The correct answer is the DeHavilland DH.108. Britain’s DH.108 was built to an Air Ministry specification E 18/45, originally to investigate the behaviour of swept wings at low, medium and high subsonic speeds. Work began in October 1945, three prototypes being ordered. This first prototype, powered by the Vampire’s 3,000 lb. st. DH Goblin DGn.2 turbojet, was essentially a low-speed aircraft, capable of a maximum speed of 280 mph (451 km/h). The second prototype, TG306, was intended for research at higher speeds. Wing sweepback was increased to 45°. Leading edge slots were automatic and lockable by the pilot, and powered flying controls were provided. The third prototype, VW120, did not fly until 24th July, 1947. The pilot’s seat had been lowered for the fitting of a low-drag canopy, and a pointed nose fitted, increasing overall length to 26 ft. 9½ in. (8.165 m). On April 12, 1948, the aircraft set a new 100 km (62.1 mile) closed circuit speed record of 605.23 mph (974 km/h), flown by John Derry, and it was certain that it could better the top speed of the preceding aircraft.
The correct answer was submitted by jeaton, intruder38, PontiacRich, and skybolt2003, thus continuing the tie. The next tie breakers for jeaton, intruder38 PontiacRich and Skybolt2003 only will post shortly, so start studying, fellows! and thanks to all who participate (and send me great extra info!)
Brian [C):-)]