Plane-less Wing-Walking

In the early days of aviation, a daredevil called a "wing walker" would sometimes climb onto the upper wing of a biplane, usually using some cords to maintain stability, while the pilot did some aerobatics.

Nowdays we don't see that so much any more, but the modern popularity of extreme air sports can offer us a variation on that theme.

Imagine jumping out of a plane with a wing. You stand on the wing and control its attitude with various cords, not to mention your physical position, while gliding all the way down to the ground. An expert should not need a parachute (just a prayer).

How large does the wing need to be? Start with a calculation involving paragliders. They are somewhat wing-shaped and quite sufficient to gently land the user; how much surface area do they have to interact with the air? What if it was doubled?

Weight is a factor, of course. A wing stiff enough to stand on will not be made of fabric only, and the extra weight will require more total surface area for the wing.

Modern materials include a lot of carbon-fiber composites, which are quite appropriately strong and lightweight. You can assume the following descriptions will make significant use of it.

I'm imagining a central platform on which the user can stand and move about somewhat. It does not need to be especially wide, because standing off-center will be adequate to tilt the wing one way or another. The cords that the rider would handle can allow the "dihedral" of the wing to be adjusted.

I'm also imagining a telescoping design, to allow the wing to take up a small space when carried onto a plane by the jumper. Sections would telescope in both directions away from the center, of course.

The extension of the wings, from the central platform, logically works against the usage of the cords. It will be necessary for each section that telescopes outward to lock into place after doing so. Methods for extending the wings can be as simple as being pulled out by the jumper, while in free-fall, or as complicated as being pushed out by springs (but that adds weight).

I'm going to suggest a mechanism that uses air flow, to extend the wings. The user would stand on the platform as soon as possible after jumping out of the plane. The flat face that encounters air, below the rider, offers an excellent collection area for air, to inflate/extend the wings. If the wings were swept back slightly, that would help, too.

If the entry for that air was valved and controlled by the rider, then the total wing span could be adjusted (toward being wider) at any time during the fall/glide. The initial part of the jump can therefore be very much like the existing sky-surfing sport, offering a familiar starting point for this divergence from it.

Also, the construction design should arrange that each section be valved, and each valve should automatically open only as the previously telescoped section locks into place. The rider only needs to control the first valve for the initial sections.

There is a particular design of airfoil that would be greatly accommodating for this Idea. It is called the "Klein Fogelman" airfoil (see link). It offers a flat place onto which to walk, integral to the overall design, and the "rib" sections of the design are much simpler and easier to manufacture than the standard airfoil shape (they will weigh less, too). The design also naturally allows for extension of the "chord" of the wing, offering an easy way to increase the total surface area that interacts with the air.

Although the telescoping tubes of this wing, and the rib sections attached to the tubes, would be made of hard material, in-between them can be ordinary wing or parachute fabric material, that becomes taut as the sections telescope outward and lock into place. I'm estimating that the total tip-to-tip span of the wing may not need to exceed 7 meters.

Skids would be appropriate, for when the wing finally reaches the ground.