SLS evolves more towards ARES V...

[MKSheppard]

Remind me again why we incurred a 20+ month delay when Obama cancelled Constellation?

Link

The Space Launch System (SLS) is undergoing final refinements – known as trades – on a preferred baseline for the opening flights, with documentation showing a preference to debut the Heavy Lift Launch Vehicle (HLV) with four RS-25s on the core stage, instead of three. Should this become an approved configuration, it would allow for full utilization of the propellent that can be contained inside the stretched core.

Heh.

Meanwhile everyone ignores the elephant in the room, of an engine that can be brought back, due to a comprehensive line shutdown that included taping the recollections of key engineers and documenting everything...

[Uraniun235]

There is no actual desire in the administration or Congress to perform any of the missions for which a heavy-lift rocket would be suitable or necessary. The notion of astronauts returning to the Moon or pushing to Mars is a legend drawn upon by successive administrations to tantalize the public with the dream of recapturing lost glories, while throwing just enough money at contractors to keep their constituencies happy enough to keep voting for them but not enough money to actually accomplish those dreams.


I'm a big fat fucking nerd for huge space rockets and human spaceflight, but to be blunt I think modern manned spaceflight is basically a big scam at this point. Not even in the "lolololol going to the moon sure was productive" spirit of skepticism, but just the sheer fraud of "we're gonna throw money at it and not even get there." I think Obama's continued support of manned spaceflight is purely motivated by election strategy, and it would not surprise me in the slightest if (in the event of re-election) he turned around and ordered a stop to SLS development shortly after the election.

[Pelranius]

Apparently Obama believed everything the Augustine Committee said (such as the Ares V not being ready until the mid 2020s at best), so he figured it'd be better to have 70-100 ton payload rocket flying around by 2017.

That being said, I think Obama is for space flight, but it's the same level of interest that Nixon expressed: in his view, it is a nice thing to have and would go forward in an ideal world, but at the first sign of trouble or other national priorities rearing their heads, it will get dropped and kicked to the curb like a teabagger running in a Delaware Senate election.

[someone_else]

Another article on the same theme but with more info.

First, who is actually giving a shit about it:

At that press conference, held in a spartanly furnished committee hearing room on the ground floor of the Dirksen Senate Office Building (media and other in attendance had to stand for the half-hour event as there were no chairs in the room) Bolden was flanked by two key senators, Bill Nelson (D-FL) and Kay Bailey Hutchison (R-TX), the chairman of the Senate Commerce Committee’s space subcommittee and ranking member of the full committee, respectively; the two were the key authors of last year’s authorization bill and Hutchison in particular had been critical of NASA’s delays in announcing a design for the SLS.

Notably, at the press conference it was not Bolden who announced the design of the SLS but Nelson, who opened the press conference to describe what he called “the most powerful rocket in history.” He unveiled two artist’s conceptions of the SLS sitting on the pad at the Kennedy Space Center, showing what was clearly a shuttle-derived vehicle, although sporting a black-and-white job that harkened back to the Saturn V.

The costs:

Ultimately, NASA plans to have the SLS ready to fly for an uncrewed test flight by the end of 2017, along with the MPCV and associated ground support systems, at a cost of $3 billion a year through 2017. After that NASA would then human-rate the rocket for crewed launches, although Gerstenmaier did not give an estimate of the cost of that work. He added that NASA would work “almost immediately” to compete the design of the SLS boosters, and would design the core stage to be able to accommodate both solid- and liquid-propellant boosters.

Issues:

Gerstenmaier acknowledged that proposed budgets will be a major constraint on the program. “We’re trying to get to 2017 [for a first launch] and we see that as a pretty hard milestone of us,” he said. In order to meet that deadline, he said they may have to slow down other work that supports activities beyond 2017. “We may defer some of the upper stage work, we may defer some of the other capabilities in the out years that might push the second and third flights out to the right.”

And a very short comment on what is wrong about it:

The Space Frontier Foundation also criticized the SLS plan. “The amazing possibilities offered by engaging commercial space to lower costs and develop a sustainable long term infrastructure to support NASA space exploration, settlement and a new space industry have been trumped by the greed, parochialism, and lack of vision of a few congressional pork barrelers intent once again on building a government super rocket,” said Foundation co-founder Rick Tumlinson. “We’ve been to this party before, it was a bust then, and it will be this time as well.”

[Skgoa]

This design seems just as good now as it was 30 years ago. I remain somewhat skeptic about whether or not they will actually see it through, though. At this point NASA should just choose and implement ANY of the plans that have been thrown around. At least it seems "taxi to LEO" has been completely given to the commercial market, so NASA will continue human spaceflight no matter how or when the "cargo truck" clusterfuck comes to an end.

