The Black Box

As our thoughts turn to the sad news of the fate of MH370, the next piece of this puzzling jigsaw is to find the assumed crash site, which is being closed in on.  Over 120 pieces of Debris have been spotted via satellite and the radius of the potential crash site has been narrowed to 50,000 square miles.  This is a huge unprecedented task given the size of the area.  Once the location is pinpointed the next task is to find then the black box, which may give some answers to this mystery and hopefully some answers for the grieving families.   Experts and a towed pinger locator are due to arrive in Perth on the 28th March. We took a look at the black box and its importance in aviation incidents, in scenarios with little clues it can sometimes be the only source of answers as in the case of Air France 447.  (The Air France Black Box took two years to locate)



Any commercial airplane or corporate jet is required to be equipped with a cockpit voice recorder and a flight data recorder. It is these two items of separate equipment, which we commonly refer to as a ‘Black Box.’  These pieces of equipment are vitally important should the plane crash, as they help crash investigators find out what happened just before the crash.

To help locate the cockpit voice recorder and a flight data recorder in the aftermath of a plane crash that occurs at sea, each recorder has a device fitted to it known as an Underwater Locator Beacon (ULB). The device is activated as soon as the recorder comes into contact with water and it can transmit from a depth as deep as 14,000 feet. Also, to help investigators find them; a Black Box is not actually black at all, but bright orange.

All recorders undergo countless tests. For example, one Black Box recorder, the L-3 FA 2100 underwent testing that includes exposure to a 1,110°C fire for an hour and 260°C heat for 10 hours. It is also able to operate between -55° to +70°C and it can carries a minimum 25 hours of flight data.


 The Black Box was first invented by a young Australian scientist named Dr. David Warren. While Warren was working at the Aeronautical Research Laboratory in Melbourne in the mid-1950s he was involved in the accident investigation surrounding the mysterious crash of the world’s first jet-powered commercial aircraft, the Comet. Realising that it would have been useful for investigators if there had been a recording of what had happened on the plane just before the crash, he got to work on a basic flight data recorder. The first demonstration unit was produced in 1957, but it was not until 1960, after an unexplained plane crash in Queensland, that Australia became the first country in the world to make the Black Box mandatory for all commercial aircraft.


The main purpose of the Cockpit Voice Recorder is to record what the crew say and monitor any sounds that occur within the cockpit. While investigators might be interested in any witty banter between pilots that went on just before an explosion or plane malfunction, trained investigators are keen to pick up on sounds such as engine noise, stall warnings or emergency pings and pops. Investigators are so skilled that they are then able to work out crucial flight information such as the speed the plane was travelling and engine rpm and can sometimes pinpoint the cause of a crash from the very sounds the plane was making before it crashed. The Cockpit Voice Recorder is also extremely important for determining the timing of events as it contains information such as communication between the crew and ground control and other aircraft. The Cockpit Voice Recorder is usually located in the tail of a plane.


Of equal, if not more significance to the Cockpit Voice Recorder, is the Flight Data Recorder. This piece of equipment is essential to the work of Air Crash Investigators as it records the many different operating functions of a plane all at once, such as the time, altitude, airspeed and direction the plane is heading. But these are just the primary functions of the recorder, in fact, modern Flight Data Recorders are able to monitor countless other actions undertaken by the plane, such as the movement of individual flaps on the wings, auto-pilot and fuel gauge. Information stored in the Flight Data Recorder of a plane that has crashed is invaluable for investigators in their search for determining what caused a specific crash. The data stored on the recorders helps Air Crash Investigators generate computer video reconstructions of a flight, so that they can visualise how a plane was handling shortly before a crash.

The Flight Data Recorder and the Cockpit Voice Recorder are invaluable tools for Air Crash Investigators worldwide and will continue to play a major role in finding out the causes of aviation accidents, as well as offering plane manufacturers and government’s considerable ideas to help make air travel as safe as possible.

Sources NATGEO and Graphic News.

photo credit: <a href=”″>Boeing 777-200</a> via <a href=””>photopin</a&gt; <a href=””>(license)</a&gt;


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