Post central for information on CEV IV - Before thread #3 melts down

SpaceNut · 2005-10-05 09:03:49

Lower specific impulse?? Extensive re-man-rating testing?? GRIFFIN!
If this is the case, then why oh why aren't we just putting a pair of tried-and-tested J-2 engines on the thing??
...to keep Stennis open, of course
*sighs*

Agreed for Da stick, use Ssme's for the HLLV only.

Also do we know if the capsule return from moon stage equiped with methane engines or are they part of the upper stage?

ftlwright · 2005-10-05 11:42:23

I've got to call BS on most of what Grey is saying here. If after 50 years we do not know how to adapt SDV components to the new mission architecture at a reasonalble cost, we have no good reason to go back up in the first place. Certainly, we won't be holding this thing together with duct tape, but the operating regime for the new vision isn't significantly different either. I would be more concerned if they were trying to manrate the RD-170 with its 3g lateral staging kicks. Considering the SSMEs throws up 230,000lbs dump truck while thrusting OFF-AXIS, its difficult for me to be too concerned about adapting it to a new mission.

With respect to the lower Isp: eh. That's a given since it will have a lower chamber pressure and most likely a reduced expansion ratio. I would imagine this would lead to a reduced wear-and-tear on the engines, which would be beneficial if they plan on recovering them.

I just don't see Grey's concerns being all that extraordinary, especially when compared to the alternative. I'm more concerned with the political considerations and Griffen's need to cater to congressional constituencies. This challenge is more daunting than any technical issues they may face.

SpaceNut · 2005-10-05 12:00:13

With respect to the lower Isp: eh. That's a given since it will have a lower chamber pressure and most likely a reduced expansion ratio. I would imagine this would lead to a reduced wear-and-tear on the engines, which would be beneficial if they plan on recovering them.

The flow of fuel to the chamber has not changed so the ISP will go up since the pressure on the outside has gone down.

GCNRevenger · 2005-10-05 13:27:11

I don't think that there will be a big problem with making the SRB itself capable of lifting the CEV and its upper stage, but this talk about the SSME is making me a might... testy.

The thing can already run in a vacuum, it does every time Shuttle flies, so what exactly is there to be done? The nozzle nor the chaimber nor the pumps should have to be changed much, it already runs quite well in a vacuum with the highest Isp for a large Hydrogen engine ever, so the biggest change is changing the startup sequence, right?

Why would the Isp be lower, it really doesn't make any sense, not unless the SSME has to be modified for higher thrust or something.

Griffin is walking a fine line, if he strays but a little, the credibility of his plan will disintegrate.

SpaceNut · 2005-10-05 14:03:17

I agree GCNRevenger "Griffin is walking a fine line, if he strays but a little, the credibility of his plan will disintegrate."

I would think that with all the stuff on hand that you could even build a prototype of the unit and never skip a beat on shuttles running to the ISS build scheduel when they begin flying again next year.

The upper stage should not be all that hard. We know that it is going to be 5.5 meters across and the abort launch tower has already been demo'ed a while back.

So design the capsules insides and lets go already.

Could we use the Delta 4 medium Delta RS-68 first stage without the gem 60 solids. The core is about the right size and the engine preformance is :
Thrust (vac): 337,807 kgf. Isp: 420 sec. Burn time: 249 sec. Isp(sl): 365 sec.

while the ssme is:
Thrust(vac): 232,301 kgf.
Thrust(vac): 2,278.00 kN. Isp: 453 sec. Isp (sea level): 363 sec. Burn time: 480 sec.

They look very simular in stats.

What do you think?

John Creighton · 2005-10-05 14:26:18

I don't find the article [URL=http://space.com/businesstechnology/technology/051005_nasa_details.html]NASA's Lunar Vision: The Devil's in the Details [URL] well thought out. Well some or many of the concerns addressed in the article may be legitimate if NASA can't handle these minor engineering hurtles then it has no business being in the business. The architecture proposed by Mr Grifin is about as affordable and low risk as you can get. It will accomplish much more then Apollo at half the cost and stays with NASA's allowed budget for space exploration. I agree the devil is in the details as with any plan but the article is clearly lacking any useful insight.

