David Ronald de Mey Warren left a lasting legacy for the aviation industry through his idea for a machine that would record the voices and instrument readings in the cockpit of an aeroplane. The modern-day equivalent of his device is now installed in aircraft around the world.
David Warren was born at a remote mission station on Groote Eylandt in the Gulf of Carpentaria in 1925. At the age of four, he was sent to boarding school at Launceston Grammar, Tasmania, and Trinity Grammar in Sydney. When Warren was nine years old, his father died when a De Havilland plane, the ‘Miss Hobart’, travelling from Launceston to Melbourne was lost over Bass Strait. There were no survivors and no clues as to why the plane went down.
Warren graduated from the University of Sydney with a Bachelor of Science. While studying at the university in the 1940s, Warren met Ruth Meadows, who became his wife and lifetime supporter. Together, they raised a family and shared an interest in science and education. After completing his degree, Warren worked as a teacher and as a lecturer in chemistry and in 1948 he was appointed as Scientific Officer chemist at Woomera Rocket Range in South Australia. His research into rocket fuel took him to Imperial College London in 1949, where he took a PhD in chemical engineering.
Two years later he began work as a scientist at the Aeronautical Research Laboratory in Melbourne. In 1953, he was involved in the accident investigations into the crash of the world’s first jetliner, a de Havilland DH 106 Comet. Before the accident, he had seen a miniature tape recorder, the ‘Minifon’, at a trade show. During the investigation, Warren put forward the idea of a cockpit voice recorder as a means of solving otherwise unexplainable aircraft accidents. While at the time there were devices which recorded some flight parameters, they were not reusable and did not include voice recording.
His idea initially raised little interest, so Warren spent the next several years developing the technology. He designed and constructed the world’s first flight data recorder prototype at the Aeronautical Research Laboratory in 1956. It was named the “ARL Flight Memory Unit”. The device could continually store up to four hours of speech, prior to any accident, as well as flight instrument readings. It relied on magnetic recording media, which allowed easy erasing and re-recording, making it practical for routine line service. The recorder became known as the ‘black box’.
It took several years before the value of the idea was accepted. In 1958, the Secretary of the United Kingdom Air Registration Board, while visiting the Melbourne Laboratory, saw the Flight Memory Unit. He arranged for Warren to take his machine to England and demonstrate it.
Back in Australia, the judge at the Court of Inquiry into the unexplained crash of a Fokker Friendship plane in Mackay, Queensland, in 1960, ordered that cockpit voice and flight data recorders be fitted to all future Australian aircraft.
Warren was given a team, comprising Kenneth Fraser, Lane Sear and Walter Boswell, to update the early Flight Memory Unit to a standard that would demonstrate its true potential. A cockpit voice/ flight data recording and ground recovery system (with the magnetic recorder housed in a crash and fire proof box) was subsequently flight tested with full voice and data recovery.
Australia was the first country to make cockpit voice and flight data recording mandatory for accident investigation purposes, but others soon followed and now, every airline in the world has “black boxes” fitted to their aircraft. The technology is also used in other forms of transport to capture information in the lead-up to accidents.
From 1952 to 1983, Warren held the position of Principal Research Scientist at the Aeronautical Research Laboratories, Melbourne, now part of the Defence Science and Technology Organisation. He was also the Scientific Advisor to the Victorian State Parliament in 1981-82.
In 2002, Dr David Warren was made an Officer in the Order of Australia in the Australia Day Honours for his services to the aviation industry, particularly through the early conceptual work and prototype development of the black box flight data recorder. In November 2008, Qantas named one of its Airbus A380s after him in honour of his services to aviation.
Dr David Warren died on 19 July 2010, aged 85, in Melbourne. He was buried in a casket bearing the label “Flight Recorder Inventor; Do Not Open”.