Hawker Siddeley Harrier as VTOL and STOL manoeuvres (where the traditional lift and control surfaces are useless) requiring skills and technical knowledge usually associated with helicopters. Most services demand great aptitude and extensive training for Harrier pilots, as well as experience in piloting both types of aircraft. Trainee pilots are often drawn from highly experienced and skilled helicopter pilots. In addition to normal flight controls, the Harrier has a lever for controlling the direction of the four vectoring nozzles. It is viewed by senior RAF officers as a significant design success, that to enable and control the aircraft's vertical flight required only a
Hawker Harrier February , the first of the competitors for the two specifications to fly. The Harrier was a two-seat biplane with single-bay wings powered by a geared Bristol Jupiter VIII radial engine. It was armed with one .303 in (7.7 mm) Vickers machine gun and one .303 in (7.7 mm) Lewis gun carrying a maximum of 1,000 lb (454 kg) of bombs. The prototype Harrier was tested at the Aeroplane and Armament Experimental Establishment (A & AEE) at Martlesham Heath in November 1927, where, while it met the requirements of Specification 23/25 and had satisfactory handling, the geared engine meant that