Congress apparently feels a need for “reaffirmation” of SLS rocket

There is a curious section in the new congressional reauthorization bill for NASA that concerns the agency’s large Space Launch System rocket.

The section is titled “Reaffirmation of the Space Launch System,” and in it Congress asserts its commitment to a flight rate of twice per year for the rocket. The reauthorization legislation, which cleared a House committee on Wednesday, also said NASA should identify other customers for the rocket.

“The Administrator shall assess the demand for the Space Launch System by entities other than NASA and shall break out such demand according to the relevant Federal agency or nongovernment sector,” the legislation states.

Congress directs NASA to report back, within 180 days of the legislation passing, on several topics. First, the legislators want an update on NASA’s progress toward achieving a flight rate of twice per year for the SLS rocket, and the Artemis mission by which this capability will be in place.

Additionally, Congress is asking for NASA to study demand for the SLS rocket and estimate “cost and schedule savings for reduced transit times” for deep space missions due to the “unique capabilities” of the rocket. The space agency also must identify any “barriers or challenges” that could impede use of the rocket by other entities other than NASA, and estimate the cost of overcoming those barriers.

Is someone afraid?

There is a fair bit to unpack here, but the inclusion of this section—there is no “reaffirmation” of the Orion spacecraft, for example—suggests that either the legacy space companies building the SLS rocket, local legislators, or both feel the need to protect the SLS rocket. As one source on Capitol Hill familiar with the legislation told Ars, “It’s a sign that somebody’s afraid.”

Congress created the SLS rocket 14 years ago with the NASA Authorization Act of 2010. The large rocket kept a river of contracts flowing to large aerospace companies, including Boeing and Northrop Grumman, who had been operating the Space Shuttle. Congress then lavished tens of billions of dollars on the contractors over the years for development, often authorizing more money than NASA said it needed. Congressional support was unwavering, at least in part because the SLS program boasts that it has jobs in every state.

Under the original law, the SLS rocket was supposed to achieve “full operational capability” by the end of 2016. The first launch of the SLS vehicle did not take place until late 2022, six years later. It was entirely successful. However, due to a variety of reasons, the rocket will not fly again until September 2025, at the earliest.

Because of the cumbersome process of building the core stage, main engines, and side-mounted boosters of the rocket, NASA’s contractors only have the capability to build one rocket a year. And that is more or less fine, because the agency doesn’t have more money to build Orions and other components for more than one crewed Artemis mission to the Moon per year.

With this legislation, then, Congress is asking NASA to find other customers for the rocket, be they from the private sector, US Department of Defense, or elsewhere. This is a bit like selling sand to a Bedouin, and NASA has already fought this losing fight in the past. The Department of Defense has said thanks, but no thanks.

NASA also sought another “customer” in its Science Directorate, offering the SLS to launch the $4 billion Europa Clipper spacecraft on the SLS rocket. However, in 2021, the agency said it would use a Falcon Heavy provided by SpaceX. The agency’s cost for this was $178 million, compared to the more than $2 billion it would have cost to use the SLS rocket for such a mission. Additionally, mission scientists had serious concerns about a “shaking” issue with the SLS rocket. This large vehicle is powered off the pad by two very large solid rocket boosters that produce significant vibrations.

SLS program officials had been telling the agency’s leadership that the torsional load—essentially a measurement of twisting and vibration—was a certain value. However, after NASA performed wind-tunnel testing, the actual torsional load value was nearly double the SLS program estimates. Accommodating for this launch stress would have required an additional $1 billion in modifications to make the spacecraft more robust.