Aviation obsessives with cameras and Internet connections have become a threat to cover stories established by the CIA to mask its undercover operations and personnel overseas. U.S. intel sources complain that plane spotters" -- hobbyists who photograph airplanes landing or departing local airports and post the pix on the Internet -- made it possible for CIA critics recently to assemble details of a clandestine transport system the agency set up to secretly move cargo and people -- including terrorist suspects -- around the world.

"