The mystery of the strangest plane crash in aviation history
The sound has been described as “psssssss”, like the noise a soft drink bottle can make when one pops the cap off. When experts first heard the sound, they thought it was a startled pilot and a sudden inhalation.
Dozens of investigators, pilots and technicians have listened to the recording thousands of times. All they know for certain is that it happened in the cockpit of USAir Flight 427 on September 8, 1994, exactly 24 seconds before the Boeing 737 plunged down a hillside near Pittsburgh, Pennsylvania. , killing 132 people.
That “psssssss” sound, mixed with a series of sounds like thumps, bumps and clicks, was picked up by the plane’s cockpit voice recorder. Those sounds – some explained, some unexplained – could be the clues for experts to find answers to the plane crash that has become the world’s biggest aviation mystery.
Despite 14 months of expeditious work, investigators were unable to figure out what went wrong with the plane’s control systems and why, what the pilots did, and what external influences may have contributed. caused the accident.
The question may never be answered. USAir Flight 427 that year became the second fatal Boeing 737 crash, and it left investigators wondering if there was something lurking in the plane that they didn’t understand. , is there something that could cause disaster again?
Terrifying moment and haunting scene
The Boeing 737, carrying 127 passengers and 5 crew members (132 people in total), departing from Chicago’s O’Hare International Airport, is expected to land at Pittsburg International Airport at 7:15′. However, it did not land safely.
At around 7 a.m., or about 15 minutes before landing, co-pilot Charles Emmett and captain Peter Germanao chatted in the cockpit about the still bright sun and how they were going to handle it, as well as air traffic. Crowd around Pittsburg airport will slow down the flight.
The scene of the 1994 plane crash.
The funny jokes of the two pilots of the plane were quickly replaced by loud screams and then panic spread. The plane suddenly veered to the left, flipped upside down, and began to spiral down from the sky.
In 23 seconds of horror, the massive plane plummeted to the ground from an altitude of more than 1,800m, at a speed of 500km / h. The plane crashed at a site near Green Garden Plaza in Hopewell, just a few kilometers from the airport, and broke into pieces. In the blink of an eye, 132 people on board the plane lost their lives.
Witnesses said they witnessed a horrifying scene at the scene of the plane crash. Scenes of arms and legs dangling from the tree, splashes of blood. Everyone who went to the plane crash site that night and the next morning had to be vaccinated against hepatitis to prevent contact with infected blood.
The New York Times that year quoted Hopewell police chief, Mr. Freedy David, that: “It was a horrible scene. Body pieces, pieces of seats, luggage were scattered up to 200m. The biggest piece of plane I’ve seen is as small as a car door.”
Debris collected from the scene.
When they began to clean up the scene, authorities found that there was too much debris and the victims’ bodies and they thought the work would take weeks. US officials at the time said there were bodies that could never be identified.
5 years for the answer makes the pain worse
But the tape recorder – the “rudimentary” version of the time – did not provide answers to two key questions: Did the rudder really move? If so, was it moved due to some glitch or was it because the pilot pushed the pedals in the cockpit?
Many other questions – including information about the pilots’ efforts to control the situation – could be answered if the ship was equipped with a more advanced voice recorder.
The rudder on a Boeing 737 is much more complicated than the rudder on other Boeing planes. It is capable of moving on its own without pilot control, but flying completely off course without the pilot’s permission is unheard of. The rest of the rudder control system on the crashed Flight 427 showed no obvious signs of malfunction.
Most of the unsolicited movement involved the rudder’s hidden damper, a system that automatically adjusts the rudder to prevent the aircraft from swerving in turbulence or when about to turn.
The damper does have mechanical stops, however, and pilots have been trained to recognize the usual malfunction and simply turn it off.
To date, the 737 rudder has become the most studied aircraft control system in history. Boeing’s safety team and a special “critical design review team” from the US Federal Aviation Administration (FAA) have carried out thousands of hours of testing and suggested improvements. But they found nothing that could explain the crash of Flight 427.
It took five years for the National Transportation Safety Board (NTSB) to determine what caused the plane to crash. This is the longest investigation in the history of the NTSB. The lengthy investigation deepened the grief of the victim’s family and raised many questions about the most popular airline at the time.
According to the Pittsburg Gazette, on March 24, 1999, the NTSB issued its final report, stating that the cause of the crash of Flight 427 in the middle of the clear sky was due to a problem with the rudder.
Source: Compilation
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