GCNRevenger · 2005-10-05 16:11:55

I agree GCNRevenger "Griffin is walking a fine line, if he strays but a little, the credibility of his plan will disintegrate."
I would think that with all the stuff on hand that you could even build a prototype of the unit and never skip a beat on shuttles running to the ISS build scheduel when they begin flying again next year.
The upper stage should not be all that hard. We know that it is going to be 5.5 meters across and the abort launch tower has already been demo'ed a while back.
So design the capsules insides and lets go already.
Could we use the Delta 4 medium Delta RS-68 first stage without the gem 60 solids. The core is about the right size and the engine preformance is :
Thrust (vac): 337,807 kgf. Isp: 420 sec. Burn time: 249 sec. Isp(sl): 365 sec.
while the ssme is:
Thrust(vac): 232,301 kgf.
Thrust(vac): 2,278.00 kN. Isp: 453 sec. Isp (sea level): 363 sec. Burn time: 480 sec.
They look very simular in stats.
What do you think?

Too much thrust, not enough Isp, and has no restart at all nor is in any way man rated or related to an engine that is.

The article got one thing right though, that NASA still hasn't explained WHY we need to go back, not even making any noise about the science. Where is the renders of a Lunar observatory? The predicted supply-versus-demand for Platinum? Something, anything!

Commodore · 2005-10-05 17:05:55

I really don't think they've planned that far ahead. Nowhere do they mention platnium, He3, metals, fuels of either the solid or liquid persassion.

Its obvious that they don't want to scare anyone with long term pricetags. But the media will do that regardless. The only way to counter that to do a phased approach that were we have something really spectacular at the end that requires a set number of affordable bite sized steps. They don't have that yet.

We have to make the first phase look easy. Cause it should be. Were amking it much hard than it needs to be.

GCNRevenger · 2005-10-05 19:56:55

For most government development projects or vauge science initiatives I would agree Commodore, but not this time.

NASA is having an increasingly difficult time justifying its exsistance (and its cost) and its credibility is all but spent, so NASA needs something more tangible and convincing (and apolitical) besides "Bush says so."

Remember how senators have been talking about VSE, its the "Bush Mars plan" this and "Presidents' Moon plan" that: this is not a good situation, and NASA could really use a more solid return on the investment besides low-priority space geology and technology development (which won't be much if they use available tech).

If NASA came forward tomorrow with a clear justification, even just coming right out and saying that long term Lunar astronomy & prospecting, Martian life sciences & colonization tech, and the economic bennefit of technology & inspiration are worth spending half what we did on Apollo per-year then they would be better off. Right now this "return to the Moon to, um, uh..." threatens to clip NASA's wings. Something besides vauge "space science!"

Commodore · 2005-10-05 20:58:00

We don't need justification for a manned space flight. A bare bones program is garenteed by the mere fact that the Russians and Chinese are doing it. That and Congress is not going to let their consitients and campaign contributors go hungery. A CEV, SRB Stick, and maybe a EELV ISS resupply module are a given.

The issue is rather were going to do something more productive. And I agree that what NASA has produced thus far as far a "master plan" for the Moon simply isn't enough in both objectives department and the engineering to support it.

Really, we aught to be thinking something up for the whole of VSE. The next 50 years. Because it will take a combination of resources from both the Moon, Mars, and NEO's to make everything work.

Austin Stanley · 2005-10-06 02:33:48

Grey's story reminds me of a passage in Macbeth, "A tale told by an idiot, full of sound and fury, signifying nothing."

He talks alot but it all basicly comes down to this. Some (not necessary alot) redesign and testing are necessary before the Stick can go forward.

Well duh.

Who would have thought that some design and testing would be necessary in the creation of a new manned space vehicle. The objects he raises are trivial and minor. But I mean if NASA managed to pull of the construction of the Shuttle and what not in the first place, I bet they can manage the trivial adaptations.

SpaceNut · 2005-10-06 11:25:17

Lots of possible uses for the HLV:
The Mega-Module Path To Space Exploration Or: How To Use An HLV

These include gas stations in space, Getting more hardware to orbit if fuel is waiting and more...

Commodore · 2005-10-06 18:09:29

Fantastic article right there. Especially if you consider those very same fuel modules can be modified with airlocks, launched empty and used as solid habs like Skylab. One or two and you'd have the volume of the ISS and then some.

