crazy idea for launching things into orbit

[MrDudeMan]

ok, this may sound crazy, but i have been thinking about it for years (off and on)

instead of a shuttle or some other space craft burning tons of gas to take off, why dont we give it a push? would we be able to bore a hole in the ground large enough to fit the craft, then constuct towers with large cables high above ground to pull it up at high speed? we could use some sort of huge mechanism to create tension, connect the cables to the craft, release the tension, the craft goes flying up in the air (like a water balloon launcher essentially) and then kick in the engines to get into space? sorry, that was the longest run-on sentence ever.

i realize this is kind of stupid, but what do you think?


visual


edit: note the role of the dandelion...

 

[VictorLazlo]

NASA has been looking at a horizontal launcher that works like a rail gun or a bullet train. It accelerates the craft horizontally, and then shoots it off a ramp at the end, and the engines kick in.

http://www.cnn.com/2002/TECH/space/01/03/maglev.launches/index.html

 

[TGHI]

It's hard to say. You would have to hoist that shuttle awfully fast to escape the pull of earth's gravity. I think the next feasible idea would be a rail gun to fire a shuttle into orbit.

 

[MrDudeMan]

sweet

i have never read anything about that, so as far as i am concerned, this was my idea and they are using it! woohoo! :sun:

anyone know any details about such a project?

 

[Jeff7]

Originally posted by: VictorLazlo
NASA has been looking at a horizontal launcher that works like a rail gun or a bullet train. It accelerates the craft horizontally, and then shoots it off a ramp at the end, and the engines kick in.

http://www.cnn.com/2002/TECH/space/01/03/maglev.launches/index.html

Interesting coincidence - Enterprise had an episode where they launched a warp 2 test craft using a runway like that, with a ramp at the end. Maybe they just read the article at CNN too.

 

[MrDudeMan]

Originally posted by: Jeff7

Originally posted by: VictorLazlo
NASA has been looking at a horizontal launcher that works like a rail gun or a bullet train. It accelerates the craft horizontally, and then shoots it off a ramp at the end, and the engines kick in.

http://www.cnn.com/2002/TECH/space/01/03/maglev.launches/index.html

Interesting coincidence - Enterprise had an episode where they launched a warp 2 test craft using a runway like that, with a ramp at the end. Maybe they just read the article at CNN too.

holy linking skills batman! i fixed that mess of a link for you

 

[tranceport]

That would probably work pretty good. If we could get around the gravity issue.

 

[MrDudeMan]

Originally posted by: tranceport
That would probably work pretty good. If we could get around the gravity issue.

bah...

 

[buleyb]

Don't forget, getting people up there is an easier problem than getting people up there without killing them with G-forces in the process

I still think the 'space elevator' idea has the best chance, but the carbon nano-tube world needs to move faster for that to happen

 

[gsaldivar]

buleyb is right - the G-Forces alone would kill any human aboard. Think of how long it takes for a space shuttle or rocket to get just a single rocket-length off the ground.. 5-10 seconds - at least! In order for a land-based slingshot design to be effective, it would have to "hurl" the rocket much more quickly - and forcefully. I doubt that a rocket or shuttle constructed out of modern materials would be structurally able to withstand the force of such a launch.

:beer:

 

[Adul]

Originally posted by: gsaldivar
buleyb is right - the G-Forces alone would kill any human aboard. Think of how long it takes for a space shuttle or rocket to get just a single rocket-length off the ground.. 5-10 seconds - at least! In order for a land-based slingshot design to be effective, it would have to "hurl" the rocket much more quickly - and forcefully. I doubt that a rocket or shuttle constructed out of modern materials would be structurally able to withstand the force of such a launch.

:beer:

not to mention the humans inside

 

[dukeofhazard]

havent any of you guys heard of gerald bull and the iraqi supergun?

he made a 250m gun that would have a 'slow burn' propellant that would fire/ accelerate a satellite - read nuke in reality - into space, and the design was basically done when the iraqis whacked him for talking about the designs to colleagues too much.

you could basically fire something up the slope of a mountain for 200-500 metres of barelling and then rocket propell it on the last stage, you could keep the g-forces reasonable, but with SOC/ single chip designs more common its less risky than it was.

 

[NeoPTLD]

Even if it did work, the rate of acceleration needed to achieve the desirable velocity in such a practial distance would generate such a high acceleration. The people in the craft won't be able to take it.

 

[rimshaker]

Going vertical requries too much work, and dangerous.

Think more in terms of catapult (like aircraft carriers), except the runway in the shape of a huge catenary.

Makes more sense. The shortest distance between 2 points is a straight line.... but the 'fastest' way between 2 points is a catenary path. At some enormous speed at the end of the upward runway, i'm sure a vehicle could get really high up in the air before engines kick in.

 

[AbsolutDealage]

All of this has pretty much been covered in depth by the JPL over at NASA.

Check it out.

 

[Mingon]

Originally posted by: dukeofhazard
havent any of you guys heard of gerald bull and the iraqi supergun?

he made a 250m gun that would have a 'slow burn' propellant that would fire/ accelerate a satellite - read nuke in reality - into space, and the design was basically done when the iraqis whacked him for talking about the designs to colleagues too much.

you could basically fire something up the slope of a mountain for 200-500 metres of barelling and then rocket propell it on the last stage, you could keep the g-forces reasonable, but with SOC/ single chip designs more common its less risky than it was.

