1.  No physical, documentary, or analytical evidence provides a convincing explanation of why Atta and Omari drove to Portland, Maine, from Boston on the morning of September 10, only to return to Logan on Flight 5930 on the morning of September 11. However, Atta reacted negatively when informed in Portland that he would have to check in again in Boston. Michael Touhey interview (May 27, 2004).Whatever their reason, the Portland Jetport was the nearest airport to Boston with a 9/11 flight that would have arrived at Logan in time for the passengers to transfer to American Airlines Flight 11, which had a scheduled departure time of 7:45 A.M. See Tom Kinton interview (Nov. 6, 2003); Portland International Jetport site visit (Aug. 18, 2003).

Like the other two airports used by the 9/11 hijackers (Newark Liberty International Airport and Washington Dulles International Airport), Boston's Logan International Airport was a "Category X" airport: i.e., among the largest facilities liable to highest threat, and generally subject to greater security requirements. See FAA report, "Civil Aviation Security Reference Handbook," May 1999, pp. 117-118.Though Logan was selected for two of the hijackings (as were both American and United Airlines), we found no evidence that the terrorists targeted particular airports or airlines. Nothing stands out about any of them with respect to the only security layer that was relevant to the actual hijackings: checkpoint screening. See FAA briefing materials, "Assessment and Testing Data for BOS, EWR, and IAD," Oct. 24, 2001. Despite security problems at Logan (see, e.g., two local Fox 25 television investigative reports in February and April 2001, and an email in August 2001 from a former FAA special agent to the agency's leadership regarding his concerns about lax security at the airport), no evidence suggests that such issues entered into the terrorists' targeting: they simply booked heavily fueled east-to-west transcontinental flights of the large Boeing aircraft they trained to fly that were scheduled to take off at nearly the same time. See Matt Carroll, "Fighting Terror Sense of Alarm; Airlines Foiled Police Logan Probe," Boston Globe, Oct. 17, 2001, p. B1.

2.  CAPPS was an FAA-approved automated system run by the airlines that scored each passenger's profile to identify those who might pose a threat to civil aviation. The system also chose passengers at random to receive additional security scrutiny. Ten out of the 19 hijackers (including 9 out of 10 on the two American Airlines flights) were identified via the CAPPS system. According to the procedures in place on 9/11, in addition to those flagged by the CAPPS algorithm, American's ticket agents were to mark as "selectees" those passengers who did not provide correct responses to the required security questions, failed to show proper identification, or met other criteria. See FAA report, "Air Carrier Standard Security Program," May 2001, pp. 75-76; FAA record of interview, Donna Thompson, Sept. 23, 2001; Chuck Severance interview (Apr. 15, 2004); Jim Dillon interview (Apr. 15, 2004); Diane Graney interview (Apr. 16, 2004). It appears that Atta was selected at random. See Al Hickson briefing (June 8, 2004).

3. The call was placed from a pay phone in Terminal C (between the screening checkpoint and United 175's boarding gate). We presume Shehhi made the call, but we cannot be sure. Logan International Airport site visit (Aug. 15, 2003); see also FBI response to Commission briefing request no. 6, undated (topic 11).

4.  Flight 11 pushed back from Gate 32 in Terminal B at 7:40. See AAL response to the Commission's February 3, 2004, requests, Mar. 15, 2004.

5.  See UAL letter, "Flight 175-11Sep01 Passenger ACI Check-in History," July 11, 2002. Customer service representative Gail Jawahir recalled that her encounter with the Ghamdis occurred at "shortly before 7 A.M.," and when shown photos of the hijackers, she indicated that Mohand al Shehri resembled one of the two she checked in (suggesting they were Banihammad and Shehri). However, she also recalled that the men had the same last name and had assigned seats on row 9 (i.e., the Ghamdis), and that account has been adopted here. In either case, she almost certainly was dealing with one set of the Flight 175 hijackers. See FBI reports of investigation, interviews of Gail Jawahir, Sept. 21, 2001; Sept. 28, 2001. Even had the hijackers been unable to understand and answer the two standard security questions, the only consequence would have been the screening of their carry-on and checked bags for explosives. See FAA report, "Air Carrier Standard Security Program," May 2001, p. 76.

6.  For Flight 11, two checkpoints provided access to the gate. The second was opened at 7:15 A.M. The FAA conducted many screener evaluations between September 11, 1999, and September 11, 2001.At the primary checkpoints, in aggregate, screeners met or exceeded the average for overall, physical search, and X-ray detection, while falling below the norm for metal detection. No FAA Special Assessments (by "red teams") were done at Logan security checkpoints during the two years prior to September 11, 2001. See FAA briefing materials, "Assessment and Testing Data for BOS, EWR, and IAD," Oct. 24, 2001.

7.  See Air Transport Association/Regional Airlines Association (ATA/RAA) report, "Air Carriers Checkpoint Operations Guide," Aug. 1999; FAA report, "Air Carrier Standard Security Program, "May 2001, appendix VI.

8.  Mary Carol Turano interview (Mar. 11, 2004); FBI reports of investigation, interview of Nilda Cora, Oct. 4, 2001; interview of William Thomas, Sept. 14, 2001; interview of Jennifer Gore, Sept. 12, 2001; interview of Claudia Richey, Sept. 15, 2001; interview of Rosarito Rivera, Sept. 25, 2001.

9.  See TSA report, "Selectee Status of September 11th Hijackers," undated. For boarding and seating information, see AAL record, SABRE information on Flight 11, Sept. 11, 2001.These boarding times from the American system are approximate only; for Flight 11, they indicated that some passengers "boarded" after the aircraft had pushed back from the gate. See AAL response to the Commission's February 3, 2004, requests, Mar. 15, 2004.

10.  See TSA report, "Selectee Status of September 11th Hijackers, "undated; see also UAL letter, "Flight 175- 11 Sep01 Passenger ACI Check-in History," July 11, 2002.

11. The Hazmis checked in at 7:29; the airline has not yet been able to confirm the time of Hanjour's check-in. However, it had to have taken place by 7:35, when he appears on the checkpoint videotape. See AAL record, SABRE information for Flight 77, Sept. 11, 2001; AAL response to the Commission's February 3, 2004, requests, Mar. 15, 2004; Metropolitan Washington Airports Authority videotape, Dulles main terminal checkpoints, Sept. 11, 2001.

12.  See TSA report, "Selectee Status of September 11th Hijackers, "undated; see also FAA report, "Selectee List AALA #77," undated; FBI report of investigation, interview of Vaughn Allex, Sept. 12, 2001;Vaughn Allex interview (July 13, 2004).

13. The FAA conducted many screener evaluations at Dulles between September 11, 1999, and September 11, 2001.While the test results for physical search exceeded the national average, both the metal detector and X-ray results were below average. See FAA briefing materials, "Assessment and Testing Data for BOS, EWR, and IAD," Oct. 24, 2001.

14.  Metropolitan Washington Airports Authority videotape, Dulles main terminal checkpoints, Sept. 11, 2001; see also Tim Jackson interview (Apr. 12, 2004).

15.  Metropolitan Washington Airports Authority videotape, Dulles main terminal checkpoints, Sept. 11, 2001; see also Tim Jackson interview (Apr. 12, 2004).

16.  For investigation findings, see FAA report, "American Airlines Flight #77: Hijacking and Crash into the Pentagon, Sept. 11, 2001," undated. For screener evaluations, see Tim Jackson interview (Apr. 12, 2004).

17.  See AAL record, SABRE information for Flight 77, Sept. 11, 2001;AAL response to the Commission's February 3, 2004, requests, Mar. 15, 2004.

18.  UAL record, Flight 93 EWR bag loading status, Sept. 11, 2001; UAL record, Flight 93 EWR ACI passenger history, Sept. 11, 2001; UAL record, Flight 93 EWR full bag history, Sept. 11, 2001;TSA report, "Selectee Status of September 11th Hijackers," undated; FBI report, "The Final 24 Hours," Dec. 8, 2003.