[ComradeClaus]

I've given up on Nasa. The fact russia can do things cheaper & daster shows how bad they fail, though the ESA fails even harder for having NEVER put a man in space, despite Rutan having done so (he should do a moon/mars shot next!)

And why aren't we using winged, air-breathing first stages? they're far more efficient! Rutan is using them & he's Mr Awesome Sideburnz!

BTW, could russia have reahed the moon before us w/ 2/3 soyuz launches? (1 for lunar module, 1 for C/S module) They already worked on rendezvousing in orbit right? like Vostok 5 & 6 which passed very close to each other. (they coud've rehearsed a fer rendezvous missions to prep for the moon shot)

[Pelranius]

NASA is giving commercial space a decent amount of support. SpaceX's Dragon capsule should dock with ISS next January (was suppose to be November this year but the Russian Progress launch failure threw the whole ISS docking schedule out of whack).

And the Russians are blathering on about Dragon docking with the ISS.

[phongn]

I've given up on Nasa. The fact russia can do things cheaper & daster shows how bad they fail, though the ESA fails even harder for having NEVER put a man in space, despite Rutan having done so (he should do a moon/mars shot next!)

The ESA doesn't really care for manned space. They're more about pure science. NASA's problems are really about how their mission and mandate changes with every new administration.

And why aren't we using winged, air-breathing first stages? they're far more efficient! Rutan is using them & he's Mr Awesome Sideburnz!

Rutan launches a suborbital vehicle, something NASA and the USAF did decades ago (also using a winged, air-breathing first stage!). If you want to do anything useful, you'll need a big rocket.

BTW, could russia have reahed the moon before us w/ 2/3 soyuz launches? (1 for lunar module, 1 for C/S module) They already worked on rendezvousing in orbit right? like Vostok 5 & 6 which passed very close to each other. (they coud've rehearsed a fer rendezvous missions to prep for the moon shot)

No.

[BrooklynRedLeg]

Waste. Of. Resources. Seriously, let the emergent private space companies do the manned mission stuff from now on. NASA either needs to be scrapped altogether or simply focus on unmanned missions like Cassini and the like. Let all the engineers, scientists and the like working on this dog go and work in the private sector. Either sell off or rent out all the existing launch facilities.

[Skgoa]

The problem with that plan would be that the private sector won't need a Heavy LV in the near future. Since you need one of those if you want to do serious science, the US doesn't really have a choice.

The ESA doesn't really care for manned space. They're more about pure science.

Thats not entirely true. ESA was founded precisely to ensure european access to space. ESA would love to do all kinds of high-profile manned missions. The big difference to NASA is in the two organization's attitude towards taxpayer money: ESA is very, very proud about its fiscal efficiency. That just means they have to dream smaller and have to accept a slower pace, in general.

[someone_else]

Since you need one of those if you want to do serious science, the US doesn't really have a choice.

That, or on-orbit refueling (cheaper, easier, faster by orders of mangitude in terms of development).

It's not like HLV are really required when you can send to LEO 80% of the HLV's payload mass (fuel) into multiple vehicles we have already.

[/shameless_advertising]

Seriously, let the emergent private space companies do the manned mission stuff from now on.

Or recognize that at the moment there is no real reason to send men anywhere.
Filling the moon with prospector unmanned rovers would be more profitable, and maybe manage to save manned missions in a future (with some luck).

[phongn]

Waste. Of. Resources. Seriously, let the emergent private space companies do the manned mission stuff from now on. NASA either needs to be scrapped altogether or simply focus on unmanned missions like Cassini and the like. Let all the engineers, scientists and the like working on this dog go and work in the private sector. Either sell off or rent out all the existing launch facilities.

Private space is disinterested in space exploration, so to do that would mean abandoning the interesting stuff. That may be reasonable indeed, but it's not a panacea.

Since you need one of those if you want to do serious science, the US doesn't really have a choice.

That, or on-orbit refueling (cheaper, easier, faster by orders of mangitude in terms of development).

Seeing as nobody has demonstrated orbital refueling yet, I don't see how that's cheaper, easier and faster. Further, if you want to move bulky and heavy stuff, small rockets just won't do it anyways. Besides, you can always combine the two for even more payload

[someone_else]

Seeing as nobody has demonstrated orbital refueling yet, I don't see how that's cheaper, easier and faster.

