(1) Although a large number of new technologies have been adopted and many safety precautions have been taken, it is still difficult to crash unexpectedly. When an air crash happens, people always try their best to find the black box and analyze the cause of the accident.
It' s actually a black box. The reason why orange-red is used is mainly to distinguish it from the surrounding landforms and facilitate its search. It is a streamlined container made of special solid materials. Black box is an airborne information storage, that is, a tape recorder, which records important parameters in flight, such as relative ground state, speed, altitude, heading, speed, fuel and so on. According to these parameters, it is easy to draw the trajectory. Information is recorded and cleaned, but the flight information hours before the plane crash is retained.
(3) In addition to the orange appearance, in order to find it more easily, the black box is also equipped with a wireless beacon. This device can automatically and regularly transmit certain radio signals to the outside, which is convenient for the special receiver to receive.
(4) The black box shell is very strong, and the surface is covered with heat insulation materials. Can bear the impact of 3.4 kg objects from three directions for 5 minutes at the same time; Can withstand the impact of a 230 kg weight falling from a height of 3 meters; It can prevent fire and explosion, and can burn in the fire of 1 100℃ for half an hour; Can be soaked in 3 meters deep water for 30 days.
⑤ In order to ensure that the black box can work normally, like all aerospace designs, it has a high degree of "self-protection" and "mutual protection" in terms of working procedures and fault consideration. It's like the rules and regulations of entering a bank vault, with the aim of being foolproof.
For example, the power supply of the black box is very special. Under normal circumstances, the direct current required by the black box is provided by the power generation system of the aircraft. This kind of generator is an AC -DC converter, which directly converts alternating current from DC motor into direct current. Once the generator fails, it will automatically switch to the battery to provide the required voltage.
⑦ For example, the working switch of the black box should be turned on before the plane starts, but it doesn't matter even if the pilot forgets. When the plane taxies to a certain speed on the runway, the landing gear automatically retracts, and the working switch of the black box automatically opens due to the pressure of the landing gear strut.
The black box being developed a few days ago will tend to be computerized. This kind of electronic equipment is installed in a protective box, which consists of three main parts: an interface card for collecting data, a memory and a program for programming information into the memory. Compared with the traditional black box, it has great advantages. For example, the recording speed of parameters can be changed, and the recording speed will be automatically accelerated when there is abnormality, so that people can analyze it more accurately. In addition, its volume will be greatly reduced.