Of the four aircraft hijacked on September 11 – the others were American Airlines Flight 11, United Airlines Flight 175 and American Airlines Flight 77 – United Airlines Flight 93 was the only aircraft that did not reach its hijackers' intended target.
Af de fire fly kapret den 11. september (de andre værende American Airlines' flynummer 11, American Airlines' flynummer 77 og United Airlines' flynummer 175), var United Airlines' flynummer 93 det eneste, der ikke nåede dets tilsigtede mål.