At 9:33, the tower supervisor at Reagan National Airport picked up a hotline to the Secret Service and told the Service's operations center that "an aircraft [is] coming at you and not talking with us." This was the first specific report to the Secret Service of a direct threat to the White House. No move was made to evacuate the Vice President at this time. As the officer who took the call explained, "[I was] about to push the alert button when the tower advised that the aircraft was turning south and approaching Reagan National Airport."²⁰⁸

American 77 began turning south, away from the White House, at 9:34. It continued heading south for roughly a minute, before turning west and beginning to circle back. This news prompted the Secret Service to order the immediate evacuation of the Vice President just before 9:36. Agents propelled him out of his chair and told him he had to get to the bunker. The Vice President entered the underground tunnel leading to the shelter at 9:37.²⁰⁹

Once inside, Vice President Cheney and the agents paused in an area of the tunnel that had a secure phone, a bench, and television. The Vice President asked to speak to the President, but it took time for the call to be connected. He learned in the tunnel that the Pentagon had been hit, and he saw television coverage of smoke coming from the building.²¹⁰

The Secret Service logged Mrs. Cheney's arrival at the White House at 9:52, and she joined her husband in the tunnel. According to contemporaneous notes, at 9:55 the Vice President was still on the phone with the President advising that three planes were missing and one had hit the Pentagon. We believe this is the same call in which the Vice President urged the President not to return to Washington. After the call ended, Mrs. Cheney and the Vice President moved from the tunnel to the shelter conference room.²¹¹

United 93 and the Shootdown Order
On the morning of 9/11, the President and Vice President stayed in contact not by an open line of communication but through a series of calls. The President told us he was frustrated with the poor communications that morning. He could not reach key officials, including Secretary Rumsfeld, for a period of time. The line to the White House shelter conference room-and the Vice President-kept cutting off.²¹²

The Vice President remembered placing a call to the President just after entering the shelter conference room. There is conflicting evidence about when the Vice President arrived in the shelter conference room. We have concluded, from the available evidence, that the Vice President arrived in the room shortly before 10:00, perhaps at 9:58.The Vice President recalled being told, just after his arrival, that the Air Force was trying to establish a combat air patrol over Washington.²¹³