ZooNamedGames

[New] Space Launch System / Orion Discussion Thread

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4 minutes ago, tater said:

Because EOR is hard and LOR is easier. For reasons.

Political reasons, I guess.


Anyway, the only sensible reason that I see to go to Moon orbit first is to refuel large interplanetary ship. If you have an ISRU plant on the Moon that produces large amounts of props and a highly efficient surface-to-orbit tanker, a reusable hydrolox or NTR-powered Mars ship can park at Lunar orbit, get refilled and then depart to Mars. Eliminates the need to brake from interplanetary speed all the way to LEO and then burn to TMI again for another trip. But, obviously, it requires the Moon infrastructure first. Refilling a Starship in LEO doesn’t.

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Posted (edited)

Funnily enough for an uneeded rocket, Falcon Heavy is about to get a bunch of payloads supporting Orion SLS delivering Gateway payloads and Lunar resupply via Dragon XL.

Edited by RCgothic

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Posted (edited)
45 minutes ago, sevenperforce said:

SLS does not yet exist.

Sure it doesn't.

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Edited by Barzon

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What's the hold-up then? If it's there then why won't they just put it together and launch already?

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10 minutes ago, Barzon said:

Sure it doesn't.

When the first FH was a series of pieces being moved around to TX, then FL, etc for testing... even though the 3 cores were all the same rocket that had already flown, it didn't exist, either. Not til it flew, all up.

SLS similarly "doesn't exist." It will as soon as it flies in late 2021.

I mean if Jeff Bezos wanted to write a check to fly ~60 tons to LEO on SLS by this time next year, could he? If he wanted to write a much smaller check and send ~60 tons to LEO on FH, could he?

Whichever one the answer is "yes" to exists.

3 minutes ago, Barzon said:

They need to test it at Stennis.

Yeah, it'll be a lot closer after Green run.

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1 hour ago, tater said:

When the first FH was a series of pieces being moved around to TX, then FL, etc for testing... even though the 3 cores were all the same rocket that had already flown, it didn't exist, either. Not til it flew, all up.

SLS similarly "doesn't exist." It will as soon as it flies in late 2021.

I mean if Jeff Bezos wanted to write a check to fly ~60 tons to LEO on SLS by this time next year, could he? If he wanted to write a much smaller check and send ~60 tons to LEO on FH, could he?

Whichever one the answer is "yes" to exists.

Yeah, it'll be a lot closer after Green run.

FH required massive retooling & design modifications to support the design. Something which caused drastic delays.

SLS, by comparison does use legacy hardware (see shuttle program) and just like the shuttle program, the design needed massive retooling & redesign to support the new design. Only difference is, NASA isn't backing out at the last minute on man rating their rocket. NASA is going forward with it 100%. Especially not with the intention to turn around an make their own rocket obsolete within 5 years according to Musk with Starship.

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Posted (edited)

SLS is going to be obsolete anyway. There's a good chance Superheavy flies before SLS does. And Vulcan. And maybe New Glenn.

Edited by RCgothic

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1 hour ago, RCgothic said:

SLS is going to be obsolete anyway. There's a good chance Superheavy flies before SLS does. And Vulcan. And maybe New Glenn.

Cool, meanwhile SLS actually has a crew capsule. I'd like to see 1 photo of the starship cockpit. Much less the picture of the vehicle that'll send man to the moon (a feat I can do with SLS!)

Especially furthered by the limitations of Starship. It relies on refueling- something that's never been proven (ISS refuels are so pitifully tiny it isn't a comparison at all). Orbital refueling has never been proven to work at all. Metholox is a cyrogenic fuel which boils off over time. No system has been made to keep fuel like that from boiling off- none. Much less the ability to rendezvous with it in time before it does boil off. Current launch rates would have Starship arrive to a methane oxygen gas filled starship- but no fuel to be found. Much less a system that can pump it without freezing from the subzero temperatures. Meanwhile again- it's competition, SLS- is already built. No conceptual needs for technology that doesn't exist.

59 minutes ago, tater said:

Delays by a private company making a product they aren't even sure anyone needs doesn't matter, and is not comparable to taxpayer money, just stop.

