First British pilot to break Sound Barrier

David Lean’s 1952 film The Sound Barrier, and Neville Duke’s book Sound Barrier published the following year, created a romantic historical ideal surrounding the quest to go faster than the speed of sound.

After World War Two, Britain was still facing rationing, it had a massive ‘lease lend’ bill to pay off and the war-ravaged country had to be rebuilt. Despite this, the engineering minds of the British aviation industry felt compelled to continue the exploratory work begun during the war to build a supersonic aircraft, a machine which could travel at more than Mach 1.0. That’s around 767mph, depending on atmospheric conditions such as air pressure.

After the war, Britain’s Air Ministry signed an agreement with the United States in which the British Miles M52 aircraft designs were handed over. The Bell Aircraft Corporation then created its near-identical X-1, a fundamentally British design that went on to break the Sound Barrier with Chuck Yeager at the controls. The X-1 was powered by a rocket rather than a jet engine, however, and was launched in mid-air from a B-29 Superfortress. The British design had taken off and landed under its own jet power.

With the closure of Miles Aircraft, the development of Britain’s supersonic aircraft fell to De Havilland, which revealed its swept-wing DH108 Swallow in May 1946. It was loosely based on Messerschmitt’s pre-war, rocket-powered Komet fighter.

De Havilland’s second prototype flew at up to Mach 0.9, piloted by Geoffrey De Havilland, the company founder’s son. Tragically, he was killed over the Thames Estuary while testing. This set the design process back, but in July 1947 a third prototype DH108 took to the skies with talented pilot John Derry DFC at the controls. Derry had flown Hawker Typhoons during the war and was recruited as a permanent test pilot from October 1947.

Flying a modified DH108 on 8 September 1948, he became the first British pilot to break the Sound Barrier, doing so in a shallow dive from 40,000ft.