Major changes of NASA's exploration plans

najab · May 8, 2005

What's annoying is a thread being dragged off topic. Threads which have been irretrieveably dragged off topic get locked.

SpaceKiwi · May 8, 2005

.... and najaB introduces the thread to the M.A.D. principle. <img src="/images/icons/wink.gif" /> I have just read that Griffin wants to speed up development of the CEV in part to save some bucks, and consequently some threatened NASA programs, due to budgetry constraints. However, the general consensus seems to be that speeding development requires more cash, not less. Curious ..... <div class="Discussion_UserSignature"> Who is this superhero? Henry, the mild-mannered janitor ... could be!-------------------------------------------------------------------------------------------Bring Back The Black! </div>

drwayne · May 9, 2005

Cost elements at the "selling phase" should be considered particularly dubious. Wayne <div class="Discussion_UserSignature"> "1) Give no quarter; 2) Take no prisoners; 3) Sink everything." Admiral Jackie Fisher </div>

spacefire · May 9, 2005

why can't the ISS be left as is, supplied by Progres and crewed by the Soyuz, Shuttle canned and funds diverted to the CEV? A big budget canl get things moving really fast. <div class="Discussion_UserSignature"> http://asteroid-invasion.blogspot.comhttp://www.solvengineer.com/asteroid-invasion.html </div>

radarredux · May 9, 2005

> why can't the ISS be left as is, supplied by Progres and crewed by the Soyuz/i> (1) Just maintaining ISS takes 2-2.5 people, so there isn't a lot of science being done right now. To do some science, they need to expand the number of people. (2) There is that "obligation" thing to the international partners, but Griffin seems less supportive of this. (3) I don't think the Progress / Soyuz can bring up all the supplies that are required (e.g., I don't think they can haul up a new gyroscope). (4) The current agreement with Russia ends next year, so there are doubts whether US astronauts can get to and stay on the ISS without the shuttle. For example, the current escape requires a Soyuz, but without an agreement with Russia the US might not be able get in the Soyuz. Thus, the US could not keep an astronaut on the ISS because of no escape plan. Although, I actually agree with your sentiment. Fly the minimum number of shuttle missions to make ISS operationally complete (I have read this can be done in 8 flights). Then divert the funds to the CEV and a shuttle-derived HLV. Then when those come online, use the new HLV to launch additional pieces to the ISS.

SpaceKiwi · May 10, 2005

Yeah, I agree Doc, it's just the apparent contradiction that I find disconcerting. Griffin has had a fair bit to say on a fair number of issues facing NASA. No good being a straight-shooter if his aim is off to begin with. If he wants to save some of the programs, threatened by cancellation because of the new vision for space exploration, then the trade-off is that he can't spend up a storm on the CEV in a reduced number of years. Maybe he intends to offset increased spending on the CEV build phase by chopping some of the steps out of the CEV tendering and development phases, but it seems like he might have riled up Steidle with that idea. Smart is good, but I hope he doesn't think or believe he has the final answer to every problem needing confronting. I liked the 'fly-off' idea, and it seemed to work well for the F-22. I dunno, I'm a little nervous about the 'week next Tuesday' approach he seems to be taking. <div class="Discussion_UserSignature"> Who is this superhero? Henry, the mild-mannered janitor ... could be!-------------------------------------------------------------------------------------------Bring Back The Black! </div>

