Firebird Skysport CX
In an effort to reduce the drag as much as possible in the 1982 Firebird CX, the suppresson of the kingpost and all the top rigging is eliminating a good part of the profile drag but brought problems for the pitch stability and the structural strength in negative.
For pitch stability, three solutions were found: the truncated tips assure sail washout, a small keel post inside the keel pocket keeps the centre chord in place and the battens are reflexed at the back.
For strength in negative G there is an 8 inch long king post inside the profile and two carbon fibre compresson struts instead of side cables. With fairngs, the produce less drag than the to rigging would.
The control frame is wider than usual to keep the carbon fibre compression struts as short as possible.