19. The FAA conducted many screener evaluations at Newark between September 11, 1999, and September 11, 2001. Detection rates for metal detection, physical searches, and X-rays all met or exceeded the national averages. See FAA briefing materials, "Assessment and Testing Data for BOS, EWR, and IAD," Oct. 24, 2001; see also FAA report, "United Airlines Flight 93, September 11, 2001, Executive Report," Jan. 30, 2002.

20.  UAL record, Flight 93 EWR ACI passenger history, Sept. 11, 2001; see also FBI report, "The Final 24 Hours," Dec. 8, 2003.

21. While Flights 11 and 77 were at or slightly above the average number of passengers for the respective flights that summer, Flights 175 and 93 were well below their averages. We found no evidence to indicate that the hijackers manipulated the passenger loads on the aircraft they hijacked. Financial records did not reveal the purchase of any tickets beyond those the hijackers used for themselves. See FBI response to Commission briefing request no. 6, undated (topic 8);AAL report, "Average Load Factor by Day-of-Week," undated (for Flights 11 and 77 from June 11, 2001, to Sept. 9, 2001);AAL response to the Commission's supplemental document requests, Jan. 20, 2004; UAL report, Flight 175 BOS-LAX Load Factors, undated (from June 1, 2001, to Sept. 11, 2001); UAL report, "Explanation of Load Factors," undated.

22.  See AAL response to the Commission's February 3, 2004, requests, Mar. 15, 2004; AAL record, Dispatch Environmental Control/Weekly Flight Summary for Flight 11, Sept. 11, 2001;AAL report, "Flight Attendant Jump Seat Locations During Takeoff And Flight Attendant Typical Cabin Positions During Start of Cabin Service," undated; AAL report, "Passenger Name List, Flight 11/September 11," undated.

23.  Commission analysis of NTSB and FAA air traffic control and radar data. See AAL record, Dispatch Environmental Control/Weekly Flight Summary for Flight 11, Sept. 11, 2001; NTSB report, "Flight Path Study-American Airlines Flight 11," Feb. 19, 2002; Bill Halleck and Peggy Houck interview (Jan. 8, 2004).The initial service assignments for flight attendants on American 11 would have placed Karen Martin and Bobbi Arestegui in first class; Sara Low and Jean Roger in business class; Dianne Snyder in the midcabin galley; Betty Ong and Amy Sweeney in coach; and Karen Nicosia in the aft galley. Jeffrey Collman would have been assigned to work in coach, but to assist in first class if needed. See AAL report, "Flight Attendant Jump Seat Locations During Takeoff And Flight Attendant Typical Cabin Positions During Start of Cabin Service," undated; Bob Jordan briefing (Nov. 20, 2003).

24.  NTSB report, Air Traffic Control Recording-American Airlines Flight 11, Dec. 21, 2001; NTSB report, Air Traffic Control Recording-United Airlines Flight 175, Dec. 21, 2001. Given that the cockpit crew of American 11 had been acknowledging all previous instructions from air traffic control that morning within a matter of seconds, and that when the first reporting of the hijacking was received a short time later (the 8:19 call from Betty Ong) a number of actions had already been taken by the hijackers, it is most likely that the hijacking occurred at 8:14 A.M.

25. An early draft of an executive summary prepared by FAA security staff for the agency's leadership referred to an alleged report of a shooting aboard Flight 11.We believe this report was erroneous for a number of reasons- there is no evidence that the hijackers purchased firearms, use of a gun would be inconsistent with the otherwise common tactics employed by the hijackers, the alleged shooting victim was seated where witness accounts place the stabbing victim (9B), and, most important, neither Betty Ong nor Amy Sweeney, the only two people who communicated to the ground from aboard the aircraft, reported the presence of a gun or a shooting. Both reported knives and stabbings. AAL transcript, telephone call from Betty Ong to Nydia Gonzalez, Sept. 11, 2001;AAL transcript, telephone call from Nydia Gonzalez to Craig Marquis, Sept. 11, 2001; AAL transcript, telephone call from Nancy Wyatt to Ray Howland, Sept. 11, 2001; Michael Woodward interview (Jan. 25, 2004).The General Accounting Office looked into the gun story and was unable to corroborate it. GAO report, summary of briefing re investigation, Aug. 30, 2002.

26.  Craig Marquis interview (Nov. 19, 2003); Michael Woodward interview (Jan. 25, 2004); Jim Dillon interview (Apr. 15, 2004). See also AAL transcript, telephone call from Betty Ong to Nydia Gonzalez, Sept. 11, 2001. At the time of the hijacking, American Airlines flight attendants all carried cockpit keys on their person. See Craig Marquis, Craig Parfitt, Joe Bertapelle, and Mike Mulcahy interview (Nov. 19, 2003).

27.  AAL transcript, telephone call from Nydia Gonzalez to Craig Marquis, Sept. 11, 2001; Obituary, "Daniel Lewin," Washington Post, Sept. 22, 2001, p. B7.

28.  AAL transcript, telephone call from Betty Ong to Nydia Gonzalez, Sept. 11, 2001; AAL transcript, telephone call from Nydia Gonzalez to Craig Marquis, Sept. 11, 2001. Regarding the claim of a bomb, see Michael Woodward interview (Jan. 25, 2004).

29.  Calls to American's reservations office are routed to the first open line at one of several facilities, among them the center in Cary, N.C. See Nydia Gonzalez interview (Nov. 19, 2003). On standard emergency training, see FAA report, "Air Carrier Standard Security Program," May 2001, pp. 139j-139o; Don Dillman briefing (Nov. 18, 2003); Bob Jordan briefing (Nov. 20, 2003).The call from Ong was received initially by Vanessa Minter and then taken over by Winston Sadler; realizing the urgency of the situation, he pushed an emergency button that simultaneously initiated a tape recording of the call and sent an alarm notifying Nydia Gonzalez, a supervisor, to pick up on the line. Gonzalez was paged to respond to the alarm and joined the call a short time later. Only the first four minutes of the phone call between Ong and the reservations center (Minter, Sadler, and Gonzalez) was recorded because of the time limit on the recently installed system. See Nydia Gonzalez interview (Nov. 19, 2003); Nydia Gonzalez testimony, Jan. 27, 2004.

30.  AAL transcript, telephone call from Betty Ong to Nydia Gonzalez, Sept. 11, 2001.

31.  See Nydia Gonzalez interview (Nov. 19, 2003); Craig Marquis interviews (Nov. 19, 2003; Apr. 26, 2004); AAL record, Dispatch Environmental Control/Weekly Flight Summary for Flight 11, Sept. 11, 2001; AAL transcript, telephone call from Bill Halleck to BOS ATC, Sept. 11, 2001.The Air Carrier Standard Security Program required airlines to immediately notify the FAA and FBI upon receiving information that an act or suspected act of airplane piracy was being committed.

32.  See FAA recording, Boston Air Route Traffic Control Center, position 46R, at 8:25 A.M.; Air Traffic Control Recording-American Airlines Flight 11, Dec. 21, 2001. Starting at 8:22,Amy Sweeney attempted by airphone to contact the American Airlines flight services office at Logan, which managed the scheduling and operation of flight attendants. Sweeney's first attempt failed, as did a second at 8:24.When she got through to Nunez, the latter thought she had reported her flight number as 12. Michael Woodward, supervisor at the Boston office, hearing that a problem had been reported aboard an American airplane, went to American's gate area at Logan with his colleague Beth Williams. Woodward noted that the morning bank of flights had all departed Boston and the gate area was quiet. He further realized that Flight 12 had not even departed yet, so he and Williams returned to the office to try to clarify the situation. See FBI report, "American Airlines Airphone Usage," Sept. 20, 2001; Michael Woodward interview (Jan. 25, 2004).The phone call between Sweeney and Woodward lasted about 12 minutes (8:32-8:44) and was not taped. See AAL email, Woodward to Schmidt, "Flight 11 Account of events," Sept. 19, 2001;AAL notes, Michael Woodward handwritten notes, Sept. 11, 2001; FBI report of investigation, interview of Michael Woodward, Sept. 13, 2001; AAL report, interview of Michael Woodward, Sept. 11, 2001; AAL transcript, telephone call from Nancy Wyatt to Ray Howland, Sept. 11, 2001.