gunsandrockets · May 10, 2005

"And on the other end of the scale, we need to look at what new development makes the most sense. The CEV, with all that I want it to do, in terms of its ability to service space station and, later, go to the Moon, cannot be easily assumed to weigh less than 30 metric tons - the weight of the Apollo Command and Service Module stack (leaving aside the Lunar Module). It is not reasonable to suppose that vehicle that needs to carry maybe twice that many crew on some Earth orbital missions or have some cargo for some minor cargo and consumables, and have other missions, will weigh much less than that. A mass of that order will be at least several metric tons. It is, in effect, a shuttle replacement. Well, we don't have a vehicle today which does that job. So, the question going forward is, OK. you're going to have to do something new to do that job. What is that new thing? Will that be derived from general components at the NASA end or will that be an EELV upgrade? AS far as I am concerned its all about the money." If that's how Griffin feels than the Grumman/Boeing minimalist Soyuz style CEV proposal is in big big trouble. The larger Lockheed CEV looks to more easily absorb all the jobs Griffin wants a CEV to do. No wonder Lockheed choose to go with a big PR splash about it's CEV while Boeing is staying very quiet.

mrmorris · May 10, 2005

"The larger Lockheed CEV looks to more easily absorb all the jobs Griffin wants a CEV to do. " Cool -- you've seen some diagrams that include dimensions? I haven't seen anything so far that shows the size of the Boeing/Grumman proposal vs. the size of the LockMart one. Do you have a link? No? Then how exactly have you reached this conclusion? "No wonder Lockheed choose to go with a big PR splash about it's CEV while Boeing is staying very quiet. " Well that or LockMart is well aware that their proposal bites bad enough that no one would bother stealing any elements of it. Might as well spread it all over the place and see if something comes up. Heck -- it works for manure, and the two share many common traits.

wvbraun · May 10, 2005

"Well that or LockMart is well aware that their proposal bites bad enough that no one would bother stealing any elements of it. Might as well spread it all over the place and see if something comes up. Heck -- it works for manure, and the two share many common traits." ROTFLMAO! Well said. I will be *very* surprised if Griffin allows ESMD to select Lockheed's proposal. No way!

gunsandrockets · May 11, 2005

" I haven't seen anything so far that shows the size of the Boeing/Grumman proposal vs. the size of the LockMart one." Really? How surprising. We know the NASA Spiral One key dimension requirements: 14 cubic meters living space, 20 tons mass, etc. The configurations of the two competing vehicles are pretty well known by now. We know that the Lockheed Spiral One CEV is a single module lifting body spacecraft. And we know that the Grumman Spiral One CEV is a three module Soyuz style spacecraft. Haven't you seen this thread? http://uplink.space.com/showflat.php?Cat=&Board=missions&Number=211215&page=&view=&sb=&o=&fpart=1&vc=1 The Lockheed CEV, as a single module, has lots of growth potential. It could easily carry double the number of people as a short duration LEO shuttle, just by adding more seats. Or carry double the number on long duration lunar flights by functioning in the role of a pure re-entry vehicle. I suppose multiple smaller Grumman CEV re-entry modules could serve in the stead of a single Lockheed CEV. Sort of the t/Space method of a flood of small capsules. But that doesn't seem to be the direction of Griffin's thinking with his talk of a massive CEV of more than 30 tons. [loud confident Lockheed vs quiet nervous Boeing] "Well that or LockMart is well aware that their proposal bites bad enough that no one would bother stealing any elements of it." Ah! So that's it! Boeing is just security conscious! After all they wouldn't want to leak the astounding abilities of the Soyuz design now would they? The Soyuz secret. I should have known.

nacnud · May 11, 2005

We don't know anything about the Boeing/Grumman proposal, the image I found was just a piece of artwork on their web site. Don't take that as indicative of the final concept.

