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NASA SLS/Orion/Payloads

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If this is anything like the one on the cors SLS stage, it'll leave a mark.

 

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Between the audit and looking at commercial alternatives, one might almost think NASA was trying to light a fire under the ULA when it comes to SLS.

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I put the chances of Orion on a commercial vehicle very near zero.

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On 3/14/2019 at 1:18 PM, DDE said:

That’s not how NASA rolls. They ordered the SLS, not an SLS-class booster.

Otherwise Energiya (the company) would have responded to their RFPs, even if in jest.

OK, than why couldn't they cancel current-state SLS developement and make a sort of commercial competition (i guess that's what they done back in 00-s, but i mean again with Elon and Jeff and all that stuff), than say "use that parts if possible pls" (if that's really THAT matter) and give all that billions to someone way more effective than current SLS developers? I mean Elon claims that Starship needs only $5 billion to R&D and it's already partly done - with $20 billion of SLS money NASA could get 4 Starship-class projects finished!

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29 minutes ago, NiL said:

than say "use that parts if possible pls" (if that's really THAT matter)

They know really well that “if possible” is going to stop absolutely no-one, unless they actually introduce a system favouring off-the-shelf... at which point SLS will win over any and all competition.

Remember Apollo, the one built by North American?

1538426_original.jpg

It wasn’t the winner of the final RFP by formal criteria. This was:

martin-410-cutaway-diagram.jpg

This Martin 410 design was supposed to become Apollo, but Maxime Faget said “no” and so NASA found an excuse to reject it entirely in favour of something Faget essentially designed himself 

You will never be able to force a space agency to ditch an in-house design, or an effectively in-house design by a hand-picked supplier, for a commercial one.

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https://twitter.com/NASA

Bridenstine and Pence are currently doing an announcement/talk thing and one of the key points is that they aim to return humans to the lunar surface within 5 years, and another that they are aiming for the first SLS flight in 2020.

I can't really watch it right now so I'm not sure about the details, but I'm curious as to how they could accomplish a lunar landing in 2024 with SLS. Assuming optimistically a 2020 EM-1 (unmanned), a 2022 EM-2 (manned flyby or orbit), a 2023 lander, a commercially launched transfer vehicle, and a 2024 EM-3 Orion to transfer the crew to the transfer vehicle in elliptical orbit, to the lander in low orbit, and then carry out the mission from there, then it might be possible, but that would require a flight rate far greater than anticipated, development of a lander from pretty much scratch in 4 years, and not paying attention to Gateway until at least 2025.

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Yeah, a 2024 landing requires that EM-3 meet up with a lander waiting for it, already tested. This seems stunningly optimistic barring large amounts of money being thrown at commercial contractors.

That or they're secretly counting on just buying a flight with crew, lol.

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5 minutes ago, tater said:

Yeah, a 2024 landing requires that EM-3 meet up with a lander waiting for it, already tested. This seems stunningly optimistic barring large amounts of money being thrown at commercial contractors.

That or they're secretly counting on just buying a flight with crew, lol.

To be fair, Apollo had 2 unmanned Saturn test flights, crew on Apollo 8, a lander test in LLO on Apollo 10, and a landing on Apollo 11, requiring 5 Saturn V rockets for a landing. If we say that technological advancements and heritage tech eliminate the need for one of the 2 test flights, we have 4 SLS flights necessary. The Low Lunar Orbit test can also be taken out if necessary, replaced by extensive ground testing and trusting advancements in technology, along with a LEO test on a commercial Vehicle, like Apollo 5, which used a Saturn IB.

This brings us down to 3 Exploration Missions, plus the lander launch mission. Theoretically, though, the lander could also launch on two commercial vehicles, one for the payload and one for a kick stage, but that would bring up the commercially launched Orion argument again, which invalidates SLS, so that may not happen. 4 SLS launches might be on the brink of possibility before 2024, but I wouldn't bet on it sticking.

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I'd assume that commercial vehicles would be required to send lander, and the tug to get said lander from Gateway to LLO and back. Presumably they'd do a full lander test robotically (that's far more doable now than during Apollo, as the lander will land itself, anyway).

