Watson GW-1 Windwagon

The Watson WG-1 Windwagon is a single-seat recreational ultralight designed in the United States in 1976 and marketed for homebuilding.^[1] Designer Gary Watson originally sold kits as well as plans, but later sold only plans. ^[1]

GW-1 Windwagon
Role	recreational ultralight
National origin	United States
Manufacturer	homebuilt
Designer	Gary Watson[1]
First flight	April 19, 1977[2]

Design and development

The Windwagon is a low-wing cantilever monoplane of conventional design with fixed, tricycle undercarriage, and a single-seat open cockpit.^[1][3] Construction is of pop-riveted metal throughout.^[1] The outer wing panels are removable to facilitate hangering and trailering.^[1][3][4]

Power is supplied by an air-cooled, tractor-mounted piston engine driving a propeller.^[1] The engine selected by Watson was an automotive Volkwagen air-cooled engine sawn in half across its crankcase to turn the flat-four engine into a flat-two^[1][3][4] (a modification called a "half VW"). Plans for the Windwagon included instructions for modifying a Volkswagen engine this way.^[1]

By 1987, Watson had sold over 1,025 sets of plans, and over 500 Windwagons had been built around the world.^[1]

The Hummel Bird is a development of this design.^[3]

Specifications (as designed)

Data from Jane's All The World's Aircraft 1987-88, p.732

General characteristics

• Crew: 1 pilot
• Length: 13 ft 0 in (3.96 m)
• Wingspan: 18 ft 0 in (5.49 m)
• Height: 3 ft 6 in (1.07 m)
• Wing area: 54 sq ft (5.0 m²)
• Empty weight: 273 lb (124 kg)
• Max takeoff weight: 485 lb (220 kg)
• Powerplant: 1 × Half VW 2-cylinder horizontally opposed air-cooled piston automotive engine, 30 hp (22 kW)

Performance

• Maximum speed: 135 mph (217 km/h, 117 kn)
• Cruise speed: 100 mph (160 km/h, 87 kn)(flaps and undercarriage down)
• Range: 300 mi (480 km, 260 nmi)
• Service ceiling: 12,000 ft (3,700 m)
• Rate of climb: 450 ft/min (2.3 m/s) max. climb at sea level
• Wing loading: 8.98 lb/sq ft (43.8 kg/m²)