Air crash investigation of American Airlines Flight 427

After the air crash, the investigators were shocked to find that the crash mode of the accident flight was very similar to that of United Airlines Flight 585 three years ago: two planes suddenly lost control before landing; The way out of control is that the rudder suddenly loses control and deviates, as if it is stuck, but in a different direction. (Flight 585 is on the right and Flight 427 is on the left) The only difference is that when Flight 427 crashed, it was sunny and there was no airflow.

Because the plane crashed vertically, its rudder and black box were almost intact. Investigators took out the hydraulic device of the rudder for testing, but they couldn't find any signs that the device was stuck. As the weather was clear and there was no strong wind, the investigators turned their attention to the crew. According to the records of the black box, the co-pilot has been stepping on the pedal that controls the rudder since the plane crashed, so it was once suspected that the co-pilot deliberately crashed the passenger plane. However, the investigators were listening to the phone records, and there was no evidence that the co-pilot was different-he obviously wanted to save the plane, but the plane got out of control for unknown reasons.

Therefore, the investigation was once again deadlocked, and experts could not find the specific reasons for the two air crashes. If Flight 427 can't find the cause of the crash, I'm afraid more than 3,000 Boeing 737 passenger planes around the world will face the fate of grounding.

The breakthrough occurred on June 9th 1996. In the evening, another 737-2H5 passenger plane of Dongfeng Airlines Flight 5 17 had a similar accident, but the flight finally landed safely. Not only did no one die, but the plane was not damaged. Investigators analyzed the information provided by the captain and inspected the passenger plane that caused the accident. It took four and a half years to investigate the longest aviation accident in history.