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Less SLS, more general NASA, but...

All of the Mars surface missions we've launched used direct entry from a hyperbolic trajectory. However, a sample mission would need to carry a heat shield for Earth return. How punishing is re-entry from low Martian orbit alone, rather than hyperbolic entry? Using the Earth-return heat shield to aerobrake the entire stack into LMO before separating the lander (leaving the Earth return props and heat shield in orbit for a Martian orbit rendezvous) could allow for a much smaller EDL heat shield and a very small (perhaps solid-fueled) MAV.

Feasible?

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Does anyone have a source for how quickly water can be split into H and O? I was thinking about prop depots, and the fact that water is far more storable. The critical math is can you split it (with solar power) substantially faster than the components boil off (assuming that boiloff is minimized at the depot).

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Not sure. The bottleneck is probably going to be refrigeration of the propellants. Once you have that capability, though, boiloff becomes a moot point.

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34 minutes ago, tater said:

Does anyone have a source for how quickly water can be split into H and O? I was thinking about prop depots, and the fact that water is far more storable. The critical math is can you split it (with solar power) substantially faster than the components boil off (assuming that boiloff is minimized at the depot).

Water electrolysis cannot be done at cryogenic temperatures, so you will need to use a rather large radiator array in order to cool GOX and H2 gas into liquids. Since you need radiators anyway, just use them to control boiloff. Voila.

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14 minutes ago, sevenperforce said:

Water electrolysis cannot be done at cryogenic temperatures, so you will need to use a rather large radiator array in order to cool GOX and H2 gas into liquids. Since you need radiators anyway, just use them to control boiloff. Voila.

Yeah, that's what I thought, but once stored, there is still non-zero boiloff, even with active cooling, right? I was under the impression that it was still something being worked on, but nothing like off the shelf yet. If they had minimal boiloff (using any current capability) tanks that lost some fraction of a %/day, and the tanks could only be filled from cracked water at a similar rate, they'd never be filled. Assuming you can crack, then chill substantially faster, it seems like the optimal solution for transport of props to Gateway would be maximal water loads, with a prop depot that can split the props as needed. This is particularly true given the extremely low flight cadence to Gateway possible with Orion.

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40 minutes ago, tater said:

Yeah, that's what I thought, but once stored, there is still non-zero boiloff, even with active cooling, right? I was under the impression that it was still something being worked on, but nothing like off the shelf yet. If they had minimal boiloff (using any current capability) tanks that lost some fraction of a %/day, and the tanks could only be filled from cracked water at a similar rate, they'd never be filled. Assuming you can crack, then chill substantially faster, it seems like the optimal solution for transport of props to Gateway would be maximal water loads, with a prop depot that can split the props as needed. This is particularly true given the extremely low flight cadence to Gateway possible with Orion.

No, the goal would be ZBO. Your condenser is going to take gas from a reservoir, cool it with a heat exchanger and radiators, and then dump it into the prop tank. Boiloff from the prop tank would simply be vented back into the gas reservoir. 

This reference study specifies that while Qref/QHL (refrigeration power divided by heat leak) may be less than 1 for certain expendable propellant depots or prop delivery systems, any system capable of cracking H2O into props would necessarily need to have Qref/QHL > 1.

The bottleneck would be how long it takes to condense the gaseous props. If that process is too slow, then you need more radiators. But boiloff per se is just venting back into the electrolysis chamber; nothing is lost.

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On 3/26/2019 at 9:31 AM, NiL said:

OK, than why couldn't they cancel current-state SLS developement and make a sort of commercial competition (i guess that's what they done back in 00-s, but i mean again with Elon and Jeff and all that stuff), than say "use that parts if possible pls" (if that's really THAT matter) and give all that billions to someone way more effective than current SLS developers? I mean Elon claims that Starship needs only $5 billion to R&D and it's already partly done - with $20 billion of SLS money NASA could get 4 Starship-class projects finished!