mrmorris · May 11, 2005

"I suppose multiple smaller Grumman CEV re-entry modules could serve in the stead of a single Lockheed CEV." Which portion of "...you've seen some diagrams that include dimensions?" did you not understand? Shall I get you a definition of the term 'dimensions'? Without having actual numbers showing scale -- a technical graphic, even if verifiably the correct one (which as nacnud mentions both on that thread and here... is not the case) is of indeterminable size. If you can't determine the size of either of the two craft -- then you can't state that one is bigger than the other... period. "We know the NASA Spiral One key dimension requirements: 14 cubic meters living space, 20 tons mass, etc. The configurations of the two competing vehicles are pretty well known by now. We know that the Lockheed Spiral One CEV is a single module lifting body spacecraft. And we know that the Grumman Spiral One CEV is a three module Soyuz style spacecraft. " OK -- we don't *know* what the Boeing/Grumman design is, as noted above. However, let's use the NASA dimension requirements to make a (very) gross estimate. 20 tons (short ton, US) = 18,143 kg. Soyuz TMA mass (according to Astronautix) = 7,220 kg. So the Grumman 'Soyuz' should be about 250% of the mass of the Soyuz. As I noted on another of the CEV threads, the interior volume of a capsule scales up considerably faster than the mass. This plus the fact that most of the subsystems don't have to be scaled up for a larger craft (communications, avionics, displays & controls, etc.), means that the potential crew volume will be much more than 250% of the original -- likely closer to 400 or 500%. We'll use 350% just for fun -- seeing as it's all a guesstimate anyway without hard data. The Soyuz TMA has about 9 m3 of usable space, so 350% of that would be 31.5 m3 of sp

gunsandrockets · May 11, 2005

"We don't know anything about the Boeing/Grumman proposal, the image I found was just a piece of artwork on their web site. Don't take that as indicative of the final concept. " I didn't, I took it as confirmation of what I already suspected. Every document I've seen so far from Boeing or Grumman shows a three module configuration spacecraft, usually with solar power panels. And if that's the way the designers are thinking why wouldn't they take advantage of the Soyuz layout? It's a natural choice. Have you seen anything so far, anything at all that indicates Grumman will NOT go with a three module configuration?

gunsandrockets · May 15, 2005

link to interesting article http://www.newscientist.com/article.ns?id=dn7345 excerpt << Now, Griffin has implied the teams may have to go back to the drawing board. "The CEV, with all that I want it to do in terms of its ability to service the space station and, later, go to the Moon, cannot be easily assumed to weigh less than 30 tonnes - the weight of the Apollo Command and Service Module stack," he said at a breakfast meeting in Washington, DC, US, according to SpaceRef.com. Heavy lifting That 50% increase in weight "is a big change in the requirement", says Robert Melton, a professor of aerospace engineering at Pennsylvania State University, US. It is possible in the timescale, he says, "but it's going to cost more". And Griffin hinted that the overall design of the existing shuttle setup - involving two solid rocket boosters and a large fuel tank to form a “stack” that carries the shuttle into space - could be used to carry the CEV and associated hardware for a Moon base. These payloads could weigh up to 100 tonnes. "As NASA administrator, I already own a heavy lifter [in] the space shuttle stack," said Griffin. "I will not give that up lightly and in fact can't responsibly do so because…any other solution for getting 100 tonnes into orbit is going to be more expensive than efficiently utilising what we already own." Radical redesign That change could also prove a "nontrivial engineering challenge" for the proposal teams if they have already designed their vehicles to launch on top of a heavy-lift rocket, says physicist Andrew Case, acting director of the SubOrbital Institute, a US trade association promoting crewed rocket flights to the edge of space. Indeed, the Northrop Grumman team declined to discuss its proposal with New Scientist because it might have to radically redesign

crix · May 15, 2005

Gah! So Griffin wants to retire his 50 ton shroud (shuttle orbiter) and replace it with a 30 ton crew shroud that probably will have to be launched on a SDS (Shuttle-Derived-Shroud)? WTF!!

grooble · May 15, 2005

If you go the CXV route then you only have to put up the CEV once. CXV program - est 400 million Space only CEV dev cost - unknown launching CEV one time only - 200 million? Actual moon mission cost once system is in place, 50-100 million?

