2.5 launch architecture?

[Robotbeat]

Now that it looks like the Ares I is going ahead no matter how rediculous it is at this point, could a 2.5 launch architecture make sense?

You still don't have to manrate anything other than the Ares I which already has had hundreds (?) of millions of dollars spent on it. The Ares V is rediculous. It sounds cheaper to me to just do an Ares with standard 4-segments, which might only get around 100 tons to LEO. Heck, do we even need an upper stage, then? Sure, without an upper stage we could only get like 60 tons to orbit, but that might be enough to send Lunar base modules to the surface.

In this way, an ISS-optimized Orion could be used (except for the heat shield). All the lunar-specific stuff would be launched seperately by two smaller Ares V-type vehicles. Some lunar missions (base replenishment) could get by with only one mini-Ares V.

It seems that this might make everything closer to the shuttle as far as weight/size limitations and logistics and existing architecture are concerned, but still assumes that Ares I emerges somewhat similar to what it is planned for now (in spite of thrust oscillation, aerodynamic instability of having a high center of pressure, etc.). Even if you have to use an EELV or a Dragon architecture, this could still work without changing the mini-Ares V vehicle.

Not only that, but you still have a launch architecture that can get you to Mars without a billion tiny launches. The launch fairing size of a mini-Ares V could still be large enough for new big space telescopes and, with some bulging, Martian heat shields. Plus, more launches means better economics.


It seems to me now that a Direct sort of approach just isn't going to happen since Ares I is so far down the road. Perhaps Ares I should be canceled, but I'd bet that if it was canceled, so would any near future lunar plans, at this point (unless there already was a replacement for Ares I--like EELV or Dragon--and also a large launcher like an Ares V or a mini Ares V already built).



PS, I'm new here. Be easy on me!

[tankmodeler]

If you split into 3 launches (Bugger this 2.5 launch crap. A half launch is one that ends up in the Atlantic and no-one wants that.) what goes where? Already Ares I doesn't seem to be able to haul a fully loaded lunar insertion-capable Orion to orbit, but let's assume that it could. So then you have the EDS and the Altair lander. Last time I looked, neither was 100 tons, so you could get away with a launcher that was well under 100 tons for the EDS and a launcher that is about 50 tons for the Altair, but wait, that's three different sizes!

So, we have a 25 ton Orion plus it's escape tower, a 45 ton Altair & a 70-80 ton EDS plus associated shrouds & fairings. What would a sensible way be to split up that lot, then, with out breaking the national bank. I know, put the 80+ tons of EDS on one rocket & the 80+ tons of Orion & Altair on another rocket of the exact same design! That's novel. Oooo and maybe we could use actual shuttle hardware in the new rocket, and not change the manufacturing or launch infrastructure and not change the tank diameter and, and, and...

Oh, never mind, that's a J-232.



BTW, Robotbeat, I'm not trying to take a poke at you or anything, just taking a sarcastic look a the mess we're in with Constellation at the moment. If the load naturally split itself into 3 approximately equal loads that we could launch on three rockets of the same design, that would be a good option. I don't think the mission payload does break up into three roughly equal parts, though (I'm willing to be proven wrong). Not without refueling or multiple dockings, extensive orbital assembly or the like. And NASA has already put the kibosh on most of that.

Paul

[Patchouli]

  Another three launch setup might be to use the Delta IV-H to launch a full 25 to 30T lunar Orion.
Then use a three CCB Atlas V,F9-H with a Centaur or Jupiter 120 to launch Altair and then a J-232 to launch the EDS.

If the Jupiter 232 is not available it becomes a four launch setup since the EDS would have to be split between two 45T to 50T launches.
Breaking stuff down into parts smaller then 45T becomes unpractical unless everything done with Constellation including Orion is thrown out.
A much lighter crew vehicle and lander would have to be used such as Dragon and the horizontal lunar lander.
Though if you have the Jupiter 232 you can just do a two launch setup.

Maybe Obama will send one of his tiger teams to NASA and get rid of all the idiocy we have been putting up with.
I see no reasons at all to continue Ares I other then political ones.

[Robotbeat]

Well, an Ares V without a second stage and only the four-segment solid rocket boasters (plus four or five RS 68s, of course) could put roughly 50+ tons in low earth orbit. Generally, in rocketry, the second stage costs at least as much as the first, and the four-segment SRB are already developed, so this should be much cheaper to both develop and fly than the Ares V. And you could use the much cheaper 8.4 meter diameter first stage, which will (theoretically) reduce development time and cost because it uses the same diameter as the shuttle's ET. I will call this the "Ares Z" for now. It is less than twice as expensive to fly the same rocket twice.

