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NASA SLS/Orion/Payloads


_Augustus_
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32 minutes ago, tater said:

Yeah, for all the flak people give ULA vs New Space, ACES is a brilliant idea, using tech that they have honed to perfection already with likely the single best rocket stage ever built, Centaur. Short of huge, Apollo stacks, EOR is a way to go that minimizes risk (since all components can be tested in LEO), and maximizes the use of as many contractors as possible. This is non-trivial, because instead of making a single vehicle that is partially expensive because it uses so many contractors, it can have several vertically integrated LVs (from an mfg standpoint, not how they are stacked) that are more cost effective.

Likely the only way Vulcan can beat NG (given that they're using the same engines and ULA is paying extra) for any purpose is if they can master IVF.

KSP players take IVF for granted.

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Note also that the proposed DSG architecture has them eventually assembling an exploration vehicle at DSG for a possible Mars mission (The Deep Space Transport (DST)). That was on the proposed manifest for EM-6 as a cargo 1b, with a same year Orion flight (LOL). The year is 2027. So NASA is apparently already considering orbital assembly of a complex craft (to go to Mars in 2033, lol, EM-11), not in LEO, but around the Moon. I think EOR assembly is easier than building the DST around the Moon. If they can build a Mars craft (plan to) in 9 years around the Moon, they can make the Moon architecture use EOR assembly sooner (if for no other reason than practice).

Edited by tater
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3 hours ago, tater said:

Short of huge, Apollo stacks, EOR is a way to go that minimizes risk (since all components can be tested in LEO)

Which must be balanced against the increased risks of multiple launches, rendezvouses, and assembly operations.

TANSTAAFL no matter how hard you keep trying to handwave one into existence.

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37 minutes ago, DerekL1963 said:

Which must be balanced against the increased risks of multiple launches, rendezvouses, and assembly operations.

TANSTAAFL no matter how hard you keep trying to handwave one into existence.

I was talking crew risk, not schedule risk. More launches certainly increases the chance of a vehicle loss, no question. LEO crew vehicles, in the timeframe of SLS actually flying, will have flown many more times, both the crew vehicles themselves, as well as the launch vehicles that lift them to orbit. EM-2 I would certainly call more risky than the CST-100 first crew flight will be (Atlas-Centaur is pretty bulletproof, and it will have flown unmanned once before, all-up).

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I'm not envisioning a free lunch, BTW. I am saying that vehicles that are more cost-effective to buy for launch offer the possibility of orbital construction for substantially lower cost than SLS offers. SLS launches are literally billions (launch cost of the specific LV, plus the associated program cost which is what, 2+ B$/year, even with no flights?). Since the payloads don't yet exist, they can be designed to suit the appropriate architecture, if it matters. DSG components are all pretty small, actually, so it might not matter.

EM-3 is supposed to bring the 10t habitation module to LOP-G. The USA is 8.4m tapering to 5.4m, over around 10m of height. The images I have seen show a small hab module that is actually under 5m in diameter, and maybe 6m long. Well within the capabilities of many extant LVs to orbit. So if the first several EM missions are block 1 SLS, then EM-3 will already be 2 launches, and Orion with ICPS will have to dock with the hab module pre-placed in LEO by another LV. Oh, wait, no, that's not true, since I don;t think ICPS can take Orion AND 10t of cargo to cislunar... EM-3 was supposed to be block 1b with EUS.

So if they want a DSG to go to they'll need to fly that hab module all the way there, then rendezvous and dock not in LEO, but around the Moon.

Edited by tater
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I suggest anyone who hasn't read this NSF article do so:

https://www.nasaspaceflight.com/2018/04/nasas-dual-ml-plan-extra-sls-block-1-missions/

There is talk that EUS will not be a thing until the mid-2020s.

Europa Clipper on Block 1 is a mess, with Block 1 being able to deliver a far smaller payload to Europa than 1b, FH is in fact a lot closer to Block 1b to Europa than block 1 is (2.9t block 1 SLS, 6.5t for FH, and 8.1t for Block 2 SLS (numbers from an NSF forum post from a pretty trusted member for those sorts of figures)). It also means that EM-2 flies on a unflown upper stage. EM-2 is supposed to have a mandated fly-by date, too, and ICPS is not crew rated. Seems like man-rating the delta upper stage goes a ways towards man-rating D IV H as well...