Heard of it, I used to do experiments inside of 1 section! their was 12 sections iirc, each of which was roughly 1 metre in diameter and approx 10 metres long. The reason it was cancelled was due to a change in government policy towards iraq, in fact the breach was designed by the UK MOD.

As for the rail gun, the americans provided lots of funding for UK research into the EM gun (its official name) and although its gone off the boil recently its still viable, if very expensive. The problem with the gun itself was that you could only get about 12 shots from it before the rail needed re machining due to bore wear on the copper/tufnol rails which made up the sidewalls.

 

[Calin]

The most important problem is the air resistance - to became a satellite, a object must have some 8+ km/s at ground level. At that speed, the atmosphere will burn the craft, or slow it down very fast.
Accelerating at 10g (100m/s^2) will take 80 seconds, and a distance of 320 kilometers. There are not many people capable to withstand a 10g acceleration...
The use of the rockets launched from high-flying planes (like B-52) is justified thru the fact that this way, most of the heavy atmoshere is left behind (below) - a 15 km "jumpstart" and some 800 km/h (let's say .25 km/s) at start are not a big deal considering the 200+ km and several km/s the satellite is to be flown. However, the atmospheric pressure at 15km is only 10% of the one at sea-level, so the opposing force is much smaller.
So this could very well work, but starting from a much higher altitude, not sea-level

Calin

 

[gsellis]

"The Moon is a Harsh Mistress" by Robert Heinlein. The railgun is covered there. I think I remember the best site being in Nepal with the 'muzzle' being at 20,000 feet plus (more sites to pick from ). Yep, it needs to be long.

 

[zephyrprime]

but the carbon nano-tube world needs to move faster for that to happen

Hey, just the last week they managed to make a long cable of the stuff. But it was mechanically weak. Oh well - just a little more research!

 

[buleyb]

Originally posted by: zephyrprime

but the carbon nano-tube world needs to move faster for that to happen

Hey, just the last week they managed to make a long cable of the stuff. But it was mechanically weak. Oh well - just a little more research!

links?

 

[VictorLazlo]

Originally posted by: Calin
The most important problem is the air resistance - to became a satellite, a object must have some 8+ km/s at ground level. At that speed, the atmosphere will burn the craft, or slow it down very fast.
Accelerating at 10g (100m/s^2) will take 80 seconds, and a distance of 320 kilometers. There are not many people capable to withstand a 10g acceleration...
The use of the rockets launched from high-flying planes (like B-52) is justified thru the fact that this way, most of the heavy atmoshere is left behind (below) - a 15 km "jumpstart" and some 800 km/h (let's say .25 km/s) at start are not a big deal considering the 200+ km and several km/s the satellite is to be flown. However, the atmospheric pressure at 15km is only 10% of the one at sea-level, so the opposing force is much smaller.
So this could very well work, but starting from a much higher altitude, not sea-level

Calin

Cut-and-paste from the JPL site:

Unlike the other gun concepts discussed above, the MagLifter concept seeks only to provide a small portion of the total Earth-to-orbit DeltaV; however, with its low acceleration (typically <3 gees), the MagLifter is able to use conventional (i.e., non-high-gee) stages and payloads and thus accrue a potential cost savings even with a low muzzle velocity.

 

[dkozloski]

Years ago the University of Montreal worked on a project where they used a 16" naval cannon mounted on railcars as a first stage to launch small spacecraft into orbit. They developed an inertial guidance system that would withstand the "G" forces involved as well as solid fuel rocket staging motors. There is nothing new under the sun.

 

[unipidity]

Not new, and highly impractical with the mechanism you described. Silly acceleration, silly material for the 'rubber band'.

Space elevators are a horrible horrible idea. Energetically unfavourable in comparison to a free method, only advantage is the use of more efficient propulsion.

 

[MrDudeMan]

Originally posted by: unipidity
Not new, and highly impractical with the mechanism you described. Silly acceleration, silly material for the 'rubber band'.

Space elevators are a horrible horrible idea. Energetically unfavourable in comparison to a free method, only advantage is the use of more efficient propulsion.

wow! very nice and unsupported flaming! who says its a fuggin rubber band? how about steel cables? hmmm??? less than 6 steel cables could easily support the weight of a shuttle and some rockets, so those breaking isnt even worth considering. silly acceleration? how is that possible exactly?? the airforce uses boosters to get cargo planes off the ground...how is this different? its a "boost." instead of wasting tons of rocket fuel, we could use solar energy to charge whatever mechanism would launch the shuttle, so our used energy would be basically free AND not spew tons of gas into the atmosphere. i fail to see how this is a bad idea.

now, for the simple minded wanna-be HT expert (thats you unipidty), you may interpret my diagram as how it should really be constructed. this is obviously just a sketch to get my idea across. the real thing would be way more complicated and more efficient. come back in here with at least an explanation and maybe you wont sound like such a turd.

 

[MrDudeMan]

Originally posted by: dkozloski
Years ago the University of Montreal worked on a project where they used a 16" naval cannon mounted on railcars as a first stage to launch small spacecraft into orbit. They developed an inertial guidance system that would withstand the "G" forces involved as well as solid fuel rocket staging motors. There is nothing new under the sun.

who said it was new? it was just something i thought of...