Last I checked, NASA was SpaceX's biggest customer so my tax dollar funds their shiny steel rocket, & Falcon Heavy.

1 hour ago, tater said:

Delays by a private company making a product they aren't even sure anyone needs doesn't matter, and is not comparable to taxpayer money, just stop.

 

You are describing a few things that are actually problems.

One, the "sunk cost fallacy."

Two, man-rating SLS was a mistake in the first place. Arguably THE mistake.  Going straight to a SHLV for cargo would have made a lot of sense.

Three, if the goal was a crew vehicle, start with a clean sheet. Heck, start with a clean sheet regardless.

The legacy hardware in fact made SLS worse. Instead of picking a goal, like "We want to be able to do a lot of cool things BLEO, the min requirement would be lunar surface for at least a week, so we need (does math) 70 tons to TLI." Then you design the things to do that.

Given the legacy hardware resulting in no possible way to get more than maybe 50t to TLI, then they should have cut the sunk cost in Orion, and made a SMALLER capsule. heck, with Commercial Crew a thing, tag on a requirement that any Commercial Crew vehicle also be capable—with extra money spent by NASA—of direct entry from LLO while keeping capsule mass below 6t (whatever). Then they can design SLS knowing that by adjusting SM, etc, they can do what they need to. Instead, Orion is heavy, and can't do anything. To big/capable for LEO, not capable enough for BLEO. Orion the capsule is worth keeping, but the SM needs to be dumped, and the LV needs to change (since SLS will never be able to use a fixed Orion and do anything with it).

 

For as many problems as you claim SLS has- where's the improved alternatives? Just Starship? That's it? New Glenn is too low TLI, same for FHe. Best we have is an imploding steel tube that without it's bigger tube & refueling can't even reach SLS' destinations? Wow. Totally a bad rocket! Must be why not a single entity on planet Earth could do better!

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3 minutes ago, ZooNamedGames said:

FH required massive retooling & design modifications to support the design. Something which caused drastic delays.

Delays by a private company making a product they aren't even sure anyone needs doesn't matter, and is not comparable to taxpayer money, just stop.

 

3 minutes ago, ZooNamedGames said:

SLS, by comparison does use legacy hardware (see shuttle program) and just like the shuttle program, the design needed massive retooling & redesign to support the new design. Only difference is, NASA isn't backing out at the last minute on man rating their rocket. NASA is going forward with it 100%. Especially not with the intention to turn around an make their own rocket obsolete within 5 years according to Musk with Starship.

You are describing a few things that are actually problems.

One, the "sunk cost fallacy."

Two, man-rating SLS was a mistake in the first place. Arguably THE mistake.  Going straight to a SHLV for cargo would have made a lot of sense.

Three, if the goal was a crew vehicle, start with a clean sheet. Heck, start with a clean sheet regardless.

The legacy hardware in fact made SLS worse. Instead of picking a goal, like "We want to be able to do a lot of cool things BLEO, the min requirement would be lunar surface for at least a week, so we need (does math) 70 tons to TLI." Then you design the things to do that.

Given the legacy hardware resulting in no possible way to get more than maybe 50t to TLI, then they should have cut the sunk cost in Orion, and made a SMALLER capsule. heck, with Commercial Crew a thing, tag on a requirement that any Commercial Crew vehicle also be capable—with extra money spent by NASA—of direct entry from LLO while keeping capsule mass below 6t (whatever). Then they can design SLS knowing that by adjusting SM, etc, they can do what they need to. Instead, Orion is heavy, and can't do anything. To big/capable for LEO, not capable enough for BLEO. Orion the capsule is worth keeping, but the SM needs to be dumped, and the LV needs to change (since SLS will never be able to use a fixed Orion and do anything with it).

 

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6 minutes ago, ZooNamedGames said:

Last I checked, NASA was SpaceX's biggest customer so my tax dollar funds their shiny steel rocket, & Falcon Heavy.

Nope. It funded F9, and the 2 Dragons.

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Posted (edited)
1 hour ago, tater said:

Nope. It funded F9, and the 2 Dragons.

3.5 Dragons. NASA gives them money- they use the profit to build their vehicles. That money starts with my tax dollars.

Edited by ZooNamedGames

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7 minutes ago, ZooNamedGames said:

For as many problems as you claim SLS has- where's the improved alternatives?