As I've always stated, SLS is a program that guarantees man rated heavy lift capability. Commercial has always been welcome to try and create their own heavy lift vehicles but NASA hasn't mandated it due to NASA needing SpaceX, ULA and BO in low Earth orbit more than they need them in lunar orbit. NASA is guaranteed funding by congress, and as a result isn't affected by economic strains. Corporate companies like SpaceX, ULA, and BO are affected and as a result, can end up cancelling their heavy lift programs to save money.

Once these super heavy lift vehicles (BFR, New Glenn, Vulcan, etc) are actually flying and proven safe and reliable by NASA, I have no doubt SLS will be on the cutting block. But until then, SLS is all NASA will consider as NASA won't wait for another company to make a promise they may have to bail on, and thus, end up with no super heavy lift vehicles at all.

Not to mention, like the Space Shuttle, NASA's experience with developing and engineering new vehicles is shared with the industry as a whole and paves the way for other SHLV to build on NASA's experience with the SLS.

Just my thoughts once again

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1 hour ago, ZooNamedGames said:

As I've always stated, SLS is a program that guarantees man rated heavy lift capability.

This is in fact the major problem with SLS. It guarantees people on top of an HLV capable of going... nowhere.

Constellation rightly separated heavy lift from crew.

Once again, it's a matter of setting specific goals, then pursuing them. If the goal is an Apollo style single stack to the Moon and back, then you need a HLV with crew on top, since you need at least 140 tonnes in LEO. If your crew vehicle is Orion, then you need substantially more than that, or the LV is useless. SLS will never lift the required mass to LEO for an Apollo-style mission, so an Apollo mission cannot possibly be a goal for SLS.

The point of a generic HLV capability is a fine goal. That would be Block 2. They should have skipped the other versions, and never bothered crew rating SLS (ie: they should have stuck with Ares V). A crew rated SLS is in fact USELESS.

It is too expensive and large to fly more than once a year. The crew vehicle could in fact be launched on extant rockets for vastly less than the 3+ billion each SLS launch will cost. Dock to ISS, then send up an upper stage with a docking ring, and use that as a tug to send Orion where you want it to go. Still cheaper than SLS. That or launch Orion, and immediately follow at next available pass with a DIV (ICPS is a DIV upper stage).

If the goal is sending people to distant lunar orbits (for reasons), then the question is can it be done cheaper with a different LV? Also, is the cargo version (the only version that can ever even be possibly useful) a better use of the single launch per year they will ever have?

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Just now, tater said:

This is in fact the major problem with SLS. It guarantees people on top of an HLV capable of going... nowhere.

Lunar orbit. Just because we don't like LOP-G and many have stated it's pointless doesn't mean SLS has no destination. Even the Saturn V, prior to Apollo 11, had a destination.

2 minutes ago, tater said:

Once again, it's a matter of setting specific goals, then pursuing them. If the goal is an Apollo style single stack to the Moon and back, then you need a HLV with crew on top, since you need at least 140 tonnes in LEO. If your crew vehicle is Orion, then you need substantially more than that, or the LV is useless. SLS will never lift the required mass to LEO for an Apollo-style mission, so an Apollo mission cannot possibly be a goal for SLS.

Unless NASA doesn't intend to do a Saturn V LOR launch. There's option for EOR and LOR with LOP-G. It's completely feasible that they could launch a crew to LOP-G which would board a lander which was deployed months prior, and then make their descent to the surface and back to LOP-G. Meaning SLS doesn't need to launch Orion and a lander, merely one or the other.

4 minutes ago, tater said:

The point of a generic HLV capability is a fine goal. That would be Block 2. They should have skipped the other versions, and never bothered crew rating SLS (ie: they should have stuck with Ares V). A crew rated SLS is in fact USELESS.

In that case NASA should've never man rated the Saturn V.

I know I just said comparing the SLS to the Saturn V is a poor comparison but when it comes to "destinationless" heavy lifters, they do share similar functions. Not to mention NASA already HAS several non-man-rated rockets already. Atlas V 551, Falcon Heavy, Delta IV Heavy, and so on. So for all the "they don't need SLS", you seem to ignore the fact that they already have what you're saying SLS should be. Clearly they want a SHLV that is man rated. So they pursue SLS' development.

