Space Elevator, What the Hell? Options

[Demonseed Elite]

I gotta admit, I'm still stuck on where New York plays into a space elevator discussion.

[BishopMcQ]

As one of the writers working on the NYC Missions, I don't think I'm releasing any major secrets if I say that a space elevator has not been mentioned anywhere I could hear it. That rumor put to rest, I don't know why Frank chose New York to mention in the original post.

I gracefully bow to the advanced understanding of physics and engineering in the earlier posts and posit that they will be better capable of questioning how to build such an elevator. Personally, I would tend to say build the beanstalk (the first term I knew for a space elevator) near Nairobi--5,400 feet above sea level and close to the equator.

[Fix-it]

I would say don't build it at all, and make cheaper rockets, and better reuseables.

[GryMor]

I would say don't build it at all, and make cheaper rockets, and better reuseables.

Rockets are inherently inefficient due to requiring reaction mass and having to lift their energy generation. From a certain perspective, the elevator is the ultimate reusable space entry vehicle as you don't lift any of the fuel, you don't lose anything to wind resistance, you don't need to lift any atmospheric specific shielding, and most of the lift vehicles can be recycled in orbit and used for construction materials (why would you want to drop something down the well that you just spent energy lifting out of it), what with it being scaffolding, electric motors and a photo voltaic power receiver. Just keep a few for passenger traffic, but your doing something wrong if you are dropping even 1/10th of what your lifting via the elevator (asteroid mining changes that, except then you have slag that can be used for aero breaking heat shields, so you still don't need the vehicles to head back down the tether).

[Kyoto Kid]

Fact: A near-earth orbit asteroid is already being moved into local orbit by a Triple A consortium. (in Emergence).

...OK, now who hacked my firewall and downloaded my notes on the Olympus Group? 'Fess up... (IMG:style_emoticons/default/grinbig.gif)

[Fortune]

I believe Ancient History (or was it Synner?) mentioned that some of the technology is being produced in New York, or that the City plays some similar part in the venture.

[Drogos]

Personally, if I want to place a space elevator in NYC, I will because all hard science went out the window when Great Dragons took to the sky.

Of course, that's my games, and I worry more about setting and mood than hard science fiction...as for canon, they should probably make sure some hard science is represented, and it looks like they are. You can continue with your regularly scheduled technobabble. (IMG:style_emoticons/default/wink.gif)

[Particle_Beam]

Bah, who needs to build space elevators, if you can simply speed up Space Rockets with the Movement Power, so that they'll consume less fuel and need less time to go up there than with a dumb space elevator anyway? And best of all, they won't have any accidents on the way.

[Grinder]

Would you trust your very expensive rocket and its cargo a spirit?

[Particle_Beam]

Considering that it's under control of your loyal wagemage, sure. The same as you trust your very expensive rocket to the pilots, the maintenance crew, your guards and whatever. All rockets in SR are magically boosted with the Movement Power to be as fast as any object in contact with the Speedforce. Of course, so are ships and airplanes. Also, the spirit doesn't have to accompany the rocket physically. He just stays on Earth, while the rocket flies off till the upper gaiasphere, where the sustained spirit powers (which can be sustained beyond line of sight without any problems) break off, but by then, the rocket has already reached its destination point, and saved tons of fuel and time.

[Grinder]

But pilots, crew and all other people are that - people. (Meta)humans. And not an entity from another plane, more or less controlled by a mage. And we all know how fucked up mages can be. (IMG:style_emoticons/default/grinbig.gif)

[Particle_Beam]

So what? Corps trust them enough to pour buttloads of cash for providing magical safety, research, and other services. Heck, according to SR 3 Magic in the Shadows, Corps would rather shoot dead an Exec instead of losing a valuable mage, and I doubt this has changed in SR 4.

It's safe, it saves buttloads of money, time and fuel, and it's the most obvious way to enhance space travel (heck, every cargo transportation worldwide). Only inbreed chimpanzees who were born from donkey-feces wouldn't use spirits for something important like that. And seeing as how none of the corps are currently lead by inbreed chimpanzees born from donkey-poo, they use their (often times) human intellect to realize how powerful and useful Movement and other Spirit Powers are.

[Demonseed Elite]

I believe Ancient History (or was it Synner?) mentioned that some of the technology is being produced in New York, or that the City plays some similar part in the venture.

That might be possible. After all, Trans-Orbital has a powerful presence in New York as does Prometheus Engineering, a mysterious corporation involved in materials engineering (and rents research space on Ares' Apollo orbital).

[Grinder]

So what? Corps trust them enough to pour buttloads of cash for providing magical safety, research, and other services. Heck, according to SR 3 Magic in the Shadows, Corps would rather shoot dead an Exec instead of losing a valuable mage, and I doubt this has changed in SR 4.

Damn fine point.