gunsandrockets · May 20, 2005

So much ground to cover. I think it's necessary to begin with a remedial tutorial on the NASA requirements for the CEV. More lessons to follow in additional posts. "Based on the POD architecture, a set of Initial Performance Parameters (IPPs) has been defined for the CEV. For purposes of this request for proposals, industry is expected to provide an initial concept for a CEV spacecraft that shall: 1) Have a total gross liftoff weight (GLOW) of less than 20 metric tons. 2) Provide an abort capability during all phases of flight. 3) Be 2-fault tolerant to hardware component failures within safety critical systems except where design to minimum risk is approved by NASA. 4) Integrate with the Launch Vehicle (LV) to achieve low earth orbit. 5) Integrate with the Earth Departure Stage (EDS) to achieve lunar orbit. 6) Integrate with the Lunar Surface Access Module to achieve lunar surface mission objectives. 7) Integrate with Ground Support Systems for launch processing and mission control. 8) Integrate with In Space Support Systems to support overall Constellation command, control, communication, and information requirements. 9) Be capable of orbital maneuvers and rendezvous/docking with other Constellation systems. 10) Be capable of return from lunar orbit to the earth surface without assistance from external Constellation elements. 11) Be capable of supporting human life from launch on the earth surface through mission complete on earth surface during a maximum CEV crewed mission duration of 16 days. 12) Abort capability independent of LV or EDS flight control. 13) Be capable of unmanned operations for test flight purposes during Spiral 1 efforts and during lunar surface activities for Spirals 2 and 3. 14) Minimizing ground processing interfaces while maintaining

gofer · May 20, 2005

I'd say if you can't fit your module into 20 metric tonnes you are doing something wrong. 20 tonnes is one heck of a weight and volume. The Apollo examples are irrelevant here, for example you can envision architecture where your modules are "tanked up" at a LEO or an L1 fuel depot. (remember the fuel is the majority of the mass)

mrmorris · May 20, 2005

"5) Integrate with the Earth Departure Stage (EDS) to achieve lunar orbit. ... 10) Be capable of return from lunar orbit to the earth surface without assistance from external Constellation elements. The short version ... e) TEI burn from LLO (which is about a delta vee of 1 km/s) " You're reading that a bit differently than I am. It's required to dock with the EDS to achieve Lunar Orbit, but you feel the EDS is then discarded before the burn to come back to Earth orbit? So the winning team is supposed to launch this honking big fuel tank and engine combo into orbit that's only used for a one-way trip? I don't think so. It is my opinion that's NASA's way of saying the CEV must be capable of atmospheric re-entry (i.e. no requirement that you switch to a different capsule/etc. for the landing).

gunsandrockets · May 21, 2005

"If you go the CXV route then you only have to put up the CEV once. " You know I always thought t/Space was going the right way for manned spaceflight, at least as far as cheap access to LEO.

gunsandrockets · May 21, 2005

"This crowd certainly does not need lessons. You need lesson in tact. " Ahem. Why do you assume my post was addressing "this crowd"? Did you note who I was replying to? Did you note the tact of the person I was replying to? I didn't come to the space.com forums to fight with people, I came to share my fascination with space exploration with like minded people, however I am a big believer in tit for tat. "Well, I hope that vehicle [CEV] is never built. What good will it do? It only carries four people for 16 days. With that you need two vehicles sitting up at the ISS for escape purposes, or one plus one Soyuz." If you will look over the requirements for the CEV, there is no requirement for docking to the ISS, or serving as a CRV for the ISS. The requirements for the CEV are very much for missions to the Moon, not the LEO missions the Space Shuttle does. The closest analog to the CEV is the Apollo CSM. "The Saturn V inserted almost 50 Metric tons to a lunar trajectory and that was enough for a short sojurn on the lunar surface. What is this lighter vehicle going to do?" The Apollo CSM was designed around the single-launch low-Lunar-orbit-rendevous mission architecture. Without the Saturn V this is impossible. Since the CEV uses the EELV, it is instead using low-Earth-orbit-rendevous mission architecture. If you look over the CEV requirements again the architecture should be obvious. "Put that on top of the Shuttle stack and go to the moon. " Yes that is possible, and yes Griffin has been hinting that will be his new direction compared to the current CEV requirements. However the development of a heavy lift launch vehicle, even the Shuttle C based on the existing Space Shuttle, will be a large project unto itself with all the costs and risks that go along with it. For myself, I would like to see the large army of Shuttle support people that is such a drag on NASA's resources finally done away

