According to Pilots for Truth, the cockpit door of AA-77 was never opened, what means that no hypothetical hijacker could ever have entered in that room:
Newly decoded data provided by an independent researcher and computer programmer from Australia exposes alarming evidence that the reported hijacking aboard American Airlines Flight 77 was impossible to have existed. A data parameter labeled "FLT DECK DOOR", cross checks with previously decoded data obtained by Pilots For 9/11 Truth from the National Transportation Safety Board (NTSB) through the Freedom Of Information Act.
On the morning of September 11, 2001, American Airlines Flight 77 departed Dulles International Airport bound for Los Angeles at 8:20 am Eastern Time. According to reports and data, a hijacking took place between 08:50:54 and 08:54:11 in which the hijackers allegedly crashed the aircraft into the Pentagon at 09:37:45. Reported by CNN, according to Ted Olson, wife Barbara Olson had called him from the reported flight stating, "...all passengers and flight personnel, including the pilots, were herded to the back of the plane by armed hijackers...". However, according to Flight Data provided by the NTSB, the Flight Deck Door was never opened in flight. How were the hijackers able to gain access to the cockpit, remove the pilots, and navigate the aircraft to the Pentagon if the Flight Deck Door remained closed?
According to Voltaire Network, the pilot was a top level special operations professional:
Former U.S. Navy F-4 Phantom jet pilot, Charles F. Burlingame also served as Pentagon spokesman during Operation Desert Storm. He was in charge of an attack simulation exercise, helping to craft response plans in the event of a commercial airliner hitting the Pentagon. (...) His sister Debra Burlingame co-chairs with Liz Cheney (former Vice-President Cheney’s daughter) the Keep America Safe association (one of those fascist scaremonger NGOs).Extremely suspicious, right? There has been a lot of people who have reported that not only was impossible for a commercial plane to make such a low flight attack maneuver but that nobody ever saw such plane, directly or in any record, and that the impact onto the Pentagon lacks a clear signature of a large plane: no signs of where the wings hit.
For further detail of the many incognites and secrets surrounding 9/11 attacks, check the many articles collected through the years at Voltaire Network on this issue.