Launch costs should matter ... "In view of the current availability of a significant number of commercial launch vehicles with proven payload capabilities, as well as the industry's progress in providing a launch vehicle with significantly greater lift capabilities, the Biden administration should reconsider the need for the SLS during its annual budget review," writes Abbey, who is now a senior fellow in space policy for Rice University.I know that it may seem that I'm picking on the SLS, but it seems to be the embodiment of what I consider "old space." The program was started for the political benefit of spreading money around rather than for a specific mission, and was changed over and over again as projected missions changed. Now, approaching five years late, the dates on their schedule appear wildly optimistic.
Last January, 2020, NASA and Boeing delivered the first (partially) completed SLS core stage to Stennis Space Center, where an unused half-century-old test stand was refurbished for several hundred million dollars for a single major objective: the Green Run.
The Green Run amounts to a full-duration (eight minute) static fire of the SLS core stage: the main liquid-fueled booster and its four repurposed Space Shuttle Main Engines (SSMEs). Prior to that ignition and burn test, Boeing and NASA would put the rocket through a number of other basic tests for the first time, including power-on, modal analysis, and a wet dress rehearsal (a static fire without the ignition). If you watch SpaceX at Boca Chica, this is what you see going on when a new Starship prototype goes to the test stand. They take a month, but it's a much smaller vehicle.
At the time of arrival of the SLS core at Stennis, ever zealously overconfident NASA and Boeing officials talked about the Green Run like it was a small, moderately inconvenient hurdle set in front of their flawless SLS rocket. A Boeing official estimated that the rocket would complete the test campaign and be ready to ship to Kennedy Space Center by the middle of last year!
Of course, that didn't happen. A full year of apparently unanticipated issues with the vehicle led to January's static fire test that ended with an aborted test 62 seconds into a planned eight minute firing, about 13% of the desired run. After an embarrassingly long time before they announced they would actually insist on a re-test, NASA and Boeing discovered an engine valve issue for the second time (the first was last November), requiring at least another 4-6 weeks to repair. That valve was fixed on March 3rd, setting up a second static fire attempt no earlier than March 16th.
SLS-1 Core at Stennis Space Center. NASA photo.
Here's the big issue. This SLS core is intended to fly the first, unmanned, orbital Artemis mission. Hilariously, NASA and Boeing are still sticking to their schedule fantasy and continue to parrot the party-line that SLS's Artemis-1 launch debut with this prototype is still on track to launch in "November 2021." That date was set almost a year before the SLS Green Run schedule delays ballooned by at least nine months. If NASA and Boeing are lucky and there are no more failures that eat months at a time, Artemis-1 might fly by the fall of 2022.