Kawasaki Heavy Industries MBB/Kawasaki BK-117
Manufactured 1979–present 
First flight 13 June 1979

The MBB/Kawasaki BK 117 is a twin-engined light utility–transport helicopter. It was jointly developed and manufactured by Messerschmitt-Bölkow-Blohm (MBB) of Germany and Kawasaki of Japan. MBB was later purchased by Daimler-Benz and eventually became a part of Eurocopter, which was later rebranded as Airbus Helicopters. On 25 February 1977, MBB and Kawasaki signed a cooperative agreement to abandon their independent efforts to design twin-engined general purpose helicopters in favour of a collaborative venture to development of a new rotorcraft for that role. While the programme's costs were shared equally, the workshare was divided into certain areas of the design. MBB utilised their expertise .

Development

Origins

According to aviation author J. Mac. McCellan, the BK 117 has its origins in an earlier rotorcraft designed and produced by German aerospace manufacturer Messerschmitt-Bölkow-Blohm (MBB), the MBB Bo 105. This helicopter, which proved to be a commercial success, had made use of a revolutionary hingeless main rotor composed of fibreglass, which was developed by German engineer Ludwig Bölkow. Having established a reputation for reliability and safety, during the early 1970s MBB, along with one of its major shareholders, Boeing Vertol, began studying options for producing an enlarged derivative of the type to accompany the Bo 105. However, Boeing soon withdrew from the venture, leading to MBB searching for another partner; this was found in the form of Japanese company Kawasaki Heavy Industries.

On 25 February 1977, MBB and Kawasaki signed an agreement to cooperate on the development of a new rotorcraft. Under the terms of this agreement, the two corporations merged their previously separate projects to produce twin-engined general purpose helicopters, these being the Bo 107 by MBB and the KH-7 from Kawasaki. All of the privately incurred development costs were shared equally between the two partners; in November 1977, the programme received a huge boost when the government of West Germany announced that it would fund half of the costs of development. By April 1978, project definition studies had been completed, enabling the joint venture to proceed with the detail design phase of development. Wiki Link