Mohammed Atta and Marwan al-Shehhi obtained commercial pilot instruction in 2000 at Huffman Aviation, a flight school and aviation firm based in Venice, Florida. The owner, Rudi Dekkers, was forced to sell his business and has since written a book about his experience titled, "Guilty by Association".
Photo: Small airplanes from the Florida Flight Training Center sit on the tarmac at the Venice Municipal Airport July 12, 2002 in Venice, Florida. Terrorist Ziad Samir Jarrah, who was on United Airlines Flight 93, and two other terrorists involved in the September 11, 2001 attacks are reported to have taken flying lessons at the center. (Photo by Joe Raedle/Getty Images)