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In the last discussion we had. You're getting very close to troll territory my friend.

REPOST:

With all the talk lately about a space elevator, I got to thinking after recent slashdot discussion, just what advantages would a space elevator offer over a tower launch? I contacted the man responsible for a similar idea, the skyramp, (warning: hideous javascript menu may break firefox), Carlton Meyer, and had a dialogue in which he pointed me to the tower launch archive.

The ideas I see bandied about there are similar to what I had in mind, which would be essentially an 11km tall tower (think pylons rather than skyscrapers, based at sea), with evacuated airless launch tubes, using nuclear reactors to power a maglev or pulley system to accelerate vessels to escape velocity. These would then emerge above the end of the troposphere [gatech.edu], with it's associated weather and air pressure, and have little to no fuel needed to escape the earth's gravity, meaning you could do a lot more while you were up there. At normal launch accelerations you can get to LEO with very little external propulsion.

Not only would this enable multiple launches daily, it is, unlike the space elevator, readily achievable with today's technology, and financially viable as well. Given NASA had an annual budget of $16.2 billion for 2005 [space.com], and a nuclear power plant costs a cool billion to build, give or take, we could have this up and running in a few years.

Space has got vast, essentially unlimited resources. One recent story pointed out the trillion dollar iron asteroid up there. The thing has about 5 tons of steel for every man, woman and child on earth. And thats just one of god knows how many... billions more?

Once we leap the cost to escape hurdle (as I think I have managed), we can proceed to use these resources. There are several obstacles in the way of this, first of which is zero gee mining, we have no idea how to do it. We can either mine the ore out there, or bring the asteroid back into orbit and slice it up there. Or slice it up and send it back to orbit. I would be opposed to moving it back into orbit for processing, purely for the debris issue. Perhaps a lunar base would have some merit there.

So we set up a mining and processing operation either on the moon or in deep orbit, and start cutting and processing one of those bad boys. Whats the first thing we build? A bigger processing and mining operation. Space exploration, much like the internet, has to be a largely incestuous affair at first, existing solely for its own benefit.

Once we have that mastered, we can move to algae pods in orbit for food production, oxygen refining, and fuel production (biodiesel or chemical engines), all of which can be powered by the immense energy of the sun, and use the raw materials abundantly available in space. Whether you ship that stuff back to earth or use it for further colonisation, its a vital step.

The production of automated scouts is also a high priority; a vast amount of surveyor and prospector drones to sweep and map every square inch of every rock and gas in the system, out to the Oort cloud, and figure out what they are made of. I'd err on the side of quantity rather than quality, still no reason not to have either. This could be combined with deep space observatories that would make hubble look like the end of a coke bottle.

So now we have a manufacturing bridgehead, a good idea of what's interesting out there, and a cheap means to launch to orbit. Actual manned system ships would come next, to either colonise or investigate the system. The rest, as they say, is (future) history.

A lot of this would require automation, robotics, right up to the point when we build a larger manufactory from the orginal small one. Robots would als

Yet within the realm of science, we didn't have to advance much to get from one to the other. We needed an understanding of rocketry, some knowledge of life support, some advances in various engineering disciplines.

So you are telling me that the leap from canvas winged powered kites to putting men on the moon wasn't much of an advance?

Moreso in space since you've got to take into account the limitations imposed by automation, or else deal with the problems associated with long term space habitation and life support, and you've got to get from Earth orbit to wherever it is in the asteroid belt you're planning to mine/build

What limitations? I wasn't proposing an AI to drive them, more like remote piloting with certain systems semi autonomous. With that in mind there are no limitations on automation. And its a whole lot easier to get from earth orbit to wherever than it is to get from the earth's surface to wherever.

Have you checked the price of putting something in even LEO lately? We need to make serious improvements to our launch technology first if we're going to do anything like building stuff in the belt.

Heyyy, wow did you ask the wrong man. Here's an older post I made....

With all the talk lately about a space elevator, I got to thinking after a recent slashdot discussion, just what advantages would a space elevator offer over a tower launch? I contacted the man responsible for a similar idea, the skyramp (warning: hideous javascript menu may break firefox), Carlton Meyer, and had a dialogue in which he pointed me to a tower launch archive.

The ideas I see bandied about there are similar to what I had in mind, which would be essentially an 11km tall tower (think pylons rather than skyscrapers, based at sea), with evacuated airless launch tubes, using nuclear reactors to power a maglev or pulley system to accelerate vessels to escape velocity. These would then emerge above the end of the troposphere, with it's associated weather and air pressure, and have little to no fuel needed to escape the earth's gravity, meaning you could do a lot more while you were up there. At normal launch accelerations you can get to LEO with very little external propulsion.

Not only would this enable multiple launches daily, it is, unlike the space elevator, readily achievable with today's technology, and financially viable as well. Given NASA had an annual budget of $16.2 billion for 2005, and a nuclear power plant costs a cool billion to build, give or take, we could have this up and running in a few years.

Space has got vast, essentially unlimited resources. One recent story pointed out the trillion dollar iron asteroid up there. The thing has about 5 tons of steel for every man, woman and child on earth. And thats just one of god knows how many... billions more?

