U.S. flag flies over the crash site of United Airlines flight 93 in Shanksville, Pennsylvania.
FBI investigators search the United 93 crash site where 44 people, crew and passengers, died on Sept. 11, 2001.
The temporary memorial to the 44 victims of United 93 fashioned within the days after the Sept. 11th attacks.
A young mourner wipes tears away as she remembers those who died on United 93, during a September 11th memorial service in Shanksville, Pennsylvania.
The "Flight 93 Hero Flag" is held on the Pennsylvania field where United Flight 93 crashed.
A cross is set at the temporary memorial for the crew and passengers of United Flight 93.
A U.S. military helicopter flies over the makeshift memorial at the crash site.
Mourners set up the "Angels of Freedom" memorial near Shanksville, Pennsylvania.
American military jets fly in the "Missing Man" over the memorial ceremony for Sept. 11th attacks.
The "Flight 93 Hero Flag" flies at the United Flight 93 crash site.