SLS doesn't do anything at all. Again, what can SLS accomplish with a possible SLS cadence, by itself. We'll wait.

 

7 minutes ago, ZooNamedGames said:

Just Starship? That's it? New Glenn is too low TLI, same for FHe. Best we have is an imploding steel tube that without it's bigger tube & refueling can't even reach SLS' destinations? Wow. Totally a bad rocket! Must be why not a single entity on planet Earth could do better!

Direct TLI throw doesn't matter, any SLS-based BLEO architecture at all involves multiple launches and rendezvous by different spacecraft elements. Might as well do all of those close to home. Orion to LEO with NG. Meets with more components sent ahead to LEO. Leaves.

1 hour ago, ZooNamedGames said:

3.5 Dragons. NASA gives them money- they use the profit to build their vehicles. That money starts with my tax dollars.

They entered fixed price contracts with NASA to deliver services, which they accomplish. For crew, about half what Boeing charged NASA to not yet accomplish. Using profit to build stuff is a good thing. Overcharging then building less than what is needed... not as good.

What's your point? You honestly seem like you are intentionally straw manning SLS/Orion. Others here make far more cogent arguments in favor of the project—a project which most all of us think will continue to exist for political reasons, which is fine.

 

If I had to keep the SLS budget 100% inside Huntsville, but it could be spent as I saw fit?

I'd throw almost all of it at the NTP people, the rest to bumping TRLs for ECLSS.

NASA could buy commercial launches and spacecraft, and fly nuclear thermal propulsion testbeds. Once those demonstrate themselves, contract out spacecraft using them.

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6 minutes ago, tater said:

They entered fixed price contracts with NASA to deliver services, which they accomplish. For crew, about half what Boeing charged NASA to not yet accomplish.

I will nitpick this and point out that SpaceX has also "not yet accomplished" crew to the ISS. At least, as of right now, anyway.

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1 hour ago, tater said:

SLS doesn't do anything at all. Again, what can SLS accomplish with a possible SLS cadence, by itself. We'll wait.

 

Direct TLI throw doesn't matter, any SLS-based BLEO architecture at all involves multiple launches and rendezvous by different spacecraft elements. Might as well do all of those close to home. Orion to LEO with NG. Meets with more components sent ahead to LEO. Leaves.

For "doing nothing right" it's still the only booster capable of doing the job. Kind of strange how the NASA built rocket, can't fit your vision for Artemis architecture. I'm also going to venture a guess that your continuous commentary about SLS not being capable is from a year old comment from Berger- since SLS has been continuously improving it's payload margins with improved manufacturing processes on the part of NASA, Boeing, Rocketdyne & Lockheed.

You seem to have ignored the undeveloped challenges imposed by EOR- one of which being refueling or designing vehicles that can handle forward thrust loading. Strangely NASA saw it more practical to use existing design methods rather than trying to do something new just to chase a smaller pricetag- maybe they knew that hypothetical numbers based on designs never before tested, might not be the best starting point for a hypothesis. Again, no matter which order is used- you either waste valuable life support resources to fly crew up first, or have to design an expensive fuel tank just to keep the fuel from boiling off.

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1 minute ago, ZooNamedGames said:

For "doing nothing right" it's still the only booster capable of doing the job. Kind of strange how the NASA built rocket, can't fit your vision for Artemis architecture. I'm also going to venture a guess that your continuous commentary about SLS not being capable is from a year old comment from Berger- since SLS has been continuously improving it's payload margins with improved manufacturing processes on the part of NASA, Boeing, Rocketdyne & Lockheed.

What JOB? Again, tell us. What is the ultimate goal of the mission?

Be specific. What is the mission? Landing on the Moon? OK, how is SLS landing humans on the Moon, by itself, no help, and when?

1 minute ago, ZooNamedGames said:

You seem to have ignored the undeveloped challenges imposed by EOR- one of which being refueling or designing vehicles that can handle forward thrust loading. Strangely NASA saw it more practical to use existing design methods rather than trying to do something new just to chase a smaller pricetag- maybe they knew that hypothetical numbers based on designs never before tested, might not be the best starting point for a hypothesis. Again, no matter which order is used- you either waste valuable life support resources to fly crew up first, or have to design an expensive fuel tank just to keep the fuel from boiling off.

