It has been widely reported that on September 11, 2001, four passenger aircraft were hijacked, and three of them subsequently hit their intended targets in New York and Washington. Less well known is that, during the two hours over which the 9/11 attacks occurred, air traffic controllers and military personnel had to devote significant time to a fifth plane that was incorrectly reported as hijacked. This aircraft was, in the words of one military official, "the first red herring of the day." [1]

The aircraft was Delta Air Lines Flight 1989, a Boeing 767 that had taken off from Boston. From around 9:30 a.m., it was repeatedly suspected of having been hijacked. Even though subsequent events had indicated the aircraft was fine, a police SWAT team and FBI agents were sent out to it after it made an emergency landing in Cleveland, Ohio, and it was not until about two hours after the plane landed that all its passengers had been allowed off.