 The aircraft incorporated aerodynamic control principles covered by patents issued to Fred Weick, an early aeronautical engineer who went on to design and market the Ercoupe.Since it had no rudders (or rudder pedals), it was simpler to fly (it had a single control wheel, which controlled the ailerons and elevator), and was considered spin-proof.The aircraft was certified in 1941 with a placard that stated that the aircraft was characteristically incapable of spinning.