Another, more successful, programme was the US's Bell X-1, which also was equipped with a straight wing. According to Miles Chief Aerodynamicist Dennis Bancroft, the Bell Aircraft company was given access to the drawings and research on the M.52.[50] On 14 October 1947, the Bell X-1 performed the first manned supersonic flight, piloted by Captain Charles "Chuck" Yeager, having been drop launched from the bomb bay of a Boeing B-29 Superfortress and attained a record-breaking speed of Mach 1.06 (700 miles per hour (1,100 km/h; 610 kn)).[2] The news of a successful straight-wing supersonic aircraft surprised many aeronautical experts on both sides of the Atlantic, as it was increasingly believed that a swept-wing design not only highly beneficial but also necessary to break the sound barrier.[47]