September 11, 2001 Research & Archives

Flight controllers ask the United Airlines Flight 175 pilots to look for a lost American Airlines plane 10 miles to the south—a reference to Flight 11. They respond that they can see it. They are told to keep away from it. [Guardian, 10/17/2001; Boston Globe, 11/23/2001; 9/11 Commission, 6/17/2004]

Apparently, Flight 175 is not told Flight 11 has been hijacked. Flight 175 itself is hijacked a few minutes later (see 8:41 a.m.-8:42 a.m. September 11, 2001).