The "black box" is one of the electronic recording devices dedicated to aircraft, called an aviation flight recorder. It contains a flight data recorder and a cabin voice recorder, and each mechanical part and electronic instrumentation of the aircraft is equipped with sensors connected to it. It can record the relevant technical parameters and the sounds in the cockpit half an hour before the aircraft stops working or crashes. When necessary, the recorded parameters can be played back for flight experiments and accident analysis. The black box has extremely strong resistance to fire, pressure, shock and vibration, resistance to seawater (or kerosene) immersion, and resistance to magnetic interference. Even if the aircraft is completely damaged, the recorded data in the black box can still be preserved intact. The causes of all air crashes in the world are found through black boxes. ————Reposted from Du Niang.
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