Video showing G007 clip from Ron Gray's film.   Bristol Belvedere twin-rotor helicopter. Bristol Type 173, 191 and 192 Belvedere. Britain's first tandem-rotor helicopter first flew on 3 January 1952.   It had tandem rotors and was capable of carrying 10 passengers.   This prototype was subsequently evaluated by the Royal Navy, in tests carried out from the aircraft HMS Eagle.   The sea trials were successful and in 1956 an order was placed for 68 Bristol 191 ASW models. Meanwhile, the RAF ordered 26 examples for use as heavy transport helicopters.   In 1957, however, the Navy order was cancelled as part of defence cuts and the RAF version only entered service in 1961 as the Belvedere.   The all-purpose helicopter was withdrawn from service in 1969.   Bristol's proposal for a 23-seat passenger version (192C) for BEA was never to progress beyond the project stage.   The airline selected proven Westland-built versions of American helicopters in preference to the British design.   Specifications apply to the Bristol Belvedere HC-Mk 1. Crew: 2/3; Powerplant: Two Napier-Gazelle NGa.2 Mk. 100 turboshaft engines each rated at 1,092 KW ( 1,465 HP).   Performance: Max speed 222 Km/h (138 mph) at optimum altitude, combat radius 740 Km (460 miles); service ceiling 5,273 m (17,300 ft); Dimensions: rotor diameter 14.91m (48t 11in), length 27.36 m (89 ft 9 in); height 5.26m ( 17 ft 3 in); Weight: 5,277 Kg (11,634 lb); Armament/payload: up to 18 fully armed troops or 2,722 Kg (6,000 lb) of freight. (Thanks to "The Encyclopedia of Aircraft" by Robert Jackson). There is no sound with this clip.   This clip runs for 27 secs. (Thanks to Ron Gray for original film.)