Jump to content

NASA SLS/Orion/Payloads


_Augustus_

Recommended Posts

2 hours ago, insert_name said:

NASA has announced that it plans to cancel SLS and divert funds to BFR!

NASA.gov/sls

Stop insulting those of us who like this song! /terrible joke

SLS could've been alright, but it's been delayed so much that it's not really going to help anything...

Link to comment
Share on other sites

3 hours ago, StrandedonEarth said:

well, for the long run it would make sense to have things in semi-mass-production instead of one-off custom jobs, just like the multiple MER's, and how the next Mars rover is based on MSL.

Why not use a commercial communication satilite, it would be cheaper and wouldn't need all the stuff that the station propulsion module would need (power for habitats, docking hardware etc.) also it could be launched on a cheaper LV than the SLS, or possibly just use an existing satellite

Link to comment
Share on other sites

3 minutes ago, insert_name said:

Why not use a commercial communication satilite, it would be cheaper and wouldn't need all the stuff that the station propulsion module would need (power for habitats, docking hardware etc.) also it could be launched on a cheaper LV than the SLS, or possibly just use an existing satellite

Well, it could be used as a relay in the interim, until they decide to dock more stuff to it. Forward thinking and all that.

Link to comment
Share on other sites

11 minutes ago, insert_name said:

Why not use a commercial communication satilite, it would be cheaper


Once it's communications relay system has been gutted and replaced with one appropriate to its mission, and it's propulsion system replaced with one suitable for going to Lunar orbit rather than GEO - I doubt it'll be as cheap as you think.  Plus it's GNC will have to be replaced, and the power system too...  and remind me why we were doing this in the first place?

There's no doubt cheaper ways to do it, but jacking up the nameplate on a commercial bus and sliding an entirely new satellite underneath isn't one of the smarter ways.

Link to comment
Share on other sites

DSG exists as something for SLS/Orion to do. Solutions that obviate SLS or Orion won't work, since they fail to meet the mission goal of providing something for SLS/Orion to do. Any New Space additions to DSG need to be of the sort that leverage SLS, so it looks like it is more important than it is, IMO.

Not tangentially, since EM-2 (the first all-up Orion flight) is ~2023, New Glenn should have been flying a couple years by then. SLS/Orion are not necessarily wed for every use case. NG could certainly loft Orion and a 3d stage, (45+ tons to LEO, and Orion CSM is 25 tons). Unsure what the 3 stage version could do with another cryo stage. So it's possible to envision a DSG architecture that uses NG to fly Orion at a might better cadence, and SLS gets used entirely for cargo. Cargo could, perhaps, be cargo on top of EUS, and Orion meets it in LEO via NG, and the lot gets sent to DSG... (course BO could buy ULA, too). Anyway, while a "new space" possible future, this is not that far fetched given current operational timelines.

Link to comment
Share on other sites

As SLS uses old Shuttle hardware for assembly, this could actually be a blessing if Rocketdyne gets those disposable SSMEs produced. Cheap materials for tanks + cheaper engines/boosters = a (somewhat) quick launch rate (and by fast, optimistically twice-thrice a year). Even with that amount, 260-390 metric tons of payload is nothing to sneeze at, and with Vulcan/New Glenn/Falcon Heavy providing the fast turnaround for useful but lighter payloads, we have a large amount of flexibility for deep space antics. Yes, you COULD take out the SLS, but that would make Congress grumpy towards "new space", and when you need to go big like serious Lunar operations (or the big goal, Mars!), you NEED that government funding, as they have a bad tendency to become monetary black holes.

Edited by T-10a
Link to comment
Share on other sites

At this point little is old shuttle hardware, except maybe the SSMEs that have likely been refurbished so much in prep for their suicidal SLS flights that they cost vastly more than just building reasonably priced engines.

The tanks are all new. Part of the problem is that SLS has to be man rated. In Constellation, the large cargo boosters were for cargo, and crew went up on a different LV (the kooky Ares 1).

Link to comment
Share on other sites

31 minutes ago, tater said:

At this point little is old shuttle hardware, except maybe the SSMEs that have likely been refurbished so much in prep for their suicidal SLS flights that they cost vastly more than just building reasonably priced engines.

The tanks are all new. Part of the problem is that SLS has to be man rated. In Constellation, the large cargo boosters were for cargo, and crew went up on a different LV (the kooky Ares 1).

