The Civil Aviation Administration of China (CAAC) has made a popularization - "black box" is the most important and direct evidence to judge the cause of the flight accident.

The official name of the "black box" is the flight information recording system, which includes two sets of instruments:

One is the cockpit voice recorder, which records all kinds of voices (including conversations, telegrams, and other kinds of sounds) in the cockpit from the beginning of the flight, but only retains the voices for 30 minutes before the recording stops. The sound is only retained for the 30 minutes before the recording stops.

The other is the flight data recorder, the aircraft on the various data instantly recorded on tape, now the "black box" can record up to 60 kinds of data, including the aircraft's acceleration, attitude, thrust, fuel, the position of the steering surface, and other important data, the record of the time range of the last 25 hours.

"

Black box" is not only in the aviation accident investigation. Normally, after an airplane has flown for a period of time, the playback records can also reproduce errors or malfunctions that have been detected in the airplane, making it easier for maintenance engineers to find the location of the malfunction.