Once we leap the cost to escape hurdle (as I think I have managed), we can proceed to use these resources. There are several obstacles in the way of this, first of which is zero gee mining, we have no idea how to do it. We can either mine the ore out there, or bring the asteroid back into orbit and slice it up there. Or slice it up and send it back to orbit. I would be opposed to moving it back into orbit for processing, purely for the debris issue. Perhaps a lunar base would have some merit there.

So we set up a mining and processing operation either on the moon or in deep orbit, and start cutting and processing one of those bad boys. Whats the first thing we build? A bigger processing and mining operation. Space exploration, much like the internet, has to be a largely incestuous affair at first, existing solely for its own benef

There might be methods whereby you wouldn't need to carry the fuel with you, for example with a space elevator. However, just what advantages would a space elevator offer over a tower launch? (I've used parts of this post before, but I have since refined my ideas). I contacted a man responsible for a similar idea a while back, the skyramp (warning: hideous javascript menu may break firefox), Carlton Meyer, and had a dialogue in which he pointed me to a tower launch archive.

The ideas I see bandied about there are similar to what I had in mind, which would be essentially an 11km tall tower (think pylons rather than skyscrapers, based at sea), with evacuated airless launch tubes, using nuclear reactors to power a maglev or pulley system to accelerate vessels to escape velocity. These would then emerge above the end of the troposphere, with it's associated weather and air pressure, and have little to no fuel needed to match the earth's gravity, meaning you could do a lot more while you were up there. At a reasonable acceleration (5 to 7 g's) you would be in geostationary orbit. From there you could build a fully system wide ship or ships, as its much easier to escape the planet's gravity from GEO than from the surface.

Not only would this enable multiple launches daily, it is, unlike the space elevator, readily achievable with today's technology, and financially viable as well. Given NASA had an annual budget of $16.2 billion for 2005, and a nuclear power plant costs a cool billion to build, give or take, we could have this up and running in a few years.

I would like to ask your opinion of an idea I have... With all the talk lately about a space elevator, I got to thinking after a not so recent slashdot discussion, just what advantages would a space elevator offer over a tower launch? I contacted the man responsible for a similar idea, the skyramp (warning: hideous javascript menu may break firefox), Carlton Meyer, and had a dialogue in which he pointed me to a tower launch archive.

The ideas I see bandied about there are similar to what I had in mind, which would be essentially an 11km tall tower (think pylons rather than skyscrapers, based at sea), with evacuated airless launch tubes, using nuclear reactors to power a maglev or pulley system to accelerate vessels to escape velocity. These would then emerge above the end of the troposphere, with it's associated weather and air pressure, and have little to no fuel needed to reach GEO, meaning you could do a lot more while you were up there. I originally estimated reaching escape velocity with this system, but it turns out I got the numbers wrong and that would only be suitable for electronics and things that could withstand insane G-forces.

Not only would this enable multiple launches daily, it is, unlike the space elevator, readily achievable with today's technology, and financially viable as well. Consider the big dig in Boston has cost about 12 billion so far... Given NASA had an annual budget of $16.2 billion for 2005, and a nuclear power plant costs a cool billion to build, give or take, we could have this up and running in a few years.

Its not FTL but baby will it get the ball rolling. I'll just run this by everyone here... With all the talk lately about a space elevator, I got to thinking after a sort of recent slashdot discussion, just what advantages would a space elevator offer over a tower launch? I contacted the man responsible for a similar idea, the skyramp (warning: hideous javascript menu may break firefox), Carlton Meyer, and had a dialogue in which he pointed me to a tower launch archive.

The ideas I see bandied about there are similar to what I had in mind, which would be essentially an 11km tall tower (think pylons rather than skyscrapers, based at sea), with evacuated airless launch tubes, using nuclear reactors to power a maglev or pulley system to accelerate vessels to escape velocity. These would then emerge above the end of the troposphere, with it's associated weather and air pressure, and have little to no fuel needed to escape the earth's gravity, meaning you could do a lot more while you were up there. At 1m/s acceleration, you would be at escape velocity when you exit the top of the tower.

Not only would this enable multiple launches daily, it is, unlike the space elevator, readily achievable with today's technology, and financially viable as well. Given NASA had an annual budget of $16.2 billion for 2005, and a nuclear power plant costs a cool billion to build, give or take, we could have this up and running in a few years. And once we are up there...

Space has got vast, essentially unlimited resources. One recent story pointed out the trillion dollar iron asteroid up there. The thing has about 5 tons of steel for every man, woman and child on earth. And thats just one of god knows how many... billions more?

Once we leap the cost to escape hurdle (as I think I have managed), we can proceed to use these resources. There are several obstacles in the way of this, first of which is zero gee mining, we have no idea how to do it. We can either mine the ore out there, or bring the asteroid back into orbit and slice it up there. Or slice it up and send it back to orbit. I would be opposed to moving it back into orbit for processing, purely for the debris issue. Perhaps a lunar base would have some merit there.

So we set up a mining and processing operation either on the moon or in deep orbit, and start cutting and processing one of those bad boys. Whats the first thing we build? A bigger processing and mining operation. Space exploration, much like the internet, has to be a largely incestuous affair at first, existing solely for its own benefit.