On Orbit Fuel Storage modules would also solve all the problems of trying to exploit the tremendous volume of the ET by turning it into HAB, because they would also have it too. Although it still leaves the issue of unexploited volume, and the wasted 33tons of aluminum. Though the ETs would still be useful if launch un-insinuated like in the first couple shuttle missions (to prevent debris) and if they could be stored in orbit and shaded to prevent expansion and contraction. They would make lunar base building a whole lot faster if empty tanks could just be buried. You’re not just going to dump tons of regolith on a fancier module. As for getting them there, we are already going to have restart able SSME's from the Stick, so we can get them to orbit on residual fuels. Once there, they will need to be "shaded". Solar panels could be oriented to do it. In fact this might be a good spot to test the Solar Power Satellite concept, since your going to have lots of shaded space behind it. In any event, since it would be impractical to launch a tank with its own TLI stage on top of whatever cargo its hauling, they are going to have to be rounded up in LEO and sent together. We can attach the required landing gear here as well. Attach 6 or so together in hexagonal pattern on a pair of big gear shaped scaffolds. Finally, launch a final stack that mounts directly within the others. This would be the ideal position to mount landing legs and retro rockets from, because your cargo would all be fore of the tanks. Then it’s a relatively simple matter of deploying the payload faring, and unfolding legs down on predestinated tracks, once at the appropriate point, twist and wrap around the tank. Nose deorbiting thrusters can just pop out the sides of your cargo module. Fuel stored in the cargo module can send whole thing on its merry way. Of course its likely we could only this once we have the rovers on the ground to dig the trenches and bury them, unless we want to store them at L1, or at a polar site in the early years. I bet we could produce one bundle per year between everything we launch. And that more than enough volume for a big base. If we produce several bundles over the early scouting phases, we almost have more volume than we know what to do with. Later on we can launch all the furnishings well ahead, with the tanks coming a few months later, and basically build an entire base in 6-6 launches, not including manned launches.

Fuel depots are a whole issue by themselves. Its going to take a lot of rovers scooping up dirt 24/7 to create enough oxygen to make a fuel depot really work for us especially when combined with the shortage of hydrogen. I think your going to need an alternative source. Asteroids are the most obvious source, be are not easy to exploit. If you could a find a small (around 50m diameter) hydrogen and carbon rich one and get it in a highly elliptical lunar orbit, and then slow it down at the right time, you might be able to bring it down without making a mess. That would probably provide all for all your fuel needs for decades to come.

SpaceNut · 2005-10-07 08:57:20

Many of the same thoughts in this article.

The Mega-Module Path to Space Exploration (Or: How to Use an HLV)

SpaceNut · 2005-10-13 06:20:03

I find it interesting that senators are trying to get the construction of DaStick to there own respective states.

[url=http://www.flatoday.com/apps/pbcs.dll/article?AID=/20051013/NEWS02/510130346/1007]Senator promotes KSC assembly site

Nelson plans meetings to tout the advantages[/url]

Sen. Bill Nelson is trying to help broker a deal to make Brevard County the final assembly site for the spaceship proposed to replace NASA's shuttles and carry Americans back to the moon.
Nelson, D-Melbourne, said preliminary studies show that assembling the new ships near the Kennedy Space Center launch site could save cash-strapped NASA at least $400 million annually and protect as many as 500 local space jobs that might otherwise be lost when the shuttles retire in 2010.

Does He realize that they are only launching maybe 2 a year at most just to save this small amount.

Grypd · 2005-10-13 08:30:48

Northrop Grumman-Boeing show there concept for the CEV.

Northrop Grumman-Boeing space systems press release

The CEV that they have devised will though only slightly larger than the Apollo module will be able to hold double the crew in this case 6 instead of Apollos 3. This will be done by the use of advanced materials and it will still be safer with the addition of two seperate safety systems.

redhorizons · 2005-10-13 09:24:22

I just now got around to reading Zubrin's comments on NASA's plan, posted here
http://www.marssociety.org/news/2005/1001.asp, and I had a couple thoughts.

1) Since there is going to be such a crunch to insure that we launch the CEV soon after the HLV gets the lunar mod into orbit, why not take a little different approach.
The way it is set up now we have to wait for the right conditions to lauch, and the weather at KSC is often erratic and there always seems to be a reason to delay launch. Instead of using the proposed launch system why not use something like Peagusus, where you can get the CEV above the weather and then launch?
2) Why the hell are we still flying the shuttle. I could think of a lot of things I could with $30bil over the next few years.

