The BK117 helicopter was developed jointly by Kawasaki and MBB of West Germany (currently Airbus Helicopters). In 1982, the twin-engine, multi-purpose, high-performance helicopter was type approved as the first domestically manufactured helicopter. Since then, it has been used for a variety of applications, including transporting cargo, rescue, patrol, and emergency medical services, steadily increasing sales. The design principle behind the BK117 was simple: to develop a helicopter that was safe and easy to use. To achieve this goal, the development team worked to overcome various technological challenges from the initial design stage.

First, the helicopter was to be equipped with two independent engines, each of which would be able to fly the helicopter alone should the other engine fail midflight. Second, the floors of the passenger cabin and cargo hold were to be on the same level, with sliding doors provided on both sides of the cabin and clamshell doors at the rear. Third, the transmission design was simplified for enhanced reliability. The BK117 helicopter is loaded with numerous features that enable a wide range of applications to be carried out flawlessly, instead of simply achieving safe flight. The emergency medical services (EMS) model whose development was announced in 1976 is enormously popular as a medevac helicopter.

This is because it perfectly embodies the design principle of a safe and easy-to-use helicopter. The BK117 helicopter has undergone a number of incarnations, starting from the prototype and then evolving from series A through C. The latest variant C-2 has obtained a larger fuselage in a full model change, in addition to improved flight performance. The engineers who developed the early models remarked, "Normally, it takes a decade before a development effort bears fruit. A manufacturer that does not give appropriate weight to this development process will lose the foundation on which to stand." This will to take on challenges still lives on 30 years after the first model was launched.