gunsandrockets · May 21, 2005

"It's required to dock with the EDS to achieve Lunar Orbit, but you feel the EDS is then discarded before the burn to come back to Earth orbit? So the winning team is supposed to launch this honking big fuel tank and engine combo into orbit that's only used for a one-way trip? I don't think so." How is that much different than for the Apollo CSM? Actually the delta vee requirements for the Constellation CEV are even more modest than for the Apollo CSM. The Apollo CSM/LM stack of 45 tonnes was launched towards the moon by the Saturn V third stage. The CSM then had to burn to brake the 45 tonne stack into low-Lunar-orbit. Then the CSM had to TEI burn for return to earth. Astronautix.com describes the delta vee of the CSM at 2.8 km/s. The biggest difference between the Apollo CSM and the Constellation CEV is the CSM is mostly fuel tank with a small crew compartment wheras the CEV is mostly crew compartment with a small fuel tank.

gunsandrockets · May 21, 2005

"Well apparently there are a lot of people around the world who have absolutely no clue just how much more utility is possible when you take capsule designs that were made in the 60's, scale up by 200-250%, and put 21st century technology into them." Lesson Two I find it much more usefull to assume the design teams are competent professionals who are trying their best to win the contract and the money and glory that accompany it. Assuming bad faith and incompetence is a game that doesn't get you anywhere usefull, but I can play that game too. How's this, Boeing bribed the Lockheed team to put forward a losing design! See how easy that is? And how pointless.

gunsandrockets · May 21, 2005

"Which portion of "...you've seen some diagrams that include dimensions?" did you not understand? Shall I get you a definition of the term 'dimensions'? Without having actual numbers showing scale -- a technical graphic, even if verifiably the correct one (which as nacnud mentions both on that thread and here... is not the case) is of indeterminable size. If you can't determine the size of either of the two craft -- then you can't state that one is bigger than the other... period. " Lesson Three It's usefull to assume both design teams will try for the lightest vehicle that will fit the minimum requirements of the CEV. Lighter means smaller and cheaper, not only for the CEV itself but also for all the various propulsion systems, from launch vehicles to deep space propulsion modules, that the winning contractor will also build for NASA. It's usefull to assume NASA will choose the cheaper of the two designs that meet the minimum requirements. Since the basic body forms of the CEV competitors are known, and since examples of those body forms (Soyuz and Kliper) are available, and since detailed numbers are available for those examples, we can scale those examples up or down to reasonably estimate the numbers for the CEV competitors. I can give you a reasonable estimate of the Lockheed CEV length and width just from the artwork in Popular Mechanics which describes the CM+MM+PS as 70 feet long. So the Lockheed CEV is 10 meters long and 6 meters wide. See how easy that is? I can't give an estimate yet for the overall dimensions of the Grumman CEV yet. But I will estimate the Grumman re-entry module has a habitable space of 8 cubic meters based on the Grumman artwork which shows (contrary to the Soyuz) an apparently larger re-entry module than the orbital module. These dimensions also nicely fit in with a re-entry module that could squeeze in six people (as opposed to only 4) with some minor redesign, and with an orbital mo

gunsandrockets · May 22, 2005

1207 I don't know why you are so fixated on making things personal. That's your problem. I considered replying to the more substantive criticisms you made of my reasoning, but then realized virtually all the responses would be merely repeating myself from something I have already posted in this thread. It's not worth the effort. If you couldn't be bothered to pay attention the first time, it's not my job to spoon feed you the information.

Major changes of NASA's exploration plans

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