9 minutes ago, tater said:

It is too expensive and large to fly more than once a year. The crew vehicle could in fact be launched on extant rockets for vastly less than the 3+ billion each SLS launch will cost. Dock to ISS, then send up an upper stage with a docking ring, and use that as a tug to send Orion where you want it to go. Still cheaper than SLS. That or launch Orion, and immediately follow at next available pass with a DIV (ICPS is a DIV upper stage).

Which relies on vehicles and concepts we've yet to prove. Launching crew on top of a giant rocket and assembling a space station are things that we have already proven we are capable of. Besides, we don't want to go much further than the moon right now and I wholly agree with that proposal as we have very little experience in and around the moon (878 days on the ISS vs ~12.5 days during Apollo 17 during their trip onto, and from the moon). Honing our skills there would prove infinitely more valuable than throwing ourselves at such a massive hurdle like Mars or any other destination beyond Earth's SOI.

Do we need SLS launching more than a few times a year? Beyond crew launches, we don't really have a need. Even with LOP-G needing routine cargo resupplies, those resupply missions can be done with other vehicles. Even the Soyuz is only launched 4 times a year to the ISS. In 2010 there were only 3 shuttle missions to the ISS. With the whole intent being for extended crew duration on the space station we don't need to launch multiple crewed SLS missions a year. The expectation of how many times it should fly is a fallacy as you're basing it on other vehicles and what it should do, not what it needs to do.

21 minutes ago, tater said:

If the goal is sending people to distant lunar orbits (for reasons), then the question is can it be done cheaper with a different LV? Also, is the cargo version (the only version that can ever even be possibly useful) a better use of the single launch per year they will ever have?

Potentially, but that again refers to what is decided what needs to be done for that year.

As to lunar orbit, yes, plenty of vehicles can fly spacecraft there. Only issue none of those vehicles are man rated. SLS will be.

 

 

Also I'd like to highlight my earlier comment which went unanswered-

2 hours ago, ZooNamedGames said:

Not to mention, like the Space Shuttle, NASA's experience with developing and engineering new vehicles is shared with the industry as a whole and paves the way for other SHLV to build on NASA's experience with the SLS.

 

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2 minutes ago, ZooNamedGames said:

Lunar orbit. Just because we don't like LOP-G and many have stated it's pointless doesn't mean SLS has no destination. Even the Saturn V, prior to Apollo 11, had a destination.

This goal was set AFTER SLS was developed, not before.

Constellation had the goal of cislunar, and Mars. The HLV could put 188 tonnes in LEO, never having to also lift Orion.

SLS only had the goal of employing Shuttle workers.

4 minutes ago, ZooNamedGames said:

In that case NASA should've never man rated the Saturn V.

I know I just said comparing the SLS to the Saturn V is a poor comparison but when it comes to "destinationless" heavy lifters, they do share similar functions. Not to mention NASA already HAS several non-man-rated rockets already. Atlas V 551, Falcon Heavy, Delta IV Heavy, and so on. So for all the "they don't need SLS", you seem to ignore the fact that they already have what you're saying SLS should be. Clearly they want a SHLV that is man rated. So they pursue SLS' development.

Wrong.

Apollo was perfect for the goal, sortie missions to the Moon from Earth. Rendezvous was still barely tested, and non-trivial. It's literally automated now.

Goals come FIRST, vehicles are designed to achieve a goal. SLS has no goal, except goals added after the fact.

6 minutes ago, ZooNamedGames said:

Do we need SLS launching more than a few times a year? Beyond crew launches, we don't really have a need. Even with LOP-G needing routine cargo resupplies, those resupply missions can be done with other vehicles. Even the Soyuz is only launched 4 times a year to the ISS. In 2010 there were only 3 shuttle missions to the ISS. With the whole intent being for extended crew duration on the space station we don't need to launch multiple crewed SLS missions a year. The expectation of how many times it should fly is a fallacy as you're basing it on other vehicles and what it should do, not what it needs to do.

You realize that LOP-G will only be occupied for about 1 week a year, right?

