Single-seat single-engined mid-wing mono-plane with conventional three-axis control. Wing has swept back leading and trailing edges, and tapering chord; cruciform tail. Pitch control by fully flying tail; yaw control by fin-mounted rudder; control inputs through stick for pitch/roll and pedals for yaw. Wing braced from above by cables; wing profile Karman; 100% double surface. Undercarriage has three wheels in tricycle formation. Push-right go-right nosewheel steering connected to yaw control. Aluminium-tube/glass-fibre fuselage, partially enclosed. Engine mounted above wing driving pusher propeller.
Col Winton's Grasshopper won an award for the best foreign ultralight at the 1981 Oshkosh being a sophisticated design, even by 1983 standards. Using Karman aerodynamics for both fuselage and wings, this machine was originally powered by a 432 cc two-stroke developing 23 hp. However, following its win at Oshkosh, Pterodactyl Ltd agreed to market the aircraft in the US, using a 30hp Cuyuna, while Col himself had plans to re-engine the machine with a 440 cc Robin.
In concept the Grasshopper is a mixture of composite and tube-and-Dacron construction. The fuselage is principally made from glass-fibre, while the wings are tube-and-Dacron with glass-fibre leading edges and tips. Wings can be removed for transport and storage. The undercarriage has suspension on all three wheels and sometimes wheel spats are fitted.
Tolhurst purchased the moulds and rights from Colin Winton and produced an updated model at Camden, Sydney, Australia.
Engine: Robin EC44PM
Prop: VAC 36 x 50
Wingspan: 28 ft 8 in
Length: 16 ft
Empty wt: 122 kg
AUW: 249 kg
Cruise: 60 kts
Max level speed: 75 mph, 120 kph