Country of origin:

United States of America

Description:

(J-4B)

Single-seat sport gyrocopter

Power Plant:

One 75 kw (100 hp) Continental O-200 four-cylinder horizontally-opposed air-cooled engine

Specifications:

• Rotor diameter: 7.01 m (23 ft)
• Length overall: 3.71 m (12 ft 2 in)
• Height: 2.34 m (7 ft 8 in)
• Disc area: 38.55 m² (415 sq ft)
• Max speed: 193 km/h (120 mph)
• Cruising speed: 156 km/h (97 mph)
• Max rate of climb at sea level: 457 m/min (1,500 ft/m)
• Service ceiling: 4,572 m (15,000 ft)
• Range: 436 km (270 miles)
• Take-off distance: 46 m (150 ft)
• Landing distance 0 to: 6 m (0 to 20 ft)
• Fuel capacity: 57 litres (12.3 Imp gals)
• Empty weight: 200 kg (441 lb)
• Loaded weight: 340 kg (750 lb)

History:

The Barnett Rotorcraft Company of Olivehurst, California, USA for some years designed and built two generally-similar ultralight gyroplanes known as the J-3M and J-4B. The basic difference between the two was the engine installed, the J-3M being a utility model with a flat-sided cabin with fabric covering and powered by a 48 kw (65 hp) Continental A65 engine; whereas the J-4B was a higher performance model fitted with a fibreglass nacelle for the pilot and powered by a 63 kw (85 hp) Continental C85 engine. The rotor blades were of spruce with a single internal steel spar and fibreglass covering. The fuselage structure was of all-metal and it had a fixed tricycle undercarriage.

A few examples have been registered in this region, including ZK-RBF (c/n 1985-2) and ZK-RBM (c/n NZRA/06/2) in New Zealand.

Barnett Rotorcraft also produced the J-4B-2, a two-seat training variant with the Continental O-200 engine, which was also available in kit form. It had slightly larger overall dimensions and had an enclosed cockpit. It had a max speed of 180 km/h (112 mph), a cruising speed of 150 km/h (93 mph) and empty and loaded weights of 232 kg (512 lb) and 492 kg (1,085 lb).