So on the topic of DSG/LOP-G, it's either distributed launch, commercial vehicles sending all the station parts, or nothing even starts happening until the mid 2020s.

Edited by tater
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6 minutes ago, tater said:

I suggest anyone who hasn't read this NSF article do so:

https://www.nasaspaceflight.com/2018/04/nasas-dual-ml-plan-extra-sls-block-1-missions/

There is talk that EUS will not be a thing until the mid-2020s.

Europa Clipper on Block 1 is a mess, with Block 1 being able to deliver a far smaller payload to Europa than 1b, FH is in fact a lot closer to Block 1b to Europa than block 1 is (2.9t block 1 SLS, 6.5t for FH, and 8.1t for Block 2 SLS (numbers from an NSF forum post from a pretty trusted member for those sorts of figures)). It also means that EM-2 flies on a unflown upper stage. EM-2 is supposed to have a mandated fly-by date, too, and ICPS is not crew rated. Seems like man-rating the delta upper stage goes a ways towards man-rating D IV H as well...

So on the topic of DSG/LOP-G, it's either distributed launch, commercial vehicles sending all the station parts, or nothing even starts happening until the mid 2020s.

My guess is that they only start construction of LOP/G with block 1b but reduce the station a little. They already went from one habitation module to one. So they'll launch the Propulsion element on a commercial launcher, and then sometimes after 2025 launch two block 1b with one habitation and an Airlock module. After that they hopefully focus on the Lunar Return.

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1 hour ago, DerekL1963 said:

TANSTAAFL no matter how hard you keep trying to handwave one into existence.

Distributed launch is not a free lunch; it is, rather, a pretty expensive lunch.

But it is hella cheaper than the alternative, and (more importantly) it isn't nearly so subject to the whims and changing tides of Congress.

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7 minutes ago, sevenperforce said:

it isn't nearly so subject to the whims and changing tides of Congress.

Not just those external forces, but just plain SLS/Orion schedule slip.

EM-1 is going to be mid-2020 (it's slated for Dec 2019, but no one thinks that's happening).

With Block 1 as it for EM-1, SM-1 (?), EM-2, and possibly EM-3, there is not really any reason for EM-3 at all, unless they come up with a plan B involving other launch vehicles. Every year without an SLS launch is a wasted 2.whatever billion $, too. All that doesn't even acknowledge that further schedule slips are entirely possible as the problem has no schedule margin. Bad storm at Michaud again? Months delay. EUS has more problems? ICPS needs more time to be man-rated for EM-1? More SM delays for final, flight article vehicle for crew? It really is a mess.

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6 minutes ago, tater said:

Not just those external forces, but just plain SLS/Orion schedule slip.

EM-1 is going to be mid-2020 (it's slated for Dec 2019, but no one thinks that's happening).

With Block 1 as it for EM-1, SM-1 (?), EM-2, and possibly EM-3, there is not really any reason for EM-3 at all, unless they come up with a plan B involving other launch vehicles. Every year without an SLS launch is a wasted 2.whatever billion $, too. All that doesn't even acknowledge that further schedule slips are entirely possible as the problem has no schedule margin. Bad storm at Michaud again? Months delay. EUS has more problems? ICPS needs more time to be man-rated for EM-1? More SM delays for final, flight article vehicle for crew? It really is a mess.

The Shuttle was flying 4 times pretty much only testing the spacecraft itself. With EM-2 and 3 they may just fly into the NRHO orbit for rehearsal. All the while probably carrying some experiments, maybe release some cubesats into lunar orbit. 

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What is the relationship (ballpark) between the throw mass to GTO, say, vs a high lunar orbit like NRHO? 60-70% of GTO mass to a high lunar orbit? Less? More? F9 claims ~48% of GTO mass to Mars, and FH claims 62% of GTO mass to Mars. I can only assume that it's somewhere in that 60% range to NRHO. If so, Atlas and F9 can only get pretty small modules to LOP-G, like 5t. They'd also need propulsion on the parts for Falcon, as S2 doesn't have the duration to do anything once there. FH can get a full blown hab module there, it seems---again, it needs some small propulsion bus to do so. NG, OTOH, can do 13t to GTO (more with the new upper stage?), so it might well be able to deliver a hab to LOP-G alone (assuming the stage 2 has the duration to do so).