It's safe, it saves buttloads of money, time and fuel, and it's the most obvious way to enhance space travel (heck, every cargo transportation worldwide). Only inbreed chimpanzees who were born from donkey-feces wouldn't use spirits for something important like that. And seeing as how none of the corps are currently lead by inbreed chimpanzees born from donkey-poo, they use their (often times) human intellect to realize how powerful and useful Movement and other Spirit Powers are.

Awesome! Colorful pictures enrich every posting. (IMG:style_emoticons/default/rotfl.gif)

But don't let us stray away too far from the topic. And there's a thread for the impact of spirits on the transportation business already.

[kigmatzomat]

The massive amount of energy {catapults} require isn't that much higher then that of a climber considering that you can ignore atmospheric friction after the first 100km.

The climber also ignores atmospheric friction after the first 100km so no big whoop.

One advantage the catapult has is it doesn't carry a motor. Although the size of the motors isn't really that big if you're willing to take many hours to reach orbit, although that increases the life support system for passenger travel.

One big disadvantage that catapults have is that they have to launch with significantly greater than escape velocity. Meaning if you need 11kps to reach orbit, you probably start with 15kps at ground level and have slowed to 11.1kps at the edge of the atmosphere.

The other massive disadvantage of catapults is the ratio of size of the catapult vs. launchable materials. A small catapult requires more acceleration. More acceleration will start damaging the cargo. Sustained forces of 9-12G will kill most people. Short-duration forces of 40G cause significant trauma to people and is probably risky to many objects. Heck, freeze dried food probably risks being turned to powder under any more force. So let's set the limit at 40G.
40G = 9.81m/s^2 = 392.4 m/s^2. To reach 11kps at 40G takes 28 seconds and requires a 150km catapult (or appropriate number of times around a loop). To hit an assumed 15kps at ground level is 38 seconds and 283km of catapult/loop travel.

For a passenger catapult, limited to 7G, you require 218 seconds and 1600km of loop/apult. And that catapult better be depressurized or you've got ~3.5 minutes of ground level sonic boom. Plus it provides a constant 7G of acceleration.

I'm not sure that's easier than a space elevator. I mean, the elevator can be hand waived away with one leap of material science. "Tada, Unbreakium!"

Speaking of massive construction when comparing anything but the death star to a space elevator is a bit weird and maintenance would also be ok considering your maintenance crew can reach their workplace by car and failure of a tether in a tether catapult also is way less dramatic then loosing the whole elevator to a cascade.

Tether catapult? Do you mean a space hook or sky hook? Where you've got a rock and a long rope with a hook spinning (vertically) at the same rotational velocity as the planet's surface so that the hook hits the ground at essentially zero velocity?

In some ways I like those more than elevators since there's around a 50% chance that nothing slams into the Earth, assuming your "rock" is set up to fragment into sufficiently small parts that it won't survive reeentry. Flip side, you've got a ginormous rope of Unbreakium winging through the atmosphere. The effect of a hurricane worries me.

[kigmatzomat]

Slight divergence here.

SR has, by canon, orbital power satellites. IIRC that's how Japan became a new global megapower.

If you have the ability to beam down megawatts of power, why not use a laser-pumped rocket? This setup involves firing an energy beam into a dense mass that sublimates into gas with a lot of expansion, hence generating thrust. (Think dry ice and a magnifying glass) The reaction is more endothermic than exothermic, meaning the propellant is not a fuel (won't burn or explode), doesn't need dangerous oxidizers or cryogenics, and may have a better specific impulse (thrust/mass propellant). You could beam the power at the rocket from top and/or bottom simultaneously.

I think many current systems are 2- or 3-stage lift vehicles. You could probably eliminate the first and third stage, with a conventional rocket only for the middle stage.

[Stahlseele]

i've seen a documentary about that once . .
problems with that system arise at the point where you have to keep the propelled rocket exactly above the laser, else it will crash to one side . . and of course, later on there is simply not enough athmosphere to burn to creathe the thrust . . also it would be very uncomfortable to travel in something that's basically getting a big kick into it's ass every some seconds or so . . with rockets you have an ongoing explosion, not many different ones and the vibrations of that are allready tremendous . .

[kzt]

Personally, I would tend to say build the beanstalk (the first term I knew for a space elevator) near Nairobi--5,400 feet above sea level and close to the equator.

Nah, Baker Island. 0°11.7′N 176°28.7′W 0°11.7′N 176°28.7′W.

[Kyoto Kid]

...I'll stick with slipstream injection lifting body craft and avoid the engineering migraine.

I keep thinking of the sitting duck an orbital lift system would be for eco-politico terrorists or some whacked out dragon from east of the Urals. (IMG:style_emoticons/default/grinbig.gif)

[Adarael]

Yeah. I have a hard time believing that would last more than a couple of weeks in Shadowrun's volitile political climate.

[Herald of Verjig...]

Yeah. I have a hard time believing that would last more than a couple of weeks in Shadowrun's volitile political climate.

