Abstract: An assembly for providing flexure to a blade of a rotary blade system, the assembly including an upper support plate having an upper curved surface, a lower support plate having a lower curved surface, and a yoke positioned therebetween. At least one of the upper and lower yoke surfaces having a layer of cushioning material positioned thereon and secured thereto. The layer of cushioning material extending along and following the general contour of yoke surface, and the layer of cushioning material directly contacting a support plate. Another embodiment is an assembly for providing flexure to a blade of a rotary blade system, including, an upper support plate having an upper curved surface, a lower support plate having a lower curved surface, and a yoke positioned therebetween and directly contacting the support plates wherein one of the curved surfaces is a non-circular arc that does not form part of the circumference of a circle.

Abstract: The present invention relates to a board 1 suitable for use in descending a snow slope. The board 1 has a generally flat elongate base 15, a forward portion 2 with an upturned leading edge portion 12, a user support portion 4 and a rearward portion 3 comprising at least partly independently movable left and right support portions 18, 19 extending generally alongside each other rearwardly from said forward portion 2.The base 15 has outer side edges 7, 8 of generally angular cross-sectional shape for biting into the surface of a snow slope during turning in use of the board 1. The side edges are furthermore concavely arcuate, in plan view, so that the board 1 is substantially waisted intermediate its ends 12 and 14 so that the board can proceed along an arcuate path when one of its side edges 8 is weighted and the other 7 unweighted.