Issues with rigid wings and possible solutions (reply to Dave Santos)

Engineering Crosswind Kites / Planes
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Rigid blades are not doomed in a crash.
Daisy testing demonstrated repeated tip ground-striking of rigid kite turbine blades.
The same rigidised foam blades which dug small channels still fly fine with little damage and no material loss.

Today - I blew out 2 cell seams on an 11m foil kite and within an hour burst the bladder of a 12m LEI.

Sure a similarly sized rigid would have been damaged by the same treatment.

A small foil can run full speed into the ground with no problems

Large kites are not resiliant is my general rule. (excludes single skin soft kites… Dare you try flying a huge one though)

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Only larger “rigid blades” (spars >3m L) are “doomed in a crash”.

Single-Skin KiteShip ship-kites and Mothra1 at >300m2 scale have been flown without much fuss by the experts. These represent the most crashworthy approach to large powerful AWES wings.

Velcro blow-out panels seem to protect parafoil cells from bursting when “thumped”. A blown parafoil cell is a simple repair (super-glue field-repair, even). A composite airframe is reliably destroyed by full-velocity crash.

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An example is given on KiteGen Research » KiteGen Power Wing.

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