Developed from the three-seat Bell 47G-3B, the KH-4 is a four-seat general purpose helicopter powered by a 201kW Lycoming TVO-435-B1A air-cooled engine. First flight Summer 1960. Apart from changes to cabin to accommodate extra passenger, and new supercharged engine, the KH-4 had a new instrument layout, modified control system and larger fuel capacity. A total of 338 built for civil and military customers between 1960 and 1975.
Jane's Helicopter Markets and Systems
* * *
A.J.Pelletier "Bell Aircraft since 1935", 1992
At the beginning of the sixties, Kawasaki decided to develop a version of the three-seat Bell Model 47G-3, with a stretched cabin to make room for two rows of seats. The first KH-4 flew in August 1962 and received Japanese type approval on 9 November of that year. By the beginning of 1972, 193 of the Kawasaki KH-4 had been built, 19 of which were assigned to the Japanese Army, 23 to the Thai armed forces, four to the South Korean armed forces and one to the Philippines.
G.Apostolo "The Illustrated Encyclopedia of Helicopters", 1984
Technical data for KH-4
Rotor diameter: 11.32m, length overall: 13.30m, length of fuselage: 9.93m, height overall: 2.84m, empty weight: 816kg, maximum take-off weight weight: 1293kg, maximum level speed: 169km/h, cruising speed: 140km/h, service ceiling: 5640m, hover ceiling in ground effect: 5485m, maximum range: 400km