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Zubrin's book *Entering Space,* pages 28-30, tells a sad story: that three plans for the International Space Station were drawn up, the most capable and cheapest of which proposed building a Shuttle C and launching the space station 70 tonnes at a time. But this plan was rejected because (1) launching the station 16 tonnes at a time would keep the shuttle busy and thereby "justify" creating it, and (2) it enabled a modular approach that meant the Europeans and Canadians could be involved building their own modules. But the result was an immensely expensive space station. A shuttle C could have launched it in 1 or 2 flights and it would be finished, and we'd have a heavy lifter as well!
-- RobS
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We should have just launched most of it with the Shuttle C and added their few modules later. I bet shuttle C would still be a good idea today, particularly considering that most proposed HLV's (Ares, Magnum) are shuttle dirived anyways. They are already planning to maintain the facilities, and since prototypes have been built, and the engines, arguably the testiest part of a rocket, well proven, I say do it today. Having a HLV cannot be a bad thing.
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Thanks for the ShuttleC link, short but explicite. A clean, powerful concept, whitout much of extra work to do since most of it has been done with the shuttle already.
But to say the truth, I don't trust anymore the public space agencies, canadian, europeen, russian or sadly to say, the american NASA, for that kind of project.
At that point, it would be better for NASA to sale all its patents to construct the shuttle and the shuttle C to private american companies and keeps focusing on science or the ISS if this is what NASA wants. I think that anybody would be happy to be transported by a ShuttleC "Boing" to Mars and pay an arm for that. Anyway here is the fact: no need to study matter/antimatter space propulsion, it seemed that the shuttle C was all what was needed for a real ambitious space exploration program and it has been abandonned ????
I want a Shuttle C quickly !!!!!
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A HLV may get us into orbit, but chemical propulsion is hard pressed to get us anywhere else. A year in space should get us to Jupiter or Saturn, not half-way to Mars, and we don't need anti-mater to do that. To needlessly extend flightimes just to depend on chemical combustion is not the path to opening up the system to mankind.
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When it comes to Mars, I think that when we're at the colonization stage that we shouldn't want fast travel times. This doesn't mean we don't want advanced propulsion. I think we should be maximizing the number of people that can go instead of maximizing the speed. (this assumes that whatever advanced propulsion tech. has a high enough thrust).
I agree, though, that we need to go much faster than what chemical propulsion offers today when it comes to the outer planets.
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By having the energy to send a smaller mass at a high dV, the same engine can throw a far greater mass at a lower dV. A high Wsp/high Isp propulsion system would be invaluble, capible of both rapid travel for people and slow high payload trips for unmanned cargo flights. I think we should always mininize flight time as it exposes the crew to radiation.
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Of course nebob2, we need a better propulsion system once in orbit. Nuclear/plasma/ionic/hybrid, we discussed everything in the forums here. But first, the problem before everything, is to send big masses in low orbit. Think in terms of cost-efficiency. With ShuttleC you can send a 50 tons nuclear/plasma engine in space, whitout it, you need 2 or 3 regular shuttle missions which already cost more than the engine itself.
I am not an expert but I think, from what I've read in this forum, that an interplanetary engine has to be relatively heavy to propulse a class 100 tons spaceship, maybe 20 tons (?) but it is also relatively simple in design and so relatively cheap compared to the cost to send it in orbit. There is relatively few moving mechanic pieces in a nuclear reactor or a ionic engine, and the technology has been tested. The price of such a non chemical engine is probably not higher than the price of all the engines and pompes of a single space shuttle.
Regarding the time travel, well, I would not be afraid of a 3/4 months trip, but 6 months would be long yes. The "Boing" Mars space ship could offer different prices for the different Mars/Earth configuration. Those who cannot afford the fast trip when Mars is closer would just pay for a slower but cheaper travel.
Anyway, all this is science fiction as long as there is no real space colonisation program. We can only trust private initiative.
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If you want to talk about Shuttle-C, notice the design described in Astronautix includes just 2 main engines. I tried to do a calculation using 3 main engines (same as the current shuttle orbiter), the same helium tanks and OMS pods as the current shuttle orbiter, an expendable payload fairing based on the fairing from Titan IV (same size as the shuttle cargo bay), an ablative heat shield like that used for Apollo, and a parafoil like that developed for X-38. The reason for an ablative heat shield was to reduce cost to service the heat shield for a second launch by simply unbolting it and replacing it with a new one. The current shuttle orbiter costs a lot to maintain its reusable heat shield. Land with extendable skids like the X-38, but with shock absorbers. The only thing expended that is not expended with the current shuttle is the fairing. Recovery would be with a flat bed truck with a truck crane. Landing mass would be about 14.4 tonnes, so a medium truck with tandem rear axle is all you need. On landing, you might want to send the existing orbiter service truck to drain OMS propellant tanks.
This calculation is based on a total launch mass exactly equalling the current shuttle. The result increased cargo capacity to 104.7 tonnes to 185km orbit, or 91.9t to 407km @ 51.6? inclination.
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