NASA yesterday awarded ULA the contract for providing SLS its upper stage after the Artemis-3 mission using the Centaur-5 upper stage that was developed for the company’s Vulcan rocket.

In its procurement statement, NASA said its intention is to issue a sole source contract to ULA, meaning it’s the only upper stage being considered for this new iteration of the SLS rocket. An eight-page supporting document from NASA’s Marshall Space Flight Center (MSFC) in Huntsville, Alabama, was published to document the reasoning for its decision.

Among the stated reasons are the decades-long heritage of the RL10 engine, which has matured over time; the ability of the Centaur 5 to use the interfaces available on the Mobile Launcher 1 (ML1) along with the propulsion commodities of liquid oxygen and liquid hydrogen; and the experience of ULA’s teams working with NASA’s Exploration Ground Systems (EGS) at the Kennedy Space Center and elsewhere in the country.

They also noted that with the Centaur 3 upper stage achieving certification to launch humans as part of the Commercial Crew Program, there are a lot of common features with the Centaur 5.

The decision relieves NASA from wasting more money on the Mobile Launcher-2, which has been disaster. The contractor Bechtel has gone over budget — from $383 million to $2.7 billion — and is so behind schedule it is still unclear now whether it will be ready by 2029, a decade after the contract was awarded.

It also relieves NASA of spending more money on its own upper stage, which has as much a disaster.

Instead, this deal is an example of Isaacman doing the right thing. Rather than have NASA design and build its own upper stage, he is buying the product — almost literally off-the-shelf — from a commercial rocket company. He should expand this effort, and consider other private rockets, such as Falcon Heavy, to replace SLS itself.

Now Isaacman should consider suing Bechtel for fraud and incompetence, to try to get back some of the money it wasted.