In this NACA High-Speed Flight Station photograph the X-3 Stiletto is viewed from above and looking at the left side. The X-3 Stiletto was a single-place jet aircraft with a slender fuselage and a long tapered nose, manufactured by the Douglas Aircraft Company. The X-3's primary mission was to investigate the design features of an aircraft suitable for sustained supersonic speeds, which included the first use of titanium in major airframe components. It was delivered to the NACA High-Speed Flight Station in August of 1954 after some Douglas and Air Force evaluation testing.