The short answer is: There is nothing to keep ULA from buying additional RD-180’s from NPO Energomash, if they want to continue using the Atlas V.

The long answer is: Well, let’s review the history:

2014: ULA announces plan to develop a new lauch vehicle employing U.S.-developed engines
2016: Congress reaches a compromise to allow the Air Force (now, Space Force) to set December 31, 2022 as the end date for awarding contracts to the United Launch Alliance (ULA) for Atlas V launches of national security satellites that would use RD-180 engines.
2016: Tory Bruno announces that the new launcher, Vulcan, will be human rated. [https://twitter.com/torybruno/status/770579558726668288]
2020: Bruno reverses himself on human rating: “Boeing hasn’t been certifying the Starliner capsule to fly on Vulcan, meaning the Atlas V will remain Starliner’s ride to the ISS for the foreseeable future. ULA will have the RD-180s to handle the expected pace of Starliner launches into 2028, if needed, Bruno said.​ ” [Link: https://www.bizjournals.com/denver/news/2020/08/20/united-launch-alliance-space-force-spacex-contract.html%5D

Bob’s post brings us up to today. So how to reconcile this with all that?

The first observation to make is that the federal statute only pertains to national security launches. It does not forbid NASA, or Boeing, or Amazon, or Sierra Nevada, from contracting a payload on an Atlas (or any rocket using Russian engines) after 2022.

The second observation to make is that while Bruno’s comment *sounds* definitive, it does not speak specifically to what Atlas V launches Boeing has already purchased on Atlas V. It could be that they’re set for launches on some of those Atlas V’s into the late 2020’s (it only has to launch once per year, after all). That said, I don’t know any more than you do how many of those there are.

I think what happened is that Boeing – which is both customer and 50% ULA stakeholder – decided at one point that they did not want to pay for human rating Vulcan (or at least, not a moment sooner than they have to); that it would be cheaper for the time being to fly Starliner on Atlas V, even though it is a more expensive rocket. Note that the Commercial Crew contract is fixed cost; if they did not include human rating costs for Vulcan (on top of human rating Atlas V) in the contract, Boeing has to eat that cost itself.

Hopefully Bruno will clarify just exactly what will be done with Vulcan vis-a-vis Starliner soon.

So either they will keep Atlas V around just for Starliner missions, or they’ll try to squeeze NASA (or Boeing, or both) into paying for human rating Vulcan?

Edward: The interview was done for the article at the link. They did not provide a link to the interview itself.

Robert,
There is no link to the interview.

Even though the first article was posted a year ago, ULA is still in the same predicament now, waiting for the BE-4.