Shorter than expected
NASA planned for the rocket’s four RS-25 engines to fire for a little more than eight minutes, but the engines shut down in a little more than one minute. Teams are now investigating what happened to fix the issue for future trials.
The test saw 733,000 pounds (332,483 kg) of liquid oxygen and liquid hydrogen loaded and the engines ignited. The core stage measures 212 feet (64 mt) and generated 1.6 million pounds (725,747 kg) of thrust.
"Saturday’s test was an important step forward to ensure that the core stage of the SLS rocket is ready for the Artemis I mission, and to carry crew on future missions,” said in a statement NASA Administrator Jim Bridenstine, who attended the test. “Although the engines did not fire for the full duration, the team successfully worked through the countdown, ignited the engines, and gained valuable data to inform our path forward.”
The final test
The hot fire is the final test of the Green Run series that began in January 2020. Each test built upon the previous test with increasing complexity to evaluate the systems of the stages. Despite the hot fire test being cut short, NASA still considers it a success.
“Seeing all four engines ignite for the first time during the core stage hot fire test was a big milestone for the Space Launch System team,” said John Honeycutt, the SLS program manager at NASA’s Marshall Space Flight Center in Huntsville, Alabama. “We will analyze the data, and what we learned from today’s test will help us plan the right path forward for verifying this new core stage is ready for flight on the Artemis I mission.”