{"project":{"id":16692,"lastUpdated":"2018-10-10","title":"Nitrous Oxide Ethane Ethylene Engine, Phase I","status":"Completed","startDate":"May 2013","endDate":"Nov 2013","description":"The Nitrous Oxide Ethane-Ethylene (NEE) engine is a proposed technology designed to provide spacecraft with non-toxic non-cryogenic high-performance propulsion. With the NEE engine, nitrous oxide is used as an autogenously pressurizing oxidizer, and a mixture of ethane and ethylene is used in the same manner as fuel. Initially, the ethane and ethylene mixture have the same vapor pressure as the nitrous oxide. By utilizing the autogenous pressurization capabilities of these propellants instead of an additional pressurization system greater system simplicity and reliability can be attained. Achievable specific impulse with pure N2O is about 315 s, which can be raised above 325 s by dissolving some O2 in the N2O. Catalytic ignition can be achieved by using a ruthenium reactor to exothermically dissociate N2O. Since both propellants can exist as a liquid in the same temperature range, no thermal separation is required, and the two propellants can be stored together in compact common bulkhead tanks, and freezing is not an issue down to -90C. Pioneer Astronautics has demonstrated monopropellant nitrous oxide thrusters with a specific impulse of 190 s. Using such nitrous oxide monopropellant engines for low thrust RCS together with the NEE for ??V and larger thrust reaction control propulsion, it will be possible to build spacecraft propulsion systems that are completely storable and non-toxic, with only two propellant fluids required. In the proposed program, we will demonstrate a NEE engine.","benefits":"NEE propulsion would have many commercial spacecraft applications. The NEE would enable the first non-toxic storable stage, and as such would find many customers who would value it as a cost-effective alternative to the current choice of toxic hypergol or cryogenic propulsion. With its high performance and indefinite space storability, the NEE engine would be ideal as a lunar ascent/descent reaction control propulsion system. The NEE is particularly advantageous if used on manned spacecraft such as the lunar ascent/descent vehicle, the MPCV, or vehicles used in conjunction with manned spacecraft (such as free-flying inspection telerobots used in support of the ISS or MPCV), as in that case the N2O can be used for NEE bipropellant ??V propulsion, nitrous oxide monopropellant low-thrust RCS, and to provide a storable reserve supply of crew breathing gas.","technologyMaturityStart":"3","technologyMaturityCurrent":"3","technologyMaturityEnd":"4","responsibleProgram":"SBIR/STTR","responsibleMissionDirectorateOrOffice":"Space Technology Mission Directorate","leadOrganization":{"name":"Marshall Space Flight Center","type":"NASA Center","acronym":"MSFC","city":"Huntsville","state":"AL"},"workLocations":["Alabama","Colorado"],"programDirectors":["Jennifer L Gustetic"],"programManagers":["Carlos Torrez"],"projectManagers":["Jonathan H Williams"],"principalInvestigators":["Robert Zubrin"],"libraryItems":[{"id":4694,"title":"Final Patent/New Technology Report","type":"Link","description":null,"externalUrl":null,"publishedBy":null,"publishedDate":null,"files":[]},{"id":2930,"title":"Project Image","type":"Image","description":"Nitrous Oxide Ethane Ethylene Engine","externalUrl":null,"publishedBy":null,"publishedDate":null,"files":[{"id":3932,"url":"https://techport.nasa.gov/file/3932","size":21203}]}],"closeoutDocuments":["https://techport.nasa.gov/file/15055"],"supportingOrganizations":[{"name":"Pioneer Astronautics","type":"Industry","acronym":null,"city":"Lakewood","state":"CO"}],"primaryTas":[{"id":3252,"code":"2","name":"In-Space Propulsion Technologies","priority":null},{"id":3423,"code":"2.1","name":"Chemical Propulsion","priority":null},{"id":4083,"code":"2.1.1","name":"Liquid Storable","priority":null}],"additionalTas":[]}}