American Airlines Flight 587 'Disaster over New York'
American Airlines Flight 587 was a regularly scheduled passenger flight
from John F. Kennedy International Airport in New York City to Santo
Domingo's Las Américas International Airport in the Dominican Republic.
On November 12, 2001, the Airbus A300-600 flying the route crashed into
the Belle Harbor neighborhood of Queens, a borough of New York City,
shortly after takeoff. All 260 people on board the flight were killed,
along with five people on the ground. It is the second-deadliest
aviation incident involving an Airbus A300, after Iran Air Flight 655
and the second-deadliest aviation incident to occur on U.S. soil, after
American Airlines Flight 191. To date, no single-airplane crash incident
that was ruled accidental and not criminal since then has surpassed
that death toll, though before 2001 there had been deadlier incidents of
this type.
The location of the accident and the fact that it took place two months and one day after the September 11 attacks on the World Trade Center in Manhattan initially spawned fears of another terrorist attack. However, terrorism was officially ruled out as the cause by the National Transportation Safety Board, which instead attributed the disaster to the first officer's overuse of rudder controls in response to wake turbulence or jet wash from a Japan Airlines Boeing 747-400 that took off minutes before it. According to the NTSB, this aggressive use of the rudder controls by the co-pilot caused the vertical stabilizer to snap off the plane. The plane's two engines also separated from the aircraft before it hit the ground.
The A300-600 took off immediately after a Japan Airlines Boeing 747-400 on the same runway. It flew into the larger jet's wake, an area of turbulent air. The first officer attempted to stabilize the aircraft with alternating aggressive rudder inputs. The strength of the air flowing against the moving rudder stressed the aircraft's vertical stabilizer, and eventually snapped it off entirely, causing the aircraft to lose control and crash. The National Transportation Safety Board (NTSB) concluded that the enormous stress on the rudder was due to the first officer's "unnecessary and excessive" rudder inputs, and not the wake turbulence caused by the 747. The NTSB further stated "if the first officer had stopped making additional inputs, the aircraft would have stabilized". Contributing to these rudder pedal inputs were characteristics of the Airbus A300-600 sensitive rudder system design and elements of the American Airlines Advanced Aircraft Maneuvering Training Program.
The manner in which the vertical stabilizer separated concerned investigators. The vertical stabilizer is connected to the fuselage with six attaching points. Each point has two sets of attachment lugs, one made of composite material, another of aluminum, all connected by a titanium bolt; damage analysis showed that the bolts and aluminum lugs were intact, but not the composite lugs. This, coupled with two events earlier in the life of the aircraft, namely delamination in part of the vertical stabilizer prior to its delivery from Airbus's Toulouse factory, and an encounter with heavy turbulence in 1994, caused investigators to examine the use of composites. The possibility that the composite materials might not be as strong as previously supposed was a cause of concern because they are used in other areas of the plane, including the engine mounting and the wings. Tests carried out on the vertical stabilizers from the accident aircraft, and from another similar aircraft, found that the strength of the composite material had not been compromised, and the NTSB concluded that the material had failed because it had been stressed beyond its design limit, despite ten previous recorded incidents where A300 tail fins had been stressed beyond their design limitation in which none resulted in the separation of the vertical stabilizer in-flight.
The official NTSB report of October 26, 2004, stated that the cause of the crash was the overuse of the rudder to counter wake turbulence.
The crash was witnessed by hundreds of people, 349 of whom gave accounts of what they saw to the NTSB. About half (52%) reported a fire or explosion before the plane hit the ground. Others stated that they saw a wing detach from the aircraft, when in fact it was the vertical stabilizer. Some witnesses reported seeing one of the engines burst into flames and break off the plane, and others reported hearing a loud sound like a sonic boom.
After the crash, Floyd Bennett Field's empty hangars were used as a makeshift morgue for the identification of crash victims.
The location of the accident and the fact that it took place two months and one day after the September 11 attacks on the World Trade Center in Manhattan initially spawned fears of another terrorist attack. However, terrorism was officially ruled out as the cause by the National Transportation Safety Board, which instead attributed the disaster to the first officer's overuse of rudder controls in response to wake turbulence or jet wash from a Japan Airlines Boeing 747-400 that took off minutes before it. According to the NTSB, this aggressive use of the rudder controls by the co-pilot caused the vertical stabilizer to snap off the plane. The plane's two engines also separated from the aircraft before it hit the ground.
The A300-600 took off immediately after a Japan Airlines Boeing 747-400 on the same runway. It flew into the larger jet's wake, an area of turbulent air. The first officer attempted to stabilize the aircraft with alternating aggressive rudder inputs. The strength of the air flowing against the moving rudder stressed the aircraft's vertical stabilizer, and eventually snapped it off entirely, causing the aircraft to lose control and crash. The National Transportation Safety Board (NTSB) concluded that the enormous stress on the rudder was due to the first officer's "unnecessary and excessive" rudder inputs, and not the wake turbulence caused by the 747. The NTSB further stated "if the first officer had stopped making additional inputs, the aircraft would have stabilized". Contributing to these rudder pedal inputs were characteristics of the Airbus A300-600 sensitive rudder system design and elements of the American Airlines Advanced Aircraft Maneuvering Training Program.
The manner in which the vertical stabilizer separated concerned investigators. The vertical stabilizer is connected to the fuselage with six attaching points. Each point has two sets of attachment lugs, one made of composite material, another of aluminum, all connected by a titanium bolt; damage analysis showed that the bolts and aluminum lugs were intact, but not the composite lugs. This, coupled with two events earlier in the life of the aircraft, namely delamination in part of the vertical stabilizer prior to its delivery from Airbus's Toulouse factory, and an encounter with heavy turbulence in 1994, caused investigators to examine the use of composites. The possibility that the composite materials might not be as strong as previously supposed was a cause of concern because they are used in other areas of the plane, including the engine mounting and the wings. Tests carried out on the vertical stabilizers from the accident aircraft, and from another similar aircraft, found that the strength of the composite material had not been compromised, and the NTSB concluded that the material had failed because it had been stressed beyond its design limit, despite ten previous recorded incidents where A300 tail fins had been stressed beyond their design limitation in which none resulted in the separation of the vertical stabilizer in-flight.
The official NTSB report of October 26, 2004, stated that the cause of the crash was the overuse of the rudder to counter wake turbulence.
The crash was witnessed by hundreds of people, 349 of whom gave accounts of what they saw to the NTSB. About half (52%) reported a fire or explosion before the plane hit the ground. Others stated that they saw a wing detach from the aircraft, when in fact it was the vertical stabilizer. Some witnesses reported seeing one of the engines burst into flames and break off the plane, and others reported hearing a loud sound like a sonic boom.
After the crash, Floyd Bennett Field's empty hangars were used as a makeshift morgue for the identification of crash victims.
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