[dotnet00]

The diversity argument does ring slightly hollow when iirc Boeing has only made two Starliners and it only has enough rockets for the 6 missions in the contract.

Basically they're set up to have one capsule in refurb while the other is at the station, and once the 6 Atlas V's are spent, someone has to cough up the money to do the stack of paperwork for crew rating the combo of Starliner and Vulcan.

[adolph]

> do the stack of paperwork for crew rating the combo of Starliner and Vulcan.

Or/and Falcon 9!

Starliner is designed for compatiblity with . . . Falcon 9, and Vulcan Centaur.

https://en.wikipedia.org/wiki/Boeing_Starliner

[dotnet00]

Putting it on Falcon 9 would not be ideal since then you're back to having a single point of failure in terms of preventing crewed launches by the US. Plus, considering that they don't exactly like SpaceX, while being half of what formed ULA...

[walkabilitee]

In case anyone asks, "why don't they just build more Atlas V rockets," it's because they rely on Russian engines which have been phased out due to politics:

https://en.wikipedia.org/wiki/RD-180

[dotnet00]

Plus, the production lines for Atlas V have already been retooled with those for Vulcan, so even if they did have the engines, they couldn't make the rockets.

IIRC ULA did have a license to manufacture their own domestic RD-180s (or was considering getting it), but the factory for those would've been very expensive and not worth it with Vulcan in its early design stages.

[panick21_]

I don't think the line has been retooled. They still have to build a number of Atlas 5s for Amazon. They don't have all of those in storage.

[dotnet00]

That's a very good point, I could've sworn Tory Bruno had said that the line had been retooled and all the remaining cores were in storage, but the closest tweet to that seems to be referring to having the engines in storage.

[panick21_]

I think he did say the line was retooled, but the factory is used for different rockets at the same time. The Vulcan and the Atlas were always in production at the same time.