So, this "Ares Z" could easily lift Altair. The EDS weighs more than the Altair and more than the "Ares Z" can bring to a stable LEO, but if the EDS acts as its own second stage, then it could be lifted into LEO through burning itself after the "Ares Z" is expended. (Something like this was at one point considered for Ares V, but with the EDS being a partial third stage, not a partial second stage.)

The EDS launch with the "Ares Z" would be like an Ares V launch without Altair, except it uses already-developed four-segment SRB and the cheaper 8.4-meter core.


Anyways, it seems to me to be a good idea to only use the CEV/Dragon/$Favoritecapsule as a way to get humans through the atmosphere safely. That way, you don't have to manrate anything new, besides the upgraded heatshield. The Orion capsule would just attach to the rest of the stack (and probably stay in orbit, too). Heck, you could probably use a Soyuz if you had to. The design would ideally be modular, so that a cargo-variant Altair could be launched by itself and tugged to lunar orbit by an ion-propulsion craft, perhaps like VASIMR, in the future, or so that you could substitute a different crew capsule for Orion in case Orion is cancelled.

[gospacex]

Well, an Ares V without a second stage and only the four-segment solid rocket boasters (plus four or five RS 68s, of course) could put roughly 50+ tons in low earth orbit. Generally, in rocketry, the second stage costs at least as much as the first, and the four-segment SRB are already developed, so this should be much cheaper to both develop and fly than the Ares V. And you could use the much cheaper 8.4 meter diameter first stage, which will (theoretically) reduce development time and cost because it uses the same diameter as the shuttle's ET. I will call this the "Ares Z" for now.

You just reinvented the Jupiter-120.

[William Barton]

To me, the main point of a so-call 2.5-launch architecture has to center on the fact that we need some relatively inexpensive and reliable way to lug crews to LEO. Even if we still had a standard-issue Saturn V available, you still  wouldn't use one to ship crews to ISS (unless you had no other choice). So you develop something sized to ride up on the largest available off the shelf LV and capitalize it (i.e., its budget justification is) as a LEO vehicle. Then you have to capitalize the HLLV as the most bang for the least bucks, and you want the shortest path to whatever it is, from off the shelf hardware. It *seems* like that's Jupiter 120 (i.e., a hybrid of Shuttle and Delta IV hardware), though I'd be willing to entertain downstream EELV evolutions as well, if someone could show me how that would be cheaper (I already believe it would be technically better).

[Robotbeat]

To me, the main point of a so-call 2.5-launch architecture has to center on the fact that we need some relatively inexpensive and reliable way to lug crews to LEO. Even if we still had a standard-issue Saturn V available, you still  wouldn't use one to ship crews to ISS (unless you had no other choice). So you develop something sized to ride up on the largest available off the shelf LV and capitalize it (i.e., its budget justification is) as a LEO vehicle. Then you have to capitalize the HLLV as the most bang for the least bucks, and you want the shortest path to whatever it is, from off the shelf hardware. It *seems* like that's Jupiter 120 (i.e., a hybrid of Shuttle and Delta IV hardware), though I'd be willing to entertain downstream EELV evolutions as well, if someone could show me how that would be cheaper (I already believe it would be technically better).

That's exactly why you would do a 2.5 (or even a 1.5) launch architecture. See, right now, it seems like there's a big possibility (I'd say almost 50%, even if it is scaled back to only 4 segment first stage or something along those lines) that Ares I launches. It's not like there's only one way to build a rocket that works. Granted, a Jupiter 120 may be better than an Ares I, but the Ares I will probably have to be used for crew, since it's likely going to be available first. I guess I'm proposing a Jupiter 120 with more engines (a Jupiter 130/140?). And, we just use it for cargo launches (large fairing payloads and lunar/martian launches, mainly), and using it twice for a lunar launch. Besides, I think that lunar cargo missions would only need one Jupiter 130/140, since they can go much slower, taking advantage of lower energy transfer and possibly an ion drive.

Honestly, though, the Jupiter system makes sense.

[kraisee]

Wow.   I never even had to comment...   You guys have done it all for me

One thing I will say though, is that the propellant load for the TLI burn should not be underestimated.   Tankmodeler suggested a load in the region of 80mT, but that isn't going to be enough.

To perform the TLI burn from the intended 120x120nmi, 29deg orbit Constellation is using requires a burn of 3,175m/s.   With a standard 1% on top of that, you're now talking 3,206.75m/s.

You need to push an Orion which is capable of getting itself home at the end of the mission.   That's currently expected to mass 20,185kg at TLI.

Then you've got the Altair which is currently defined as a 45mT lander, with 5mT of additional management margins, grossing 50mT (used to be 9mT margins/54mT Gross Altair, which is still what we use for DIRECT).

Then you have the Cradle the Altair sits upon, often included as part of the "Airborne Support Equipment" or ASE.   That's currently expected to be 890kg.

