Exactly six months after terrorists Mohamed Atta and Marwan Alshehhi flew two jetliners into the World Trade Center, the Florida flight school that trained the men received paperwork showing that their student visas had been approved. The two suicide hijackers had applied for the visas through their flight school, Huffman Aviation International, in August 2000. But because of backlogs and an antiquated processing system at the Immigration and Naturalization Service, notification of the approval did not arrive at the Venice, Fla., flight school until Monday. Full Story