During the immediate post-war era, several nations were conducting research into high speed aircraft. In the United Kingdom, work commenced during 1943 on the Miles M.52, a high-speed experimental aircraft equipped with a straight wing that was developed in conjunction with Frank Whittle's Power Jets company, the Royal Aircraft Establishment (RAE) in Farnborough, and the National Physical Laboratory.[48] The M.52 was envisioned to be capable of achieving 1,000 miles per hour (1,600 km/h) in level flight, thus enabling the aircraft to potentially be the first to exceed the speed of sound in the world.[48] In February 1946, the programme was abruptly discontinued for unclear reasons.[49] It has since been widely recognised that the cancellation of the M.52 was a major setback in British progress in the field of supersonic design.[3]