Invented by C.W. McCutchen in 1964, the Charybdis (from Greek mythology of a powerful whirlpool off the Sicilian coast) was designed after studying the flight characteristics of the maple seed falling from the tree. This design was scaled up from the .010 engine size to use the Cox .049 engine. The main wing uses a simple Clarke Y airfoil with 3" chord 36" long. The stab is 18" long and set at 5 degree incidence to the wing. The counterbalance sets the CG at about 1/4" ahead of the leading edge and keeps the wing level by centrifugal force.
Flights last a couple minutes on 1/2oz of fuel and then goes into auto rotation once the engine quits allowing a gentle descent back to earth. Monocopter