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NASA Human Landing System


tater

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2 hours ago, tater said:

For crew missions they really should not be stuck with the awful series of Oberth burns ICPS is forced to do. 2 ICPS (RL-10) burns, then another small burn with the OMS engine on Orion.

But remember, SLS is sooooo safe. It's so safe, in fact, that it cannot pull off a free-return trajectory without sacrificing so much of Orion's propellant that Orion can no longer enter lunar orbit.

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On 5/1/2021 at 7:25 PM, tater said:

4xRL-10

2 hours ago, sevenperforce said:

TLI is not terribly high energy; you need good thrust for your final push to orbit or you burn too much of your propellant in a lofted trajectory.

Hmmmmmmm.......

what if....

897rCZg.jpg

:wink:

 

 

 

Edited by Spaceman.Spiff
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3 minutes ago, sevenperforce said:

But remember, SLS is sooooo safe. It's so safe, in fact, that it cannot pull off a free-return trajectory without sacrificing so much of Orion's propellant that Orion can no longer enter lunar orbit.

At least presumably with EUS it can manage the one burn.

To be fair, ICPS was only supposed to be used for the one, uncrewed mission... now we see why.

 

42 minutes ago, Spaceman.Spiff said:

what if....

The Saturn I was a fantastic rocket.

400kN for those 6 RL-10s.

 

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4 hours ago, Spaceman.Spiff said:

Hmmmmmmm.......

what if....

:wink:

Expander-cycle engines are great for high-energy orbits. They are lightweight and ridiculously efficient and just absolutely amazing pieces of engineering. Even if they are expensive.

They just really, really suck for medium-energy high-mass payloads.

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On 5/2/2021 at 8:25 AM, tater said:

NASA doesn't build anything. They hire "corporate dudes" to do it for them.

And some dudes may be more equal than others.

Also it's absolutely coincidentally that Axiom consists of the former NASA guys (and probably some now-NASA guys can be future-Axiom ones).

9 hours ago, tater said:

Dynetics? This seems like the ideal role for their concept... if it could actually land (making a new crater doesn't count)

Currently their soft landing count is same, but the Dynetics modules look definitely more stable on ground.
And they don't need to move vertically every step.

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4 minutes ago, kerbiloid said:

Also it's absolutely coincidentally that Axiom consists of the former NASA guys (and probably some now-NASA guys can be future-Axiom ones).

Nah, no coincidence. People who wrap up careers at NASA usually go on to work in related fields. Is that corruption? No.

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2 minutes ago, kerbiloid said:

And some dudes may be more equal than others.

Also it's absolutely coincidentally that Axiom consists of the former NASA guys (and probably some now-NASA guys can be future-Axiom ones).

People from the DoD and NASA always move back and forth. Gerst is at SpaceX after all.

I don't honestly care that much, NASA's budget is I think less than the school system in the City of NY. Noise.

Since HLS is part of Artemis, and Artemis involves other countries—why can't they pony up an amount weighted to their size that equals NASA? It's not like NASA is a lot of money.

 

2 minutes ago, kerbiloid said:

Currently their soft landing count is same, but the Dynetics modules look definitely more stable on ground.

It's easy to soft-land a foam core mockup. Maybe they can learn from it and make their actual vehicle a few tons lighter*?

 

2 minutes ago, kerbiloid said:

And they don't need to move vertically every step.

With a negative mass margin, they can't move any way at all.

 

 

* I think the requirement was initially 2 crew, later 4, plus 800-somethign kg of additional cargo, so they clearly need to shed at least a couple tons.

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14 minutes ago, SOXBLOX said:

Nah, no coincidence. People who wrap up careers at NASA usually go on to work in related fields. Is that corruption? No.

Exactly.
So, the people from the organization which had never built a module itself, are better specialists in the module building than the corps who do this since the Earth appearance, and easily win the tender(s).
And probably they will hire former NASAns  than former whoever-else.

Everyone should care of his pension, of course, that's not something bad...
Also this is not an insider info or so, just their friendy talks about business news.

11 minutes ago, tater said:

is at SpaceX after all.

Why I'm not surprised.
A NASA protege company which is becoming a basket where NASA tends to put all eggs.

Say, lunar Starship flies.
Then who needs LOP-G, Orion, SLS, etc.

There will be only SpaceX affiliated with NASA and the Axiom home for the NASA veterans.
Looks wise, why not.

Let's imagine than Starship won't.

Edited by kerbiloid
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3 minutes ago, kerbiloid said:

Why I'm not surprised.

?

Every single US defense contractor has been like this since forever.

