The Space Launch System rocket core stage is shown installed on the top-left side of the B-2 Test Stand at NASA’s Stennis Space Center.
Enlarge / The Space Launch System rocket core stage is shown installed on the top-left side of the B-2 Test Stand at NASA’s Stennis Space Center.

NASA

In a fairly anodyne update on NASA’s “Artemis” blog published Wednesday, the space agency’s new chief of human spaceflight laid out progress made on key hardware programs.

“Already within my short time on the job, NASA is checking-off key milestones and marching swiftly toward Artemis I,” wrote Kathy Lueders, who moved into the job after leading the Commercial Crew program. “That mission, the first uncrewed flight test of our powerful Space Launch System rocket and Orion spacecraft, is just a little more than a year away from launch.”

Lueders next discussed preparations for a “Green Run” test of the SLS rocket’s core stage this fall, possibly by the end of October. This test will take place at Stennis Space Center in southern Mississippi, during which engineers for NASA and the core state contractor, Boeing, will ignite the clamped-down rocket’s four main engines and fire them for eight minutes to simulate a launch and ascent into space.

After discussing this and other details, Lueders then rather casually let it slip that, “NASA also aligned the development costs for the SLS and Exploration Ground Systems programs through Artemis I and established new cost commitments.” The new development cost for SLS rocket is $9.1 billion, she said, and its budget for the initial ground systems to support the mission is now $2.4 billion.

Left unsaid: This represents a 33-percent increase for the rocket since 2017, when a “re-plan” of program estimated development costs for the rocket, including a single test flight, would be $7.17 billion. (This was detailed in a US General Accounting Office report published nearly a year ago.) This figure represents only direct development costs. NASA has received more than $20 billion from Congress since 2011 for SLS development and related activities.

At the time of the “re-plan” in 2017, NASA established a “December 2019-June 2020” date for the first test launch of the SLS rocket. This was a delay from earlier plans to launch it by the end of 2017.

In her update, Lueders said she was “confident” that a November 2021 launch date for the rocket is achievable. However, she cited a few caveats to this. For one, she said, “It is still too early to predict the full impact of COVID-19.” She also said such a launch date is predicated on “a successful Green Run hot fire test.”

This latter caveat may be a rather big one. With this test, for the first time, NASA will be pushing the integrated core stage—consisting of four space shuttle main engines, large liquid hydrogen and liquid oxygen fuel tanks, as well as all the plumbing needed to control the flow of chilled fluids—for the first time. While the agency has studied independent components, ensuring they work together is a big deal.

Engineers familiar with testing large, complex systems for the first time say there is a low probability of a perfect test or a major structural failure. However, the highest probability is that NASA and Boeing discover some problems that will at least require several months to address before the core stage is deemed ready for launch.