Beating Heart of J-2X Engine Finishes Year of Testing by Staff Writers

The powerpack assembly burned millions of pounds of propellants during a series of 13 tests totaling more than an hour and a half in 2012. The testing team set several records for hot-firing duration at Stennis test stands during the summer.

NASA on Thursday took another step toward human exploration of new destinations in the solar system. At the agency's Stennis Space Center in Mississippi, engineers conducted the final test-firing of the J-2X powerpack assembly, an important component of America's next heavy-lift rocket.
The J-2X engine is the first human-rated liquid oxygen and liquid hydrogen engine developed in the United States in decades. Designed and built by NASA and industry partner Pratt and Whitney Rocketdyne of Canoga Park, Calif., the engine will power the upper stage of NASA's 143-ton (130-metric-ton) Space Launch System (SLS) rocket. The powerpack is a system of components on top of the engine that feeds propellants to the bell nozzle of the engine to produce thrust.

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