Now you've got the mass of the EDS itself.   For current Ares-V's the burnout mass of that stage is around 22,396kg.   DIRECT's Jupiter Upper Stage is a completely different design, and masses around 28,525kg.

So, together the 'hardware' going through TLI masses around 93,471kg (Ares) to 99,600kg.


To perform a 3,206.75m/s ideal dV burn with 448s vac Isp J-2X's, that's going to require Ares-V provide an *absolute minimum* of 100,470kg of usable TLI propellant after loitering in orbit for 4 days.



This is why I have such a problem with NASA's Ares architecture in this regard.   The Ares-V has to lift that 100.5mT of propellant, plus extra to cover boiloff (1.4mT DIRECT, 3.3mT Ares), plus the 50.9mT of LSAM hardware.   You do the math and tell me how much payload the Ares-V is being forced to carry?   I make it 154.7mT must be lifted after regular 90% launch margins have been accounted for.   But NASA measures this without those margins; so using their methodology, we're actually talking about Ares-V has to be able to lift no less than 171.9mT or this architecture will fail to close its performance targets.

The old ESAS CaLV launcher had ~128mT of performance, so that was never going to cut it for this architecture.   The current LV 51.00.48 5.5-seg/6-engine behemoth can still only lift about 145mT -- by my estimate, NASA is currently still ~27mT short of meeting their targets with these Ares vehicles.

Griffin complained that DIRECT "breaks the laws of physics"...   Well I've got news for them regarding Ares.

Ross.

[robertross]

Wow.   I never even had to comment...   You guys have done it all for me

...

Griffin complained that DIRECT "breaks the laws of physics"...   Well I've got news for them regarding Ares.

Ross.

Isn't that a great feeling??? You're training & motivational speaking to us all is paying off.
I only hope that the new administration can see things just as clearly.

[kraisee]

Actually, no Robert.   It's one of the saddest feelings I've ever felt.

I have so much enthusiasm, admiration and encouragement for NASA as an agency and for >99% of the people involved in this amazing program.

But it has truly shaken me to the core to watch the current leadership drive their crazy "pet-project" into the wall the way they have done.   I feel for the dedicated guys and girls working feverishly to try to make this pig fly, knowing they'd like a different project, but always being denied the option.

I hope that things will finally begin to change for the better as soon as Griffin leaves in the New Year.

I just pray that it isn't already too late to save the VSE.   IMHO, Griffin has caused enormous problems and massive embarrassment to the agency, so much so that I wouldn't be in the slightest bit surprised if the new Administration doesn't just scale back the whole effort to LEO again and forgets the Exploration mission.

I think that is the #1 predicament facing us today and over the next few weeks.   But, I know of at least one well-researched plan which can get us out of this mess and off to the stars.   62 NASA engineers, 6 others and myself are quite literally working our butts off to try to offer a path out of this mess.

Wish us luck.   We need it.

Ross.

[robertross]

Actually, no Robert.   It's one of the saddest feelings I've ever felt.

I have so much enthusiasm, admiration and encouragement for NASA as an agency and for >99% of the people involved in this amazing program.

But it has truly shaken me to the core to watch the current leadership drive their crazy "pet-project" into the wall the way they have done.   I feel for the dedicated guys and girls working feverishly to try to make this pig fly, knowing they'd like a different project, but always being denied the option.

I hope that things will finally begin to change for the better as soon as Griffin leaves in the New Year.

I just pray that it isn't already too late to save the VSE.   IMHO, Griffin has caused enormous problems and massive embarrassment to the agency, so much so that I wouldn't be in the slightest bit surprised if the new Administration doesn't just scale back the whole effort to LEO again and forgets the Exploration mission.

I think that is the #1 predicament facing us today and over the next few weeks.   But, I know of at least one well-researched plan which can get us out of this mess and off to the stars.   62 NASA engineers, 6 others and myself are quite literally working our butts off to try to offer a path out of this mess.

Wish us luck.   We need it.

Ross.

Well I think you and your team have earned alot of respect from fellow posters to this site, me especially. We all wish your team all the luck we can give you.

I can't stand BS and pig-headedness, for which you talk about and we can see and hear plainly from the postings & nonsense going on. I have to face that at work quite a bit lately, and it drives me up the wall and down the other side. Too much "I" and not enough "We" going on.


Don't get too down. You're on the right track with Direct. It's a new administration now. Let's hope they make the right call....

"auto-sequence start, and booster ignition of the Direct launch vehicle"

[kraisee]

We're still 'up'    We have a solution which we believe in and for which we have a lot of quiet internal NASA support for too.   That's cause for a lot of enthusiasm around here.

We're optimistic, but cautiously so.

Ross.