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New Single-Skin Kites

A new crop of Single-Skin traction kites, including an early peek at a "secret" FlySurfer prototype-


The fabric load-curtains that distribute bridle stress to the skin can perhaps be bettered by also running span-wise; thus forming a sort of waffle-grid bottom surface (include water/sand drain holes). Some similarity cases include hot Maori kite wings (with a rough grid bottom wattle texture), dimples on a golf-ball, and NASA-derived bluff-body fairings (based on box cavities). The principle involved is that a ball-vortex forms in each pocket created, and acts as sort of low-drag aero ball-bearing (or isolated turbulators on a wing top, to keep flow attached). There is also the possible helpful effect of more close-entrained air mass/intertia, with flight characteristics closer to double-skin. A single spanwise load-curtain at or inside the B-line might be ideal, to help keep the LE half-pipe pressurized. This is more a stagnation effect than a line vortex.

Word is that these SS kites do water-launch. These early single-skins are more technical (tricky) to fly, which limits their appeal, but there are many improvements still waiting to be tried...

--------Random Notes-----------

Kite line or membrane under tension acquires structural stiffness comparable or superior to "rigid" wing structure. There is no inherent velocity limitation on sufficiently-tensed single-skin wings in most of our flight regimes.

If one measures the total structural stiffness of an optimal soft-kite arch, including the ground between anchors, it far exceeds a single-anchor rigid kiteplane in the same space.

Aluminum can cheaply offer total protection of thin wing membranes from UV, and also carry a large amount of electrical surface current. Such a 2D conductor can sustain itself in flight, as integral wing surface.

Comment and development of this topic will be occurring here.       
All, send notes, links, drawings, papers, videos, plans, safety-critical findings, and photographs!

  • Terms and aspects:   
    • Roots of SS: Rogallo wing patent on single-skin roots, parachute canopies, spider webs, hung laundry, play sail, sails, Barish Glide Wing,
    • Framed single skin.
    • Enhanced single skin.
  • Related links and concepts:
  • Commentary is welcome:
    • Dave Culp sparked the single-skin powerkite revival, a direct influence to many kite design pros (Mothra is SS). The AWES Forum has for years carried the SS torch (in the face of the rigid-wing bubble). A growing subculture is making NPWs and newer SS concepts. Our friends at Ozone have been hard at work with new PG and PK designs, with more expected. Now Peter Lynn and Reinhart (via FlySurfer) have made huge advances, and almost anyone can now buy, make, or borrow the new wings-
      Peter Lynn is back, and SS is his obsession. The French kite sport interview links add great details-
      Navigate the full content of Reinhart's wonderful SS work for lots of good info-
      DaveS, 13Nov2013   Discuss: airbornewindenergy10633

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