I'd like to cover the Chrysalis 2M with dope and silkspan. Do you think it'll have flutter problem?

From : Don Stackhouse

Quite honestly I'm not sure. We have not tested that combination, and I don't have any good data on how the stiffness of silkspan and dope compares to Monokote or Ultracote. Also, there is considerable variation among the different brands and weights of silkspan out there. My gut feel says it would probably work with medium or heavy silkspan, but that's a guess.

The other concern is that I've seen silkspan go slack when exposed to high humidity. In that case you could have a problem.

Another possibility that would be more durable and certainly stronger and stiffer would be silk or nylon and dope. Sig and K&S both make silks or silk substitutes that should work fine.

One other option to improve the torsional stiffness of the wing and make it less sensitive to the properties of the covering is to fit some diagonal bracing between the leading edge and the front of the main spar on the inboard panels. Make them from 1/16" hard balsa sheet. They're roughly triangular, about 5/8" high at their aft end where they tuck into the corner between the rib and the front of the spar, and at the other end cut a radius to fit against the back of the leading edge dowel. The top and bottom edges are straight. Run them zig-zag fashion between the leading edge and the spar, one running diagonally between each pair of ribs, from rib "B" through rib "J". This will add quite a bit of additional torsional strength and stiffness, as well as reinforcing the leading edge structure against dings from those inevitable impacts with rocks, shrubbery, sapling trunks, your ankles, etc.. I recently added these to the wing of the prototype electric 2-meter Chrysalis, and they did make a very noticeable improvement.

Don Stackhouse
DJ Aerotech