All that is without resorting to distributed launch/EOR architectures.

Such an architecture with extant LVs would be to put a real hab in LEO on some LV, then fly Atlas with nothing under the fairing but a docking port and Centaur. Dock that to the hab, and fly it to NRHO (I'd assume the Centaur would have far more props only getting itself to LEO).

Edited by tater
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8 minutes ago, tater said:

What is the relationship (ballpark) between the throw mass to GTO, say, vs a high lunar orbit like NRHO? 60-70% of GTO mass to a high lunar orbit? Less? More? F9 claims ~48% of GTO mass to Mars, and FH claims 62% of GTO mass to Mars. I can only assume that it's somewhere in that 60% range to NRHO. If so, Atlas and F9 can only get pretty small modules to LOP-G, like 5t. They'd also need propulsion on the parts for Falcon, as S2 doesn't have the duration to do anything once there. FH can get a full blown hab module there, it seems---again, it needs some small propulsion bus to do so. NG, OTOH, can do 13t to GTO (more with the new upper stage?), so it might well be able to deliver a hab to LOP-G alone (assuming the stage 2 has the duration to do so).

All that is without resorting to distributed launch/EOR architectures.

Such an architecture with extant LVs would be to put a real hab in LEO on some LV, then fly Atlas with nothing under the fairing but a docking port and Centaur. Dock that to the hab, and fly it to NRHO (I'd assume the Centaur would have far more props only getting itself to LEO).

There is little to no significant dV difference between a standard TLI and a NRHO TLI.

Falcon 9 Block 5 can send up to 6.3 tonnes on TLI and still stick the ASDS landing. It can put over 16 tonnes in LEO with ASDS landing. Falcon Heavy can send 21 tonnes to LEO or 8 tonnes to TLI, both with triple-core recovery. Expend the core and FH is throwing 22 tonnes onto TLI.

Falcon 9's upper stage goes toe-to-toe with Centaur on TLI because its mass ratio is so much better even though the RL-10 has so much more Isp than the MVac. Obviously the MVac suffers for stuff like direct injection because of duration issues.

Can Centaur get to the moon on its own? I think ACES will be needed before it can actually manage a week-long lifetime.

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1 hour ago, tater said:

So on the topic of DSG/LOP-G, it's either distributed launch, commercial vehicles sending all the station parts, or nothing even starts happening until the mid 2020s.

Considering how long it is taking to build the rocket, and the fact that only the PPM is anything more than a concept at this stage, I think you can guess which of those three options will end up happening.

 

Rune. Has any of the LOP-G components even gotten its own budget line? There's your answer.

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Politically the current state means that commercial launch is pretty much required for SLS to have something to do, then. My guess is that ULA gets thrown a bone for delivering PPE, and SpaceX gets the hab (assuming they ever line item the thing and build it). This will allow SLS to fly Orion as nothing but a crew taxi until EUS/Block 2 allows comanifested cargoes.

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1 hour ago, tater said:

ICPS is not crew rated. Seems like man-rating the delta upper stage goes a ways towards man-rating D IV H as well...

DIVH is retired for all intents and purposes. Production line has been shut down. 

It'd make more sense to just build adapters to fly Orion on New Glenn, Vulcan, and FH. 

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3 minutes ago, tater said:

Politically the current state means that commercial launch is pretty much required for SLS to have something to do, then. My guess is that ULA gets thrown a bone for delivering PPE, and SpaceX gets the hab (assuming they ever line item the thing and build it). This will allow SLS to fly Orion as nothing but a crew taxi until EUS/Block 2 allows comanifested cargoes.

Not gonna happen. How would SpaceX even get the Hab into lunar orbit?

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12 minutes ago, tater said:

Politically the current state means that commercial launch is pretty much required for SLS to have something to do, then. My guess is that ULA gets thrown a bone for delivering PPE, and SpaceX gets the hab (assuming they ever line item the thing and build it). This will allow SLS to fly Orion as nothing but a crew taxi until EUS/Block 2 allows comanifested cargoes.

