Sperwill ST

The aircraft was designed to comply with the US FAR 103 Ultralight Vehicles rules as well as European regulations. It features a paraglider-style wing, single-place accommodation and a single 24.6 hp (18 kW) Hirth F-33 engine in pusher configuration with a 2.3:1 ratio reduction drive and a three-bladed, fixed-pitch wooden propeller. The fuel tank capacity is 9 litres (2.0 imp gal; 2.4 US gal). The aircraft is built from a combination of bolted aluminium and 4130 steel tubing and dismantles for ground transport.^[1]

As is the case with all paramotors, take-off and landing is accomplished by foot. Inflight steering is accomplished via handles that actuate the canopy brakes, creating roll and yaw.^[1]

Data from Bertrand^[1]

General characteristics

• Crew: one
• Empty weight: 28 kg (62 lb)
• Fuel capacity: 9 litres (2.0 imp gal; 2.4 US gal)
• Powerplant: 1 × Hirth F-33 single cylinder, two-stroke, air-cooled aircraft engine, with a 2.3:1 reduction drive, 18.3 kW (24.6 hp)
• Propellers: 3-bladed wooden, fixed-pitch