SpaceNut · 2005-10-13 10:42:52

Another cause for concern is the decision to launch the CEV after the HLV that delivers the rest of the mission components to orbit. The HLV’s cargo will include stages employing cryogenic liquid hydrogen/oxygen propellant, and this propellant will start to boil away immediately after launch. Thus for the mission to succeed, the CEV must be launched on time, within a few weeks at most of the prior flight, without fail.

This sticking point of seperate is easily solved, a little research did yield that we have 2 launch crawler units. Now whether they are both operative is a better question?

Crawler - Transporter

publiusr · 2005-10-13 11:13:38

I think some of the HLLV bashers are just playing plitics--hoping for SDV to die, when the EELVs Esp Delta IV is winding up a worse pad sitter than Titan IV.

http://en.wikipedia.org/wiki/Shuttle_De … ch_Vehicle
http://www.thespacereview.com/article/462/1
http://forum.nasaspaceflight.com/forums … ts=7#M6426 HLLV

Misc. From The web:
"You can watch a few pictures of the first zero-G fight of Kliper at
http://spacemodels.nuxit.net/Kliper/zerog/index.htm. This is a 1/50
model built by Serge Gracieux which flew last month in the Novespace
Zero-G Airbus 300."

by Vincent Meens

http://spacemodels.nuxit.net/
http://en.wikipedia.org/wiki/Kliper

http://forum.nasaspaceflight.com/forums … 32&posts=6 ESA

More news on the Russian front:
http://www.nasaspaceflight.com/ ANGARA pad done

The ABMA would be sad
http://www.spacedaily.com/news/spaceport-05l.html

CEV

http://images.spaceref.com/news/2005/nas.esas.17.l.jpg
The Beatles song "Get Back" comes to mind! More on the ESAS here:
http://www.spaceref.com/news/viewnews.html?id=1069
http://www.spaceref.com/news/viewnews.html?id=1069

Interorbital
http://www.spacedaily.com/news/spacetravel-05zzzs.html

Buran launch
http://www.northstarrocketry.org.uk/junk/Buran1.wmv

GCNRevenger · 2005-10-13 13:07:57

hey Publiusr, think you might be a little more... compact with your use of blank space to seperate blocks of irrelivent links? Thanks.

Commodore:

I am very much against the fuel depot nonsense, at least in the shorter term. Until there is a supply of Lunar LOX, then reuseability of Lunar vehicles won't be very practical. Reuseability is the only practical use for a space fuel depot, because you already need an HLLV worth of fuel to put any signifigant (20MT+) payloads or crews on the Moon. They don't make any sense.

The tanks themselves weigh so much, that placing them into LUNAR orbit would require far too much fuel. Best cast senario, the EDS stage being designed for VSE could only push one or two spent first stages to Lunar orbit. Thas to say nothing of the second EDS-sized stage you would need to get them to the surface. Why don't you purpose-build the much thicker and more puncture resistant TransHAB modules and send them with those rockets instead?

redhorizons:

Beware of whatever Bob says, because everything (without a single noteworthy exception) he says is designed to further the cause of getting humans to Mars in the shortest possible amount of time. Even if they can't accomplish anything useful or run an unacceptable risk of death in the process... and even if what he says isn't true. He told several bald-faced and factually incorrect - which even a sharp highschooler could have pointed out - lies about O'Keefes' EELV-based Lunar arcitecture. He hated it, enough to use colorful language like "The previous NASA plans were pure bullshit," to describe it... because it wasn't HLLV centric, and you need an HLLV to get to Mars.

I believe that Zubrin wants a smaller, lighter capsule because it would limit what we could do on the Moon (thus reducing our investment there) and in the likly event the capsule is used for Earth return from a Mars mission, would also reduce the scope of such a mission... which would speed it up, even though we would get lots less productivity for our money.

If he is worried about the CEV mating to the EDS/LSAM for Lunar missions, we will have been flying the CEV for some time by this point, so we should be pretty good at making it fly by then.

As far as the ISS goes however, I do agree with him, that there is no good reason for us to bother with it beyond the political consequences of abandoning the project. I don't agree however that we should use SDV vehicles to finish the station, since the station modules or the SDV itself would require too much modification or Moon/Mars-hurting design compromises. Oh, and Hubble should not be repaired either.