33.  See AAL transcript, telephone call from Nydia Gonzalez to Craig Marquis, Sept. 11, 2001; NTSB report, "Flight Path Study-American Airlines Flight 11," Feb. 19, 2002.AAL transcript, telephone call from Nydia Gonzalez to Craig Marquis, Sept. 11, 2001; AAL transcript, telephone call from Nancy Wyatt to Ray Howland, Sept. 11, 2001.

34.  Michael Woodward interview (Jan. 25, 2004).

35. AAL transcript, telephone call from Nydia Gonzalez to Craig Marquis, Sept. 11, 2001; Michael Woodward interview (Jan. 25, 2004);AAL, Michael Woodward notes, Sept. 11, 2001.Also at this time American Airlines completed its "lockout" procedure for Flight 11, which restricted access to information about a hijacked flight in accordance with the Air Carrier Standard Security program. See FAA report,"Air Carrier Standard Security Program," May 2001, p. 110.

36. AAL transcript, telephone call from Nancy Wyatt to Ray Howland, Sept. 11, 2001; Michael Woodward interview (Jan. 25, 2004).

37.  AAL transcript, telephone call from Nydia Gonzalez to Craig Marquis, Sept. 11, 2001.

38.  Ibid.; Michael Woodward interview (Jan. 25, 2004).

39.  NTSB report, "Flight Path Study-American Airlines Flight 11," Feb. 19, 2002.

40. The 56 passengers represented a load factor of 33.33 percent of the airplane's seating capacity of 168, below the 49.22 percent for Flight 175 on Tuesdays in the three-month period prior to September 11, 2001. See UAL report, Flight 175 BOS-LAX Load Factors, undated (from June 1, 2001, to Sept. 11, 2001). Nine passengers holding reservations for Flight 175 did not show for the flight. They were interviewed and cleared by the FBI. FAA report, "Executive Summary," Sept. 12, 2001; FAA report, "Executive Summary, Chronology of a Multiple Hijacking Crisis, September 11, 2001," Sept. 17, 2001; UAL record, Flight 175 ACARS report, Sept. 11, 2001; UAL record, Flight 175 Flight Data Recap, Sept. 11, 2001.

41.  FAA report, "Executive Summary," Sept. 12, 2001; FAA report, "Executive Summary, Chronology of a Multiple Hijacking Crisis, September 11, 2001," Sept. 17, 2001; NTSB report, "Flight Path Study-United Airlines 175," Feb. 19, 2002; NTSB report, Air Traffic Control Recording-United Airlines Flight 175, Dec. 21, 2001. At or around this time, flight attendants Kathryn Laborie and Alfred Marchand would have begun cabin service in first class; with Amy King and Robert Fangman in business class; and with Michael Tarrou, Amy Jarret, and Alicia Titus in economy class. See UAL report, "Flight 175 Flight Attendant Positions/Jumpseats," undated. United flight attendants, unlike those at American, did not carry cockpit keys. Instead, such keys were stowed in the cabin-on Flight 175, in the overhead bin above seats 1A and 1B in first class. See Don Dillman briefing (Nov. 18, 2003); Bob Jordan briefing (Nov. 20, 2003).

42. Asked by air traffic controllers at 8:37 to look for an American Airlines 767 (Flight 11), United 175 reported spotting the aircraft at 8:38. At 8:41, the flight crew reported having "heard a suspicious transmission" from another aircraft shortly after takeoff, "like someone keyed the mike and said everyone stay in your seats." See NTSB report, Air Traffic Control Recording-United Airlines Flight 175, Dec. 21, 2001.

43.  See Marc Policastro interview (Nov. 21, 2003); FBI reports of investigation, interview of Lee Hanson, Sept. 11, 2001; interview of Marc Policastro, Sept. 11, 2001; interview of Louise Sweeney, Sept. 28, 2001; interview of Ronald May, Sept. 11, 2001. On both American 11 and United 175, Boeing 767 double-aisled aircraft, the hijackers arrayed themselves similarly: two seated in first class close to the cockpit door, the pilot hijacker seated close behind them, and at least one other hijacker seated close behind the pilot hijacker. Hijackers were seated next to both the left and right aisles. On American 77 and United 93, Boeing 757 single-aisle aircraft, the pilot hijacker sat in the first row, closest to the cockpit door. See FBI report, "Summary of Penttbom Investigation," Feb. 29, 2004, pp. 67-69; AAL schematics for Flight 11 and Flight 77; UAL schematics for Flight 175 and Flight 93.

44.  NTSB report, "Flight Path Study-United Airlines 175," Feb. 19, 2002; NTSB report, Air Traffic Control Recording-United Airlines Flight 175, Dec. 21, 2001.

45.  See FBI report of investigation, interview of Lee Hanson, Sept. 11, 2001.

46.  Flight crew on board UAL aircraft could contact the United office in San Francisco (SAMC) simply by dialing *349 on an airphone. See FBI report of investigation, interview of David Price, Jan. 24, 2002.At some point before 9:00, SAMC notified United's headquarters of the emergency call from the flight attendant. See Marc Policastro interview (Nov. 21, 2003); FBI report of investigation, interview of Marc Policastro, Sept.11, 2001; Rich Miles interiew (Nov. 21, 2003).

47.  NTSB report, "Flight Path Study-United Airlines 175," Feb. 19, 2002.

48.  See FBI reports of investigation, interview of Julie Sweeney, Oct. 2, 2001; interview of Louise Sweeney, Sept. 28, 2001.

49.  See FBI report of investigation, interview of Lee Hanson, Sept. 11, 2001.

50.  See ibid.; interview of Louise Sweeney, Sept. 28, 2001.

51.  NTSB report, "Flight Path Study-United Airlines 175," Feb. 19, 2002.

52.  AAL report, "Flight Attendant Jump Seat Locations During Takeoff And Flight Attendant Typical Cabin Positions During Start of Cabin Service," undated;AAL email,Young to Clark, "Flight Crews," Sept. 12, 2001;AAL record, Dispatch Environmental Control/Weekly Flight Summary for Flight 11, Sept. 11, 2001.

53. AAL record, System Operations Command Center (SOCC) log, Sept. 11, 2001, p. 2; NTSB report, "Flight Path Study-American Airlines Flight 77," Feb. 19, 2002. Flight attendant Renee May would likely have started working in the first-class galley; Michele Heidenberger would have been in the aft galley; Jennifer Lewis would have been in first class; and Kenneth Lewis would have been in the main cabin. On cabin service, see AAL report, "Flight Attendant Jump Seat Locations During Takeoff And Flight Attendant Typical Cabin Positions During Start of Cabin Service," undated. For cruising altitude, see NTSB report, "Flight Path Study-American Airlines Flight 77," Feb. 19, 2002. On events in the cabin, see FAA recording, Indianapolis Air Traffic Control Center, position HNN R, Sept. 11, 2001; FBI report of investigation, interview of Theodore Olson, Sept. 11, 2001; FBI report of investigation, interview of Ronald and Nancy May, Sept. 12, 2001; AAL record, Dispatch Environmental Control/Weekly Flight Summary for Flight 11, Sept. 11, 2001.

