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Consider a very conveniently placed asteroid in orbit around the earth, and we hang the space elevator off of that. It doesn't have to be at the geostationary altitude but it would probably help if it was (I think).

The elevator is made of 2 ribbons, with (at an optimal altitude) a sequence of wings between them, it looks like a ladder of wings. The elevator is going at a fairly high speed relative to the earth and in a region with little wind, maybe somewhere near the equator.

As far as I can tell the main issues are still with the strength of the ribbon, it will need to be strong enough to handle the drag force and the weight, but hopefully the weight issue will have been significantly reduced by adding wings. It would be dangerous to have this thing even come close to the ground, so you would have to dock with it from an aircraft. You would want the docking part significantly lower than the wings because the downwash would be monstrous.

Oh and of course it would need some way to prevent bird strikes, I feel like they might notice a giant structure flying through the air but those idiots hit 747s we can't trust them.

a) Once one gets the asteroid in place is this idea impossible to manufacture? Or just unreasonably expensive?

b) have I missed anything important in my considerations?

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    $\begingroup$ Why do you want wings? At the moment a space elevator with/without wings is in-feasible? What exactly is your question? $\endgroup$ – Aron Apr 20 '16 at 4:22
  • $\begingroup$ The biggest issue with space elevators right now is that there is no material strong enough to support its own weight, with wings the weight is significantly decreased but there are other issues. I want to know if adding wings is worth the trouble. $\endgroup$ – Taha Apr 20 '16 at 9:49
  • $\begingroup$ I have absolutely no idea what you mean by wings. Airplane wings? Bird wings? Paper mache wings? Helicopter rotor blades? $\endgroup$ – Xandar The Zenon Apr 20 '16 at 14:55
  • $\begingroup$ @Taha Can you clarify why the elevator would need wings? For lift for the bottom end of it while it is above ground? Many people talk about space elevators being anchored to the ground or to a floating platform at sea. $\endgroup$ – RichS Apr 20 '16 at 17:44
  • $\begingroup$ If I understand Taha's question correctly, he's asking about whether borrowing the engineering principles behind a kite will help or hinder a space elevator. $\endgroup$ – Stephen Voris Apr 20 '16 at 20:19
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Sadly, the answer is

No.

  • Your elevator would be in a non-stationary orbit. This means its lower end would travel above ground at orbital speed, i.e. some 7-8 km/s. How would you suggest it picks something up?

  • If you decide to hang your construct from a geostationary orbit (some 35'000 km altitude), your entire idea will stop working, as the wings will hang dead in the air and will at most get a little bit of lift from wind, which is not always predictable.

  • While the wings might generate lift, they will only do so if kept in place horizontally.

  • The horizontal force through drag would be translated into even more strain on the cables vertically, which essentially negates all the benefits you're hoping to achieve in terms of reducing strain on the cables.
  • I'm too lazy to do the math on this, but it might quite possibly create even more strain on the cables than hanging them without wings.

Thought experiment:
You are in a plane holding a rope through the window, it is trailing behind you. Now you do the same thing, but with some model-airplane-wings attached to the rope. Will your rope get lighter?

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I may have misunderstood your description, but it sounds like you have a non synchronous orbital elevator which orbits the Earth rather than being anchored in one spot.

Such elevators are indeed possible (there are actually two basic types, an elevator which "hangs" in the atmosphere as it orbits and a Morovec "Rotovator", which turns about its own axis and can be though of as "rolling" around the world, periodically dropping an end into the atmosphere to pick up or deliver cargo.

enter image description here

The issue is these devices are incredibly massive, especially compared to the cargo they pick up, and are moving at orbital velocity, some 7.8 km/s. In Imperial measurement, this is 17,450 mph, or roughly Mach 22.

Your problem at this speed would be frictional heating and drag (especially drag slowing down and causing a momentum tether the mass of a supertanker to de orbit). Having a set of wings either individually or in series will probably have a "null" effect, with the extra lift being cancelled out by the increased drag of all the airfoils. Most conceptual designs have the tether orbiting at such an altitude that the end is extremely high in the stratosphere (if not higher), and only a scramjet or rocket reaching the edge of space is capable of reaching the end of the tether and hooking p for a lift into space.

If there is a place for airfoils, perhaps there might be a set of control vanes at the terminal end to give some fine control to facilitate docking, somewhat like the booms used by the USAF to fuel aircraft:

enter image description here

As a final note, while having multiple paths to climb and descend the tether is good in theory, the need to minimize heating and drag argues for only one actual "end". Multiple paths can be accessed higher up, here is a diagram with several designs for possible orbital tethers:

enter image description here

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