New J-2X rocket engine ready for testing at Stennis

HANCOCK COUNTY — NASA’s new J-2X rocket engine, which could power the upper stage of the nation’s future heavy-lift launch vehicle, is ready for its first round of testing. The fully assembled engine was installed June 11 in the A-2 Test Stand at the agency’s Stennis Space Center in Mississippi.

Beginning in mid-June, the engine will undergo a series of 10 test firings that will last several months.

The test stand, which supported the space shuttle main engine project, has been modified to accommodate the J-2X engine’s different shape. In addition to the structural, electrical and plumbing modifications, a new engine start system was installed and control systems were upgraded on the stand. The liquid oxygen and liquid hydrogen transfer lines that dated back to the 1960s were replaced.

Fueled by liquid oxygen and liquid hydrogen, the J-2X engine will generate 294,000 pounds of thrust in its primary operating mode to propel a spacecraft into low-Earth orbit.

By changing the mixture ratio of liquid oxygen to liquid hydrogen, the J–2X can operate in a secondary mode of 242,000 pounds of thrust required to power a spacecraft from low-Earth orbit to the moon, an asteroid or other celestial destination. The J-2X can start and restart in space to support a variety of mission requirements.

The A-2 Test Stand originally was used to test Saturn V rocket stages for NASA’s Apollo Program. In the mid-1970s, the stand was modified from Apollo Program parameters to allow testing of space shuttle main engines.

Pratt & Whitney Rocketdyne of Canoga Park, Calif., designed and built the J-2X for NASA.

Source: Pratt & Whitney Rocketdyne