One flight of SLS, limited to a few weeks total duration. A few days each way to Gateway. The rest at Gateway. There are no routine resupply missions required as the Gateway missions don't ever exceed what Orion can carry aboard, anyway.

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Just now, tater said:

This goal was set AFTER SLS was developed, not before.

SLS dates back to the 90s with the National Launch System so that's a fallacious argument. Goal was vague because the vehicle was always conceptualized in the future tense. SLS is present tense and its present goal is lunar flight. Pretty straight forward.

2 minutes ago, tater said:

SLS only had the goal of employing Shuttle workers.

And Musk isn't just keeping his engineers busy by proposing some new vehicle or giving one of his new pet projects new goal, or changing them entirely. Surprise! No one is efficient at developing new vehicles that have never been built or operated before and any expectations or assumptions are entirely based on personal ideals and plans based on prior experience.

 

Seeing as SLS doesn't need to be efficient, and that NASA doesn't need to worry about their profit margins, their bottom line or appeasing their stockholders, they can focus on just building a rocket; it isn't efficient; it isn't cheap; it isn't perfect, but it's chosen to complete the tasks set for it.

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Posted (edited)

Gateway only exists as a mission to give SLS something to do. It was never the goal to which SLS was built. SLS is not capable of doing anything actually useful, so they came up with Gateway. Originally SLS/Orion was to build Gateway. That's not a thing any more. Block 1 SLS was only every supposed to launch EM-1 to test the all-up Orion, because that block was never more than a boilerplate launcher.

36 minutes ago, ZooNamedGames said:

SLS dates back to the 90s with the National Launch System so that's a fallacious argument. Goal was vague because the vehicle was always conceptualized in the future tense. SLS is present tense and its present goal is lunar flight. Pretty straight forward.

I was specifically praising Constellation as a counterpoint to the similar, but crippled SLS program. Constellation is what NLS became. It had an open set of goals (cislunar and MArs for crew missions), and Ares V was capable of serving that goal. SLS Block 2 cannot even manage cislunar utility.

It wanted a HLV capable of supporting both cislunar, and potential Mars operations. SLS is capable of neither.

It also was to leverage Shuttle tech, then operational. So far that means spending 3X the new cost of each SSME used in SLS. We already bought them for ~40M$ eeach, and now AJR is reselling them to use for an additional 127 M$ each. Which saves money, somehow?

 

Quote

And Musk isn't just keeping his engineers busy by proposing some new vehicle or giving one of his new pet projects new goal, or changing them entirely. Surprise! No one is efficient at developing new vehicles that have never been built or operated before and any expectations or assumptions are entirely based on personal ideals and plans based on prior experience.

Why are you bringing up SpaceX, exactly? This is about the dumpster fire that is SLS. Boeing has mismanaged the program (as NASA's own review has shown). NASA is rightfully annoyed at this point.

Since you brought it up, Musk has one goal---I should add that I don't agree with that goal---the permanent habitation of Mars. That goal has not changed even once. Goal has not shifted at all. The vehicle rightly has, as they determine what will do what they need it to do. Too bad SLS is not so agile. SLS is the very definition of the sunk cost fallacy. They've started, and there is no way to turn it into something actually useful without a major revision, so they plod on. Swapping Block 2 for Ares V might be a start, as the throw mass of Ares V actually facilitates a wide range of possible missions. Separating crew from HLV means that being stuck with 1 launch a year doesn't matter, since the crew doesn't count as that launch. Block 1b cannot ever launch crew and any surface sortie vehicle in one go. You either need 1 stack, or you don't. Since SLS/Orion cannot do anything useful in 1 launch, distributed launch is therefore required---far more sensible to make SLS be the HLV for cargo, and move crew (Orion) to another launch vehicle.

There are multiple to choose from now, or in the near future (roughly ordered from existing to time possibly available):

ULA Delta IV Heavy.

SpaceX Falcon Heavy.

ULA Atlas HLV (looks like D IVH, but with atlas V), long proposed unsure if faster dev than the next 2).

ULA Vulcan (metal bending as we speak)

Blue Origin New Glenn.

