NASA’s Bill Hill talks SLS scheduling and Exploration Upper Stage

Scott Johnson

NEW ORLEANS, La. — On Tuesday, Jan. 26, while at NASA’s Michoud Assembly Facility (MAF), SpaceFlight Insider (SFI) had the opportunity to speak with Bill Hill, the agency’s deputy associate administrator for Exploration Systems Development, and Steve Doering, the Space Launch System (SLS) Core Stage manager, and obtain an update on a few key SLS issues:

SpaceFlight Insider: What is the latest, up to the minute, status of the Exploration Upper Stage (EUS)?

Hill: “I’m about to sign a directive to kick the entire system off, to put it into the baseline for EM-2. I should sign it next week. I was looking at it yesterday and I’ve got a couple of tweaks to do.

“SLS will go off and continue toward preliminary design review in the fall.

“Our friends at GSDO [Ground Systems Development and Operations] in Florida have to take a look at what they have to do to support it. Between EM-1 and EM-2, they’re going to have to basically cut the top off the launch [tower], make it taller, move everything up. They also, and you can talk to Mike [Bolger, GSDO program manager,] about it, but they also probably have to increase our liquid hydrogen storage capability to support both the core stage and upper stage, and multiple things.

“And then [there are] some tweaks that Orion may have to do. I’m not sure. They have to take a look the loads and so forth.”

SpaceFlight Insider: What effect, if any, will flying the EUS on EM-2 have on the intention to fly crew on EM-2?

Hill: “We have no requirement to fly it without [a] crew . . . . It’s all speculation. We flew shuttles [the] first time with [a] crew.”

Doering: “We’ll take the Exploration Upper Stage and we will fire it, just like we’re doing with the core stage, prior to its flight, to qualify it . . . . The trade study is ongoing as to what test stand across the country, across the agency, we will use. There are about six options that are under study.”

SpaceFlight Insider: Can you comment on the possibility of an additional SLS mission, to Europa or otherwise, flying between EM-1 and EM-2?

Hill and Doering: “All speculation.”

Hill: “I don’t think Europa’s going to be ready in ’22 like folks think they are. There’s some speculation, because of the Orion commitment for ’23 that we have on the books, that if Europa came in in ’22, we would fly that first. We are still driving for EM-2 toward August of ’21, all three programs [- SLS, Orion, and GSDO].”

Doering: “The other part of that speculation had to do with the same speculation, speculation on speculation. Y’all said since we’ve got EUS, we can’t fly crew on it the first time, therefore EM-2 now has to be unmanned, therefore they’ll fly something else, so it’s all part of that same pattern of speculation.”

SpaceFlight Insider: Can you comment on the recent Aerospace Safety Advisory Panel (ASAP) report and the safety concerns related to driving toward a 2021 EM-2 launch when there’s zero confidence in that date?

Hill: “I’m very confident we can make ’21. That was, the ’23 date, was based on a probabilistic model that models the probability of a certain risk occurring at a certain time. One of the things that the modelers put in that model, for ’23, was that Orion would have to, that the Europeans wouldn’t bring a European service module for EM-2, that we’d have to have Lockheed build it from scratch. It was about a three or four hundred million dollar hit, and because of that, it pushed some of that out to ’23.

“To me, it’s a probabilistic thing. To me, what it basically says is if all those risks occur, yeah, you’re going to be out there. What it doesn’t account for is we have management that manages against those risks, that mitigate those risks. And so, it doesn’t account for what we can do to bring it back to the left. And we believe we can still make it in ’21.”

SpaceFlight Insider: There’s been some indication that the European service module may be driving possible SLS delays. What is the status of the service module?

Hill: “We think, the Europeans have to go back to what they call the Ministerial to get additional funding for EM-2. That occurs, I believe, in November of this year, and it occurs every two years, so they’ve got to get everything right. So that occurs in November of ’16. They’ve got to get extra funding.

“We’re also going to get them to take a look at maybe building some additional ones that we’re going to be in negotiations with them to see if that is a possibility. And they may build those as a true partner and provide those at no cost to NASA.”

SpaceFlight Insider: The current agreement is for the Europeans to supply only one service module, for EM-1?

Hill: “Basically, for the one with piece parts for the second.”

The first SLS launch, Exploration Mission 1 (EM-1), an uncrewed test flight of the Orion capsule around the Moon, is scheduled for 2018. The first crewed flight, Exploration Mission 2 (EM-2), is scheduled for no earlier than 2021 and no later than 2023.