Yeah. Part of why SLS is so bad is that they had to use old hardware, and just couldn't get away with it. SRBs? Redesigned. ET? Redesigned into a brand new core with a different structure and plumbing set up. The old hardware puts too many limitations on the design. Hell, even the SSMEs they have aren't all identical, and have different performance values on a per engine basis... There are even pressure issues due to the height of the tanks in the core. Not to mention that it's underpowered.

Link to comment
Share on other sites

11 hours ago, T-10a said:

As SLS uses old Shuttle hardware for assembly, this could actually be a blessing if Rocketdyne gets those disposable SSMEs produced. Cheap materials for tanks + cheaper engines/boosters = a (somewhat) quick launch rate (and by fast, optimistically twice-thrice a year). Even with that amount, 260-390 metric tons of payload is nothing to sneeze at, and with Vulcan/New Glenn/Falcon Heavy providing the fast turnaround for useful but lighter payloads, we have a large amount of flexibility for deep space antics. Yes, you COULD take out the SLS, but that would make Congress grumpy towards "new space", and when you need to go big like serious Lunar operations (or the big goal, Mars!), you NEED that government funding, as they have a bad tendency to become monetary black holes.

Congress is never going to fund a Mars mission at current NASA prices. Even going back to the moon is a stretch.

Link to comment
Share on other sites

44 minutes ago, _Augustus_ said:

Congress is never going to fund a Mars mission at current NASA prices. Even going back to the moon is a stretch.

They theoretically could, but since NASA has so many programs that take money out of the total budget, it'll never happen. NASA isn't given a pile of cash and told to go to space, they're given money that is marked for specific uses. Just the way Congress likes it...

Link to comment
Share on other sites

7 minutes ago, Bill Phil said:

They theoretically could, but since NASA has so many programs that take money out of the total budget, it'll never happen. NASA isn't given a pile of cash and told to go to space, they're given money that is marked for specific uses. Just the way Congress likes it...

Not even theoretically, since NASA really doesn't decide what gets spent on what. Unless you mean in an alternate universe where they get the 20 B$ they just got every year, and are allowed to spend it as they see fit.

Link to comment
Share on other sites

2 minutes ago, tater said:

Not even theoretically, since NASA really doesn't decide what gets spent on what. Unless you mean in an alternate universe where they get the 20 B$ they just got every year, and are allowed to spend it as they see fit.

That's exactly what I mean. If they had a money pile of 20 billion every year, they could do a Mars mission. Might take 20 years of funding, but certainly possible. Of course, reality doesn't work like that.

Link to comment
Share on other sites

Quite interesting, even though he goes on about the history of space stations. Is his statement true, that the SLS could lift the entire station onto a lunar trajectory? It even more sounds like make-work for the SLS if they deliberately launch it in pieces.

Link to comment
Share on other sites

39 minutes ago, StarStreak2109 said:

Quite interesting, even though he goes on about the history of space stations. Is his statement true, that the SLS could lift the entire station onto a lunar trajectory? It even more sounds like make-work for the SLS if they deliberately launch it in pieces.

Maybe Block 2 could, but there's not much evidence that Block 2 will ever fly. And it certainly can't when taking an Orion as well (25 tonnes).

Link to comment
Share on other sites

4 hours ago, StarStreak2109 said:

Quite interesting, even though he goes on about the history of space stations. Is his statement true, that the SLS could lift the entire station onto a lunar trajectory? It even more sounds like make-work for the SLS if they deliberately launch it in pieces.

I don't think they'd be able to get it into lunar orbit, even if that were true.

Link to comment
Share on other sites

1 minute ago, sevenperforce said:

I don't think they'd be able to get it into lunar orbit, even if that were true.

It has it own ion engines.  Why not launch into LEO, it definitely has enough DV to get to the moon.

Link to comment
Share on other sites

10 minutes ago, DAL59 said:

It has it own ion engines.  Why not launch into LEO, it definitely has enough DV to get to the moon.

Not enough thrust. High-thrust chemical engines can get from LEO to LLO with a little over 4 km/s, but an ion-based low-thrust system must spiral out slowly and much less efficiently. Costs about twice as much dV.

What they could do, I suppose, is use Block 2 to send the whole station into a lunar slingshot at just the right trajectory that the moon's gravity raises the perigee very high; that would enable a low-thrust solution to insert into a NRHO relatively fast.

Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
×
×
  • Create New...