The mysterious black box

There is a story that is retold whenever a plane crash hits the headlines; if only the aircraft were made of the same material as the black box, then everybody would survive. The legendary invincibility of the famous box is familiar to most of us. Yet for such a well-known object, it is remarkably mysterious. How many of us know that the “black” box is in fact painted fluorescent orange?

“It was originally called a black box in the days when anything to do with electronics was new and strange” explains Pete Cook from a flight recorder manufacturer. “They are painted orange nowadays to make them more easily visible in the event of a crash”.

There are two kinds of black box; the flight data recorder (FDR) and the cockpit voice recorder (CVR). Both are normally stored at the rear of an aircraft, where the fuselage meets the upper tail fin – the part of planes that has the best survival record. The same principle applies to human passenger – you are safer at the back.

Despite their reputation, neither box is in fact indestuctible. However, they can withstand a temperature of 1,100°C for 30 minutes and 250° for 10 hours. They must also be able to survive an impact force of 3,500g – that is 3,500 times the force of gravity.

To take this kind of strain, flight recorders are encased in two thicknesses of titanium. Memory chips hold the flight data.

While FDRs make an electronic record of a plane’s mechanical performance, CVRs record the communication between the crew. “After a crash in water, they send out a sonar “ping” so that they can be found”, says Cook. But they are still only recovered in 80 per cent of accidents”.

Human Factor and Aviation Safety Problems

Safety, aviation and human factors are closely related. Hundreds of the most diverse examples and incidents which take place in the planet's airspace, in all their variety, are united by one single component: the human factor.

This combination of words, sometime successfully discovered, was initially used only by the most advanced specialists. Then by everybody: from the minister to the airport security man. From frequent repetition the true meaning of the expression has been rubbed away like the pollen on the wings of butterflies which are pulled about by unthinking lovers of natural flight.

Meanwhile, the human factor - that is, to put it bluntly, man and his psyche, his inner world - was, is and will be the fundamental driving force and guide in any technological and related processes in life.

Many of the cases are related directly to human factors in aviation. Some say human error is the primary factor in up to 80 to 90 percent of the cases. Historically, 70 percent of commercial jet accidents involved humans in one form or another. In the early years of aviation, technical defects were the main cause of accidents. But as reliability improved, the human factor became the main factor.

However, aviation accidents often involve more than one cause, such as system complexity, poor human-machine interface, inappropriate work organization, awkward work procedures, altered communication between pilot and controllers, or loss of situational awareness. We should not place blame on the human operator alone, but rather to a combination of factors in a highly complex context. And yet the main linking element in this list is the man.

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