Estimates tend to hint at that, for example (fuel-depot architecture costing around half the Constellation-ish rocket mission architecture).
This PDF paper of the United Launch Alliance states "The total time from first launch to initial operational capability is anticipated to take approximately 6 months. The total launcher and depot hardware cost and services are expected be roughly $1B, including orbital checkout." at page 6. And goes on with "A basic exploration effort (Figures 3-5) enveloping conceptual crewed and robotic asteroid and cis-lunar missions conducted at a rate of two to four missions per year would require a total lift by propellant suppliers to LEO depot of roughly 200t at an approximate cost of under $2B/year,- the equivalent of nine Atlas 552 vehicles like the one that launched Pluto New Horizons."

Compare to this project, a stated cost of 3 billions up to a 2017 (hoped) maiden flight (15 billions total), that will require then an unspecified amount of time afterwards and likely a lot more money to become finally usable to do anything.
Also the idea of man-rating it is complete and utter idiocy.
There are more than enough man-rated rockets already, and doing it isn't trivial in cost and time.
Even Constellation was smarter (the capsule/people was on a man-rated smallish rocket, the space vehicle on a biggish not-man-rated rocket).

And before you say "it's all paperwork", please remember that at the moment even this monster rocket is more or less paperwork too, so we are on common grounds.

Besides, aggressively eyeballing everything I highly doubt the costs and times of development of an orbital fuel tank or a space tug (a modified upper stage like say a Centaur like most ULA's concepts) with some maneuvering systems, an arm and pumps will EVER approach the costs of developing a full-blown SHLV (with solid rocket motors, no less) more or less from scratch (as this proposal more or less is at the moment). The same about development times.
One of the key points is that there are already upper-stage engines that can do the job in a space tug/orbital depot, while you have to revive mouldy old projects or start anew if you want engines for a Big rocket.

I mean, why not give it a shot? even if it ends up needing 10 times more than the estimates (10 billions and 60 months-> 5 years) it will still be far cheaper and faster than (the estimated costs for) developing the abovementioned big rocket.
And can deliver much bigger things to more or less anywhere.

Of course lower development costs and less time will mean less money will go to the companies making it. And they don't really want that.

Further, if you want to move bulky and heavy stuff, small rockets just won't do it anyways.

I wouldn't call a 20-ton payload rocket "small", it's more a medium lifter.

Besides, what kinds of payloads would be too heavy and bulky to be launched in your opinion? Most stuff can be launched in 20-ish ton pieces (usually much less) from rockets we have already and assembled in space.

The issue is that with on-orbit assembly, you find that very big rockets aren't really needed. And goddamnit, we do have some kind of experience in on-orbit assembly after all. We even have a crewed space station that can do the job.

Let's give the ISS some kind of use every now and then.

Besides, you can always combine the two for even more payload

At roughly double the cost of using depots? Naah, not worth it.

Big rockets don't look very well in the open market. They are too expensive, and their big payload means they need a while to fill it up with sats and stuff that usually weights around 1-4 tons. Not to mention that most sats need to go to wildly different orbits, and doing it from the same rocket requires much more fuel for orbit insertion (i.e. a higher price because you now have less usable payload)

Fuel depots are instead very interesting for customers that want to send stuff to GEO.
Customer's rocket can lift up to say 5 tons to LEO but cannot go in GEO (too tiny payload to carry the fuel needed)?
Place a refuelling station in LEO, and even a cheap 5-tonner can do the job. Sats aren't that big.
So that's a helluva market that can be opened.

I think Canada launching an orbital refueling gizmo.

You mean this? It's a satellite refeulling tug. A big step in the right direction, but it's just related to what would be necessary here.
First, it is not working with rocket fuel (which is much harder to work with and is needed in much higher quantities).
Second, it is designed to go and reach satellites in their hapzard orbits, while a fuel tank is not designed to do much more than reboosts (with the outgassing H2) and fuel transfers to its ("dumb" as "they just stand still during the whole operation") customers (mainly upper stages).

This is what would do the first round of rocket fuel transfer tests. It's tiny and supposed to play with the liquid H2 that remains in the fuel tank of the expended stage of another payload it piggybacks the ride.

[MKSheppard]

AvLeak

CAPE TOWN, South Africa — NASA plans to open a competition in December for multiple, 30-month contracts to study strap-on booster upgrades for the planned heavy-lift Space Launch System (SLS), including an upgrade for the five-segment, solid-fuel strap-ons baselined as the initial boosters for the big new rocket.

One challenge for NASA engineers will be to design an interface that can link different booster types to the SLS core stage, according to William Gerstenmaier, associate administrator for human exploration and operations. The SLS will be the vehicle NASA uses to send humans beyond low Earth orbit.

