Pratt & Whitney Rocketdyne has announced the first firing of the J-2X, the liquid fuel rocket that will power the second stage of the Space Launch System.

The firing, conducted at the Stennis Space Flight Center, lasted 1.9s. The test was successful, said Walt Janowski, P&W Rocketdyne J-2X programme manager. "All the measured data looks pretty good, all the hardware inspections post-test look pretty good," he said.

A prior test attempt, conducted 7 July, was automatically aborted when the computer detected a problem. The problem was due to a software logic fault, Janowski said. The engine is being inspected and reset for a test in the week of 18 July.

There are seven J-2X engines slated for the test program. The second is scheduled for completion in early 2012.

 J-2X Rocketdyne


J-2X, a significantly improved variant of the J-2, which powered Saturn rockets during the Apollo program, generates 294,000lbs of thrust. Fuelled by liquid hydrogen and liquid oxygen, the engine is capable of stopping and starting in space, making it ideal for deep space missions.

The J-2X was initially developed as part of the Constellation programme, to power the upper stage of the Ares rocket series, but development continued after Constellation was cancelled.

Source: Flight International