 

Quote

Seeing as SLS doesn't need to be efficient, and that NASA doesn't need to worry about their profit margins, their bottom line or appeasing their stockholders, they can focus on just building a rocket; it isn't efficient; it isn't cheap; it isn't perfect, but it's chosen to complete the tasks set for it.

No, it's not chosen to complete any task, that's the problem (unless you define the task as employing people in the right districts).

What is the task of SLS that existed before it was designed? Be specific.

Edited by tater

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Posted (edited)
58 minutes ago, tater said:

Gateway only exists as a mission to give SLS something to do. It was never the goal to which SLS was built. SLS is not capable of doing anything actually useful, so they came up with Gateway. Originally SLS/Orion was to build Gateway. That's not a thing any more. Block 1 SLS was only every supposed to launch EM-1 to test the all-up Orion, because that block was never more than a boilerplate launcher.

Ironically I remember someone complaining that SLS was being built only for Gateway. Now people are complaining it's being built for "no real purpose". Like seriously, which side are you on. Is building SLS for something good or bad.

58 minutes ago, tater said:

I was specifically praising Constellation as a counterpoint to the similar, but crippled SLS program. Constellation is what NLS became. It had an open goal, and Ares V was capable of serving that goal.

Yes, both were open goals as they were paper rockets. Now SLS is not, so an open goal is no longer sufficient. A concrete plan is required.

58 minutes ago, tater said:

So far that means spending 3X the new cost of each SSME used in SLS. We already bought them for ~40M$ eeach, and now AJR is reselling them to use for an additional 127 M$ each. Which saves money, somehow?

Again, NASA is a government program. They can spend this kind of money and not worry about their bottom line, profit margins, and appeasing stock holders (as I literally said word for word in an earlier comment). NASA is letting corporate entities worry about cost. NASA's getting the money whether they spend 100x the cost or 1/100th the cost. Lower cost could mean more launches buy as I said earlier, I haven't seen a need to launch SLS so frequently.

58 minutes ago, tater said:

Why are you bringing up SpaceX, exactly? This is about the dumpster fire that is SLS.

 

I mention it as SpaceX is the only corporate entity promising the moon right now. Literally. With SpaceX's dumpster fire of ITS... I mean BFR... I mean Super Heavy... I mean Starship... I mean [Insert random new radical name Musk has chosen for his overhaul of the program].

58 minutes ago, tater said:

Since you brought it up, Musk has one goal---I should add that I don't agree with that goal---the permanent habitation of Mars. That goal has not changed even once. Goal has not shifted at all. The vehicle rightly has, as they determine what will do what they need it to do.

And Musk has proven, like NASA, he comes up unable to meet his promises and almost always late. Falcon Heavy launch 2013? Try 5 years after the fact. Man rated Falcon Heavy? Not going to happen. Propulsive landing of the Dragon 2? Not going to happen. Dragon 2 to Mars? Not going to happen. Musk does change his plans, and his intentions. Yes, his long term goal of Mars hasn't shifted, but to be fair, Mars is still NASA's long term goal; so you can't say NASA has been changing their goal while ignoring the fact that like NASA, SpaceX is shifting towards the moon as well with Mars firmly in the future.

58 minutes ago, tater said:

There are multiple to choose from now, or in the near future (roughly ordered from existing to time possibly available):

ULA Delta IV Heavy.

SpaceX Falcon Heavy.

ULA Atlas HLV (looks like D IVH, but with atlas V), long proposed unsure if faster dev than the next 2).

ULA Vulcan (metal bending as we speak)

Blue Origin New Glenn.

ULA Delta IV Heavy. - Not Man Rated- Never will be

SpaceX Falcon Heavy. - Not Man Rated- Never will be

ULA Atlas HLV (looks like D IVH, but with atlas V), long proposed unsure if faster dev than the next 2). - Discontinued, no longer offered

ULA Vulcan (metal bending as we speak) - Distant future; unproven

Blue Origin New Glenn. - Distant future; unproven

58 minutes ago, tater said:

No, it's not chosen to complete any task, that's the problem (unless you define the task as employing people in the right districts).

What is the task of SLS that existed before it was designed? Be specific.