Joint megacorp projects tend to be durable. Zurich hasn't been shot out of the sky, but there is no shortage of ICBMs and more specific surface to space missiles. The factions who would want to completely deny the corps the benefit of such a project are usually fairly small, while the ones interested in manipulating how much each corp benefits are much larger.

Another point, the orbiting end is stable with or without the cable, monowire is fairly easily mass produced in SR, and this is a very defended corp facility. If something happens, they drop another cable and use it to justify significant increases in the land holdings nearby for security purposes as well as raising prices and having more arbitrarily stringent security measures.

[kzt]

Yeah. I have a hard time believing that would last more than a couple of weeks in Shadowrun's volitile political climate.

Zurich orbital is a fragile tinkertoy that anyone with an ADA laser (much less an ABM or ASAT laser) could cut into bite sized pieces in an afternoon. It's amazing how astonishingly powerful the power of Plot Device is in SR, isn't it?

[Cardul]

You know, the people mentioning the possibility of disaster? I think they are right..which means, for a fictional setting intended for telling a story, that it is the BEST idea to build one! I mean, how big a MAJOR disaster can the Catapult have, or someone using a spirit to speed up existing rockets? But...the Space Elevator could have a really BIG one! It is so much better for a disaster plot then any of the other options! And they could even do a plot book around it, like with Emergence or the upcoming Ghost Cartels...

[suppenhuhn]

The climber also ignores atmospheric friction after the first 100km so no big whoop.

One advantage the catapult has is it doesn't carry a motor. Although the size of the motors isn't really that big if you're willing to take many hours to reach orbit, although that increases the life support system for passenger travel.

One big disadvantage that catapults have is that they have to launch with significantly greater than escape velocity. Meaning if you need 11kps to reach orbit, you probably start with 15kps at ground level and have slowed to 11.1kps at the edge of the atmosphere.

The other massive disadvantage of catapults is the ratio of size of the catapult vs. launchable materials. A small catapult requires more acceleration. More acceleration will start damaging the cargo. Sustained forces of 9-12G will kill most people. Short-duration forces of 40G cause significant trauma to people and is probably risky to many objects. Heck, freeze dried food probably risks being turned to powder under any more force. So let's set the limit at 40G.
40G = 9.81m/s^2 = 392.4 m/s^2. To reach 11kps at 40G takes 28 seconds and requires a 150km catapult (or appropriate number of times around a loop). To hit an assumed 15kps at ground level is 38 seconds and 283km of catapult/loop travel.

For a passenger catapult, limited to 7G, you require 218 seconds and 1600km of loop/apult. And that catapult better be depressurized or you've got ~3.5 minutes of ground level sonic boom. Plus it provides a constant 7G of acceleration.

I'm not sure that's easier than a space elevator. I mean, the elevator can be hand waived away with one leap of material science. "Tada, Unbreakium!"

The climber also ignores atmospheric friction below 100km as it's so slow, i just mentioned it to show that you only experience atmospheric drag at a very small part of your journey to space.
The top speed isn't a problem really as most electromagnetic catapult designs allow for 20km/s or more and 40G aren't really tht much as long as you don't intend to transport personnel that way but then the space elevator, at least in early stages, isn't meant to transport humans as well, the us navy is experimentiung with guided missiles shot from cannons at the moment and there you have thousands of G.

As for the leap in material science *cough* carbone nanotubes may have the tensile strength needed in theory but have yet to be made with such high specs. Also carbons generaly don't show any signs of stress or strain, they just break at a point eventually, making maintenance almost impossible. In addition due to the high forces at work here the failure of a tether will most likely lead to a cascade that can destroy the entire elevator.
Also note that all that has been done on elevators yet are the statics, noone has done any work of the dynamics of such thingies and the economics are all stuff people pulled out of their nose. Also noone has tested a remote power supply at ranges of 10000 or so km so i guess that would need quite a lot of work as well.
Imo nasa and all those affiliated groups are way too optimistic about this which is ok as they need to raise fundings but one should keep that in mind maybe.

Tether catapult? Do you mean a space hook or sky hook? Where you've got a rock and a long rope with a hook spinning (vertically) at the same rotational velocity as the planet's surface so that the hook hits the ground at essentially zero velocity?

In some ways I like those more than elevators since there's around a 50% chance that nothing slams into the Earth, assuming your "rock" is set up to fragment into sufficiently small parts that it won't survive reeentry. Flip side, you've got a ginormous rope of Unbreakium winging through the atmosphere. The effect of a hurricane worries me.

No it's just a kind of em catapult. Skyhooks are interesting though and pose way less engineering problems then an elevator. Also if you use those above the equator the chances of experiencing a hurricane are minimal.

[Particle_Beam]

Pfff, your own controlled water spirits can manipulate the weather. No fear for any hurricane at all. You could build it anywhere on the world, and you won't ever encounter any hurricane.