54. Air traffic control notified American's headquarters of the problem, and the airline began attempts to contact the flight by 8:59 via ACARS. See NTSB report, "Flight Path Study-American Airlines Flight 77," Feb. 19, 2002. On American 11, the transponder signal was turned off at 8:21; on United 175, the code was changed at 8:47; on American 77, the signal was turned off at 8:56; and on United 93, the signal was turned off at 9:41. See FAA report, "Summary of Air Traffic Hijack Events: September 11, 2001," Sept. 17, 2001; Richard Byard interview (Sept.

24, 2003); Linda Povinelli interview (Sept. 24, 2003); see also NTSB report, Air Traffic Control Recording-American Airlines Flight 77, Dec. 21, 2001; AAL record, Dispatch Environmental Control/Weekly Flight Summary for Flight 11, Sept. 11, 2001.

55.  Gerard Arpey interview (Jan. 8, 2004); Larry Wansley interview (Jan. 8, 2004);AAL record, System Operations Command Center (SOCC) log, Sept. 11, 2001.

56.  FBI report, "American Airlines Airphone Usage," Sept. 20, 2001; FBI report of investigation, interview of Ronald and Nancy May, Sept. 12, 2001.

57. The records available for the phone calls from American 77 do not allow for a determination of which of four "connected calls to unknown numbers" represent the two between Barbara and Ted Olson, although the FBI and DOJ believe that all four represent communications between Barbara Olson and her husband's office (all family members of the Flight 77 passengers and crew were canvassed to see if they had received any phone calls from the hijacked flight, and only Renee May's parents and Ted Olson indicated that they had received such calls).The four calls were at 9:15:34 for 1 minute, 42 seconds; 9:20:15 for 4 minutes, 34 seconds; 9:25:48 for 2 minutes, 34 seconds; and 9:30:56 for 4 minutes, 20 seconds. FBI report, "American Airlines Airphone Usage," Sept. 20, 2001; FBI report of investigation, interview of Theodore Olson, Sept. 11, 2001; FBI report of investigation, interview of Helen Voss, Sept. 14, 2001;AAL response to the Commission's supplemental document request, Jan. 20, 2004.

58.  FBI report, "American Airlines Airphone Usage," Sept. 20, 2001; FBI report of investigation, interview of Theodore Olson, Sept. 11, 2001.

59.  See FAA report, "Report of Aircraft Accident," Nov. 13, 2001; John Hendershot interview (Dec. 22, 2003); FAA report, "Summary of Air Traffic Hijack Events: September 11, 2001," Sept. 17, 2001; NTSB report, "Flight Path Study-American Airlines Flight 77," Feb. 19, 2002; Commission analysis of radar data.

60.  See FAA report, "Summary of Air Traffic Hijack Events: September 11, 2001," Sept. 17, 2001; NTSB report, "Flight Path Study-American Airlines Flight 77," Feb. 19, 2002; FAA report, "Report of Aircraft Accident," Nov. 13, 2001.

61.  See NTSB report, "Flight Path Study-American Airlines Flight 77," Feb. 19, 2002;TSA report, "Criminal Acts Against Civil Aviation for 2001," Aug. 20, 2002, p. 41.

62.  The flight attendant assignments and seating included Chief Flight Attendant Deborah Welsh (first class, seat J1 at takeoff); Sandra Bradshaw (coach, seat J5);Wanda Green (first class, seat J4); Lorraine Bay (coach, seat J3); and CeeCee Lyles (coach, seat J6). See UAL response to Commission questions for the record, Apr. 5, 2004; FAA report, "Chronology of the September 11 Attacks and Subsequent Events Through October 24, 2001," undated; UAL records, copies of electronic boarding passes for Flight 93, Sept. 11, 2001; Bob Varcadipane interview (May 4, 2004); Newark Tower briefing (May 4, 2004).

63.  Although the flight schedule indicates an 8:00 A.M. "departure," this was the time the plane left the gate area. Taxiing from the gate to the runway normally took about 15 minutes. Bob Varcadipane interview (May 4, 2004); Newark Tower briefing (May 4, 2004).

64.  Commission analysis of FAA air traffic control data. On the FAA's awareness of multiple hijackings, see AAL transcript, telephone call from Nydia Gonzalez to Craig Marquis, Sept. 11, 2001; Craig Marquis interview (Nov. 19, 2003);AAL record, System Operations Command Center (SOCC) log, Sept. 11, 2001; UAL System Operations Control briefing (Nov. 20, 2003); Rich Miles interview (Nov. 21, 2003); UAL report, "Timeline: Dispatch/SMFDO Activities-Terrorist Crisis," undated.

65.  FAA audio file, Boston Center, position 46R, 8:24:38 and 8:24:56; Peter Zalewski interview (Sept. 23, 2003).

66.  On September 6, 1970, members of the Popular Front for the Liberation of Palestine hijacked a Pan American Boeing 747, a TWA Boeing 707, and a Swissair DC-8. On September 9, a British airliner was hijacked as well. An attempt to hijack an Israeli airliner was thwarted. The Pan American plane landed in Cairo and was blown up after its passengers were released. The other three aircraft were flown to Dawson Field, near Amman, Jordan; the passengers were held captive, and the planes were destroyed. The international hijacking crisis turned into a civil war, as the Jordanian government used force to restore its control of the country. See FAA report, Civil Aviation Reference Handbook, May 1999, appendix D.

The FAA knew or strongly suspected that Flight 11 was a hijacking 11 minutes after it was taken over; Flight 175, 9 minutes after it was taken over. There is no evidence to indicate that the FAA recognized Flight 77 as a hijacking until it crashed into the Pentagon.

67.  FAA audio file, Herndon Command Center, line 5114, 9:07:13; FAA audio file, Herndon Command Center, position 15, 9:19. At 9:07, Boston Air Traffic Control Center recommended to the FAA Command Center that a cockpit warning be sent to the pilots of all commercial aircraft to secure their cockpits. While Boston Center sent out such warnings to the commercial flights in its sector, we could find no evidence that a nationwide warning was issued by the ATC system.

68.  Ellen King interview (Apr. 5, 2004). FAA air traffic control tapes indicate that at 9:19 the FAA Air Traffic Control System Command Center in Herndon ordered controllers to send a cockpit warning to Delta 1989 because, like American 11 and United 175, it was a transcontinental flight departing Boston's Logan Airport.

69.  For American Airlines' response, see AAL briefing (Apr. 26, 2004). For Ballinger's warnings, see Ed Ballinger interview (Apr. 14, 2004). A companywide order for dispatchers to warn cockpits was not issued until 9:21. See UAL report, "Timeline: Dispatch/SMFDO Activities-Terrorist Crisis," undated. While one of Ballinger's colleagues assisted him, Ballinger remained responsible for multiple flights. See Ed Ballinger interview (Apr. 14, 2004). American Airlines' policy called for the flight dispatcher to manage only the hijacked flight, relieving him of responsibilities for all other flights. On American Airlines' policy, see Craig Marquis, Craig Parfitt, Joe Bertapelle, and Mike Mulcahy interview (Nov. 19, 2003). United Airlines had no such "isolation" policy. UAL System Operations Control briefing (Nov. 20, 2003).

70.  On FDR, see NTSB report, "Specialist's Factual Report of Investigation-Digital Flight Data Recorder" for United Airlines Flight 93, Feb. 15, 2002; on CVR, see FBI report, "CVR from UA Flight #93," Dec. 4, 2003; Commission review of Aircraft Communication and Reporting System (ACARS) messages sent to and from Flight 93 (which indicate time of message transmission and receipt); see UAL record, Ed Ballinger ACARS log, Sept. 11, 2001. At 9:22, after learning of the events at the World Trade Center, Melody Homer, the wife of co-pilot Leroy Homer, had an ACARS message sent to her husband in the cockpit asking if he was okay. See UAL record, ACARS message, Sept. 11, 2001.

