? The first reason: human factors. Man-made reasons are mainly pilots' disability, misjudgment and operational errors. Although the degree of automation of aircraft has been strengthened, many operations still need to be completed by pilots. Because modern civil aviation has given effective emergency measures for most foreseeable accidents, the possibility that accidents are caused by a single factor is very small. Therefore, most accidents are caused by the simultaneous occurrence of many small probability events. According to relevant statistics, about 50% of accidents are caused by pilot's operational errors. ?
The second reason: the plane itself. This aspect is mainly design defects, damage to important components and mechanical failures. In many cases, the damage of aircraft parts is an important factor in accidents, and the external environment will destroy aircraft parts. In addition, the design defects of the aircraft itself or the introduction of new technologies can also lead to accidents.
When an air crash occurs due to external factors, corresponding preventive and first-aid measures should also be taken. First of all, keep the most stable and safe posture: bend over, tuck your knees with your hands, put your head above your knees, stretch your feet forward and stick to the floor. Secondly, when there is smoke in the cabin, be sure to put your head in the lowest position, because the smoke is emitted upwards, hold your breath, cover your nose and mouth with a wet towel before breathing, and then bend over or crawl to the exit. If the plane crashes over the ocean, put on your life jacket immediately. ?