“Our vision is we’ll have an interface that’s generic, and we’ll be able to carry potentially different boosters and change them out as needed,” Gerstenmaier told a session of the International Astronautical Congress here Thursday. “So we could go compete in the future, maybe downsize if something’s easier for a mission that requires less thrust. We have some variability there, so if we do our job right, we’ll have the ability to change the boosters that sit on the side. That’s our ultimate goal. We’re not going to pick one.”

Modular boosters is something easier said than done. The Aerothermo and integration costs with each booster type would be a steep wall to be climbed.

“It turns out that to get to the 130 metric tons, we’re going to have to redesign the five-segment booster as well,” Gerstenmaier says. “We have to go to potentially a composite case, away from our steel case to save some weight, and we might need to make a propellant change to use the more energetic propellant that sits in the solid rocket motor. So even if we go continuous solids, we’re going to have to make a pretty significant change to the solid-rocket booster segment.”

The competition for an advanced booster will begin in December with study-contract bidding that is likely to include ATK, manufacturer of the current solid-fuel boosters, and a team that includes Aerojet, which has plans to upgrade the Russian-built AJ26 NK33 LOX/kerosene engine it modified for the Taurus II launcher that Orbital Sciences Corp. will use to send cargo to the International Space Station.

“We’re not really ready to step up to the booster activity right away with a full-up competition,” Gerstenmaier says. “We think there’s some technology that needs to get explored and understood as we go forward. We think we also need to define a little bit better the core interface with the solid rocket boosters or the liquid rocket boosters, so we have that as a design condition. So we’re going to have kind of a study phase, with potentially multiple contractors participating in that study phase for a period of about 30 months or so, and then we’ll roll right into the actual competition. But the idea is to have the new booster system available, probably in about the 2019 time frame.”

This is a really really good bait and switch. They sold RAC-1 Shuttle Derived Heavy Lift as something that could be cheaply and affordably built using parts left over from Shuttle, and now they say they need to do all new advanced new SRBs to meet the 130 ton evolved goal.

At this point, what reason is there to continue with SD-HLV if we keep having to redesign, redesign, redesign things; as opposed to the clean sheet RAC-2 architecture which used F-1A?

[Skgoa]

Because a bunch of fucking civil servants have forgotten every lesson rocket engineers learned back in the 60ies and 70ies? There is a funny little factoid going around in rocket science circles: the greatest achievement of the Space Shuttle project manager was that he managed to stave off any kind of feature creep during the developement process.
I really hope for NASA's sake they don't get lost in unneccessary complexity. Unfortunately, the systemic problems that doomed constellation seem to not have been solved.

[Uraniun235]

I was under the impression that part of what contributed to the bloated size of the Space Shuttle orbiter were the added Air Force requirements for payload size, cross-range and polar orbit.

[Skgoa]

Take a minute to think about how much worse it could have been.

[phongn]

Because a bunch of fucking civil servants have forgotten every lesson rocket engineers learned back in the 60ies and 70ies?

No. Political reality demands that we have some absurd shuttle-derived launch vehicle.

[someone_else]

Cool, it's becoming something "loosely inspired from" shuttle.

An actual derived vehicle ("cheaply and affordably built", more or less) would be something like DIRECT. That is a Heavy lift vehicle actually reusing most parts from Shuttle launch system. After all, the shuttle orbiter weighted 110 or so tons at lauch, if you remove the orbiter and use the same stuff to make a rocket... you have around 100 tons of payload. And if you don't man-rate the RS-68 you can use them instead of SSMEs. It will not be man-rated, but making a man-rated Delta IV or Atlas V is easy (the most expensive stuff was already payed for with Constellation's escape tower), or just wait for SpaceX to man-rate falcon 9.

But the goal is paying someone, not making rockets.

[Skgoa]

phong: How does that connect to "people introduce unnesseccary complexity and immediately negate the every advantages of what they tried to achieve"? At this point, I would just take the hit on payload instead of redesigning the boosters.

[Skgoa]

Cool, it's becoming something "loosely inspired from" shuttle.

An actual derived vehicle ("cheaply and affordably built", more or less) would be something like DIRECT. That is a Heavy lift vehicle actually reusing most parts from Shuttle launch system. After all, the shuttle orbiter weighted 110 or so tons at lauch, if you remove the orbiter and use the same stuff to make a rocket... you have around 100 tons of payload. And if you don't man-rate the RS-68 you can use them instead of SSMEs. It will not be man-rated, but making a man-rated Delta IV or Atlas V is easy (the most expensive stuff was already payed for with Constellation's escape tower), or just wait for SpaceX to man-rate falcon 9.

But the goal is paying someone, not making rockets.