71.  On FDR, see NTSB report, "Specialist's Factual Report of Investigation-Digital Flight Data Recorder" for United Airlines Flight 93, Feb. 15, 2002; on CVR, see FBI report, "CVR from UA Flight #93," Dec. 4, 2003; FAA report, "Summary of Air Traffic Hijack Events: September 11, 2001," Sept. 17, 2001; NTSB report, Air Traffic Control Recording-United Airlines Flight 93, Dec. 21, 2001.

72. The 37 passengers represented a load factor of 20.33 percent of the plane's seating capacity of 182, considerably below the 52.09 percent for Flight 93 on Tuesdays in the three-month period prior to September 11 (June 11-September 4, 2001). See UAL report, Flight 93 EWR-SFO load factors, undated. Five passengers holding reservations for Flight 93 did not show for the flight. All five were interviewed and cleared by the FBI. FBI report, "Flight #93 'No Show' Passengers from 9/11/01," Sept. 18, 2001.

73.  INS record, Withdrawal of Application for Admission for Mohamed al Kahtani, Aug. 4, 2001.

74.  See FAA regulations, Admission to flight deck, 14 C.F.R. � 121.547 (2001); UAL records, copies of boarding passes for United 93, Sept. 11, 2001. One passenger reported that ten first-class passengers were aboard the flight. If that number is accurate, it would include the four hijackers. FBI report of investigation, interview of Lisa Jefferson, Sept. 11, 2001; UAL record, Flight 93 passenger manifest, Sept. 11, 2001.All but one of the six passengers seated in the first-class cabin communicated with the ground during the flight, and none mentioned anyone from their cabin having gone into the cockpit before the hijacking. Moreover, it is unlikely that the highly regarded and experienced pilot and co-pilot of Flight 93 would have allowed an observer into the cockpit before or after takeoff who had not obtained the proper permission. See UAL records, personnel files of Flight 93 pilots. For jumpseat information, see UAL record, Weight and Balance Information for Flight 93 and Flight 175, Sept. 11, 2001;AAL records, Dispatch Environmental Control/Weekly Flight Summary for Flight 11 and Flight 77, Sept. 11, 2001.

75.  Like Atta on Flight 11, Jarrah apparently did not know how to operate the communication radios; thus his attempts to communicate with the passengers were broadcast on the ATC channel. See FBI report, "CVR from UA Flight #93," Dec. 4, 2003.Also, by 9:32 FAA notified United's headquarters that the flight was not responding to radio calls. According to United, the flight's nonresponse and its turn to the east led the airline to believe by 9:36 that the plane was hijacked. See Rich Miles interview (Nov. 21, 2003); UAL report, "United dispatch SMFDO activities-terrorist crisis," Sept. 11, 2001.

76.  In accordance with FAA regulations, United 93's cockpit voice recorder recorded the last 31 minutes of sounds from the cockpit via microphones in the pilots' headsets, as well as in the overhead panel of the flight deck. This is the only recorder from the four hijacked airplanes to survive the impact and ensuing fire. The CVRs and FDRs from American 11 and United 175 were not found, and the CVR from American Flight 77 was badly burned and not recoverable. See FBI report, "CVR from UA Flight #93,"Dec. 4, 2003; see also FAA regulations, 14 C.F.R. �� 25.1457, 91.609, 91.1045, 121.359; Flight 93 CVR data. A transcript of the CVR recording was prepared by the NTSB and the FBI.

77.  All calls placed on airphones were from the rear of the aircraft. There was one airphone installed in each row of seats on both sides of the aisle. The airphone system was capable of transmitting only eight calls at any one time. See FBI report of investigation, airphone records for flights UAL 93 and UAL 175 on Sept. 11, 2001, Sept. 18, 2001.

78.  FAA audio file, Cleveland Center, position Lorain Radar; Flight 93 CVR data; FBI report, "CVR from UA Flight #93," Dec. 4, 2003.

79.  FBI reports of investigation, interviews of recipients of calls from Todd Beamer, Sept. 11, 2001, through June 11, 2002; FBI reports of investigation, interviews of recipients of calls from Sandy Bradshaw, Sept. 11, 2001, through Oct. 4, 2001.Text messages warning the cockpit of Flight 93 were sent to the aircraft by Ed Ballinger at 9:24. See UAL record, Ed Ballinger's ACARS log, Sept. 11, 2001.

80. We have relied mainly on the record of FBI interviews with the people who received calls. The FBI interviews were conducted while memories were still fresh and were less likely to have been affected by reading the accounts of others or hearing stories in the media. In some cases we have conducted our own interviews to supplement or verify the record. See FBI reports of investigation, interviews of recipients of calls from Todd Beamer, Mark Bingham, Sandy Bradshaw, Marion Britton, Thomas Burnett, Joseph DeLuca, Edward Felt, Jeremy Glick, Lauren Grandcolas, Linda Gronlund, CeeCee Lyles, Honor Wainio.

81.  FBI reports of investigation, interviews of recipients of calls from Thomas Burnett, Sept. 11, 2001; FBI reports of investigation, interviews of recipients of calls from Marion Britton, Sept. 14, 2001, through Nov. 8, 2001; Lisa Jefferson interview (May 11, 2004); FBI report of investigation, interview of Lisa Jefferson, Sept. 11, 2001; Richard Belme interview (Nov. 21, 2003).

82.  See Jere Longman, Among the Heroes-United Flight 93 and the Passengers and Crew Who Fought Back (Harper-Collins, 2002), p. 107; Deena Burnett interview (Apr. 26, 2004); FBI reports of investigation, interviews of recipients of calls from Jeremy Glick, Sept. 11, 2001, through Sept. 12, 2001; Lyzbeth Glick interview (Apr. 22, 2004). Experts told us that a gunshot would definitely be audible on the CVR. The FBI found no evidence of a firearm at the crash site of Flight 93. See FBI response to Commission briefing request no. 6, undated (topic 11).The FBI collected 14 knives or portions of knives at the Flight 93 crash site. FBI report, "Knives Found at the UA Flight 93 Crash Site," undated.

83.  FBI response to Commission briefing request no. 6, undated (topic 11); FBI reports of investigation, interviews of recipients of calls from Jeremy Glick, Sept. 11, 2001, through Sept. 12, 2001.

84.  See FBI reports of investigation, interviews of recipients of calls from United 93.

85.  FBI reports of investigation, interviews of recipients of calls from United 93. For quote, see FBI report of investigation, interview of Philip Bradshaw, Sept. 11, 2001; Philip Bradshaw interview (June 15, 2004); Flight 93 FDR and CVR data. At 9:55:11 Jarrah dialed in the VHF Omni-directional Range (VOR) frequency for the VOR navigational aid at Washington Reagan National Airport, further indicating that the attack was planned for the nation's capital.

86.  Flight 93 FDR and CVR data.

87.  Ibid.

88.  Ibid.

89.  Ibid. The CVR clearly captured the words of the hijackers, including words in Arabic from the microphone in the pilot headset up to the end of the flight. The hijackers' statements, the clarity of the recording, the position of the microphone in the pilot headset, and the corresponding manipulations of flight controls provide the evidence. The quotes are taken from our listening to the CVR, aided by an Arabic speaker.

90.  In 1993, a Lufthansa aircraft was hijacked from its Frankfurt to Cairo route and diverted to JFK Airport in New York. The event lasted for 11 hours and was resolved without incident. Tamara Jones and John J. Goldman, "11-Hour Hijack Ends Without Injury in N.Y.,"Los Angeles Times, Feb. 12, 1993, p. A1.

91. The second half of the twentieth century witnessed a tremendous growth of the air transport industry, and the FAA's corresponding responsibilities grew enormously from the 1960s through 2001.Throughout that time, the FAA focused on setting and maintaining safety and efficiency standards. Since no plane had been hijacked inside the United States since 1991, sabotage was perceived as the most significant threat to civil aviation. For a broader discussion of the perception of the threat, see section 3.3.

