First SLS Launch Slips to August 2022 or Later

The Space Launch System failed another test sothe earliest possible launch is August. The next wet rehearsal test is hoped to be early June.

At a May 5 briefing, NASA officials said they had made progress on two problems with the SLS and its mobile launch platform discovered during three attempted wet dress rehearsal (WDR) operations in April. They replaced a helium check valve in the rocket’s upper stage. They found a small piece of rubber in the valve that prevented it from closing. A hydrogen leak detected at the pad was likely caused by bolts on a gasket that has loosened up.

The total spent on SLS will be about $27 billion if it launches in August, 2022. $23 billion in 2021 dollars have been spent for development from 2011 to 2021. They are spending at a rate of $2.5 billion per year. On top of this, the costs to assemble, integrate, prepare and launch the SLS and its payloads are funded separately under Exploration Ground Systems, currently at about $600 million per year. Six years of working to assemble and prep for launch will be about $2 billion if they launch in August 2022. This also does not include funds for the Orion capsule development or about $10 billion for the preceding Constellation project which was using pretty much the same contractors working to reconfigure Shuttle era components and technology. they were re-arranging some Shuttle parts into an Apollo rocket-style configuration.

In November 2021, a new NASA Office of Inspector General audit estimated that the first four launches of SLS would cost $2.8 billion. $2.2 billion plus $568 million for Exploration Ground Systems. These would be for the Artemis program so the payload would cost $1 billion for Orion and $300 million for the ESA service module. This would be a budgeted $4 billion per SLS launch.

Ancient RS-25 Engines

Designed and built by Aerojet Rocketdyne of Sacramento, California, RS-25 engines helped power the space shuttle over three decades through 135 missions, accumulating more than 3,000 starts and one million seconds of ground test and flight operation time. The SLS Program has an inventory of 16 RS-25 flight engines from the Space Shuttle Program to support the first four SLS missions.

Each shuttle used three RS-25 engines, but each SLS mission requires four. While shuttle engines operated at 104.5 percent of rated thrust, each SLS engine will operate at 109 percent thrust – approximately 512,000 pounds of vacuum thrust. Originally developed for the Space Shuttle Program, the RS-25 was updated five times during the shuttle program to improve service life, durability, safety, and performance. SLS takes advantage of that technology investment and experience. Fourteen flown engines and two new engines from the shuttle program will be adapted for use on the first four SLS missions.

SpaceX has launched the Falcon 9 seventeen times so far this year. SpaceX Starship orbital test has been delayed by the FAA environmental review. While SpaceX is waiting they have changed out the booster and first stage to updated versions. They are now using new Raptor 2 engines.