The Upside Down Under
The 'black' box Flight Recorder


The black box flight recorder has helped make commercial air travel the world's safest form of travel.

The Black Box flight recorder was invented by Australian scientist Dr David Warren, who lost his own father to an aircraft tragedy in 1934 when the Miss Hobart crashed into the Bass Strait.

This remarkable device is virtually indestructible and records the final moments of a crashed plane's last flight. While it is a box, it's not black - it's bright orange colour is called 'international orange', making it easier to find in crash-site rubble.

David Warren
David Warren

It was David Warren’s interest in the possibility of personally recording music that led to the invention of the world’s first flight recorder or ‘black box’.

David Warren was a research scientist at the Aeronautical Research Laboratory (ARL) in Melbourne. In the mid-1950’s he was involved in the accident investigations related to the mysterious crash of the world’s first jet-powered commercial aircraft, the Comet. It occurred to Dave that it would be extremely useful if there had been a recording of what had happened in the aeroplane immediately prior to the crash. David then recalled the world’s first miniature recorder that he had recently seen at a trade fair. Suddenly he could visualise such a recorder placed in all aircraft, continually recording details and able to be recovered after a crash.

Black Box Mk 1 (1958)
Mk 1 (1958) recording system

As with many new concepts, especially in Australia, David had trouble getting his idea off the ground. Eventually David prepared a report that was circulated internationally but produced little interest. David drew on his early work experience as a teacher, remembering ‘show and tell’ was more effective than just ‘tell’. He decided, in his own time, to build a demonstration recorder. Thus the first ‘black box’ was born. It could continually store up to four hours of speech, prior to any accident, as well as flight instrument readings. But, still no interest from any authorities.

Black Box Mk2 (1962)

It was 1958, during an informal visit to ARL by Sir Robert Hardingham, the former British air Vice-Marshal, that the breakthrough occurred. David Warren was asked, during his lunchtime, to demonstrate his ‘unofficial project’. Straightaway Sir Robert saw the potential. David and his black box were almost immediately on a flight to England. The reception there was most encouraging. The Ministry of Aviation announced that the installation of the black box flight recorder for instrument readings might soon be made mandatory. The black box was also successfully demonstrated in Canada. In America the authorities declined an invitation from the Australian Embassy to demonstrate the device.

Video: Dr David Warren gives an early report on his invention of the flight recorder

Back in Australia, plans were made for further development and production. However, a continuing lack of Australian support meant that, as the idea finally took off around the world, companies in other countries moved ahead with development, capturing the growing market.

It was only after the crash of a Fokker Friendship at Mackay (Queensland) in 1960 that the inquiry judge strongly recommended that black box flight recorders be installed in all airliners. Australia then became the first country in the world to make cockpit-voice recording compulsory.

Fokker Friendship Memorial - Mackay, Queensland

Since that time, David Warren’s invention, the black box flight recorder, has been universally adopted as a means to investigate accidents and to prevent their recurrence. The black box flight recorder has more than proved itself with its significant contribution to international airline safety.

Dr. Warren was recognized by the ICAO Council and the international civil aviation community for the outstanding contributions to aviation safety – made possible by his invention and refinement of the first-ever aircraft flight recorder, or black box.

Dr David Warren
Black box inventor Dr. David Warren named 2016 ICAO Edward Warner Award recipient

The award ceremony took place on the opening day of ICAO’s 39th triennial Assembly, with hundreds of international dignitaries on hand to see President Aliu present the award to three of Dr. Warren’s children.

“Flight recorders are one of our most relied upon resources for the improvement of aviation safety,” President Aliu highlighted,

“and I wish to acknowledge here the tremendous debt of gratitude owed to Dr. Warren’s vision, commitment and tenacity, and for his far reaching contributions to international civil aviation.”

Why is it called a 'black' box when it is orange?

Why the orange flight box recorder came to be called the Black Box is somewhat of a mystery.

The orange 'black' box Flight Recorder
The orange 'black' box Flight Recorder

Dr Warren referred to his invention as the "ARL Flight Memory system". The term "black box" was believed to have been attributed to a journalist. In the early days black box was in common usage for such things as a mystery box of electronics for which the main interest was in what goes in and what comes out rather than what is inside the box and how it works.

Here are just a few of the theories as to why the Flight Data Recorders are called Black Boxes...

  • Early designs being perfectly dark inside
  • The boxes are black after being 'charred' in an aircraft accident
  • Early boxes having electronic items are often refereed as black box
  • The first recorders were black and white photographic based
  • In science, computing, and engineering, a black box is a device, system or object which can be viewed in terms of its input, output (or transfer characteristics) without any knowledge of its internal workings. (see below)


Black Box testing diagram

  • And so the list goes on...

Anyway, whatever the reason, the term 'Black Box' has now become the accepted term recognized by the general public for accident recorders even though, for aircraft, a readily distinguishable orange colour is standard.

How does the Black Box work?

Whereas the data and voices are recorded from the cockpit, the recorders are not placed inside the cockpit. Usually they are placed in the tail-end of the aircraft, where the structure of the aircraft protects them best in case of a crash.

Location of Black Box Flight Recorder
Location of Black Box Flight Recorder

Flight recorders actually consist of two functional devices, the flight data recorder (FDR) and the cockpit voice recorder (CVR), though sometimes these two devices are packaged together in one combined unit.

The FDR records many variables, not only basic aircraft conditions such as airspeed, altitude, heading, vertical acceleration, and pitch but hundreds of individual instrument readings and internal environmental conditions.

The CVR records verbal communication between crew members within the aircraft’s cockpit as well as voice transmissions by radio. Aircraft sounds audible in the cockpit are also caught on the recorder. Flight recorders are commonly carried in the tail of the aircraft, which is usually the structure that is subject to the least impact in the event of a crash. In spite of the popular name black box, flight recorders are painted a highly visible vermilion colour known as “international orange.”

The voice and instrument data processed by the flight recorder are stored in digital format on solid-state memory boards. Up to 2 hours of cockpit sound and 25 hours of flight data are stored, new data continuously replacing the old.

The memory boards are housed within a box or cylinder called the crash-survivable memory unit. This is the only truly survivable component of the flight recorder (the other components, such as the data processor, are not necessary for retrieval of data). Consisting of a heavy stainless steel shell wrapped within layers of insulating material and covered by an aluminum housing, a memory unit is expected to survive impacts of 3,400 g (units of gravitational acceleration), flame temperatures as high as 1,100 °C (2,000 °F), and pressures encountered at 6,000 metres (20,000 feet) underwater.

Black Box Flight Recorder inner workings
Black Box Flight Recorder inner workings

In the event of a crash at sea, flight recorders are equipped with a sonar device that is designed to emit an ultrasonic locator signal for at least 30 days.


Black box inventor Dr. David Warren named 2016 ICAO Edward Warner Award recipient

Add comment

Leave a Reply

Subscribe to my blog:

Follow Me on Social Media

Click on the icons below to follow
me on your favourite social platform...

Translate Site

Blog Stats

  • 11,642 Post Visits

Your Header Sidebar area is currently empty. Hurry up and add some widgets.

Back to Top
%d bloggers like this: