American Airlines Flight 587 was a regularly scheduled international passenger flight from John F. Kennedy International Airport, New York City, to Las Américas International Airport, Santo Domingo, Dominican Republic. On November 12, 2001, the Airbus A300 flying the route crashed into the neighborhood of Belle Harbor on the Rockaway Peninsula of Queens, New York City, shortly after takeoff, killing all 251 passengers and nine crew members aboard, as well as five people on the ground. It is the second-deadliest aviation accident to have occurred in the United States, behind the crash of American Airlines Flight 191 in 1979, and the second-deadliest aviation incident involving an Airbus A300, after Iran Air Flight 655.
The location of the accident, and that it took place only two months after the September 11 attacks on the World Trade Center in nearby Manhattan, initially spawned fears of another terrorist attack, but the National Transportation Safety Board (NTSB) attributed the disaster to the first officer's overuse of rudder controls in response to wake turbulence from a preceding Japan Airlines Boeing 747-400 that took off minutes before it. According to the NTSB, the aggressive use of the rudder controls by the first officer, the result of a flawed training scenario that exaggerated the effects of wake turbulence, stressed the vertical stabilizer until it was ripped from the aircraft. The airliner's two engines also separated from the aircraft before impact due to the intense forces.
Aircraft and crew
The accident aircraft, registration N14053, was an Airbus A300 B4-605R delivered new to American Airlines on 12 July 1988. The aircraft's first flight was on 9 December 1987, and it was the first "R" model A300-600 built. On the day of the accident, it was in a two-class seating configuration with space for 251 passengers, and all 16 business-class seats and 235 economy-class seats were occupied. The aircraft was powered by two General Electric CF6-80C2A5 engines. On board were nine crew members, including 42-year-old Captain Edward States, who was the pilot monitoring and undertaking radio communications, and 34-year-old First Officer Sten Molin, who was the pilot flying.
Accident
The aircraft taxied to Runway 31L behind a Japan Airlines (JAL) Boeing 747-400 (JAL Flight 47) preparing for takeoff. The JAL flight was cleared for takeoff at 9:11:08 am EST. At 9:11:36, the tower controller cautioned Flight 587 about potential wake turbulence from a preceding 747.
At 9:13:28, the A300 was cleared for takeoff and left the runway at 9:14:29, about one minute and 40 seconds after the JAL flight had departed. The aircraft climbed to an altitude of 500 feet (150 m) and then entered a climbing left turn to a heading of 220°. At 9:15:00, the captain made initial contact with the departure controller, informing him that the airplane was at 1,300 ft (400 m) and climbing to 5,000 ft (1,500 m). The controller instructed the aircraft to climb to and maintain 13,000 ft (4,000 m). The flight data recorder (FDR) showed that the events leading to the crash began when the aircraft hit wake turbulence from the JAL flight in front of it at 9:15:36. In response to the turbulence, Molin moved the rudder from the right to the left and back again in quick succession from 9:15:52, causing sideslip until the lateral force caused composite lugs that attached the vertical stabilizer to fail at 9:15:58. The stabilizer separated from the aircraft and fell into Jamaica Bay, about 1 mi (1.6 km) north of the main wreckage site.
The aircraft pitched downward after the stabilizer loss. As the pilots struggled to control the aircraft, it entered a flat spin. The resulting aerodynamic loads sheared both engines from the aircraft, and they fell several blocks north and east of the main wreckage site, causing minor damage to a gas station and major damage to a home and a boat. The loss of engines cut power to the FDR at 9:16:01, while the cockpit voice recorder (CVR), using an emergency bus, stopped at 9:16:14.8 upon impact with the ground. At 9:16:04, the stall warning sounded on the CVR. The last recorded words were those of Molin saying, "What the hell are we into, we're stuck in it" (9:16:07) and States replying, "Get out of it, get out of it." The aircraft slammed into the ground at Newport Avenue and Beach 131st Street.
Investigation
Initial reactions and investigation
Because the crash occurred just two months after the September 11 attacks, which also took place in New York City, several major buildings, including the Empire State Building and the headquarters of the United Nations, were evacuated. The Port Authority of New York and New Jersey closed all bridges and tunnels between Manhattan and New Jersey and suspended PATH service for a few hours; traffic was disrupted, but the level was less than a typical Monday because it was Veterans Day. The New York metropolitan area's three major airports – JFK, LaGuardia, and Newark – remained closed for much of the day, leading to the cancellation of many flights. Air National Guard fighter jets patrolled U.S. airspace after the crash.
