The development of a nitrous oxide/ hydroxl-terminated polybutadiene (N20/HTPB) hybrid rocket motor technology database is proposed. For small rocket systems, N20 based hybrids potentially offer higher performance than liquid oxygen based hybrids for less complexity and cost. Storable and non-cryogenic, N20's advantages stem from its high (750 psia) vapor pressure at room temperature, allowing the oxidizer feed system to operate in a "blowdown mode". As such, a pressurization system is not required, increasing stage reliability. As a first step, this investigation is focused on acquiring the data necessary to fully quantify the behavior of N20 at a large scale. Blowdown tests will be conducted for motors in the 10,000 lb thrust class at NASA Stennis Space Center's (SSC) Component Test Facility. SSC will perform the necessary modifications to the CTF for this effort, and will assist in the testing. In addition, design work will be done for both a 10,000 lb and a 40,000 lb thrust N20/HTPB motor, to be tested in the same location in Phase II.Hybrid rocket propulsion technology is generally well suited for a variety of space launch applications, being lower cost than either solid or liquid rocket motors. In particular, nitrous oxide based hybrids show a potential cost, reliability and performance advantage over LOx based hybrids for small systems. As such, commercial applications for N20 technology include upper stages, sounding rockets, medium sized strap-on boosters and core stages for small launch vehicles.hybrid propulsion, nitrous oxide oxidizer, testingPhase 2 conversion