Squadron leader Squadron leader (Sqn Ldr or S/L) is a senior officer rank used by some air forces, with origins from the Royal Air Force. The rank is used by air forces of many countries that have historical British influence. Squadron leader is immediatel ...

John Douglas Derry DFC (5 December 1921 – 6 September 1952) was a British

test pilot A test pilot is an aircraft pilot with additional training to fly and evaluate experimental, newly produced and modified aircraft with specific maneuvers, known as flight test techniques.Stinton, Darrol. ''Flying Qualities and Flight Testin ...

who is believed to be the first Briton to have exceeded the

speed of sound The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elasticity (solid mechanics), elastic medium. More simply, the speed of sound is how fast vibrations travel. At , the speed of sound in a ...

in flight.

Early life and education

Derry was born in

Cairo Cairo ( ; , ) is the Capital city, capital and largest city of Egypt and the Cairo Governorate, being home to more than 10 million people. It is also part of the List of urban agglomerations in Africa, largest urban agglomeration in Africa, L ...

Egypt Egypt ( , ), officially the Arab Republic of Egypt, is a country spanning the Northeast Africa, northeast corner of Africa and Western Asia, southwest corner of Asia via the Sinai Peninsula. It is bordered by the Mediterranean Sea to northe ...

, where his father, Douglas Derry, was Professor of Anatomy at Royal Egyptian University. Douglas Derry was the first anatomist to be involved in the examination of Tutankhamun's mummy, after the discovery of the tomb in 1925. John Derry attended Dragon School in

Oxford Oxford () is a City status in the United Kingdom, cathedral city and non-metropolitan district in Oxfordshire, England, of which it is the county town. The city is home to the University of Oxford, the List of oldest universities in continuou ...

and

Charterhouse School Charterhouse is a Public school (United Kingdom), public school (English independent boarding school for pupils aged 13–18) in Godalming, Surrey, England. Founded by Thomas Sutton in 1611 on the site of the old Carthusian monastery in Charter ...

. In his youth, Derry developed a keen interest in bird watching and often attended motor races.

Military career

Shortly after the outbreak of

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

, he left school to enlist as a wireless operator and air gunner in the

Royal Air Force The Royal Air Force (RAF) is the Air force, air and space force of the United Kingdom, British Overseas Territories and Crown Dependencies. It was formed towards the end of the World War I, First World War on 1 April 1918, on the merger of t ...

. In 1942 he received a commission and the following year trained (in

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

) as a pilot. His operational career began late in 1944 when he joined 182 Squadron, flying

Hawker Typhoon The Hawker Typhoon was a British single-seat fighter-bomber, produced by Hawker Aircraft. It was intended to be a medium-high altitude interceptor aircraft, interceptor, as a replacement for the Hawker Hurricane, but several design problems we ...

s on close support to the Allied armies in the

Low Countries The Low Countries (; ), historically also known as the Netherlands (), is a coastal lowland region in Northwestern Europe forming the lower Drainage basin, basin of the Rhine–Meuse–Scheldt delta and consisting today of the three modern "Bene ...

. After serving also with 181 Squadron, he was given command of 182 Squadron shortly before the end of the war.

Test pilot career

In 1947 Derry joined

de Havilland The de Havilland Aircraft Company Limited (pronounced , ) was a British aviation manufacturer established in late 1920 by Geoffrey de Havilland at Stag Lane Aerodrome Edgware on the outskirts of North London. Operations were later moved to ...

as a test pilot, working largely on the de Havilland DH 108 aircraft. He is widely believed to have exceeded the speed of sound on 6 September 1948, when he lost control of his aircraft and the Mach meter supposedly 'briefly showed' supersonic speeds in a shallow dive from 12,195 m (40,000 ft) to 9,145 m (30,000 ft). Despite lack of substantial evidence (the recording apparatus was switched off during the flight), the news was promoted by the British press as having broken the sound barrier. Also in 1948, he was awarded the Gold Medal of the

Royal Aero Club The Royal Aero Club (RAeC) is the national co-ordinating body for air sport in the United Kingdom. It was founded in 1901 as the Aero Club of Great Britain, being granted the title of the "Royal Aero Club" in 1910. History The Aero Club was foun ...

Tom Wolfe Thomas Kennerly Wolfe Jr. (March 2, 1930 – May 14, 2018)Some sources say 1931; ''The New York Times'' and Reuters both initially reported 1931 in their obituaries before changing to 1930. See and was an American author and journalist widely ...

's book '' The Right Stuff'' mentioned this claim, but referred to another test pilot, Geoffrey de Havilland Jr., who had been killed in a previous test flight, when his DH 108 broke up at about Mach 0.9. As a demonstration pilot, Derry developed a new type of

aerobatic manoeuvre Aerobatic maneuvers are flight paths putting aircraft in unusual attitudes, in air shows, dogfights or competition aerobatics. Aerobatics can be performed by a single aircraft or in formation with several others. Nearly all aircraft are capab ...

which became known as the "Derry Turn". It consists of a reversal of

bank A bank is a financial institution that accepts Deposit account, deposits from the public and creates a demand deposit while simultaneously making loans. Lending activities can be directly performed by the bank or indirectly through capital m ...

during a steep turn which is performed with the aircraft passing through the inverted rather than upright attitude.

Death

Derry was killed in the 1952 Farnborough Airshow DH.110 crash (the DH 110 went on to become the

de Havilland Sea Vixen The de Havilland DH.110 Sea Vixen is a British twin-engine, twin boom-tailed, two-seat, carrier-based fleet air-defence fighter flown by the Royal Navy's Fleet Air Arm from the 1950s to the early 1970s. The Sea Vixen was designed by the de Havi ...

) when his aircraft broke up because of a design fault resulting in catastrophic structural failure, with 31 fatalities including himself, his flight observer Tony Richards, and 29 spectators. The jury at the inquest returned a verdict that the pilot and observer died of accidental death and the deaths of the spectators were also accidental.

In popular culture

Derry's DH 108 historic test flight was used in dramatized form in the 1952 film '' The Sound Barrier'' directed by

David Lean Sir David Lean (25 March 190816 April 1991) was an English film director, producer, screenwriter, and editor, widely considered one of the most important figures of Cinema of the United Kingdom, British cinema. He directed the large-scale epi ...

. John Justin plays Philip Peel, a test pilot who brings his plane through the sound barrier and out of the speed-creating dive by the untried technique of applying reverse direction to the

control column A yoke, alternatively known as a control wheel or a control column, is a device used for Pilot (aeronautics), piloting some fixed-wing aircraft.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 563. Aviation Supplies ...

Chuck Yeager Brigadier general (United States), Brigadier General Charles Elwood Yeager ( , February 13, 1923December 7, 2020) was a United States Air Force officer, flying ace, and record-setting test pilot who in October 1947 became the first pilot in his ...

's comment on that filmic presentation: "Anyone who reversed the controls going transonic would be dead."

Early life and education

Military career

Test pilot career

Death

In popular culture

References

Further reading