The Pterodactyl Ascender is a family of U.S. designed and built ultralight aircraft that were sold in kit form between 1979 and 1984 under Pterodactyl Limited and is currently being sold by DFE Ultralights. With a total production of 1,396 aircraft between 1979 and 1984 plus limited production today as the DFE Ascender III series, the aircraft has been one of the most influential designs in ultralight aviation. Design and development The Pterodactyl designs have their roots in the Manta Fledge hang gliders of the 1970s. The Fledge was designed by Klaus Hill and produced by Manta Products in a series that ran from the Fledge I to the IV, with numerous sub models designated by letters. The Fledge series were of a "rigid-wing" type, as opposed to the predominantly "flex-wing" hang glider designs then common. These designs all featured weight-shift pitch control and tip-rudders for yaw and roll control. The tip rudders were controlled by control-bar sliders which deployed one tip rudder at a time to create a yaw. The glider's swept wing then translated the yaw into a matched rolling motion. The Fledge series were considered to be high performance hang gliders during their production run in the 1970s. California inventor Jack McCornack took the Fledge IIB wing and designed a tubular assembly that replaced the Fledge's hang glider seat with a reclined pilot seat, wheeled landing gear and engine mount for a pusher powerplant. The aircraft used a mouth-controlled throttle, as both hands were used on the tip rudder twist grips which were retained from the Fledge. The aircraft was tailless. Power was supplied by a two-stroke Xenoah engine of 16 horsepower driving a 36-inch propeller. This new design, named the Pterodactyl Fledgling, was first flown in 1977. It is also referred to variously as the Pterodactyl Fledge and Pfledge. The aircraft was first publicly displayed at an ultralight fly-in at Gilroy, California in 1978. McCornack formed Pterodactyl Limited to produce an improved version of the design, designated the Fledge X powered by the Xenoah 242 engine. In 1979 McCornack and his flying partner, Keith Nicely, flew two improved Fledglings from their base in Monterey, California, to Oshkosh, Wisconsin, where they made a positive impression on the large gathering of pilots at the EAA annual convention there. At the convention they were invited by Mother Earth News magazine to fly the aircraft on to the Atlantic coast