When a plane crash occurs the most important part that is recovered is the so-called "black box" or Flight recorder. There are two of these in each aircraft, with a special recorder in each box.
One of the recorders is responsible for retaining flight data, providing a record of the movements of key instruments, such as wind speed and altitude indicators, and the position of the rudders and spoilers. The information, in the form of electronic pulses, is recorded on a tape. In this flight data recorder (logbook) up to 200 flight hours are recorded. This black box is located at the rear of the aircraft.
The other box contains the cockpit voice recorder, which records the crew's conversations and sounds. It works with a continuous tape that lasts 30 minutes (although the latest digital models record up to 120 minutes), so that the last half hour is recorded. This black box is located at the top of the cockpit.
The boxes that protect these recorders consist of two stainless steel plates, between which there is material that allows them to withstand temperatures of more than 1,000 degrees Celsius for half an hour.
Despite its name, the black box is not dark but a phosphorescent orange, easier to see in the rubble of an air disaster.
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