Greg Nolan
enthusiast
See this thread on the WoodenBoat Magazine forums for a discussion by Todd Bradshaw and photos of a Peter Mueller Willits with a removable keel, batwing sail, ingenious rudder gear, and his own design of a sail modeled on the Willits sail, using a bedsheet:
http://forum.woodenboat.com/showthread.php?136837-Holy-Sheet-Batwing
http://forum.woodenboat.com/showthread.php?136837-Holy-Sheet-Batwing