92.  FAA report, "Administrator's Fact Book," July 2001; Benedict Sliney interview (May 21, 2004); John McCartney interview (Dec. 17, 2003).

93.  FAA regulations, Air Traffic Control transponder and altitude reporting equipment and use, 14 CFR � 91.215 (2001).

94.  DOD radar files, 84th Radar Evaluation Squadron, "9/11 Autoplay," undated; Charles Thomas interview (May 4, 2004); John Thomas interview (May 4, 2004); Joseph Cooper interview (Sept. 22, 2003);Tim Spence interview (Sept. 30, 2003). For general information on approaching terminals, see FAA report, "Aeronautical Information Manual," Feb. 19, 2004. Times assigned to audio transmissions were derived by the Commission from files provided by the FAA and the Northeast Air Defense Sector (NEADS) based on audio time stamps contained within the files provided by the sender. FAA tapes are certified accurate to Universal Coordinated Time by quality assurance specialists at FAA air traffic facilities. NEADS files are time-stamped as accurate to the Naval Observatory clock. We also compared audio times to certified transcripts when available.

95.  FAA Boston Center site visit (Sept. 22-24, 2003).

96.  NORAD's mission is set forth in a series of renewable agreements between the United States and Canada. According to the agreement in effect on 9/11, the "primary missions" of NORAD were "aerospace warning" and "aerospace control" for North America. Aerospace warning was defined as "the monitoring of man-made objects in space and the detection, validation, and warning of attack against North America whether by aircraft, missiles, or space vehicles." Aerospace control was defined as "providing surveillance and control of the airspace of Canada and the United States." See DOS memo, Exchange of Notes Between Canada and the United States Regarding Extension of the NORAD Agreement, Mar. 28, 1996; see also DOS press release,"Extension of NORAD Agreement," June 16, 2000 (regarding the extension of the 1996 Agreement unchanged). For NORAD's defining its job as defending against external attacks, see Ralph Eberhart interview (Mar. 1, 2004).

97.  DOD report,"NORAD Strategy Review: Final Report," July 1992, p. 55.

98.  For assumptions of exercise planners, see Paul Goddard and Ken Merchant interview (Mar. 4, 2004). For the authority to shoot down a commercial aircraft prior to 9/11, granted to NORAD but not used against Payne Stewart's plane in 1999 after the pilot and passengers lost consciousness, see Richard Myers interview (Feb. 17, 2004). A 1998 White House tabletop exercise chaired by Richard Clarke included a scenario in which a terrorist group loaded a Learjet with explosives and took off for a suicide mission to Washington. Military officials said they could scramble fighter jets from Langley Air Force Base to chase the aircraft, but they would need "executive" orders to shoot it down. Chuck Green interview (Apr. 21, 2004). For no recognition of this threat, see Ralph Eberhart interview (Mar. 1, 2004).

99.  Richard Myers interview (Feb. 17, 2004). 100. Donald Quenneville interview (Jan. 7, 2004); Langley Air Force Base 119th Fighter Wing briefing (Oct. 6-7, 2003).

101.  Collin Scoggins interviews (Sept. 22, 2003; Jan. 8, 2004); FAA report,"Crisis Management Handbook for Significant Events," Feb. 15, 2000; DOD memo, CJCS instruction,"Aircraft Piracy (Hijacking) and Destruction of Derelict Airborne Objects," June 1, 2001.

102.  See FAA regulations, Hijacked Aircraft, Order 7110.65M, para.10-2-6 (2001); David Bottiglia interview (Oct. 1, 2003); FAA report,"Crisis Management Handbook for Significant Events," Feb. 15, 2000. From interviews of controllers at various FAA centers, we learned that an air traffic controller's first response to an aircraft incident is to notify a supervisor, who then notifies the traffic management unit and the operations manager in charge.The FAA center next notifies the appropriate regional operations center (ROC), which in turn contacts FAA headquarters. Biggio stated that for American 11, the combination of three factors-loss of radio contact, loss of transponder signal, and course deviation-was serious enough for him to contact the ROC in Burlington, Mass. However, without hearing the threatening communication from the cockpit, he doubts Boston Center would have recognized or labeled American 11 "a hijack." Terry Biggio interview (Sept. 22, 2003); see also Shirley Miller interview (Mar. 30, 2004); Monte Belger interview (Apr. 20, 2004).

103.  FAA regulations, Special Military Operations, Requests for Service, Order 7610.4J, paras. 7-1-1, 7-1-2 (2001); DOD memo, CJCS instruction, "Aircraft Piracy (Hijacking) and Destruction of Derelict Airborne Objects," June 1, 2001.

104.  Ralph Eberhart interview (Mar. 1, 2004);Alan Scott interview (Feb. 4, 2004); Robert Marr interview (Jan. 23, 2004); FAA regulations, Position Reports within NORAD Radar Coverage, Order 7610.4J, para. 7-4-2 (2001); DOD memo, CJCS instruction,"Aircraft Piracy (Hijacking) and Destruction of Derelict Airborne Objects," June 1, 2001.

105.  FAA regulations,Air/Ground Communications Security, Order 7610.4J, para. 7-1-6 (2001); FAA regula-tions,Vectors, Order 7610.4J, para. 7-2-3 (2001).

106.  Peter Zalewski interview (Sept. 22, 2003); Terry Biggio interviews (Sept. 22, 2003; Jan. 8, 2004); Collin Scoggins interview (Sept. 22, 2003); Daniel Bueno interview (Sept. 22, 2003). For evidence of the numerous attempts by air traffic control to raise American 11, see FAA memo,"Full Transcript;Aircraft Accident;AAL11; New York, NY; September 11, 2001," Feb. 15, 2002, p. 7.

107.  DOD radar files, 84th Radar Evaluation Squadron, "9/11 Autoplay," undated; Peter Zalewski interview (Sept. 22, 2003); John Schippani interview (Sept. 22, 2003). 108. Peter Zalewski interview (Sept. 22, 2003); John Schippani interview (Sept. 22, 2003). 109. FAA memo,"Full Transcript;Aircraft Accident;AAL11; New York, NY; September 11, 2001," Feb. 15, 2002, p. 11; Peter Zalewski interview (Sept. 23, 2003). 110. Peter Zalewski interview (Sept. 23, 2003); John Schippani interview (Sept. 22, 2003);Terry Biggio interviews (Sept. 22, 2003; Jan. 8, 2004); Robert Jones interview (Sept. 22, 2003). 111. FAA memo,"Full Transcript;Aircraft Accident;AAL11; New York, NY; September 11, 2001,"Apr. 19, 2002, p. 2; FAA record, Boston Center daily record of facility operation, Sept. 11, 2001;Terry Biggio interviews (Sept. 22, 2003; Jan. 8, 2004); Daniel Bueno interview (Sept. 22, 2004). See also FAA memo,"Transcription of 9/11 Tapes," Oct. 2, 2003, p. 2; FAA audio file, Herndon Command Center, line 4525, 8:32-8:33.

112.  See FAA memo,"Transcription of 9/11 Tapes," Oct. 2, 2003, pp. 2-3; FAA record, New England Region Daily Log, Sept. 11, 2001; Daniel Bueno interview (Sept. 22, 2003);Terry Biggio interviews (Sept. 22, 2003; Jan. 8, 2004).

113.  FAA memo,"Full Transcript;Aircraft Accident;AAL11; New York, NY; September 11, 2001," Feb. 15, 2002, p. 12. 114. FAA memo,"Full Transcript;Aircraft Accident;AAL11; New York, NY; September 11, 2001," Jan. 28, 2002, p. 5. 115. FAA memo,"Full Transcript;Aircraft Accident;AAL11; New York, NY; September 11, 2001,"Apr. 19, 2002, p. 5;Terry Biggio interview (Sept. 22, 2003); Collin Scoggins interviews (Sept. 22, 2003; Jan. 8, 2004); Daniel Bueno interview (Sept. 22, 2003).

