David Warren - Inventor of the Black Box Flight Recorder
By Mike Hanlon
September 6, 2003
September 7, 2003 Behind many great inventions there is a tale of stubborn perseverance, clear foresight, lateral thinking and sometimes sheer coincidence that in the end brings benefit to many people. The story of "Black Box" flight recorder and its Australian inventor, Dr David Warren, is no exception. The "Black Box" is a device that records in-flight conversations and data. The term did not yet exist more than 50 years ago when Dr Warren first conceived the idea of recording the flight crew's conversation on a device that could be protected to increase its chances of surviving the crash.
Now a part of our everyday lexicon, "Black Box" recording technology is also beginning to be applied on a large scale in trains, trucks and automobiles.
Gizmo recently caught up with Dr Warren to learn the story behind the invention first-hand. Now in his early eighties, Dr Warren recalls with great detail the events leading up to his invention and the long, slow road to commercialisation that followed.
Despite having received very little monetary reward for conceiving what is now seen a worldwide necessity for aviation, Dr Warren speaks with satisfaction about his achievement and retains an open-minded approach towards new ideas and technology that we can all learn from.
Dr Warren cites several key inspirations for what was originally known as a "flight-recording device". Firstly, Australia's first major air calamity in 1934 claimed the life of David's father.
Dr Warren, then still at boarding school, had received a crystal set from his father just prior to the disaster that started his interest in amateur radio and electronics.
Almost 20 years later, when the age of commercial jet aircraft was in its infancy, Dr Warren worked in his capacity as a chemist specialising in aircraft fuels at the Aeronautical Research Laboratories where he found himself part of a "think-tank" investigating the possible causes of a recent Comet Jet Aircraft crash and prepare Australian infrastructure for commercial jet aircraft.
New fuels being used in Jets in the early 50's were more likely to become explosive at altitude than conventional aircraft fuels and this was identified as a possible cause of the Comet crash. This was the area of specific investigation for David - then still in his early 20's - but it was at this two-day meeting the he hit upon the idea of a flight recorder.
While listening to the arguments over possible causes of the crash, one of which was the new phenomenon of hijacking, Dr Warren realised that the solution could well be at hand if someone on the plane had been carrying a device similar to the then newly released Protona Minifon portable recorder that had caught his eye at a trade fair. Mention of the device to his superiors fell on deaf ears initially, but with support from colleagues and his own faith in the idea he continued to refine the idea in his own time.
The device would be fire proof (using steel wire as the recording medium like the "Pocket Recorder") and erase itself so that the last hours of the flight were always recorded.Dr Warren wrote the initial ground breaking report for ARL entitled "A Device for Assisting Investigation into Aircraft Accidents" in 1954.
Despite being published twice (including overseas), the report still failed to generate much interest and with further support form new Superintendent Tom Keeble, it was decided to take a "Show and Tell" approach by creating a prototype. After a series of tests the first "ARL Flight Memory Unit" was then produced.
The device consisted of a single steel wire as the recording medium and provided four hours of recording and automatically switched itself on and off with the aircraft. It was during this period that Dr Warren incorporated the idea of recording instruments on a separate channel - his interest in electronics as a schoolboy was brilliantly applied to turn instrument readings into recordable dots and bleeps.
Using this technique, the original unit was able to record data from 8 instruments every 2 seconds.The response was still less than encouraging with authorities still reluctant to accept the potential benefits of the device.
The project was given fresh impetus after David, who was working on the prototype during a lunchbreak) was given a brief introduction to the Secretary of the UK Air Registration Board, Sir Robert Hardingham in 1958. Hardingham immediately recognised potential of the flight memory device and David was put on a four day flight to England to demonstrate the invention. The flight (almost the only tangible reward Dr Warren has ever received for his invention) was an adventure in itself.
A detour through Africa eventuated in a historic recording of a lion hunt in Nairobi and the first ever "black box" recording on the last leg of the flight - chiefly because Dr Warren was nervous about the fact that one engine was out.
The recorder was well received in England (where the name "Black Box" was coined by a journalist at a briefing) and also in Canada where the idea was seen as a potential addition to beacons being developed there.
Dr Warren continued to lead the project, developing the Flight Memory device to record more instruments with greater accuracy. This led to the first commercially produced flight-recorder - the Red Egg - which was manufactured by British firm of S. Davall & Son and captured a large part of the British and overseas market at that time.
Following the crash of a Fokker Friendship plane in 1960 in Queensland, a judicial order required that all Australian airliners carry speech recorders. Australian authorities ignored the local talent and awarded the contract to USA company which caused delays in development and installation.
A further disaster at Wintoon in 1967 saw Australia became first country to make both flight data and cockpit voice mandatory on all turbo-props and jets.
Dr Warren is aware that support in the initial phase of his invention could have resulted in wider benefits to Australia and himself, but remains philosophical - the attitude he faced at the time was one of "if its any good the Americans would have it already" but Dr Warren takes satisfaction from the benefit the idea has wrought and believes that keeping an open mind will help us to avoid the mistakes made by his superiors in the past - "As you get older, you shouldn't loose the excitement of something new".