I was watching the HISTORY Channel last night-they had a fascinating show on about the early Russian space program-it stirred my memory. Many yeras ago, I remember reading about NASA trying to build a nuclear-powered rocket engine. It was called the “KIWI”, and they got as far as building a prototype. It was mounted on a railroad car, and got as far as a test firing. Apparently, something went wrong, as the program was abandoned by the mid=1960’s.
Does anybody know the fate of this program, and was there any real chance of building a nuclear powered rocket engine?
I don’t know.
There was an interesting program on Orion recently (basically, blow up nuclear devices just behind your spaceship that then push on the spaceship). It included some great footage of the scale model tests they did (with conventional explosives). There were cerainly some environmental problems with using Orion in or near the Earth’s atmosphere.
I don’t know much about this, but I do know the concept was not similar to the “Orion” design JonF describes.
If you’re talking about what I think you’re talking about, you’re talking about Nuclear Thermal Rockets or NTRs. These work just like regular rockets: the fuel is a reaction mass that is thrown out the back end of the rocket at a high rate of speed.
They don’t use explosions of any kind. Rather, the nuclear pile heats up the reaction mass to make it much hotter and more energetic than a conventional rocket, so it’s thrown out the back end at a VERY high rate of speed, thus providing much greater thrust.
I don’t know why NASA scrapped the project, but given the unfortunate success of the anti-nuclear movement in the US it’s pretty easy to guess.
Kiwi was the reactor that would have been included in the Nerva rocket family, a classic political football that limped along through increasingly restrictive budget cuts throughout the 1960’s:
…Apollo research and development funding declined from $2.9 billion in FY 1967 to $2 billion in FY 1969. Initially, NASA’s follow-on programs to Apollo-Skylab, an earth orbital laboratory; Voyager, an unmanned Mars mission; and Nerva, a nuclear rocket engine - bore the brunt of the cutbacks. Funding for space programs to follow Apollo appeared in the Johnson administration’s 1968 budget. Congress sharply reduced Nerva and Apollo Applications (Skylab) appropriations, cutting the latter from $454.7 million to $253 million. Voyager was eliminated entirely, while Apollo funds fell by less than 2%. For FY 1969 the Johnson administration budgeted $439.6 million for Apollo Applications, $38 million for 1971 and 1973 unmanned missions to Mars, and $41 million for Nerva. Again all three programs were cut sharply…
From http://www.hq.nasa.gov/office/pao/History/Timeline/1961-4.html
It was Nixon, I believe, who officially killed it, but the Vietnam War is what was bleeding away the funding.
Interestingly, despite the obvious opposition the entire world would have to a nuclear reactor floating around over their heads, the Nerva project refuses to die a quiet death, and is constantly being revived. Here’s a list of proposed nuclear rockets in the Nerva family as well as a DARPA project or two:
So, um, the moral of the story is, if you happen to see a pathetic mixed metaphor like a limping political football, please do the right thing and kill it before it gets posted.
See also Weapons that Did Not Make the Cut - describes project PLUTO (nuclear ramjet powered cruise missile) and Project Orion.