Douglas D-558-1 Skystreak airplane model. ,A single-place, straight-wing, jet-powered aircraft, the D-558 I "Skystreak" was manufactured by Douglas Aircraft. It was designed to investigate jet aircraft characteristics at transonic speeds, including stability and control and buffet investigations. Much of the research in the public mind performed by the D-558-1 Skystreaks, was quickly overshadowed by Chuck Yeager and the X-1 rocket plane. The Skystreak performed an important role in aeronautical research by flying for extended periods of time at transonic speeds, which freed the X-1 to fly for limited periods at supersonic speeds.