Photograph:
Ken Brock KB-3 Gyrocopter N112SW (Author’ collection)
Country of origin:
United States of America
Description:
Single-seat sport gyroplane
Power Plant:
One 63 kw (85 hp) Volkswagen four-cylinder horizontally-opposed air-cooled engine
Specifications:
- Rotor diameter: 6.7 m (22 ft)
- Length: 3.65 m (12 ft)
- Cruising speed: 121 km/h (75 mph)
- Minimum speed: 29 km/h (18 mph)
- Rate of climb: 366 m/min (1,200 ft/min)
- Service ceiling: 3,048 m (10,000 ft)
- Range: 241 km (150 miles)
- Take-off run: 91 m (300 ft)
- Landing run: 3 m (10 ft)
- Empty weight: 104 kg (230 lb)
- Loaded weight: 272 kg (600 lb)
History:
Ken Brock Manufacturing Inc of Stanton, California, USA, since 1957 has been building a series of single-seat open frame gyroplanes, models including the KB-2 and KB-3. Similar in appearance to the Bensen series, which first became available in 1953, a number of refinements were made to that design, including a modified control system.
The type was available in kit form and many examples have been completed around the world. The design used a riveted aluminium rotor blade with an adjustable hub.
Production of gyroplanes commenced in 1960 and the Company has patented a number of features of its designs, including a fuel tank under the seat, an aircraft-type control system and a quadrant throttle system.
A number of examples have been registered in this region, including ZK-RBO (c/n NZRA/R39), ZK-RBL (c/n 069/MAANZ/5070), and ZK-REG (c/n NZRA/R51).
The type held several records for autogyros, including a flight from coast to coast involving a KB-2 in 1971, flying from Long Beach, California to Kitty Hawk in North Carolina, covering 5,472 km (3,400 miles) in ten days. This machine was later placed on display at the Experimental Aircraft Association (EAA) Museum at Oshkosh in Wisconsin.
A number of engines could be installed but usually a Volkswagen conversion or a 67 kw (90 hp) McCulloch were installed.
The KB-3 was a single-seat variant aimed at the ultralight market, was fitted with a 48 kw (65 hp) engine, had a max speed of 113 km/h (70 mph) and had a weight of 113 kg (250 lb).