Guess what, if your company sell linens to hotels, you probably employ ex-hoteliers. It's not because Hilton likes buying stuff from an employee that left them, though perhaps that guy still has contacts to get his foot in the door. More likely the guy who used to run the hotels... knows what hotels actually need in terms of linens, and gets the company he now works for to make a product that his old job would love to buy.

People work for the labs here in NM (Sandia, LANL, Phillips (now AFRL)). Guess what, they move back and forth with contractors as well. Maybe they go from AFRL to Honeywell, someone they know has an opening at LANL, and they want to get out of ABQ and move up towards Española, so they take that. Happens all the time.

The rocket companies poach from each other, too. The head (?) of the HLS at BO was hired away from SpaceX (you'd recognize her from the live streams... Lauren (last name escapes me)).

What difference does it make? Slight differences inexactly where my tax money goes to? NASA is a tech jobs program, so going to tech jobs is a win.

12 minutes ago, kerbiloid said:

Say, lunar Starship flies.
Then who needs LOP-G, Orion, SLS, etc.

There will be only SpaceX affiliated with NASA and the Axiom home for the NASA veterans.
Looks wise, why not.

All I personally care about is capability. Maybe cheap mass to space means NASA can stop bothering with launch, and build spacecraft, instead?

Also—NASA vets probably work for every single company that ever bids for contracts with them.

Lightfoot is on the advisory board of Firefly.

O'Keefe worked for Airbus after he left NASA.

(those are just some of the head Admins, loads of other NASA employees move to industry or from industry to NASA).

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3 minutes ago, tater said:

All I personally care about is capability. Maybe cheap mass to space means NASA can stop bothering with launch, and build spacecraft, instead?

Something like that was said about Space Shuttle in its time.

Happily (for them), they failed the idea of replacing every launch vehicle with Space Shuttle (just to provide it with payloads), so when the Shuttle program was once delayed for years, then cancelled, they had several alternative rockets still flying.

(Obviously, I don't care which one of the US rocket manufacturers wins, saying all of that just as a KSP user).

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25 minutes ago, kerbiloid said:

Something like that was said about Space Shuttle in its time.

Happily (for them), they failed the idea of replacing every launch vehicle with Space Shuttle (just to provide it with payloads), so when the Shuttle program was once delayed for years, then cancelled, they had several alternative rockets still flying.

(Obviously, I don't care which one of the US rocket manufacturers wins, saying all of that just as a KSP user).

Shuttle was a cost-plus government project. Shuttle dated from an era when the US government was the only launch provider in the US by law. The initial goal was to fly Shuttle weekly. The reason? That's the only way the cost could be below existing rockets like Titan. It never worked as planned. I'd argue it didn't precisely because it was a government program. The incentives were never there to change anything not broken. Certainly none existed to really innovate.

Since US launch was privatized in the late 80s, that is simply no longer the case. There are a raft of smallsat launch companies (most will fail), there's NG, ULA, SpaceX, BO all in the medium+ lift business. SpaceX is not building Starship for NASA, even if they are happy to sell services to NASA using it. Any sales are incidental.

The launch market is in fact pretty tiny. What is it, $20B a year? Apple makes 1-1.5X that a month. SpaceX is not really trying to make all the launches to make money. When actual competitors arrive, it drives costs down a little, and makes the launch business worth less. The only way for launch vehicles to expand the annual space market is to change it utterly.

There is only one space market for Earth, that's satellites. Some commercial, some gov. SpaceX can launch all the commercial, some of the gov.

Past Earth the only current customer is government, and the only government with real money to spend is the US—and even that is a tiny chunk of money, a few billion a year at most. Under a week of Apple level revenue for the entire thing. Chump change.

How to make real money in space? I have no idea, except it's not sats, and not selling launches to NASA, you could capture the entire NASA budget related to launch/exploration and it's nothing serious. Maybe you expand to mining? Maybe their goal is not in fact "making" money, but making just enough to fly rockets (to Mars I guess)? Maybe that goal is to let others start doing things that needs rockets so they can build and fly more of their own?

Edited by tater
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Spoiler
3 hours ago, tater said:

Shuttle was a cost-plus government project.

A government can get plus from vatious projects, and not all of them are spaceplanes.
As well, NASA is not the only calf at the government's ... a little yellow-and green bird like a sparrow

Afair, when NASA post-Apollo budget was cut, they had a choice between a orbital station and a spaceplane (smaller than Shuttle and liquid-boostered).
As Pentagon was needed something like spaceplane, too (to rotate KH-11 for repair presumbaly yearly or so), so NASA chose the spaceplane,sacrificing a post-Skylab station, to make/let Pentagon to be a financial locomotive of the whole project.

Since it should have enough room for the railroad-sized KH, they enlarged it to the actual size.
And as it should be used weekly and spend money, it was an advantage because allowed to lift any other payload of standard railroad dimensions.

Additionally Pentagon forced NASA to replace the liquid boosters (more appropriate for a crew system) with the solid ones, from the Pentagon's rocket buddy, Thiokol, to support the native manufacturer,

The payload mass was defined by "what's to be deorbited", rather than "what's to be lifted", so it's payload was actually "15 t from orbit" (a typical mass of heavy spysats, including the first-generation orbital stations).
On the other hand, "15 t down" resulted in "30 t up", though Shuttle never actually lifted so much.

Having a 30-t weekly-flying reusable shuttle would cannibalize all other cargo launches (hi, Space-X!), so they decided that this super-cheap and super-capable should be the only lifter (hi, Starship!), replacing other rockets.

So, the Shuttle was to be the only capable launch vehicle (hi, Starship!), the only spaceship (hi, Starship, greetings to Drago!), it would weekly get up and down with all kinds of trivial payloads (hi, Starship!), delivering among them heavy spysats and other milsats up and down (hi, Space-X!), becoming a total monopolist (hi, Space-X!)

But since KH appeared to be much tougher than it was planned, the need in thei yearly rotation disappeared.
SDI, like all other the gorgeous military space projects, sank in debates and budget negotiations, especially since the lack of a worthy aim caused by the known political events.

(Like if somebody really believes that SDI actually was a tricky fake to fool the Russians and make them pay for countermeasures.
The Russians were doing that before the first sputnik had flown, and before anyone knew the SDI abbreviation.
While Horizon, Orion, and Lunex appeared long before Russians had ICBMs).

And since the Shuttle onstruction appeared to be so fragile and complicated that its interflight servicing turned into the disassemble-replace-assemble, the "weekly" turned into "halfyearly", making Shuttle the most exappendix vermicularisve known lifter with payload of two Protons never used completely. (30 t of cargo + 10 t of cabin, i.e. a crew capsiule for eight).

If/when Starship with its thirtypack of engines faces similar troubles. it will put into troubles everything related, because other rocket providers need payloads (eaten by Starship) and money for their technological breakthroughs (like the lunar programs) with no obvious profit from the market.

4 hours ago, tater said:

How to make real money in space? I have no idea, except it's not sats, and not selling launches to NASA

Probably, it will get possible decades later, when the fusion and the remote power transfer make things change, but unlikely now.
Including any kind of the lunar mining.

4 hours ago, tater said:

 Maybe their goal is not in fact "making" money, but making just enough to fly rockets (to Mars I guess)? Maybe that goal is to let others start doing things that needs rockets so they can build and fly more of their own?

Imho, nothing that costs money, is actually made for ideas (including the Martian and the lunar flights).

The businessmen spend money to get more money and don't care much of the global aims.
They are interested in local possibilities, even when they dream about global philosophical things.

The bureaucrats (administrative personnel) perform administration tasks and don't care about the aim, too.
They are just cogs and wheels in the stable mechanism, or a liquid in a system of pipes trying to fill the empty space, to drain down and cause as less perturbations as possible,
Even if they play KSP and have a telescope at home.

So, when all kinds of anything related to space get occupied by the same monopolist,
and, say, the perfectly working LEO Starship failes the lunar missions (they can't debug it on the Earth by Alt-F12, gravity=1.62), other companies of course may have their own alternatives, like SLS, Orion, LOP-G, but all of them will have to start it from scratch.

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1 hour ago, kerbiloid said:

The businessmen spend money to get more money and don't care much of the global aims.
They are interested in local possibilities, even when they dream about global philosophical things.

Musk is not doing SpaceX for business, he's doing business for SpaceX.

If that makes sense. It really is the only way to understand them. As I say in most SpaceX threads, "I'm not a colonize Mars guy." A decent % of the people at SpaceX are colonize Mars people.

 

1 hour ago, kerbiloid said:

The bureaucrats (administrative personnel) perform administration tasks and don't care about the aim, too.
They are just cogs and wheels in the stable mechanism, or a liquid in a system of pipes trying to fill the empty space, to drain down and cause as less perturbations as possible,
Even if they play KSP and have a telescope at home.

Yeah, probably.

 

1 hour ago, kerbiloid said:

So, when all kinds of anything related to space get occupied by the same monopolist,
and, say, the perfectly working LEO Starship failes the lunar missions (they can't debug it on the Earth by Alt-F12, gravity=1.62), other companies of course may have their own alternatives, like SLS, Orion, LOP-G, but all of them will have to start it from scratch.

This is a concern I simply don't have.

We're a long way from having an entire exploration program entirely served by one vehicle such that any future accident that shuts it down some months is troublesome.

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8 hours ago, kerbiloid said:

Something like that was said about Space Shuttle in its time.

I get that the Shuttle didn't work as intended. You keep pointing that out gleefully. But it was still a capable vehicle, and one of the most important in spaceflight history, after the Saturn V.

8 hours ago, kerbiloid said:

Why I'm not surprised.
A NASA protege company which is becoming a basket where NASA tends to put all eggs.

Um, no. It's cheap. Common sense says people prefer "cheap" if money is a priority. And NASA does hand out contracts to other companies. If they want money, they've gotta undercut SpaceX, or get close. That's called a free market.

8 hours ago, kerbiloid said:

So, the people from the organization which had never built a module itself, are better specialists in the module building than the corps who do this since the Earth appearance, and easily win the tender(s).

Than who? And these people are engineers. They're doing engineering. What's sinister about that? And who would you rather have paying them? Should they work for, say, Roscosmos, so as not to look like they're (gasp!) getting money from NASA?

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14 hours ago, Spaceman.Spiff said:

Hmmmmmmm.......what if....

Spoiler


897rCZg.jpg

 

 

:wink:

Something else to keep in mind -- those six RL-10s on the top of the Saturn I were RL10As without nozzle extensions (you can see if you look closely) so they were completely regeneratively-cooled, allowing them to be clustered like that.

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18 hours ago, tater said:

Dynetics? This seems like the ideal role for their concept... if it could actually land (making a new crater doesn't count). maybe they could hack the crew compartment back to be a taxi, no excess capacity or space, since the crew would exist, and then climb aboard a lunar Starship left as the habitat?

Honestly I think their design is better used to lower down freight... like rovers etc.

They could then more easily change the tank sizes I suppose, and the weight limit of the remaining space be fitted to the density of cargo rather than crew compartment.

13 hours ago, tater said:

To be fair, ICPS was only supposed to be used for the one, uncrewed mission... now we see why.

With "Interim" in the name it's really not meant for the main mission.

8 hours ago, tater said:

When actual competitors arrive, it drives costs down a little, and makes the launch business worth less. The only way for launch vehicles to expand the annual space market is to change it utterly.

There is only one space market for Earth, that's satellites. Some commercial, some gov. SpaceX can launch all the commercial, some of the gov.

[...]

How to make real money in space? I have no idea, except it's not sats, and not selling launches to NASA, you could capture the entire NASA budget related to launch/exploration and it's nothing serious.

I guess it explains Starlink... there're way more Starlink launches than there are external commercial launch contract for F9 already.

Edited by YNM
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1 hour ago, SOXBLOX said:

Um, no. It's cheap. Common sense says people prefer "cheap" if money is a priority. And NASA does hand out contracts to other companies. If they want money, they've gotta undercut SpaceX, or get close. That's called a free market.

Cheap for SpaceX doesn't turn into cheap in general unless there is competition... the business case is interesting. As I aid, completely capturing the entire global launch market (the part available to non-state actors) is still not really a large amount of money. There are a lot of players worth a lot of money for what is a nothing-burger of business. Bezos wanting BO for "business" is not a thing, Amazon makes almost $400B/yr, BO capturing half the entire launch market would be a little over a week of Amazon revenue.

If there is competition... the market is worth less, not more.

 

30 minutes ago, YNM said:

Honestly I think their design is better used to lower down freight... like rovers etc.

They could then more easily change the tank sizes I suppose, and the weight limit of the remaining space be fitted to the density of cargo rather than crew compartment.

This is more on topic for the thread.

I loved the Dynetics lander. It was my fave of the choices since I assumed SS had no chance. One way or another it needs more propellant, less mass, or better (higher Isp) engines. Or a combination.

I said in some thread that the ideal "SLS based" sustainable lunar architecture would send crew using distributed launch and EoR, and SLS would maybe send a huge habitat ahead. The landers would then be sortie landers. LLO to the surface, minimal consumables, if the trip each way from and to orbit is a couple hours, then it has that duration with a little margin. The crew does it's surface living in the hab, landers are bare bones.

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I also would have picked Dynetics 1st place before reading the selection report. I thought it would be cheaper than BO, with fewer moving parts and a nice underslung module.

But it's hard to argue with a negative mass budget likely to get more negative, not less.

