|
Encyclopedia - Avro Vulcan
A specification was issued in January 1947 (changed in June 1948) that called for a bomber that could carry a bomb weighing 4,536kg (10,000lb) to a target that was 2,780km (1,725mi) away. The aircraft had to be able to climb to 50,000ft (15,240m) and its approach speed could not exceed 104kt (193km/h; 120mph). This was well within reach, but for some reason the aircraft may not have a gross weight exceeding 45,360kg (100,000lb).
The design team at A.V. Roe Ltd. under the leadership of Roy Chadwick accepted this challenge, but by the winter of 1947 was only able to get the gross weight to 88,452kg (195,000lb). After removing the tail and replacing it with a large delta wing they managed to get the gross weight down to 61,236kg (135,000lb) by March 1947. The fuselage was then shaped to merge into the wing at the rear of the fuselage, with two Bristol BE.10 Olympus turbojets on either side of the fuselage shaped into the wing. As from the middle of 1947 the aircraft was further designed under the designation Avro 698.
The first prototype, VX770, was completed before its engines so four Rolls Royce Avon RA.3s were fitted. It made its first flight at Woodford on 3 August 1952. The second prototype, VX777, was fitted with Olympus Mk.100 engines, as well as having a lengthened fuselage to increase fuel capacity and to accommodate an extended nose leg.
The first production aircraft made its maiden flight on 4 February 1955 powered by Olympus Mk.100 engines. These were later to be replaced by Mk.101, Mk.102 and eventually the Mk.104, which became the standard engine for the Vulcan, developing 6,078kg (13,400lb) of thrust. The increased power meant increased speed, and this resulted in a mild buffeting in the outer wings which drastically increased fatigue. This problem was solved by increasing the chord of the outer wings, and curving the leading edges down, similar to what the Concorde had in later years. No.230 Operational Conversion Unit stationed at Waddington was the first squadron to receive Vulcans, and the first one was delivered on 20 July 1956.
Bristol experienced enormous success with their Olympus engine, and the Mk.200 engine delivered 7,258kg (16,000lb) of thrust. The increased performance meant yet another redesign of the wing, with the span increasing by 3.66m (12ft). Avro fitted this new wing to VX777, which first flew on 31 August 1957. The Vulcan no longer had separate ailerons and elevators, but instead had eight elevons each with its own power unit. The air intakes were enlarged for the more powerful engines, and the structure strengthened to allow operations at a gross weight exceeding 90,720kg (200,000lb). The new Vulcan received the designation Vulcan B.2. The last Vulcan, XM657 was delivered to 35 squadron on 14 January 1965.
The Vulcan was used only by the RAF, and its roles included nuclear deterrence, aerial refuelling, high- and low-altitude bombing, maritime reconnaissance, ECM, and later as an engine testbed for the Concorde. The Vulcan was replaced by the Panavia Tornado.
| |
