low altitude operations over water or ground. The RAM system combines its three-component wind speed data and the orientation and ground speed data of the helicopter from embedded Global Positioning/Inertial navigation devices to calculate the true airspeed of the rotorcraft. The proposed system will be capable of measuring airspeed in the range between 0.5 ft/sec and 1500 ft/sec. In Phase I, POC will demonstrate the feasibility of the RAM system with a velocity measuring module using a simulated rotor wash environment to measure multi-directional airspeed of a model rotorcraft in laboratory. In Phase II, POC plans to develop a rotorcraft-deployable RAM prototype to be installed and tested in a Navy helicopter or similar platform recommended by the Navy.