Hypergolic Fuel Leak Sensor

Long range interceptor missiles rely on divert and attitude control systems (DACS) powered by liquid hypergolic propellants, a fuel and an oxidizer. Specifically, the present generation of SM-3 missiles employs monomethylhydrazine (MMH) and nitrogen tetroxide (NTO). Sensors, able to detect<50 ppm of these propellant vapors in their transport, storage, and deployment canisters, are needed to protect personnel and infrastructure from explosive and toxicological hazards should a leak occur within a missile. Physical Sciences Inc. (PSI) proposes to adapt our near-infrared Tunable Diode Laser Absorption Spectroscopy (TDLAS) sensors to meet this need. The TDLAS sensors are based on a mature technology platform used in our commercial natural gas leak detector products. They offer small size and power consumption, fast response, high selectivity, sensitivity, and accuracy. The Phase I effort will demonstrate that these sensors can be configured as sensitive hypergolic propellant leak alarms, and can operate reliably, unattended, with little power consumption, for extensive periods.