EOR doesn't require refilling at all. Constellation didn't.

Also, the claimed ultimate goal of Artemis is in fact propellant transfer and ISRU.

No need to design different tanks if the props are not Hydrogen. Hydrogen is always the problem, it leaks out of everything, and it has a very low boiling point. CH4 and LOX are not that bad, not even close to hydrogen.

You keep bringing up Starship. In this thread, I have never started that line of conversation here, only as replies to you, in your thread (which would be better in the Artemis thread, anyway, frankly). Since this thread includes Orion and SLS, I have brought up other LVs that could loft Orion. New Glenn, for example. NG puts 45t to LEO. That means not only could it loft Orion, it could launch Orion with a decent SM. A second launch could (really sent first) could sent that CSM to TLI. Lander having been sent ahead in parts. Note that the only change from SLS is a single EOR, the lander is still assembled with 2-3 LORs. The savings? Whatever an SLS launch costs.

Note that you can keep cargo SLS, and send the lander (assuming EUS ever exists) in 1 SLS launch. The biggest trouble with SLS is putting crew on top.

The "Steel Man" of SLS would be dumping the early blocks, and doing only Block 2 cargo. Fight me! ;)

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Posted (edited)
50 minutes ago, mikegarrison said:

I will nitpick this and point out that SpaceX has also "not yet accomplished" crew to the ISS. At least, as of right now, anyway.

They accomplished the first milestone mission both vehicles have flown. So up to the missions both have flown, 1 accomplished, 1 did not.

9 days from now with crew, but fair enough.

PS—though it was not that many months ago that Boeing got paid an additional $287,000,000 because they were ahead of SpaceX, and would have to fulfill the obligation in the CCrew contract to send 2 missions in a year, their test mission with crew actually staying on ISS longer, than an operational mission in place os SpaceX's. Which is bizarre, as that was supposed to be part of the deal from the start, and kind of the point of having 2 providers. Wonder what happened to that money?

Edited by tater

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2 hours ago, tater said:

What JOB? Again, tell us. What is the ultimate goal of the mission?

Be specific. What is the mission? Landing on the Moon? OK, how is SLS landing humans on the Moon, by itself, no help, and when?

SLS is to send crew to LOPG, whereby they will descend to the lunar surface. By comparison, Apollo's Saturn V only did the TLI kick- relying entirely on the CSM to do the work. Whereas here SLS does the work. It's mission is crew to lunar orbit- of what kind is irrelevant since from LOPG, they can access any other orbit needed using another craft. "But Zoo, if SLS can't do it then clearly it isn't a good vehicle", Comanifesting cargo is a trait NASA has no interest in repeating. They can maximize the abilities of SLS best & keep costs down by splitting launches. Which is critical for sustainability. With Apollo- there was no drawback to cancelling the program. With Artemis, especially once LOPG is launched & operational- missions can be lined up years in advance, maybe with landers that can be operational even longer (2/3 landers I am aware of, are reusable in some form or another).

2 hours ago, tater said:

Also, the claimed ultimate goal of Artemis is in fact propellant transfer and ISRU.

No, the end goal of prolonged operations on the lunar surface, such as lunar bases- this is critical in allowing us to build the experience & technologies needed to survive on Mars. Short term goals being ISRU? Maybe, but not the ultimate end goal as deep space experience is more important to us getting to Mars than utilizing on site resources- however, using those resources is a major asset but not a necessity.

2 hours ago, tater said:

You keep bringing up Starship. In this thread, I have never started that line of conversation here, only as replies to you, in your thread (which would be better in the Artemis thread, anyway, frankly).

You keep mentioning SpaceX's options, which for deep space are FHr, FHe, & Starship. We already discussed how FHr&e are poor options due to poor payload to TLI, & most definitely being unable to launch Orion to the moon (likely being at the structural limit of the vehicle). So if it isn't FH, then it must be Starship, hence why I keep mentioning it.

2 hours ago, tater said:

Since this thread includes Orion and SLS, I have brought up other LVs that could loft Orion. New Glenn, for example. NG puts 45t to LEO. That means not only could it loft Orion, it could launch Orion with a decent SM.

