’s J-2X upper-stage engine ran through a 500-sec. hot-fire test Nov. 9, achieving full duration for the terminated Ares I crew launch vehicle it was designed to power and passing a crucial hurdle for the heavy-lift Space Launch System (SLS) that will use it instead.
“Based on a quick look, it performed exactly as we expected it to,” said Mike Kynard, SLS engines element manager at the, after the test at NASA’s Stennis Space Center in Mississippi. “If we find issues we’ll take care of it; first look, it ran great.”
The test came less than two weeks after another one cut short at 140 sec. because of what Kynard termed “human error” in setting software redlines to prevent damage to the sole J-2X development engine. Even so, the earlier test demonstrated that the engine was ready for a full-duration burn and cleared the way for the Nov. 9 test.
Based on the upper-stage engines developed for the Saturn V Moon rocket, the J-2X is designed to produce 294,000 lb. of thrust on ascent to orbit, and 242,000 lb. of thrust to move an upper stage beyond low Earth orbit.
The test was the eighth in the series with the engine designated 10001. Each development engine is built to withstand 28 tests.
Four complete engines are scheduled for the development-test series, plus an assessment with a powerpack article that includes the gas generator and turbomachinery.
During the test, the engine burned some 100,000 gal. of liquid hydrogen and 30,000 gal. of liquid oxygen, at a one-time cost Kynard put at $350,000.