David Warren of the Aeronautical Research Laboratories in Melbourne, Australia was involved in the accident investigations related to the mysterious crash of the world’s first jet-powered aircraft, the Comet, in 1953.

He argued that a cockpit voice recorder would be a useful means of solving otherwise unexplainable aircraft accidents. The idea initially raised little interest, so David decided to design and build an experimental unit to demonstrate the concept.

The unit could continually store up to four hours of speech, prior to any accident, as well as flight instrument readings. It took five years before the value and practicality of the idea was finally accepted internationally with the fits units going into production in 1957.

It took another five years before it became mandatory to fit cockpit recorders in Australian aircraft, Warren’s homeland. The modern-day equivalent of Warren’s device is now installed in passenger airlines around the world as a mandatory requirement.