NASA doesn't want Orion in LEO. Hence why neither vehicles are considered. Time spent in LEO, is ECLSS wasted, not to mention adding more complexity (& with it risk), as well as requiring technology that NASA doesn't want to waste time developing when a LOR vehicle could do the same thing, but at least get man to the moon.

2 hours ago, tater said:

The "Steel Man" of SLS would be dumping the early blocks, and doing only Block 2 cargo. Fight me! ;)

Block 1 is a technology demonstrator largely. To prove the vehicle works. It's Artemis' version of Saturn 1. It puts the technology of the new program into practice, rather than theory. SLS 1B is more akin to Saturn V in functionality- being the full vehicle.

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4 minutes ago, ZooNamedGames said:

SLS is to send crew to LOPG, whereby they will descend to the lunar surface. By comparison, Apollo's Saturn V only did the TLI kick- relying entirely on the CSM to do the work. Whereas here SLS does the work.

No, SLS does not provide insertion at NRHO. Just a TLI kick. Wherever did you get that idea?? 

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1 hour ago, sevenperforce said:

No, SLS does not provide insertion at NRHO. Just a TLI kick. Wherever did you get that idea?? 

Never outright said SLS put it into any orbit. That'd be a challenge for a cyrogenic booster to keep its fuel from boiling off over the course of 3 days to get there.

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1 minute ago, ZooNamedGames said:

Never outright said SLS put it into any orbit.

You just said, "By comparison, Apollo's Saturn V only did the TLI kick- relying entirely on the CSM to do the work. Whereas here SLS does the work." What exactly is special about SLS's TLI that Saturn V's TLI lacked?

1 minute ago, ZooNamedGames said:

That'd be a challenge for a cyrogenic booster to keep its fuel from boiling off over the course of 3 days to get there.

NASA published GR&As decades on how much boiloff you get for any given prop type. It's a solved problem. On a fast transit it's miniscule for hydrolox and negligible for everything else:

LOX/LH2:   0.35% per day.
LOX/CH4:   0.20% per day.
LOX/RP1:   0.20% per day.

Just barrel-roll the SOB.

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Posted (edited)
28 minutes ago, ZooNamedGames said:

SLS is to send crew to LOPG, whereby they will descend to the lunar surface. By comparison, Apollo's Saturn V only did the TLI kick- relying entirely on the CSM to do the work. Whereas here SLS does the work.

1. SLS was a thing long before LOP-G, so no, SLS/Orion were not designed for this mission, the mission such as it is, was designed around the limitations of SSL/Orion, try again.

2. SLS does only TLI. Orion uses its anemic SM to do LOI at NRHO (or the distant orbit de jour), then the SM does TEI as well.

 

Quote

It's mission is crew to lunar orbit- of what kind is irrelevant since from LOPG, they can access any other orbit needed using another craft. "But Zoo, if SLS can't do it then clearly it isn't a good vehicle", Comanifesting cargo is a trait NASA has no interest in repeating. They can maximize the abilities of SLS best & keep costs down by splitting launches. Which is critical for sustainability. With Apollo- there was no drawback to cancelling the program. With Artemis, especially once LOPG is launched & operational- missions can be lined up years in advance, maybe with landers that can be operational even longer (2/3 landers I am aware of, are reusable in some form or another).

What? How are "costs kept down" by using SLS, well, at all?

If Gateway is there, it's just a matter of time before someone makes a better taxicab to take crew there. Literally anything smaller would do. Crew Dragon with the TPS tested for EDL from the Moon, or Starliner with improved TPS (both would require better SMs, but then again, Orion needs a better SM, too).

Quote

No, the end goal of prolonged operations on the lunar surface, such as lunar bases- this is critical in allowing us to build the experience & technologies needed to survive on Mars. Short term goals being ISRU? Maybe, but not the ultimate end goal as deep space experience is more important to us getting to Mars than utilizing on site resources- however, using those resources is a major asset but not a necessity.

None of these goals is furthered much by SLS/Orion. Like I said, if either were optimized for that role, then maybe it would be more useful.

