Posted on 09/23/2005 2:45:56 PM PDT by tricky_k_1972
For all those interested on why projects like X-33, Venturestar or any other SSTO (Single stage to Orbit) eventually fail in today's world without the use of Nuclear power from an engineering standpoint, I will direct you here:
The Cold Equations Of Spaceflight
The Freeper discusion on the topic:
I've been dreaming to see this for YEARS now.
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The main obstacles to nuclear propulsion seem to be political rather than technical.
We all have.
I agree, unfortunately the political obstacles are formidable.
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The last time I visited the "What's next?" exhibit at the Smithsonian's Air and Space Museum, I left angry. The exhibit starts with all sorts of promising technology including NERVA that's been mothballed for decades because "nuclear" became a bad word near the end I found a little Mars exhibit that asked something like, "Should we disturb the prisine environment of Mars with mankind's presence?" Where next? According to that exhibit, the dark ages.
Or they could just build it in secret at groom lake then announce it later.
1000 ton payloads make a big interplantary craft in a hurry.
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The guy that wrote this also figured out that you can use it for nuclear waste disposal, so not only is it environmentally "clean" and reusable, it also cleans the environment as it works.
The problem is we're still talking vertical takeoff with 100% of the required fuel and oxidizer from ground level. I know you're promoting nuclear, but that's never going to happen politically.
By using air for oxidizer for roughly half the acceleration, you drastically reduce the required weight for oxidizer, and thus reduce the fuel required and the size of the vehicle that must carry it, thus saving even more fuel. The savings snowball.
Aerodynamic lift up to 100k feet is far more efficient than vertical takeoff, saving even more fuel, and allowing smaller engines.
Taking off with only partial fuel, and tanking via garden variety Air Force tanker allows takeoff with even smaller engines than lifting the whole thing from a runway. An SR-71 can't even get off the runway with full fuel, and I'm sure a runway to orbit vehicle would not either.
The months required, if not years, for building/refurbishing very large rockets will run the cost up just as it did the Shuttle, which originally was supposed to have turn around times measured in weeks.
Yes, we need high lift unmanned rockets to get large components into space, at least until we can fabricate them on the moon, mars, or asteroids (which will be a long time from now). But human transport and resupply should be via some kind of Turbo/Ram/Scram/Rocket aircraft. Yes the development cost would be extraordinarily high. But until we build such a thing that can be re-flown within a day of landing, or less, then space flight will be only dreams and fodder for government pork.
No thanks.
If I was President that is exactly what I would do, and damn the consequences, at least I could leave that much of a legacy for the American people and the world.
Chemical powered booster: really, really, expensive.
This is the reason why nuclear propulsion was discarded. There is unfortunately no compelling (economic) reason for manned space travel, and the specialized robotic missions that NASA and similar agencies mount each cost a lot more than the cost of the expendable boosters used launch them.
If we built such a thing, and sent humans to visit Mars and begin to colonize the Moon, I would be thrilled. But it isn't going to happen in our lifetime.
It's possible they already have one and we won't know about it until the political climate is friendly to it's existance. I would sure like to see the ChiComies faces when/if we ever unveil such a wonderful craft.
The president wants a bold new vision for future space travel, he should take advantage of the great american skunk works machine and make it happen. We don't have to know about it until it's a glowing success. (no pun intended)
Maybe a SpaceShip One / Nuke Rocket combo licensing would interest Mr Rutan if their were federal dollars wrapped in a black project just for him.
I love the proposed power source. Even if we can build a space elevator, perhaps the most efficient possible way to LEO, a power plant like this would improve getting around the solar system. If it can be made to work it surely creates better options for spaceflight. Much of the power plant testing could be done safely on ground. The main ground test limitation would be the effects of variable acceleration, from zero to a few G, on the plumbing of the thing.
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