Rocket production-based CATS

[Crossover_Maniac]

In the race of cheap access to space, new technology and alternatives to rockets have be proposed. SSTO, scramjets, maglev, skyhooks, etc. But there has been some work being done on cutting the cost of conventional launch vehicles such as the EELV. But more radical approaches as been proposed. The BDB (Big Dumb Booster) in which a rocket would be constructed with less emphasis on performance and more on cutting cost. Steel instead of space age alloys, pressure-fed rockets instead of turbopumps, and hybrids over liquid or solid as ways to cutting the cost by avoiding unnecessary complexity and expense for the sake of performance. Two other projects come to mind: Otrag and Aquarius.

Otrag is a launch vehicle composed entirely of parallel-staged rockets stacked side-by-side. It runs contrary to rules of rocket design which states to keep the parallel staging to a minimum and to avoid it altogether in order to minimum drag. However, the Otrag disregards this rule for the sake of mass-production. The parallel stages are identical, which means they can be mass-produced. One type of rocket nozzle, one type of tank, one type of structure, etc. While the added drag means less payload per launch, the overall mission cost is cut with the streamlined production.

Aquarius is the ultimate expendable vehicle. Aquarius cuts cost at the expense of increasing its chance of failure. Most rockets have a 95-99% rate of success. Aquarius will only have an estimated success rate of 67% or two launches out of three or at least it's design that way. Rather than improving the design to minimize a scrubbed launch, Aquarius will only do enough to get some of their rockets up. This would not work with multi-million dollar sats or astronauts as the payload. Instead, Aquarius' payload will be cheap expendables such as food, water, fuel, and air. The logic behind this reasoning valid. It makes little sense to spend millions on improving the reliability of a launch vehicle for cargo that is only worth a few thousand at the most when it's cheaper to launch rocket not quite reliable and just taking a loss. The team that has designed Aquarius is betting that it is more cost effective to lose more launch vehicles and launch another load of cheap cargo on another rocket than it is to spend R & D money to improve reliability.

My opinion is that more work should be done, at least when it comes to bulk expendable cargo as a means to reduce the overall cost of going into space. What do you think?

 

[scottb50]

My opinion is that more work should be done, at least when it comes to bulk expendable cargo as a means to reduce the overall cost of going into space. What do you think?

I still think the best approach is a TSTO, totally re-usable fly back first stage with an upper stage that is dismantled and used to add to or build stations and vehicles in LEO. Upper stage engines would be used for power in and beyond LEO or returned for launch re-use as cargo. I would favor a medium lift and heavy lift version of the first stage and various upper stage configurations to match payload needs.

 

[tampaDreamer]

Ortag sounds like SpaceX's approach with the mass produced smaller rockets being combined.

 

[Stewie_Griffin]

Ortag sounds like SpaceX's approach with the mass produced smaller rockets being combined.

I'll have to disagree.

SpaceX's approach has been the same as other major companies such as Boeing and Orbital Sciences. The only different thing about SpaceX is their focus on reusability.

So technically their approach is the opposite approach used for Otrag.

Anyway I agree with Crossover_maniac, mass production of simple, expendable launch vehicles is the best way of bringing costs down. Complex, reusable, SSTO's are not the answer!

 

[frodo1008]

The entire EELV concept is based upon low cost production. The Common Booster Core of both the Delta IV and the Atlas V are designed around a standard booster, powered by a standard Engine (either the RS68, by Pratt and Whitney Rocketdyne for the Delta IV. Or the Atlas V which uses the Russian RD-180 engine, along with the Atlas V Common Booster Core.

So the issue of such production to be used by this Otrag system has already been addressed. In fact, it is even more heavily addressed in the Heavy versions of these systems, each of which uses three such systems to be able to launch some 50,000 lbs to LEO.

The problem for CATS is NOT this type of production capability, it is the number of launches that such a system can take advantage of. The more launches, the lower the cost with such a system.

However, at this time there just aren't that many launches.

Heck, if a private concern wanted to use the space shuttle to place some four 12,000 lb (48,000 lbs total, which is well within the total capability of the space shuttle orbiter bay). for the current launch cost of some $500 million, which would mean a launch cost to LEO of $125 million for each satellite (just about the current launch costs), such a system would be feasible! But nobody is currently launching anywhere near that many satellites!

In fact one of the things that troubles me about the upcoming retirement of the space shuttle, is why doesn't NASA at least try and find somebody that might try to make such private a use of such a system? They could even then provide a service to launch all the people and the materials up to the ISS (and also bring materials and people back) at a cost at least as good as the Russians are now quoting NASA for the use of the far less capable Soyuz!

Heck, if NASA would be worried about somebody with too little experience servicing and launching the space shuttle, why not just give them to ULA (which has been servicing and launching the shuttles all along anyway), and purchase such services form ULA! Each of the remaining shuttles has more then 50 flights left in its capability, and therefore would last far longer then the ISS anyway! How is that for thinking outside of the box?

Then, if you include the competition of such as ESA, Japan, Russia, China, and soon to be India and Brazil, the launch market begins to become very, very crowded!!

Sooooo, we have a kind of Catch 22, chicken or the egg kind of thing going here. Until you get the launch costs down, you supposedly are not going to be launching that much stuff up to LEO. However, one of the best methods of reducing the individual launch costs is to be launching that much more stuff!!

 

[scottb50]

Heck, if NASA would be worried about somebody with too little experience servicing and launching the space shuttle, why not just give them to ULA (which has been servicing and launching the shuttles all along anyway), and purchase such services form ULA! Each of the remaining shuttles has more then 50 flights left in its capability, and therefore would last far longer then the ISS anyway! How is that for thinking outside of the box?

Then, if you include the competition of such as ESA, Japan, Russia, China, and soon to be India and Brazil, the launch market begins to become very, very crowded!!

Sooooo, we have a kind of Catch 22, chicken or the egg kind of thing going here. Until you get the launch costs down, you supposedly are not going to be launching that much stuff up to LEO. However, one of the best methods of reducing the individual launch costs is to be launching that much more stuff!![/quote]

I think it's more the problem is the Shuttle just isn't safe enough and was never evolved beyond the original design to be turned into a commercial vehicle. That the basic concept could not be evolved is another story, the idea cheap re-usable, repairable and reconfigured in place satellites could be developed seems like a good concept. Further would be larger Platforms that could allow plug-in sensors, cameras, transmitters and receivers or other devices, that could be switched out as needed or added to as demand requires.

The basic idea behind the Shuttle is still valid, that it was never able to fill that need doesn't mean the need doesn't exist. That NASA really doesn't have to meet the need for commercial uses, just their own needs for research and exploration, the ARES makes sense. As a commercial launcher it couldn't compete with Delta or Atlas and Orion would do the same thing Soyus does, but would be uneconomical for commercial uses.