Once we have that mastered, we can move to algae pods in orbit for food production, oxygen refining, and fuel production (biodiesel or chemical engines), all of which can be powered by the immense energy of the sun, and use the raw materials abundantly available in space. Whether you ship that stuff back to earth or use it for further colonisation, its a vital step.

The production of automated scouts is also a high priority; a vast amount of surveyor and prospector drones to sweep and map every square inch of every rock and gas in the system, out to the Oort cloud, and figure out what they are made of. I'd err on the side of quantity rather than quality, still no reason not to have either. This could be combined with deep space observatories that would make hubble look like the end of a coke bottle.

So now we have a manufacturing bridgehead, a good idea of what's interesting out there, and a cheap means to launch to orbit. Actual manned system ships would come next, to either colonise or investigate the system. The rest, as they say, is (future) history.

A lot of this would require automatio

I don't see any quotes from Von Braun. In fact, Von Braun thought the Saturn V was his baby for launches. Using accelerators to get up to speed in thick atmosphere is a very different idea that AFAIK, he never got behind.

About the closest thing they have is on this page where they take Von Braun's consultation for a movie as serious evidence that he backed such a scheme. That's not exactly evidence.

BTW, any site that uses Java Applets for each rollover button (something possible without Java) needs to be shot.

All these "carrier plane" based ideas make me barf, but the "new" launch vehicle nasa is coming out with makes me want to barf even more.

FFS Listen to what Von Braun said dammit

Read: http://www.skyramp.org/

I'm not vouching for the science behind the Sky Ramp, but it's similar to what you're proposing. The idea is to use a ramp and sled instead of a first stage. Beware: the website design is painful.

Here. Check out this link. Imagine the possibilities: long inclined launch ramp = low launch costs = pervasive human presence in space. Nuclear propulsion would be nice, too.

And I seriously wonder if the Indian aerospace industry is up to the task of building this thing. But if they are, then bully for them.

A pure ramjet first stage saves you a huge amount of fuel while greatly reducing the engineering requirements for the upper stages. Sled and catapult tech has been around forever that would get to mach 0.5 - 1 with large loads at moderate (2 -4 g) acceleration. Then you can get to about mach 2 - 3 at a substantial upward vector and 90- 120kft with fairly simple designs. The second stage then drops out the back (internal carriage greatly reduces boil-off of cryogenic fuel and has other positive effects such as reducing the needed strength of the 2nd stage - the nose has much less air to push through at the release altitude, and the 1st stage provides some lateral support as well). The first stage can then descend, slow and deploy parafoils for a glider landing at its home base. This strategy allows the first stage to be almost instantly reusable and to employ cheap, non cryogenic fuel. The first stage has extremely low drag, high top speed, low landing speed, low complexity, high manufaturability and with proper design can be made to allow a safe abort at any part of the flight.

http://www.skyramp.org/ has some interesting although not sufficiently technical stuff on catapults (for ramjet launch a horizontal design is fine)

http://mae.ucdavis.edu/faculty/sarigul/aiaa2001-46 19.pdf
Critically reviews many air launch proposals and provides an internal carrige on standard cargo plane method that allegedly solves the problems. (By their standards the 15% Skylon mass fraction (41 MT craft with a 275 MT takeoff weight) is unlikely, particularly in an SSTO craft with landing gear. Bond tends to overpromise, as the first two iterations of HOTOL show.)

There are a lot of other things that have been proposed that do not and will not work. SSTO does not work. To achieve the >93% fuel fraction the craft has to be fat, but to achieve low drag it has to be thin. Scramjets have been on the drawing boards for decades and the designs are too fussy, the fuel consumption too high, the start speeds are too high and the materials needed are too expensive and hard to work with.

Catapult/ramjet first stage with internal additional stage(s) is the most nearly optimal plan I have seen that does not depend on unobtanium, unproven technology or gazillion-dollar ground facilities.

Then, when the materials tech becomes practical, they build a space elevator on the very same site. Makes perfect sense; at that point, they have the name and a shitload of capital to make it happen. Taxpayers have spent enough on incremental baby steps and aerospace subsidies.

May dreams such as these take wing and I'd be happy just to watch: (link)

Check out the site. It's full of fascinating stuff.

Let's establish a bigger human presence in space. We need it in order to foster international cooperation and to reestablish the concept of a true frontier in the public consciousness. To make this happen takes new technology and a willingness to abandon the socialized aerospace companies, who build their rockets not to move things into space, but to make money at public expense.

I find their arguments convincing. It's an incremental step using existing technology, but it's a big one.

Particularly if you're using this to get there. From my admittedly layman-oriented perspective, skyramp technology is an economical alternative to conventioal vertical-launch behemouths from the aerospace companies, which is why it needs a private, non-subsidized backer like Bezos in order to be built.

We, as in those who aspire to see great leaps in space technology, have been going about this the wrong way for a very long time. Check the link. This whole vertical lauch with chemical rockets paradigm is lucrative for aerospace contractors, but a monstrous waste in light of what we know about basic physics.