9/11 Commission

Bill Keaton, a retired air traffic controller who worked at Cleveland Center in Oberlin, Ohio, has shared his account of tracking United Airlines Flight 93 as it entered the facility's airspace on Sept. 11, 2001. Controllers heard unusual noises from the cockpit, watched the plane turn east, and lost transponder data around 9:40 a.m., leaving only a primary radar location. A hijacker transmission meant for passengers was overheard, and Keaton kept other aircraft clear of the plane's path as it headed toward Washington. The flight disappeared from radar after 10:03 a.m. and crashed near Shanksville, Pennsylvania, killing all 40 aboard.

Cleveland Center was evacuated soon after, though Keaton volunteered to remain with a small skeleton crew as the FAA ordered a nationwide ground stop, safely landing roughly 4,500 planes within three hours. Keaton has consistently rejected the "hero" label, calling the controllers' response commendable but not heroic.