Heavy lift. It's a rocket. Not a spacecraft. It throws it's cargo to a specific destination. It's function was always between the moon and Mars. Whether ARM, Lunar operations, or Mars missions. Alterations to the design (like BFR's development, shocking I know) has proven that it's not capable of all the promises made before the numbers were crunched (almost like BFR). So expectations were simplified. This isn't even unlike the Saturn V which was expected to launch a wide verity of things prior to it's completed assembly, and like SLS, it also had a wide range of uses as it was only a booster. It could've been utilized in preparing and assembling Mars missions, launching lunar space stations, launching lunar cargo, and that's just the tip of the iceberg. Oh, and the Saturn V was extremely inefficient and post Apollo 11, was only in operation to keep those jobs open. Since they had cheaper rockets that could launch heavy payloads (Titan IIIC, Titan IIIE+Centaur, Titan 34D, Delta III 3940) and all of which could've launched lunar cargo or lunar modules for far cheaper than the extremely cost ineffective, Saturn V.

Edited by ZooNamedGames

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Posted (edited)
57 minutes ago, ZooNamedGames said:

Ironically I remember someone complaining that SLS was being built only for Gateway. Now people are complaining it's being built for "no real purpose". Like seriously, which side are you on. Is building SLS for something good or bad.

Two things can be true at once. SLS is now being built supposedly because of Gateway. Before that it was for ARM (a mission that never required crew at all, frankly, it was make-work as well).

SLS is for nothing at all. Nothing is neither good, nor bad, it's nothing.

Quote

Yes, both were open goals as they were paper rockets. Now SLS is not, so an open goal is no longer sufficient. A concrete plan is required.

A concrete plan should have come first, or the open nature should have resulted in a vehicle so broad in capability, most reasonable goals could be achieved. What's the min mass to LEO to do whatever it is the goal might include?

188 tonnes to LEO (Ares V) achieves the latter. You can put a stack in LEO than Orion can dock to, and it can go to anywhere in cislunar (including the surface), and the Mars DRA used vehicles lifted by a few Ares V launches to imagine human Mars missions. SLS cannot do either. Ever. Block 2 cannot get enough to LEO to doc in LEO with Orion and go to the Moon since it cannot fly twice in a few weeks. You either fly crew, or you fly cargo, and any cargo with propellant will not wait for a year for the crew.

 

Quote

Again, NASA is a government program. They can spend this kind of money and not worry about their bottom line, profit margins, and appeasing stock holders (as I literally said word for word in an earlier comment). NASA is letting corporate entities worry about cost. NASA's getting the money whether they spend 100x the cost or 1/100th the cost. Lower cost could mean more launches buy as I said earlier, I haven't seen a need to launch SLS so frequently.

They need to if the goal is to complete a mission that requires multiple SLS launches, because SLS was poorly designed. The current talk is crew landings on the Moon. Orion requires an SLS launch. Any lander is in fact more massive than Orion, and must also get to the Moon, and do a LOI burn into the bargain. If SLS can't get Orion there, it cannot get a larger lander there, either. Stacking crew on the HLV was entirely to avoid distributed launch, now their goal literally requires, what, 1 SLS, and at least 3 commercial HLV launches to accomplish (and that's after Gateway is built---by commercial vehciles)? More?

 

Quote

I mention it as SpaceX is the only corporate entity promising the moon right now. Literally. With SpaceX's dumpster fire of ITS... I mean BFR... I mean Super Heavy... I mean Starship... I mean [Insert random new radical name Musk has chosen for his overhaul of the program].

Dumpster fire? Raptor exists. Flight article engine fired at flight article power. Vulcan/NG have an engine now up to 80% power in testing.

Hopper test vehicle sitting on the pad, with an engine in it, right now, in testing. Orbital altitude test vehicle under construction (you can see pictures). How is this a dumpster fire, exactly? They are actually building hardware. Changing the design as required is called being intelligent. Continuing with a design after you realize another way is better is foolish. Von Braun was rightly converted to LOR vs his preferred EOR architecture. Agility is good.

