Flight 11 disappears from primary radar four seconds before it hits the North Tower of the World Trade Center (see 8:46 a.m. September 11, 2001), according to an FAA timeline. [Federal Aviation Administration, 9/17/2001 ] At the FAA’s Boston Center, Colin Scoggins, the center’s military liaison, notices the loss of the plane’s primary radar track. As the center only monitors high-level air traffic, its radar information does not pick up aircraft below 1,500 feet. But Scoggins does not realize Flight 11 has crashed. The Boston Center’s last known position for the plane before it disappears is nine miles northeast of New York’s JFK International Airport. [Spencer, 2008, pp. 49]