The Hughes 300 was followed in 1969 by the improved Hughes 300C (sometimes 269C), which first flew on 6 March 1969 and received FAA certification in May 1970. This new model introduced a more powerful 190 hp (140 kW) Lycoming HIO-360-D1A engine and an increased-diameter rotor, giving a payload increase of 45%, plus overall performance improvements. It was this model that Schweizer began building under license from Hughes in 1983. In 1986, Schweizer acquired all rights to the helicopter from McDonnell Douglas, who had purchased Hughes Helicopters in 1984, and renamed it McDonnell Douglas Helicopter Systems. For a few years after, Schweizer acquired the FAA Type Certificate known as the Schweizer-Hughes 300. While Schweizer made over 250 minor improvements, the basic design remained unchanged.