I also assumed SpaceX were 2nd place at best due to being the biggest schedule risk , but the selection document actually placed them as least risky and most likely to make the nominal schedule. I found that surprising in particular.

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1 hour ago, tater said:

I said in some thread that the ideal "SLS based" sustainable lunar architecture would send crew using distributed launch and EoR, and SLS would maybe send a huge habitat ahead. The landers would then be sortie landers. LLO to the surface, minimal consumables, if the trip each way from and to orbit is a couple hours, then it has that duration with a little margin. The crew does it's surface living in the hab, landers are bare bones.

My own thinking was probably send basic stuff to the surface first (like habs etc). At the same time, make the station, and make all missions only to there first until we're ready with the surface ops. If we want to put the surface crew rotation at, say, 7 months each with 5 months on the surface, then we probably can do away with only 2 crew landers, 1 for contingency. Then we can have a shuttle between the station and the surface for resupply and retrieval of stuff. Crew rotation also only needs a craft that can dock with the station rather than reach surface.

Figure that this isn't too far off what they'd do on the ISS. We do need refuelers though.

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1 hour ago, RCgothic said:

I also assumed SpaceX were 2nd place at best due to being the biggest schedule risk , but the selection document actually placed them as least risky and most likely to make the nominal schedule. I found that surprising in particular.

There are more than technical delays to consider

1 hour ago, tater said:

Well, SpaceX is building the thing regardless of NASA, so...

This means that the(expected) lawsuits about selection and other things, while they would likely delay other providers, will not really affect the Starship schedule, and already having hardware that has left the ground probably helps too.

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18 minutes ago, Terwin said:

This means that the(expected) lawsuits about selection and other things, while they would likely delay other providers, will not really affect the Starship schedule, and already having hardware that has left the ground probably helps too.

Yeah, the tricky bits of Lunar SS are unrelated to lunar SS, it's SS orbital reuse and retanking.

Edited by tater
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5 hours ago, tater said:

I loved the Dynetics lander. It was my fave of the choices since I assumed SS had no chance. One way or another it needs more propellant, less mass, or better (higher Isp) engines. Or a combination.

I said in some thread that the ideal "SLS based" sustainable lunar architecture would send crew using distributed launch and EoR, and SLS would maybe send a huge habitat ahead. The landers would then be sortie landers. LLO to the surface, minimal consumables, if the trip each way from and to orbit is a couple hours, then it has that duration with a little margin. The crew does it's surface living in the hab, landers are bare bones.

The low-slung effect seemed REALLY promising to me. A bare-bones lander with egress at the surface could enable transfer to a pre-placed hab via pressurized rover.

Just imagine -- Starship reusably delivers a big surface hab with its own airlock and a couple of semi-autonomous solar-powered pressurized rovers with docking ports in the tail. Orion meets the Dynetics lander at Gateway and you hop in. Basically it's just a lander can, nothing more, with two or three sets of drop tanks. It only needs consumables for the trip down and the trip up. It takes you down to the landing site (dropping tanks along the way) and then once the dust settles the pressurized rover pulls up, attaches to the front of your lander can, and you climb in and drive over to the hab which is a safe distance away.

At the end of the mission you can climb back in the rover and repeat the process in reverse. Plus, you get back to the Gateway and it can replace your tanks with a Canadarm for the next mission. Maximum simple reusability, minimal complexity, no wasted mass being dragged up and down.

There really is a dearth of good engines in that particular space, though. Like, a real lack. We don't have many options for hydrolox engines at all...until BE-3U flies, the only American upper stage hydrolox engines we have are RL-10 variants, I think. Vinci looks very promising even if that long combustion chamber is scary.

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3 minutes ago, sevenperforce said:

There really is a dearth of good engines in that particular space, though. Like, a real lack. We don't have many options for hydrolox engines at all...until BE-3U flies, the only American upper stage hydrolox engines we have are RL-10 variants, I think. Vinci looks very promising even if that long combustion chamber is scary.

The issues with hydrolox prop depots are a thing as well. Methalox is slightly better boiloff wise, and with SS functioning (just as a mass to LEO thing), methalox starts looking like the prop to use. Given the tiny size (compared to SS), a single SS tanker could deliver many sorties of props for Alpaca.

Relativity Space has an engine about like RL-10 in thrust, that does ~360s with CH4/LOX. A 40t wet, 12t dry lander could do the round trip, and with 28t of props. 1 tanker could sit there as a tanker and multiple missions could be flown.

The Lunar SS could just sit there as a base. That or a variant that stages off the payload section with some landing engines on it could make a hab closer to the surface (to be partially buried).

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