had both been enlisted by the al-Qaeda chief to carry out identical shoe-bombing plots as part of a second wave of attacks against the United States. According to this lieutenant, Jdey's bomb had successfully blown up Flight 587, while Reid's attempt had been foiled. In May 2002, a Canadian government memorandum repeated the claims suggesting that Jdey had a role in the crash, while conceding that the reliability of the source of that information – Khalid Sheikh Mohammed's lieutenant – was unknown. According to the memo, Jdey – a naturalized Canadian citizen – was to use his Canadian passport to board the flight. While American Airlines' passenger manifest did indicate citizens boarding with passports from the United States, the Dominican Republic, Taiwan, France, Haiti, and Israel, no passengers boarded using a Canadian passport. 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 brought down 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. The vertical stabilizer is connected to the fuselage with six attaching points. Each point has two sets of attachment lugs, one made