What Are Black Boxes On An Aircraft And Why Are They Important?

Black box is a term used to call two separate pieces of equipment, a cockpit voice recorder (CVR) and a flight data recorder (FDR). Black box information storage devices are compulsory on all commercial and corporate flights. They are usually located in the aircraft’s tail, where they are more likely to survive a crash.

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Black box recorders help solve aircraft crashes. Photo: Getty Images

The idea to create a device to store flight data was born in Australia in the 1950s by Dr. David Warren. When Dr. Warren was six years old, his father was killed in a plane crash while flying from Tasmania to Melbourne across the Bass Strait. This incident got him to develop a unit that could record flight data and cockpit conversations to help investigators following a crash.

His invention was called the “ARL Flight Memory Unit,” and while it did not get too much attention, it began being built in the US and the UK several years later. Australia was the first country to make the technology compulsory until the United States followed in 1967, making it mandatory on all commercial aircraft.

Why is it called a “black box”?

The term “black box” was first used by the British during World War Two and referred to the secret development of radar and electronic navigational aids in British aircraft. These secretive devices were housed in non-reflective black boxes. Today, aircraft black boxes are painted in a color called international orange that aerospace and engineering firms use to help distinguish items from their surroundings. In other words, they stand out and are easy to locate visually.

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The FDR and VDR are typically located in the aircraft’s tail. Photo: SWA 4013 Recorders via Flickr

Meanwhile, the name “black box” is what most people refer to as aviation experts prefer to call them electronic flight data recorders. A flight data recorder’s job is to keep a detailed track of flight information such as position, altitude, speed, and cockpit conversations.

In modern aircraft, civil airliners have multiple devices to carry out these tasks so that all the information is available to investigators in the event of a crash.

FDRs emit a ping when submerged

These days, flight data recorders are encased in a strong, corrosion-resistant stainless steel or titanium and are wrapped in insulation that can withstand high temperatures. Modern FDRs also have an underwater locator beacon that emits an ultrasonic ping to help searchers find it. These beacons can work at a depth of up to 6,000 meters (20,000 ft) for 30 days.

As for the cockpit recordings, they work on a loop recording the last two hours of conversation between the crew and any other noises that can be heard from the cockpit.

Why is new technology not used?

Following the disappearance of Malaysia Airlines Flight 370 in 2014, there have been calls to develop a system that sends real-time flight information to a system on the ground. If such a system had been in place when flight 370 went missing from the radar screens, investigators would have known precisely where to search.

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Aircraft data could be streamed using satellites. Image: Thales

The technology to enable this has to be available today, but it might be the cost to airlines that inhibits its implementation.

Do you think flight recorders are using outdated technology and should be updated, or is it fine how it is? Please let us know your thoughts in the comments.