 

Quote

You keep mentioning SpaceX's options, which for deep space are FHr, FHe, & Starship. We already discussed how FHr&e are poor options due to poor payload to TLI, & most definitely being unable to launch Orion to the moon (likely being at the structural limit of the vehicle). So if it isn't FH, then it must be Starship, hence why I keep mentioning it.

Literally the Gateway you talk about... launched by FH. Supplied by... FH.

If Starship becomes a thing, it obviates everything except Orion until another crew vehicle is demonstrated safe for direct entry from the Moon.

 

Quote

NASA doesn't want Orion in LEO. Hence why neither vehicles are considered. Time spent in LEO, is ECLSS wasted, not to mention adding more complexity (& with it risk), as well as requiring technology that NASA doesn't want to waste time developing when a LOR vehicle could do the same thing, but at least get man to the moon.

Orion was in fact designed for LEO, hence the lousy SM. Orion is the Constellation MPCV, which was supposed to ALSO be NASA's crew vehicle to ISS as you should probably recall.

This is the problem, too many legacy parts. Make a clean sheet LV, but require it use parts "just because" (really to line the pockets of the right people), instead of making an optimal design. Then, require that it use a NOT clean sheet crew vehicle, one that was designed with a specific mission profile in mind—EOR with large element that do the heavy lifting at the Moon (Altair was to do LOI in LLO, allowing Orion to work from LLO).

Quote

Block 1 is a technology demonstrator largely. To prove the vehicle works. It's Artemis' version of Saturn 1. It puts the technology of the new program into practice, rather than theory. SLS 1B is more akin to Saturn V in functionality- being the full vehicle.

B1 was only ever supposed to fly ONCE. As such, it was a real waste. EUS should already be a thing, but it isn't. Even WITH the EUS, SLS lacks the ability to send useful payloads to accomplish lunar missions—because Orion was never designed with this in mind.

The best SLS/Orion strategy would be to realize that Orion is hobbled to Constellation architecture, and move accordingly. Jump directly to SLS Block 2, no need to crew rate it. Make it as cheap as possible (unlikely to help). Since NG is set to fly soon, and can easily loft Orion, throw some money at BO for speeding that up.

16 minutes ago, ZooNamedGames said:

Never outright said SLS put it into any orbit. That'd be a challenge for a cyrogenic booster to keep its fuel from boiling off over the course of 3 days to get there.

Both ICPS and EUS as currently planned burn to put Orion/cargo in a parking orbit, then do a burn to TLI, and is discarded. There is no current plan to have EUS do anything else.

If they dumped Boeing, and used ULA, then they could have an ACES EUS, and then they could possibly fill the tank, and have EUS do LOI. Comanifested cargo mass would suffer.

6 minutes ago, sevenperforce said:

NASA published GR&As decades on how much boiloff you get for any given prop type. It's a solved problem. On a fast transit it's miniscule for hydrolox and negligible for everything else:

LOX/LH2:   0.35% per day.
LOX/CH4:   0.20% per day.
LOX/RP1:   0.20% per day.

Just barrel-roll the SOB.

Exactly, boiloff is a real issue for long term storage, and for long missions like Mars (0.35%*several hundred days is a problem ;) ). It's meaningful in cislunar largely for prepositions assets. So if launch phasing requires something sent a month ahead of time or more, prop losses might become meaningful, short of that? meh.

Edited by tater

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1 hour ago, sevenperforce said:

You just said, "By comparison, Apollo's Saturn V only did the TLI kick- relying entirely on the CSM to do the work. Whereas here SLS does the work." What exactly is special about SLS's TLI that Saturn V's TLI lacked?

NASA published GR&As decades on how much boiloff you get for any given prop type. It's a solved problem. On a fast transit it's miniscule for hydrolox and negligible for everything else:

LOX/LH2:   0.35% per day.
LOX/CH4:   0.20% per day.
LOX/RP1:   0.20% per day.

Just barrel-roll the SOB.

It can still take multiple days, maybe even weeks to get a launch underway, so those loses are considerable.

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1 hour ago, tater said:

1. SLS was a thing long before LOP-G, so no, SLS/Orion were not designed for this mission, the mission such as it is, was designed around the limitations of SSL/Orion, try again.

And the vehicle was still in development. LOPG was first envisioned as the Deep Space Habitat in 2012- a year after SLS was signed into development. SLS was largely a LV built to ferry Orion & maybe cargo. It's destination was always deep space. Even before Artemis, EM-1 was to do a lunar flyby- this was back in 2012 as well. By comparison- Saturn V also lacked much in the end goal. In fact LOR was only selected 5 years before Saturn V first flew. Prior to that- the entire structure of Apollo was also- in limbo. Which is why the CSM's engine is so powerful- it was initially designed to land on the moon from the EOR era.

1 hour ago, tater said:

If Gateway is there, it's just a matter of time before someone makes a better taxicab to take crew there. Literally anything smaller would do. Crew Dragon with the TPS tested for EDL from the Moon, or Starliner (both would require better SMs, but then again, Orion needs a better SM, too).

Well NASA's been waiting since the 2000s when they started to refocus on the moon. It's been 20 years, NASA is tired of waiting. SLS flies crew within 3 years (Artemis 1 may be delayed by Artemis 2 is almost entirely unaffected by A1 delays).

1 hour ago, tater said:

Literally the gateway you talk about... launched by FH. Supplied by... FH.

I see nothing saying a launcher has been finally selected. Considered? Yes. Selected? No.

1 hour ago, tater said:

If Starship becomes a thing, it obviates everything except Orion until another crew vehicle is demonstrated safe for direct entry from the Moon.

Yeah that bellyflop landing, lack of parachutes, still unreliable landing technology, lack of abort modes, unproven heatshield (not to mention it'll need reworking for lunar re-entry heating), lack of radiation shelter... the vehicle has many many many many many challenges to prove itself. It's taken SpaceX a decade to meet NASA's standards with a standard capsule. much less a radical new design that relies on exploding technology.

1 hour ago, tater said:

Orion was in fact designed for LEO, hence the lousy SM. Orion is the Constellation MPCV, which was supposed to ALSO be NASA's crew vehicle to ISS as you should probably recall.

That was also a decade ago, more than by this point. Changes have occurred. That may have been it's design in 2008, but in 2020 that is not the case.

orionz.jpg?ve=1&tl=1

vs

orion-complete-2.jpeg

1 hour ago, tater said:

This is the problem, too many legacy parts. Make a clean sheet LV, but require it use parts "just because" (really to line the pockets of the right people), instead of making an optimal design. Then, require that it use a NOT clean sheet crew vehicle, one that was designed with a specific mission profile in mind—EOR with large element that do the heavy lifting at the Moon (Altair was to do LOI in LLO, allowing Orion to work from LLO).

1) Legacy eases development. Work with the F-1 shows how problematic new hardware can be. Meanwhile boosters are already ready, engines, optimized, improved, & ready. So many elements are already finished, in advance of what any other program could achieve.

2) For a "pork" program, it's kind of crappy when Apollo had 2x the number of contractors.

1 hour ago, tater said:

The best SLS/Orion strategy would be to realize that Orion is hobbled to Constellation architecture, and move accordingly. Jump directly to SLS Block 2, no need to crew rate it. Make it as cheap as possible (unlikely to help). Since NG is set to fly soon, and can easily loft Orion, throw some money at BO for speeding that up.

Except it can't send it to the moon, which is NASA's destination.

I know you have a fascination for LEO- but NASA's been there for 30 years- they're kind of bored of it!

Even if it could send to LEO- great. Now there's no tug to send it anywhere. So that's more time and more tax dollars to build a new vehicle when SLS would be ready & waiting.

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1 hour ago, tater said:

Crew Dragon with the TPS tested for EDL from the Moon, or Starliner (both would require better SMs, but then again, Orion needs a better SM, too).

Somehow I missed this-

But Dragon 2 doesn't have the radiation shielding to make the trip, doesn't have the ECLSS to (7 undocked days, just barely enough to make it to the moon at all), SM is insufficient to do any lunar operations, spacecraft frame isn't built for lunar re-entry, it's too tiny (I couldn't imagine living in what's the size of a SUV for 3 days with a crew of 3-4 others). Same applies to Starliner. By the time you modify those vehicles, they would exceed their launch vehicles abilities & necessitate a larger vehicle.

Orion, is the only one that passes all of those requirements.

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