After an hour delay because of a glitch with the ground computer system, the booster fired horizontally for just over two minutes at a test site in Utah, burning through 5.5 tons of propellant per second, shooting flames out at three times the speed of sound, with temperatures that were expected to reach 3,700 degrees. The booster test comes ahead of the rocket's first mission, planned for 2018, when it would launch the unmanned Orion spacecraft on a three-week journey that would take it around the moon.
After the test, officials at NASA and Orbital ATK, the Dulles-based contractor that built the booster, said it was a success.
“Seeing this test today, and experiencing the sound and feel of approximately 3.6 million pounds of thrust, helps us appreciate the progress we’re making to advance human exploration and open new frontiers for science and technology missions in deep space,” William Gerstenmaier, associate administrator for the Human Exploration and Operations Mission Directorate at NASA, said in a statement.
"That rumble that you get is awesome," Charlie Precourt,vice president and general manager of Orbital ATK’s Propulsion Systems Division, said on NASA TV. "We made it through exactly what we were looking for."
Combined, a two-minute test firing of the rocket's boosters, the largest and most powerful ever designed, would generate enough energy to power 92,000 homes for a day, NASA said.
The test follows a successful launch in 2014 of the Orion spacecraft, which flew further than any vehicle designed for humans had gone in more than 40 years. Ultimately, NASA plans to use the SLS to launch to Mars, but there have been some in Congress who are pushing the agency to return to the moon instead.
"This morning was a really super day," said Alex Priskos, manager of NASA's SLS Boosters Office. "It was a fantastic test." He said the problems with the ground computers that led to the delay "had nothing to do with the motor."