116.  On 9/11, NORAD was scheduled to conduct a military exercise,Vigilant Guardian, which postulated a bomber attack from the former Soviet Union. We investigated whether military preparations for the large-scale exercise compromised the military's response to the real-world terrorist attack on 9/11. According to General Eber-hart,"it took about 30 seconds" to make the adjustment to the real-world situation. Ralph Eberhart testimony, June 17, 2004.We found that the response was, if anything, expedited by the increased number of staff at the sectors and at NORAD because of the scheduled exercise. See Robert Marr interview (Jan. 23, 2004).

117.  For the distance between Otis Air Force Base and New York City, see William Scott testimony, May 23, 2003. For the order from NEADS to Otis to place F-15s at battle stations, see NEADS audio file,Weapons Director Technician position, channel 14, 8:37:15. See also interviews with Otis and NEADS personnel: Jeremy Powell interview (Oct. 27, 2003); Michael Kelly interview (Oct. 14, 2003); Donald Quenneville interview (Jan. 7, 2004), and interviews with Otis fighter pilots: Daniel Nash interview (Oct. 14, 2003); Timothy Duffy interview (Jan. 7, 2004). According to Joseph Cooper from Boston Center,"I coordinated with Huntress ["Huntress" is the call sign for NEADS]. I advised Huntress we had a hijacked aircraft. I requested some assistance. Huntress requested and I supplied pertinent information. I was advised aircraft might be sent from Otis." FAA record, Personnel Statement of Joseph Cooper, Oct. 30, 2001.

118.  Robert Marr interview (Jan. 23, 2004); Leslie Filson, Air War Over America (First Air Force, 2003), p. 56; Larry Arnold interview (Feb. 3, 2004).

119.  NEADS audio file, Weapons Director Technician position, channel 14; 8:45:54; Daniel Nash interview (Oct. 14, 2003); Michael Kelly interview (Oct. 14, 2003); Donald Quenneville interview (Jan. 7, 2004); Timothy Duffy interview (Jan. 7, 2004); NEADS audio file, Mission Crew Commander position, channel 2, 8:44:58; NEADS audio file, Identification Technician position, channel 5, 8:51:13.

120.  FAA audio file, Boston Center, position 31R; NEADS audio file, Mission Crew Commander position, channel 2, 8:58:00; NEADS audio file, Mission Crew Commander position, channel 2, 8:54:55. Because of a technical issue, there are no NEADS recordings available of the NEADS senior weapons director and weapons director technician position responsible for controlling the Otis scramble.We found a single communication from the weapons director or his technician on the Guard frequency at approximately 9:11, cautioning the Otis fighters: "remain at current position [holding pattern] until FAA requests assistance." See NEADS audio file, channel 24. That corresponds to the time after the Otis fighters entered the holding pattern and before they headed for New York. NEADS controllers were simultaneously working with a tanker to relocate close to the Otis fighters.At 9:10, the senior director on the NEADS floor told the weapons director,"I want those fighters closer in." NEADS audio file, Identification Technician position, channel 5. At 9:10:22, the Otis fighters were told by Boston Center that the second tower had been struck. At 9:12:54, the Otis fighters told their Boston Center controller that they needed to establish a combat air patrol over New York, and they immediately headed for New York City. See FAA audio files, Boston Center, position 31R. This series of communications explains why the Otis fighters briefly entered and then soon departed the holding pattern, as the radar reconstruction of their flight shows. DOD radar files, 84th Radar Evaluation Squadron,"9/11 Autoplay," undated.

121.  In response to allegations that NORAD responded more quickly to the October 25, 1999, plane crash that killed Payne Stewart than it did to the hijacking of American 11, we compared NORAD's response time for each incident.The last normal transmission from the Stewart flight was at 9:27:10 A.M. Eastern Daylight Time. The Southeast Air Defense Sector was notified of the event at 9:55, 28 minutes later. In the case of American 11, the last normal communication from the plane was at 8:13 A.M. EDT. NEADS was notified at 8:38, 25 minutes later. We have concluded there is no significant difference in NORAD's reaction to the two incidents. See NTSB memo, Aircraft Accident Brief for Payne Stewart incident, Oct. 25, 1999; FAA email, Gahris to Myers,"ZJX Timeline for N47BA accident," Feb. 17, 2004.

122.  FAA memo, "Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001," May 8, 2002, pp. 5-6.

123.  FAA audio file, New York Center, position R42, 8:42-8:45; FAA memo, "Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001," May 8, 2002, pp. 6-8; DOD radar files, 84th Radar Evaluation Squadron,"9/11 Autoplay," undated.The FAA-produced timeline notes,"Based on coordination received from [Boston Center] indicating a possible hijack, most of the controller's attention is focused on AAL 11." See FAA report,"Summary of Air Traffic Hijack Events September 11, 2001," Sept. 17, 2001; see also David Bottiglia interview (Oct. 1, 2003); FAA memo,"Full Transcript;Aircraft Accident; UAL175; New York, NY; September 11, 2001," May 8, 2002, p. 9.

124.  FAA audio file, Herndon Command Center, New York Center position, line 5114, 8:48.

125.  FAA memo, "Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001," May 8, 2002, pp. 12, 14.

126.  Ibid., p. 15.At 8:57, the following exchange between controllers occurred:"I got some handoffs for you. We got some incidents going over here. Is Delta 2433 going to be okay at thirty-three? I had to climb him for traffic. I let you United 175 just took off out of think we might have a hijack over here.Two of them." See FAA memo, "Full Transcript;Aircraft Accident; UAL175; New York, NY; September 11, 2001," May 8, 2002.

127.  See FAA report,"Summary of Air Traffic Hijack Events September 11, 2001," Sept. 17, 2001; Evanna Dowis interview (Sept. 30, 2004); Michael McCormick interview (Dec. 15, 2003); FAA record, Personnel Statement of Michael McCormick, Oct. 17, 2001. See also FAA memo,"Full Transcript;Aircraft Accident; UAL175; New York, NY; September 11, 2001," May 8, 2002, p. 17.

128.  FAA memo,"Full Transcript; Command Center; NOM Operational Position; September 11, 2001," Oct. 14, 2003, pp. 15-17.

129.  FAA memo, "Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001," Jan. 17, 2002, p. 3.

130. "N90 [New York Terminal Radar Approach] controller stated 'at approximately 9:00 a.m., I observed an unknown aircraft south of the Newark, New Jersey Airport, northeast bound and descending out of twelve thousand nine hundred feet in a rapid rate of descent, the radar target terminated at the World Trade Center.'" FAA report,"Summary of Air Traffic Hijack Events September 11, 2001,"Sept. 17, 2001. Former NORAD official Alan Scott testified that the time of impact of United 175 was 9:02. William Scott testimony, May 23, 2003. We have determined that the impact time was 9:03:11 based on our analysis of FAA radar data and air traffic control software logic.

131.  FAA audio file, Herndon Command Center, New York Center position, line 5114, 9:02:34.

132.  Ibid., 9:03; FAA audio file, Herndon Command Center, Cleveland/Boston position, line 5115, 9:05; Michael McCormick interview (Oct. 1, 2003); David LaCates interview (Oct. 2, 2003).

133.  FAA Audio File, Herndon Command Center, Boston Center position, line 5115, 9:05-9:07.

134.  Joseph McCain interview (Oct. 28, 2003); Robert Marr (Jan. 23, 2004); James Fox interview (Oct. 29, 2003); Dawne Deskins interview (Oct. 30, 2003).

