Duncan Simpson elected to go for a maiden flight late on 21 August and shortly after 1900hrs. XX154 lifted off from Dunsfold.
Duncan Simpson joined the De Havilland Aeronautical Technical School in 1945 and was there until 1948. The 3 year design course was extended by 6 months at the company's request.His practical experience was in Experimental Department at Hatfield 1946-1947 where he worked on DH106 DH108, Ghost-Vampire, Hornet, Mosquito and Dove aircraft. He joined the Aerodynamics department in 1947. He joined the RAF at 6 Flying Training School in 1949. He was awarded the Flying Trophy and Eustace Broke Loraine Trophy. He was with 222 Naval Squadron between 1950 and 1953 being Adjutant in 1951 and Deputy Flight Commander 1952-1953. He worked with the Day Fighter Development Unit at Central Fighter Establishment in 1953/4 and underwent trials on Meteor, Vampire, Venom, Sabre, Swift and Hunter. He joined Hawker Aircraft Limited in 1954 as a Test Pilot.Between 1954 and 1962 he worked on the production and development flying of Hunter aircraft and production testing of the Sea Fury.
On 12 August 1974, the first Hawk, XX154 was formally rolled out at Dunsfold, sporting the distinctive red and white gloss paint scheme that was characteristic of all RAF training aircraft at the time. The aircraft then passed to the Flight Test Department at Dunsfold, where it became the responsibility of Chief Test Pilot Duncan Simpson and Hawk Project Pilot Andy Jones to prepare the aircraft for its maiden flight.