Or, like you yourself have said, you could shift everything to the right, have SLS twiddle his methaporical thumbs for half a decade, while Congress funnels even more money to the usual places, in order to get the payloads designed and built. And on the other side of it, you can say you 'built the rocket so fast, its payloads weren't ready'.

 

Rune. Marks those words, I'd bet something they will be heard at some future Congress panel.

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19 minutes ago, Canopus said:

Not gonna happen. How would SpaceX even get the Hab into lunar orbit?

Hab concepts have been under 10t. FH can easily send that to nrho. The hab would require a propulsion bus to do all the maneuvers upon reaching the Moon. Such a bus will be required for anything sent ahead there without Orion, and Orion can’t send anything there til block 1b, so it’s come up with a small, disposable bus,!or dump dsg until block 1b.

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2 minutes ago, tater said:

Hab concepts have been under 10t. FH can easily send that to nrho. The hab would require a propulsion bus to do all the maneuvers upon reaching the Moon. Such a bus will be required for anything sent ahead there without Orion, and Orion can’t send anything there til block 1b, so it’s come up with a small, disposable bus,!or dump dsg until block 1b.

Yeah and there is no such bus or even any service module you could adapt to one. Other then the ESM but than it would be too heavy again. No part of LOP/G other then the PPE will fly before block 1b, because true alternatives, like ACES or maybe the new glenn tug, won‘t be around earlier.

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16 minutes ago, Canopus said:

Yeah and there is no such bus or even any service module you could adapt to one. Other then the ESM but than it would be too heavy again. No part of LOP/G other then the PPE will fly before block 1b, because true alternatives, like ACES or maybe the new glenn tug, won‘t be around earlier.

I don't disagree, I'm spitballing ways to make this thing actually fly.

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2 hours ago, tater said:

So Alabama now needs new space.

Last I recalled Atlas V and Delta IV will be flying into the 2020s. And BO is planning on building engines here afaik. 

Alabama just needs a better NASA program than SLS. MSFC hasn't developed a rocket in 40+ years... not counting SLS of course.

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14 hours ago, tater said:

Politically the current state means that commercial launch is pretty much required for SLS to have something to do, then. My guess is that ULA gets thrown a bone for delivering PPE, and SpaceX gets the hab (assuming they ever line item the thing and build it). This will allow SLS to fly Orion as nothing but a crew taxi until EUS/Block 2 allows comanifested cargoes.

Which will never happen.

14 hours ago, _Augustus_ said:

DIVH is retired for all intents and purposes. Production line has been shut down. 

It'd make more sense to just build adapters to fly Orion on New Glenn, Vulcan, and FH. 

Amusingly, it would be much cheaper to loft Orion unmanned on FH, send up crew on a Dragon 2 with F9, and then send up a Centaur, Falcon 9, or NG for the TLI burn, than to ever launch SLS.

Once BFS is flying, it eats every launch market, obviously. But in the meantime, I hope we see a distributed-launch competition between a NG-derived BLEO taxi and a Centaur/ACES BLEO taxi.

14 hours ago, tater said:

Hab concepts have been under 10t. FH can easily send that to nrho. The hab would require a propulsion bus to do all the maneuvers upon reaching the Moon. Such a bus will be required for anything sent ahead there without Orion, and Orion can’t send anything there til block 1b, so it’s come up with a small, disposable bus,!or dump dsg until block 1b.

You only need about 300 m/s to brake from TLI into NRHO. That's well within range of solid kick stages for a 5-8-tonne hab, I believe. Or you could buy a cheap hypergolic stage from the Russians. They're supposed to be partnering with this stuff, after all.

I've been building every launch that happens as it happens, over in Mission Reports, and I have not yet seen any decent US terminal delivery stages. Are there any US contractors with hypergolic upper stages for GEO insertion or other BLEO destination braking burns?

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On 4/24/2018 at 11:17 AM, sevenperforce said:

Likely the only way Vulcan can beat NG (given that they're using the same engines and ULA is paying extra) for any purpose is if they can master IVF.

KSP players take IVF for granted.

ULA can still pick up the juicy no-bid DoD and NRO launches.  I'm sure Bezos has enough political baggage that the Military Industrial Complex can still get things done the old way.  On the other hand, maybe he keep building new Amazon headquarters (or extend the competition) and make senators in finalist states steer business his way.  He's finding he has more power than just margins.

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