If you look at DIRECT's evolution, you can actually see the thought processes behind many of those choices. They haven't brought much new to the table, though. In the end, their definition of SD-HLV was simply not exactly what NASA wanted.

Now, lets take a moment to do a quick overview of the alternatives:
- Delta/Atlas: They exist, they are military. Two reasons why NASA will not go for them. NASA wants an entirely new rocket that has potential to grow and that they have full control of. As long as NASA has the funds to do that (and they barely can scrape those funds together), they should do that. Also, several politicians aren't going to let NASA take their business away from established suppliers like ATK.
- RS-68: While on paper its promised to be a great engine, the base version (i.e. the one in actual existance) is not sufficient. Thus, the engine would need a certain amount of time and money sunk into it. Even if NASA takes the decission to develop it right now, it's not going to be available for the "Block 1" launches. IIRC there is a political mandate to launch no later than 2017 and NASA really doesn't have the time or money t go "Lets bet everything on this cool idea for an engine we have drawn on a napkin. What could possibly go wrong?"
- Falcon 9: That's the point of NASA funding commercial space. Falcon 9 (or any of a number of rockets made by SpaceX's competitors) will provide reliable and cheap access to LEO. At this payload level, commercial launches can provide the economies of scale neccessary to keep cost down. Commercial launch providers will not provide Heavy Lift launch vehicles, though. So NASA will have to design their own. And of course there is the problem of Falcon 9 existing, being to small and not using shuttle derived technology.

IMHO NASA was on the right track with their studies. They have the choice of either starting with a clean sheet of paper or using what they have lying around. We can argue all day and night about whether or not the other two design teams were only to pretend NASA had not made up its mind*, but given the fiscal reality it is not that surprising they ended up going with what everyone should have seen coming back when people called for Ares I to be axed.


* I find some of the loosing designs too ridiculous to be anything more than "we looked at alternatives!"

[Number Theoretic]

Actually, SpaceX might be able to provide a heavy lift launch vehicle, if there is demand for it and they get the time to develop suitable engines. According to Wikipedia, their Falcon XX concept vehicle could be able to lift 140 tons into LEO. The article even speculates about a possible extension to that, "Falcon XX Heavy" with a whopping 460 tons payload.

And concerning manned spaceflight: their Dragon capsule already flew into orbit (unmanned though) in December 2010 orbited twice the earth and returned safely.

[MKSheppard]

Delta/Atlas: They exist, they are military. Two reasons why NASA will not go for them.

It's the other way around. USAF controls them, and does not want EELV production diverted to NASA. The USAF remembers what happened in the 1980s and will do anything to prevent that catastrophe for military space from happening again.

RS-68: While on paper its promised to be a great engine, the base version (i.e. the one in actual existance) is not sufficient.

Actually, it's a great engine and is a direct result of NASA's efforts in developing a cheap, low cost expendable SSME; which became STME, and then RS-68.

NASA really doesn't have the time or money t go "Lets bet everything on this cool idea for an engine we have drawn on a napkin. What could possibly go wrong?"

So I guess all those launches of Delta IV with RS-68s have never happened?

DIRECT kept claiming RS-68 needed to be developed into a regenerative version in order for it to be used with SRBs, in their fuliminations against ARES V; but even regenerative engines had problems with base heating.

When they investigated strapping solid rocket boosters to the side of a S-II stage from Saturn V, they found that the base heating environment was unnaturally intense; and their solution was to shove insulated jackets onto the J-2 engines and design a flat heat shield that would protect the rest of the J-2s from the SRB heat.

[Skgoa]

RS-68 might be a great engine by everbody else's standards, but it's worse than RS-25. RS-68B (the version that is promised to reach RS-25's Isp) does not exist, yet. RS-25D does exist, NASA has 16 of them lying around. RS-25E (aka Block III) does exist and costs only $25 millions per engine. Since production tooling is being adapted right now, RS-25 will benefit from the same economies of scale as RS-68 an J-2.

[Skgoa]

ghetto edit:

My point is that RS-68 as it exists right now has a significantly worse Thrust-to-Weight ratio and specific impulse compared to the engine NASA has been using for 30 years. RS-25 is the better choice from a performance POV, that's a simple fact. I agree with you that RS-68 might be a more economical choice compared to new RS-25Ds. But since the first four launches will use up existing engines that don't need any development or testing work, and after that the significantly cheaper RS-25Es will be used, it makes sense to go with SSMEs. Even if we accept that RS-68B will reach the performance of RS-25E, saving only $11 million per engine (lets be generous and say $50 million per launch) is not enough to justify the additional cost and risk of having to develop it.