SLS is not flying in 2020.

[tater]

This is not arguable at this point, forget Eric Berger, @_Augustus_, just read the transcript of what Bridenstine said.

The Green Run test will not even be done until 2020 (that's when it is scheduled), people know this, right? The entire point of checking to see if they needed it was that the ONLY way to launch in 2020 was to not do Green Run.

This is not new news, we've all known that 2020 was entirely off the table as soon as they decided to do the Green Run test (which they had planned to do anyway).

The new news from Birdenstine the other day was that even 2021 is looking marginal due to what The NASA Administrator himself said before Congress. Not what Eric Berger says about it, what Bridensine actually said.

He was clearly lowering expectations for a 2021 EM-1.

Edited July 21, 2019 by tater

[tater]

https://www.nasaspaceflight.com/2019/04/nasa-sls-green-run-em-1-schedule-risks/

The Green Run campaign is supposed to take "many months" to complete. This is not tipping it upright, then a short static fire, then launch 5 days later. It's a full testing regime of the first time they actually stick all the core stage parts together.

A low-budget version is what we have seen with the SpaceX Hopper. Sticking a real engine on something, then trying to fire it. There will be dry runs (many) to check GSE stuff, then eventually they run props through the engines without firing them, then they do a fire at some duration (unsure if they jump right to a full burn, but that seems unlikely). Since they are not hardware rich, they are likely extremely careful (also, they are NASA, so extremely careful), hence it takes months.

Previous (all overly optimistic, BTW) NASA timelines for SLS milestones had shown the Core Stage delivered to Stennis (edit:was right the first time) in December, and Green Run completion, with delivery to FL some 6 months later. Both milestones had a 2-4 month schedule risk associated with them. (same people made this chart that had it flying 4 years ago, so YMMV)

Edited July 21, 2019 by tater

[tater]

Here we go:

https://www.nasaspaceflight.com/2016/09/the-green-run-sls-milestone-static-fire/

Quote

Green run schedule:

The B-2 test stand work is to get ready for a major development milestone for the SLS Core Stage, the Green Run test, which will essentially fly the Core Stage in place on the test stand through a nominal, eight-minute launch and ascent.

Green Run test activities will involve several firsts, including the first cold flows, the first full tanking, and the first hot fire of the four RS-25 engines integrated with the Core Stage propulsion system.

Given all the firsts, the plan is for the Core Stage to be at Stennis for several months.

“We still expect to see the Core Stage for September 2017 arrival and we expect to have the Core Stage anywhere between six to eight months,” Mr. Martin said.

 

[tater]

Also, I apologize, @_Augustus_, for any contribution to taking your thread off topic. Generally I post news about SLS to the thread, and while I don't mean to attack it so much... it's just so easy it's hard to avoid. The recent Bridenstine statement was pretty shocking to me, I was fully expecting mid 2021, now that seems unlikely, and that news derailed the thread.

Any mods ( @Vanamonde )  could move the relevant off topic posts to this thread, if they like.

Edited July 21, 2019 by tater