Hawker Siddeley Harrier single lever added in the cockpit. For horizontal flight, the nozzles are directed rearwards by shifting the lever to the forward position; for short or vertical takeoffs and landings, the lever is pulled back to point the nozzles downwards. The Harrier has two control elements not found in conventional fixed-wing aircraft: the thrust vector and the reaction control system. The thrust vector refers to the slant of the four engine nozzles and can be set between 0° (horizontal, pointing directly backwards) and 98° (pointing down and slightly forwards). The 90° vector is normally deployed for VTOL manoeuvring. The reaction control
Hawker Siddeley Harrier designated "P.1127 (RAF)", of which the first made its maiden flight on 31 August 1966. An order for 60 production aircraft, designated as Harrier GR.1, was received in early 1967. The aircraft was named after the Harrier, a small bird of prey. The Harrier GR.1 made its first flight on 28 December 1967. It officially entered service with the RAF on 18 April 1969 when the Harrier Conversion Unit at RAF Wittering received its first aircraft. The aircraft were built in two factories—one in Kingston upon Thames, southwest London, and the other at Dunsfold Aerodrome, Surrey—and underwent initial testing at