William Durm

A number of witnesses see a helicopter flying near the Pentagon in the minutes before the attack there.
Jeffrey Mark Parsons, an assistant chief patrol agent with the United States Border Patrol, sees a blue and white helicopter that appears as if it is coming in to land, from a window on the 17th floor of the hotel he is staying at, near the Pentagon. Parsons will later recall that two or three minutes before the Pentagon attack occurs: “I saw [the helicopter] circle… between the hotel and the Pentagon, going toward the landing pad [at the Pentagon] where that airliner ultimately hit. And I thought that he landed on the pad.” Parsons will say the helicopter flies in at “a weird angle,” and recall that he has been staying at the Marriott Residence Inn in Arlington for almost a month, but has “never seen a helicopter approach the Pentagon from that direction before.” He will recognize the helicopter as a Huey because he has flown Hueys and knows they make “a very distinct sound.” According to John Darrell Sherwood, a Navy historian who interviews Parsons about the incident, the helicopter belongs to the US Park Police and has been instructed to intercept the aircraft that subsequently hits the Pentagon (see Shortly Before 9:35 a.m. September 11, 2001). [US Naval Historical Center, 12/13/2001; Goldberg et al., 2007, pp. 258]
A senior Air Force officer who is somewhere outside the Pentagon also sees a helicopter circling the Pentagon around this time, although he believes it to be a US military helicopter. Shortly after the Pentagon attack, the unnamed officer will tell a CNN reporter that the helicopter “disappeared behind the building where the helicopter landing zone is… and he then saw [a] fireball go into the sky” when the Pentagon is hit. [CNN, 9/11/2001]
Jennifer Reichert, who is stuck in traffic on Route 27 in front of the Pentagon, will describe that just before the attack, “A helicopter takes off from the heliport at the Pentagon.” She will add: “Minutes—maybe seconds—later, I hear it: American Airlines Flight 77 screams toward the Pentagon. The explosion [of the crash] shakes my car.” [Washington Post, 9/5/2002]
Secretary of Defense Donald Rumsfeld and Denny Watson, his CIA briefer, who are in Rumsfeld’s office at the Pentagon, see a helicopter flying very close to the building, outside the window of the office, and then pulling away just before the building is attacked (see Shortly Before 9:37 a.m. September 11, 2001). [Priess, 2016, pp. 244-245]
Perhaps due to the presence of this helicopter in the area, some people will initially think the attack on the Pentagon involves a helicopter hitting the building. Captain William Durm, the commander of the Pentagon’s Triservice Dental Clinic, will head to the building’s center courtyard shortly after the Pentagon is hit. Someone there will tell him a helicopter has hit the other side of the building. [Marble and Milhiser, 9/2004, pp. 11] Some early news reports will suggest a helicopter crashed into the Pentagon. [Thomas Crosbie Media, 9/11/2001; Poynter Institute, 9/2/2002] One report will claim that “one aircraft and a helicopter have crashed into the Pentagon.” [Airline Industry Information, 9/11/2001] Vice President Dick Cheney will tell NBC’s Meet the Press that “the first reports on the Pentagon attack suggested a helicopter” hit the building. [Meet the Press, 9/16/2001] The Guardian will report that one witness claims the explosion that occurs when the Pentagon is hit blows up a helicopter circling overhead. [Guardian, 9/12/2001] New York Times columnist William Safire will report that, at approximately this time, Cheney is told that either another plane or “a helicopter loaded with explosives” is heading for the White House. [New York Times, 9/13/2001]