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I can't help but wonder whether we might just be able to assemble the Paris VII in the Vab. At this point I think it just depends on the maximum height (although remember the payload shroud could be attached outside of the hab) and width of the biggest door. Perhaps the VAB height could be extended, and bigger doors cut out, without too much fuss. The Paris VII would then be transported on a tower-less MLP, as it will be self-supporting. The only obstacle then is a much (much) more heavy duty pad cooling system.

Honestly, when I first put these designs out there, they were only meant to provoke thought. I did not expect they would be realistic. However, you can see the numbers have turned out more accomodatable than I had previously imagined. We could build this thing tomorrow, if we really had to.

Mwahahaha! I shall take over the world! 

Yeah, I got the height, but I can't find the width. All the pics I can find show same door as the lower photo, but I can't figure what the top photo shows. Is there a bigger door around the back or something?

To understand where I've got the payload figures from, let's compare Paris III with the Delta IV Heavy:

Delta IV Heavy Core Stage = 5.1m diameter x 40.8 m height = ~ 834 cubic meters volume.

Paris III Core Stage = 10m diameter x 100m height = 7857 cubic meters.

Considering the increased performance from propellant cross-feed, better tank mass efficiencies (bigger tanks), and the presumably higher ISP of future RS-68's, we could round this up to 10 times the Delta IV Heavy payload?

Damn, thats only ~270 tonnes. Oh well, that'll have to do.

Edit: My original estimates were made from this chart: http://www.boeing.com/defense-space/spa … ptions.pdf
From the chart I can guess 700 tonnes for the Paris VII is not too unreasonable, due to the increased staging.

Yeah I know. What can ya do? 

Nevertheless, If we really needed a 300T booster, it can be seen that Paris III isn't terribly less efficient than current designs. Thought provokingly, it will still be significantly cheaper than the Shuttle, cost per pound. Although I concede that the one-time cost of developing the necessary support infrastructure might not be worth it.

Also, I'd imagine Paris III to come around 2030, after the moon has been explored with Ares V's and VII's. A mars mission will (finally) be on the cards then, and the current apollo-era support infrastructure will be starting to crumble. Also, something better and cheaper than the RS-68 might have popped up by then. Perhaps more significantly though, the US economy will be bigger.

BTW, if Paris III costs 2 billion, then Paris VII would cost 2*(7/3) = 4.7 billion. Although the cost per pound will be the same. Paris VII might be a good basis for a quick and dirty mega-booster, in the event of a killer asteroid prevention mission.

Could the Ares-V main tank use a common bulkhead to save weight?

Exactly. Conceivably, the greatest leap in development costs will be from 4 to 5 segments. If thats the case, we might get more bang for buck if we jump to 6 instead; forgetting the 5-segment SRB altogether.

Of course, this is assuming a 6-segment SRB can be designed without requiring a prohibitively expensive redesign of any component (e.g. a clean-sheet nozzle) over the 5-seg. In the end, if the current 5-segment CLV is proved to underperform, then a 6-segment may be exactly what NASA needs anyway.

If it wasn't for 'The Stick', you'd be right. And you may still be right yet. They may be unnecessary, but the development of 5-segment SRB's are an opportunity.  If that be the case, perhaps they should be up-scaled to 6-segments before work has begun?

As it is today, with a 10m tank and RS-68's, I personally think Ares-VII is about the biggest you could go without requiring a prohibitively large step up in development costs.

While I like the way you think, gaetanomarano, you do seem a little biased against the current plan. Perhaps I can persuade you by attempting to sum up some of the considerations to be made when contemplating future HLV's:

1. 5-segment SRB's have been part of Thiokols plans for some time. Most importantly, I think NASA seems them as necessary for the development of the Ares I. Because this is the case, they may as well be used for the Ares-V aswell. In this case, the increased thrust from the 5-seg SRB's will require re-design of attachment points, and reinforcement of that section of tank.Unless 'The Stick' is scrubbed (which is not completely unlikely), I imagine 5-seg SRB's are inevitable.

2. Going with an inline launch configuration will require reinforcement down the whole length of tank, to support the weight of the upper stage and payload.

These first two points already start to make a case for a clean-sheet main tank. However, it is the third point which is the final nail in the coffin:

3. Switching to RS-68 engines requires more tank volume to achieve the same payload. Therefore, a larger tank diameter is required if the vehicle is not to be unduly high.

I believe all three points have worked together to justify the current Ares V design.

However, if we're going to invest so much in re-design, we should not limit the potential of the end product. Personally, I would like to see NASA over-design their new main tank to allow for future additions, infrastructure permitting. That should include 3 or 4-SRB configurations, and extended tank lengths. Also, I'm not convinced that the step from an 8.4 to only 10m diameter is justified. Apollo-era tooling will have to be atleast re-built. Perhaps it would be convient to scale the tooling aswell. I'd imagine 12m or more would be favorable; I'm not sure where the limit exists.

As you can see, this is quite a lot of work. I can definately see where your coming from. But from my point of view, you can squander your pennies and get something whcih doesn't quite meet your needs, or you can spend big and get exactly what you want. Whether NASA's eyes are too big their wallet, I don't know.

They don't? Why not?

I've been away from newmars for about a year, so forgive me if this sort of thing has been discussed in any length before. Actually, this would be a good place to post info on 3 and 4 SRB Ares-V derived vehicle configurations. Just now I've found gaetanomarano's page suggesting a 3 4-segment SDV would be quicker route to a 120+ tonne heavy lift capability. http://www.gaetanomarano.it/articles/006_superSLV.html.

However, now that the Ares development plan is in full steam, its seems fully shuttle-derived vehicles are out of favor, however unfortunate that may be.