My curiosity is probably a bit outdated. The original KR designs called for a material called Dynel. From what I have read, this was more of a draper's synthetic fabric like rayon etc. - not intended to be a structural medium.
It is however reported to be very effective (strong / tough?) when used as a composite fabric. The following ectract from an article by jck Cox (At Oshkosh) on the KR1. -- "Dynel" is a synthetic fiber made by Union Carbide. It is used on the KR-1 in much the same way as fiberglass cloth is used to make cowlings, etc. on other planes. Dynel has the advantage of being four times as strong as glass, but only half as heavy. The cloth is very soft and can be stretched to fit almost any shape. 4 ounce per square yard This outer shell is incredibly light and strong. This writer personally observed Ken Rand walking up and down the wing of the KR-1, and at the risk of a repair bill and/or a fat lip, I took the thin trailing edge of the elevator between two fingers and tried hard to deform it in any direction If it was cost effective and did the job, there must be reasons why it is no longer used - does anyone know what those reasons are. After a brief encounter with Kevlar, I hope to never use this uncooperative material ever again - even if it is 6 times as strong, half the weight and free. What is working best for a KR2S? Steve J