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And Musk has proven, like NASA, he comes up unable to meet his promises and almost always late. Falcon Heavy launch 2013? Try 5 years after the fact.

This reads like someone not paying attention. FH was built with no one's money except his own, who cares about timeline? It was also proposed at a time when it was literally required to lift payloads that F9 could not lift, then F9 Block 3 could lift them, expendable, so there was little reason to need it. As it is, it now exists only to fly payloads that would require expending boosters so that they can instead keep them.

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Man rated Falcon Heavy? Not going to happen.

They decided to spend money on BFR, instead. Sensible, as crew FH has few uses.

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Propulsive landing of the Dragon 2? Not going to happen.

Wasn't worth the money, and they still might experiment with it on some cargo launches. Commercial crew is only 1 launch per year. Picking battles is called being smart. What's with the obsession with "promises?" Who cares, it costs you nothing?

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Dragon 2 to Mars? Not going to happen.

Yeah, again, in favor of BFR. They have limited funds, spend intelligently. ULA is happy to fly the same rocket for 50 years, they're not.

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Musk does change his plans, and his intentions. Yes, his long term goal of Mars hasn't shifted, but to be fair, Mars is still NASA's long term goal; so you can't say NASA has been changing their goal while ignoring the fact that like NASA, SpaceX is shifting towards the moon as well with Mars firmly in the future.

They are offering the Moon because NASA might pay for it. Unlike other contractors (SLS is just contractors, after all), they are developing this capability at zero cost to the taxpayer. Assuming it works, it obviates SLS, and makes it look like a huge waste of money. If Starship works at virtually any level, this is true.

The SpaceX goal has been Mars for people. Their vehicles have been designed to learn and figure out tech to achieve that goal, including a way to pay for it. Cutting loose dead weight absolutely furthers that goal. They won't make as much money on propulsive landing for crew vehicle? Kill it. Not worth spending on making FH a crew LV? Kill it. Not spending a few hundred million to fly Dragon to Mars, when they could accelerate BFR, instead? Kill it. Agility.

 

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ULA Delta IV Heavy. - Not Man Rated- Never will be

SpaceX Falcon Heavy. - Not Man Rated- Never will be

ULA Atlas HLV (looks like D IVH, but with atlas V), long proposed unsure if faster dev than the next 2). - Discontinued, no longer offered

ULA Vulcan (metal bending as we speak) - Distant future; unproven

Blue Origin New Glenn. - Distant future; unproven

Heavy lift. It's a rocket. Not a spacecraft. It throws it's cargo to a specific destination. It's function was always between the moon and Mars. Whether ARM, Lunar operations, or Mars missions. Alterations to the design (like BFR's development, shocking I know) has proven that it's not capable of all the promises made before the numbers were crunched (almost like BFR). So expectations were simplified. This isn't even unlike the Saturn V which was expected to launch a wide verity of things prior to it's completed assembly, and like SLS, it also had a wide range of uses as it was only a booster. It could've been utilized in preparing and assembling Mars missions, launching lunar space stations, launching lunar cargo, and that's just the tip of the iceberg. Oh, and the Saturn V was extremely inefficient and post Apollo 11, was only in operation to keep those jobs open. Since they had cheaper rockets that could launch heavy payloads (Titan IIIC, Titan IIIE+Centaur, Titan 34D, Delta III 3940, and all of which could've launched lunar cargo or lunar modules for far cheaper than the extremely cost ineffective, Saturn V.

Orion only needs heavier lift because it got bloated with SLS (over 20% heavier now than the 2005 RFP). CST-100 started out as an Orion bid, after all. Man-rating existing rockets (or under dev) is not that difficult if they want it done, they just haven't bothered because there is no need. Given that people will not fly on SLS until 2023, earliest, they have a little time if required to man-rate anything they like.

Edited by tater

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I am so with tater on this.

SLS isn't capable enough to perform any useful mission. It can't fly often enough to do EOR. It can't comanifest enough payload with Orion to perform useful beyond low earth operations. As an architecture it makes no sense.

A non-man-rated booster capable of boosting 180 tonnes to LEO 4 times a year with Orion going up separately? Now we're talking.

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