In this Sept. 11, 2001 file photo, United Airlines Flight 175 collides into the south tower of the World Trade Center in New York as smoke billows from the north tower. (AP Photo/Chao Soi Cheong)
Featured Photo Galleries
In this Sept. 11, 2001 file photo, United Airlines Flight 175 collides into the south tower of the World Trade Center in New York as smoke billows from the north tower. (AP Photo/Chao Soi Cheong)
