NASA’s moon rocket test Saturday didn’t go as planned

This final test of NASA’s SLS megarocket was needed to launch the first uncrewed mission in the Artemis program – Artemis 1 – by the end of 2021. Now the program’s schedule is uncertain.

Huge cloud of smoke or steam pouring from a multi-story test stand.

View larger. | The core stage for the 1st flight of NASA’s Space Launch System rocket is seen in the B-2 Test Stand during a hot fire test January 16, 2021, at NASA’s Stennis Space Center near Bay St. Louis, Mississippi. Image via NASA.

A planned eight-minute test firing of the four engines of NASA’s Space Launch System (SLS) – a megarocket more powerful than the Saturn V that propelled the Apollo astronauts to the moon – did not go as planned on Saturday, January 16, 2021. The test was conducted at NASA’s Stennis Space Center in Mississippi. The rocket is the one meant to launch the next man and first woman on a return to the moon by 2024 in NASA’s Artemis program. The four engines on the booster stage were supposed to fire for the eight minutes they’d need to fire during an actual moon mission launch. Instead, the engines shut down after just 67 seconds.

In a January 19 update, NASA said that after analyzing initial data from the test, the agency has determined the rocket’s engines and other hardware remain in excellent condition. NASA said:

The shutdown after firing the engines for 67.2-seconds on Jan.16 was triggered by test parameters that were intentionally conservative to ensure the safety of the core stage during the test.

NASA has not yet announced whether or not another test will be performed in the coming weeks. Read more specifics about the results of NASA’s analysis of the moon rocket’s test at the Artemis mission blog.

NASA Administrator Jim Bridenstine, who attended the January 16 test, said:

Saturday’s test was an important step forward to ensure that the core stage of the SLS rocket is ready for the Artemis 1 mission [an uncrewed test mission whose launch had been planned for later this year], and to carry crew on future missions. 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.

Read more from NASA about the specifics of the January 16 test of NASA’s SLS megarocket

The January 16 test – called a hot-fire test – was meant to be the culmination in a series of tests for the SLS megarocket. Originally scheduled to take place in early to mid-November 2020, this final testing was needed to keep its schedule on track for the rocket’s debut launch on the uncrewed Artemis 1 mission in mid-to-late 2021 and, ultimately, to the final crewed launch to the moon in 2024.

Although the SLS testing series started with a successful modal test – a kind of vibration testing – conducted in January 2020, the ongoing coronavirus pandemic then slowed the testing process. On-site work at Stennis was stopped by NASA leadership in March 2020, around the same time many in the U.S. began working from home, due to the pandemic. The center began reopening slowly in mid-May, and the second SLS test was completed on the core stage (the orange “body” of the rocket) in late June.

That test ensured that the software and other electrical interfaces involved in the rocket and the testing stand work properly.

Ground-level view of 4 large rocket engines firing downward.

View larger. | In the January 16, 2021, test, the 4 RS-25 engines fired for a little more than a minute and generated 1.6 million pounds of thrust. Image via NASA.

The rocket has since undergone and passed the next four steps of what is called the “green run” series:

– Test 3, in which engineers inspected all the safety systems that shut down operations during testing. During this test, they simulated potential problems.

– Test 4, the first test of each of the main propulsion system components that connect to the engines. Command and control operations were verified, and the core stage was checked for leaks in fluid or gas.

– Test 5, in which engineers ensured the thrust vector control system can move the four engines and checked all the related hydraulic systems.

– Test 6, which simulated the launch countdown, including step-by-step fueling procedures. Core stage avionics were powered on, and propellant loading and pressurization were simulated. The test team exercised and validated the countdown timeline and sequence of events.

A close-up of a single engine firing with white gases or steam pouring from it.

The hot fire is the final test of the Green Run test series, a comprehensive assessment of the Space Launch System’s core stage before launching the Artemis I mission to the moon. Image via NASA.

After the January 16 hot fire test, engineers had planned to refurbish the core stage and configure it for its journey to NASA’s Kennedy Space Center in Florida, where still more tests await the core stage.

Now – with the Biden administration coming into office on January 20, 2021, and with the failure of the January 16 test – the scheduling of the Artemis program is uncertain.

Read more: How will the U.S. space program fare under President Joe Biden?

Chart with list of 8 tests and labeled diagram of SLS rocket sections.

This graphic illustrates what the 8 parts of the green run is meant to test, as well as the individual components of the SLS Core Stage (orange rocket body). Image via NASA.

Bottom line: The failure of NASA’s SLS megarocket hot-fire test on January 16, 2021 is a clear setback for NASA’s Artemis program. But NASA said that after analyzing initial data from the test, the agency has determined the rocket’s engines and other hardware remain in excellent condition.

Via NASA

Lia Rovira