Laser-Based Mass Flow Rate Sensor Onboard HFiRE Flight 1

Abstract

The development of an optical mass capture sensor system for use onboard hypersonic flights under the HIFiRE program is discussed. The inlet flow velocity is determined directly from the Doppler shift of oxygen absorption lines centered about 760 nm with the use of wavelength modulation spectroscopy for high-sensitivity measurements. A compact, low weight and volume design are required for a flight-ready sensor system having minimum power consumption. The required tests for qualifying the instrument for flight are discussed. The sensor system completed successfully all qualification tests, and is on standby for launch 2010.