SpaceNut · 2005-10-14 06:02:44

Peviously I mentioned the lobbying to get DaStick built in KSC but since then I have found that other locations would want to do the same.
[url=http://www2.dailynews.com/antelopevalley/ci_3114050]Antelope Valley leaders seeking space jobs
Next manned craft prompts local effort[/url]

Among those signing the letter were Rep. Howard "Buck" McKeon, R-Santa Clarita, whose district includes Air Force Plant 42 in Palmdale - a potential work site for the program. Also signing the letter was Rep. Bill Thomas, R-Bakersfield, whose district includes Edwards Air Force Base - a potential landing site for the spacecraft.
Although NASA narrowed the field of competitors down to two teams in June, the agency's formal call for proposals from the teams won't come until probably mid-November. NASA is looking to select one team in 2006 to build the craft.
Once state officials get a better handle on what the contractors need, they will approach local entities to let them know what will be required to get involved in seeking work. The officials will also have an idea as to state legislation that might be required, Daniels said.
In Florida, a similar team has been set up to help make that state more competitive for work on the program.
Florida advocates argue that building the crew exploration vehicle in their state makes sense because it will avoid transportation time and costs in shipping it to the Kennedy Space Center. It would also avoid duplication of effort in having the spaceship built by one team and then having a Florida team conduct the final preparation for launch.

So let me see if I have this right, it is cheaper to send the SRB's segments from Utah to KSC than to this other site in CA. Sounds like fuzzy math time to me..

It would appear that no matter which team wins the contact it will be up to them to get it to the launch site to be intergrated togther for launch since the pieces will be from multiple sites it would seem.

This is going to come down to who can build it for less if the designs end up being comparable from either team.

SpaceNut · 2005-10-17 10:51:18

Northrop Grumman/Boeing Team Unveils CEV Design

cost estimates for the design, government and industry sources have said NASA’s CEV is expected to cost $5.5 billion to develop and the Crew Launch Vehicle another $3.2 billion. Flight testing is expected to add another $2 billion to $3 billion to the price tag.
NASA has budgeted $1.8 billion for the CEV and Crew Launch Vehicle design effort for 2006.

Gee what about the savings from cancelled flights of shuttle in 2004,2005...

SpaceNut · 2005-10-18 09:09:53

[url=http://www.orlandosentinel.com/news/custom/space/orl-spaceship1805oct18,0,2327398.story?coll=orl-news-headlines-space]Aerospace giants vie for prize

Northrop Grumman and Boeing compete with Lockheed Martin to build NASA's next manned spaceship.[/url]

NASA will issue its final instructions to the competitors at the end of this month, spokesman J.D. Harrington said. The space agency wants to go back to a capsule system similar to the one under the Apollo program that first took astronauts to the moon.
Each team will have 90 days to tweak its proposal, and then NASA will have 90 days to pick the winner, which is expected to happen next spring.

Plan mode of use:

NASA has been exceptionally specific about what it wants for the vehicle that will replace the space shuttle.
The CEV would launch on a solid rocket booster originally designed for the shuttle fleet and carry six astronauts on trips to the international space station. Eventually, that same vehicle would take four astronauts on the longer trip to lunar orbit.
It would be shaped like a capsule -- unlike the winged shuttle -- and would parachute back to Earth.
For trips to the moon, it would rendezvous in space with a cargo rocket carrying the propulsion system that would then take it out of Earth orbit, as well as the lunar landing module that would carry astronauts to the moon's surface

Supposed cost to develop:

It's expected to cost $105 billion to get the moon-Mars program up and running. Sources said the CEV portion -- which is the first step -- will cost about $5 billion to develop.

All to be used, when?:

The Crew Exploration Vehicle is supposed to take astronauts to the international space station by 2012, to the moon by 2018 and eventually to Mars. It likely will be the only manned vehicle for getting to and from space that NASA builds for a generation.

GCNRevenger · 2005-10-18 09:38:08

Thats an awful lot of money for test flights... probobly has to do with paying the Shuttle Army to do basically nothing while the smaller CEV/Stick crews do their thing and before the big HLLV program gets going?

If its not, and we're assuming say half a dozen flights, that puts each shot at ~$300M... thats pretty high, alot of that money has to be going someplace where its not needed or shared with some other expense.

SpaceNut · 2005-10-21 10:37:05

This noted on Nasawatch:

CEV Selection Delayed
Editor's note: Contractors were told today by NASA that the CEV selection is being delayed - until late Spring/early summer 2006 - most likely June. Stay tuned.

Probably more than a rumor given the fact that the huricane season has hurt Nasa manufacturing in regards to both Lockheed and Boeings for shuttle hardware.

New Mars Forums

Announcement

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