Watch Online Free FlixHQ. On September 11, 2001, one hijacked plane never reached its target when United 93 crashed in rural Pennsylvania. Previously classified streams of evidence are combined to piece together what really happened in a gripping minute-by-minute account. Evidence includes secret service documents; air traffic control transmissions; phone records; voicemails; first-person testimony; and a top-secret audio recording that helps reveal details of Flight 93's crucial final moments.