via extremetech:
NASA’s cost estimates at each stage have been very optimistic, and the GAO objects to the agency’s decision to monitor cost via the five-year production and operations cost estimate. The GAO report says these are poor tools to control costs, and NASA hasn’t even been consistent about updating the five-year estimates.
So far, NASA has spent $11.8 billion developing the SLS. The 2024 budget proposal includes another $11.2 billion to see the program through 2028. Will that be enough? The GAO says, no, probably not. A previous report by NASA’s inspector general suggested the $2 billion launch cost for each Artemis mission was unrealistic, and the real number was closer to $4.1 billion.
The Artemis program has suffered from numerous delays, and the report says that NASA has not been accounting for how these schedule changes affect costs. The SLS and Orion capsule contain components built all over the US (in a lot of influential congressional districts, naturally). Even minor changes cause logistical challenges and ballooning costs. However, the GAO says that at least one NASA official claimed additional SLS delays would not impact the bottom line, which seems hard to believe. On the other hand, NASA’s leadership did admit that the SLS is too expensive to support the lunar program as currently envisioned.
To be fair, NASA never wanted SLS. It’s a frankenrocket cobbled together by congresscritters eager to support existing jobs at existing contractors, and that was somehow supposed to save money by repurposing reusable Space Shuttle engines — designed five decades ago — into disposables ones.