There is a good video "somewhere" on this forum on using a hydrogen gun to launch propellent to orbit. The idea is to put the gun in the ocean.
Studying the various mountains, the ideal location for such a setup I've found, for safety, angle, length, height, latitude, etc is Mount Kinabalu in Malaysia.
You need an 8km dead straight track at 5g. Can you get that? You could tunnel in but then you have pressure waves in the tunnel, or you have to evacuate it.
Lets say it leaves at Mach 3. the energy imparted is 405KJ/kg. I suppose that's the same a 40km altitude balloon launch. Could be worth it. You need an 8km dead straight track at 5g. Can you get that? You could tunnel in but then you have pressure waves in the tunnel, or you have to evacuate it.Why rocket sledge compared to electro-magnetic?
Quote from: alexterrell on 04/10/2011 09:54 PMYou need an 8km dead straight track at 5g. Can you get that? You could tunnel in but then you have pressure waves in the tunnel, or you have to evacuate it.Up the side of mountain, and capable of carrying hundreds of tons if it's going to get a decent payload in orbit. This alone sounds like a multi-billion dollar construction project to me.Not only that, the OP plans to re-use the sled, so an equivalent braking zone will be needed somewhere...I don't see what the sled buys you really. A re-usable rocket stage that reaches the same velocity is well within reach, and done properly should only cost a modest multiple of fuel costs to operate. See DC-X, Kistler, and the general approach Armadillo and Masten are taking.
It's already built once. Just not on the right location. http://www.holloman.af.mil/library/factsheets/factsheet.asp?id=5924I do not know how much it costed though. If you find it please post.
It is easier to let a rocket sled slide back from the mountain than to recoup a stage from the ocean.
Edit: it is also easier when you do not need to make guidance software and electronics for a stage. Let the rail guide it.
For the modest velocity and altitude you are adding, there's no reason to drop the rocket in the ocean. Fly it back to the launch site and land it like this: [noembed][/noembed]
I have become so convinced that rail launch by means of rocket sled on a mountain slope is the way to go.