An armament of twin 0.787 in (20 mm) cannon was planned and provision was made to provide for a fixed tricycle undercarriage for flight development and operation from shore bases. It was thus relatively simple to incorporate a retractable undercarriage in the design when Admiralty interest in the flexible deck concept waned in late 1947 and the fighter was modified as the more conventional Type 508.
Three aircraft were ordered to Specification N.9/47 for a naval fighter, and, configurationally similar to the Type 505 apart from the undercarriage, the first of these flew on August 31, 1951. The second, as the essentially similar Type 529 (featuring straight wings, a slightly re-designed tail with variable incidence and strakes, and changed intakes), followed a year later, on August 29, 1952.
Prior to these events, in February 1950, the contract covering the third prototype was amended to introduce sweptback wings, and this, as the Type 525, became, in effect, the prototype of the Scimitar. The Types 508 and 529 were each powered by a pair of 6,500 lb (2,948 kg) s.t Avon RA3 engines and had provision for an armament of four 0.787 in (20 mm) cannon. The data relate to the Type 529.
Span: 41 ft 0 in (12.50 m)
Length: 50 ft 0 in (15.24 m)
Height: 11 ft 7.5 in (3.54 m)
Wing area: 340 sq.ft (31.59 sq.m)
Weight empty: 18,460 lb (8,373 kg)
Loaded weight: 22,584 lb (10,244 kg)
Max speed: 607 mph (977 kmh) at 36,000 ft (10,975 m)