Rumors circulated that the plane had been destroyed in a terrorist plot. In May 2002, a Kuwaiti national named Mohammed Jabarah agreed to cooperate with investigators as part of a plea bargain. Among the details that Jabarah offered to authorities was a claim that Khalid Sheikh Mohammed's lieutenant had told him that Richard Reid and Abderraouf Jdey had been enlisted by al Qaeda to execute identical shoe-bombing plots as part of a second wave of attacks against the United States. According to the lieutenant, Jdey's bomb had successfully destroyed Flight 587, while Reid's attempt had been foiled. According to a Canadian government memorandum, Jdey, a naturalized Canadian citizen, was to use his Canadian passport to board the flight, but American Airlines' passenger manifest for Flight 587 did not list any passengers using Canadian passports. According to NTSB spokesman Ted Lopatkiewicz, the weight of the memo's veracity was questioned, as no evidence of a terrorist traveling on board was found. The evidence suggested that the aircraft was destroyed after a piece of the tail assembly, "the vertical fin, came off", while it did not indicate "any kind of event in the cabin."
NTSB investigation
On the afternoon of the crash, the NTSB launched an investigation in search for a probable cause. Over the next three months, they conducted 349 interviews and collected and reconstructed pieces of the aircraft. The Airbus A300 took off shortly after a JAL Boeing 747-400 using 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 force 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 NTSB concluded that the enormous stress on the vertical stabilizer 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 factors were characteristics of the Airbus A300-600's 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. It is connected to the fuselage with six attaching points. Each point has two sets of attachment lugs, one set 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, as 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.
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.
After the crash, Floyd Bennett Field's empty hangars were used as a makeshift morgue for the identification of crash victims.
Findings
According to the official accident report, the first officer repeatedly moved the rudder from fully left to fully right. This caused increasing sideslip angles. The resulting hazardous sideslip angle led to extremely high aerodynamic loads that separated the vertical stabilizer. If the first officer had stopped moving the rudder at any time before the vertical stabilizer failed, the aircraft would have leveled out on its own, and the accident would have been avoided. The aircraft performance study indicated that when the vertical stabilizer finally detached, the aerodynamic loads caused by the first officer's actions produced 203,000 pounds-force (900 kilonewtons) of force on the rudder, meaning that the vertical stabilizer did not fail until far in excess of the 100,000 lbf (440 kN) of force defined by the design envelope. The vertical stabilizer's structural performance was determined to be consistent with design specifications and to have exceeded certification requirements.
Contributing factors identified in the report included: First, the first officer's predisposition to overreact to wake turbulence; second, training provided by American Airlines that could have encouraged pilots to use the rudder aggressively; third, the first officer likely not understanding an airplane's response to full rudder at high airspeeds or the mechanism by which the rudder rolls a transport-category airplane; and finally, light rudder pedal forces and small pedal displacement of the A300-600 rudder pedal system that increased the airplane's susceptibility to rudder misuse.
Most aircraft require increased pressure on the rudder pedals to achieve the same amount of rudder control at a higher speed. The Airbus A300 and later Airbus A310 models do not operate on a fly-by-wire flight control system, but instead use conventional mechanical flight controls. The NTSB asserted that the A300-600 rudder control system was vulnerable to excessive rudder inputs. The Allied Pilots Association, in its submission to the NTSB, argued that the unusual sensitivity of the rudder mechanism amounted to a design flaw that Airbus should have communicated to the airline. The main rationale for their position came from a 1997 report that referenced 10 incidents in which A300 tail fins had been stressed beyond their design limitation.
Airbus charged that the crash was mostly American Airlines' fault, arguing that the airline did not train its pilots properly about the characteristics of the rudder. Aircraft tail fins are designed to withstand full rudder deflection in one direction when below maneuvering speed, but this does not guarantee that they can withstand an abrupt shift in rudder from one direction to the other, let alone multiple abrupt shifts, like those generated by the first officer on this flight. The NTSB indicated that American Airlines' Advanced Aircraft Maneuvering Program (AAMP) tended to exaggerate the effects of wake turbulence on large aircraft, creating a simulation scenario whereby turbulence from a 747 creates a 90° roll (rather than the likely 5 to 10° roll, though not explaining this to the pilots) to maximize the training challenge. Therefore, pilots were being inadvertently trained to react more aggressively than was necessary. According to author Amy Louise Fraher, this led to concerns of whether it was appropriate for the AAMP to be placing such importance on "the role of flight simulators in teaching airplane upset recovery at all." Fraher states that the key to understanding the crash of Flight 587 ultimately lay in "how the accident pilots' expectations about aircraft performance were erroneously established through 'clumsy' flight simulator training in American's AAMP."
Statement of probable cause
From the NTSB report of the accident:
The National Transportation Safety Board determines that the probable cause of this accident was the in-flight separation of the vertical stabilizer as a result of the loads beyond ultimate design that were created by the first officer's unnecessary and excessive rudder pedal inputs. Contributing to these rudder pedal inputs were characteristics of the Airbus A300-600 rudder system design and elements of the American Airlines Advanced Aircraft Maneuvering Program (AAMP).
Since the NTSB's report, American Airlines has modified its AAMP.