135.  NEADS audio file, Mission Crew Commander position, channel 2, 9:07:32.

136.  Daniel Nash interview (Oct. 14, 2003);Timothy Duffy interview (Jan. 7, 2004).

137.  Because the Otis fighters had expended a great deal of fuel in flying first to military airspace and then to New York, the battle commanders were concerned about refueling. As NEADS personnel looked for refueling tankers in the vicinity of New York, the mission crew commander considered scrambling the Langley fighters to New York to provide backup for the Otis fighters until the NEADS Battle Cab (the command area that overlooks the operations floor) ordered "battle stations only at Langley." The alert fighters at Langley Air Force Base were ordered to battle stations at 9:09. Colonel Marr, the battle commander at NEADS, and General Arnold, the CONR commander, both recall that the planes were held on battle stations, as opposed to scrambling, because they might be called on to relieve the Otis fighters over New York City if a refueling tanker was not located, and also because of the general uncertainty of the situation in the sky.According to William Scott at the Commission's May 23, 2003, hearing,"At 9:09, Langley F-16s are directed to battle stations, just based on the general situation and the breaking news, and the general developing feeling about what's going on." See NEADS audio file, Mission Crew Commander, channel 2, 9:08:36; Robert Marr interview (Oct. 27, 2003); Larry Arnold interview (Feb. 3, 2004). See also Colonel Marr's statement that "[t]he plan was to protect New York City." Filson, Air War Over America,p.60.

138.  Commission analysis of FAA radar data and air traffic control transmissions.

139. The Indianapolis Center controller advised other Indianapolis Center personnel of the developing situa-tion.They agreed to "sterilize" the airspace along the flight's westerly route so the safety of other planes would not be affected. John Thomas interview (May 4, 2004).

140.  John Thomas interview (Sept. 24, 2003). According to the FAA-produced timeline, at 9:09 Indianapolis Center "notified Great Lakes Regional Operations Center a possible aircraft accident of AMERICAN 77 due to the simultaneous loss of radio communications and radar identification." FAA report,"Summary of Air Traffic Hijack Events September 11, 2001," Sept. 17, 2001.

141.  FAA audio file, Herndon Command Center, National Operations Manager position, line 4525; FAA audio file, Herndon Command Center, National Traffic Management Officer east position, line 4530; FAA memo,"Full Transcription; Air Traffic Control System Command Center, National Traffic Management Officer, East Position; September 11, 2001," Oct. 21, 2003, p. 13.

142.  Primary radar contact for Flight 77 was lost because the "preferred" radar in this geographic area had no primary radar system, the "supplemental" radar had poor primary coverage, and the FAA ATC software did not allow the display of primary radar data from the "tertiary" and "quadrary" radars.

143.  David Boone interview (May 4, 2004); Charles Thomas interview (May 4, 2004); John Thomas interview (May 4, 2004); Commission analysis of FAA radar data and air traffic control software logic.

144.  John Thomas interview (May 4, 2004); Charles Thomas interview (May 4, 2004). We have reviewed all FAA documents, transcripts, and tape recordings related to American 77 and have found no evidence that FAA headquarters issued a directive to surrounding centers to search for primary radar targets. Review of the same materials also indicates that no one within FAA located American 77 until the aircraft was identified by Dulles controllers at 9:32. For much of that time, American 77 was traveling through Washington Center's airspace. The Washington Center's controllers were looking for the flight, but they were not told to look for primary radar returns.

145.  John White interview (May 7, 2004); Ellen King interview (Apr. 5, 2004); Linda Schuessler interview (Apr. 6, 2004); Benedict Sliney interview (May 21, 2004); FAA memo, "Full Transcription; Air Traffic Control System Command Center, National Traffic Management Officer, East Position; September 11, 2001," Oct. 21, 2003, pp. 14, 27.

146.  John Hendershot interview (Dec. 22, 2003).

147.  FAA memo, "Partial Transcript; Aircraft Accident; AAL77; Washington, DC; September 11, 2001," Sept. 20, 2001, p. 7.

148.  NEADS audio file, Identification Technician position, channel 7, 9:21:10.

149.  NEADS audio file, Mission Crew Commander, channel 2, 9:21:50; Kevin Nasypany interview (Jan. 22-23, 2004).

150.  NEADS audio file, Mission Crew Commander, Channel 2, 9:22:34.The mission commander thought to put the Langley scramble over Baltimore and place a "barrier cap" between the hijack and Washington, D.C. Kevin Nasypany interview (Jan. 22-23, 2004).

151.  NEADS audio file, Identification Technician position, channel 5, 9:32:10; ibid., 9:33:58.

152.  For first quote, see NEADS audio file, Identification Technician position, channel 5, 9:35:50. For second quote, see NEADS audio file, Identification Technician position,channel 7, 9:36:34; Kevin Nasypany interview (Jan. 22-23, 2004). For the third quote, see NEADS audio file, Mission Crew Commander, channel 2, 9:39; 9:39:37; Kevin Nasypany interview (Jan. 22-23, 2004).

153.  Dean Eckmann interview (Dec. 1, 2003); FAA memo,"Partial Transcript; Scramble Aircraft; QUIT25; September 11, 2001," Sept. 4, 2003, pp. 2-4 (Peninsular Radar position); FAA memo,"Partial Transcript; Scramble Aircraft; QUIT25; September 11, 2001," Sept. 4, 2003, pp. 2-5 (East Feeder Radar position).

154.  NEADS audio file, Mission Crew Commander, channel 2, 9:38:02; Dawne Deskins interview (Oct. 30, 2003).The estimated time of impact of Flight 77 into the Pentagon is based on Commission analysis of FDR, air traffic control, radar, and Pentagon elevation and impact site data.

155.  Joseph Cooper interview (Sept. 22, 2003); NEADS audio file, Identification Technician position, recorder 1, channel 7, 9:41.

156.  NEADS audio file, Mission Crew Commander position, channel 2, 9:42:08.

157.  FAA memo, "Full Transcript; Aircraft Accident; N591UA (UAL93); Somerset, PA; September 11, 2001," May 10, 2002, p. 10.

158. The United 93 timeline in FAA report,"Summary of Air Traffic Hijack Events September 11, 2001," Sept. 17, 2001, states that at 9:28:17 "a radio transmission of unintelligible sounds of possible screaming or a struggle from an unknown origin was heard over the ZOB [Cleveland Center] radio." See FAA memo,"Full Transcript;Aircraft Accident; N591UA (UAL93); Somerset, PA; September 11, 2001," May 10, 2002, p. 11.

159. The United 93 timeline in FAA report,"Summary of Air Traffic Hijack Events September 11, 2001," Sept. 17, 2001, states that at 9:28:54 a "second radio transmission, mostly unintelligible, again with sounds of possible screaming or a struggle and a statement,'get out of here, get out of here' from an unknown origin was heard over the ZOB [Cleveland Center] radio." FAA audio file, Cleveland Center, Lorain Radar position; FAA memo, "Full Transcript; Aircraft Accident; N591UA (UAL93); Somerset, PA; September 11, 2001," May 10, 2002, p. 11. At 9:31:48, ExecJet 56 also called in, reporting that "we're just answering your call.We did hear that, uh, yelling too." The FAA responded at 9:31:51,"Okay, thanks.We're just trying to figure out what's going on." FAA memo,"Full Transcript;Aircraft Accident; N591UA (UAL93); Somerset, PA; September 11, 2001," May 10, 2002, p. 15.

160.  FAA memo, "Full Transcript; Aircraft Accident; N591UA (UAL93); Somerset, PA; September 11, 2001," May 10, 2002, p. 15.

161.  FAA memo,"Full Transcription;Air Traffic Control System Command Center, National Traffic Management Officer, East Position; September 11, 2001," Oct. 21, 2003, pp. 10, 13; FAA audio file, Herndon Command Center, New York Center position, line 5154.

162.  FAA memo, "Full Transcript; Aircraft Accident; N591UA (UAL93); Somerset, PA; September 11, 2001," May 10, 2002, p. 19.

163.  Ibid., p. 23.

164.  FAA memo,"Full Transcription;Air Traffic Control System Command Center, National Traffic Management Officer, East Position; September 11, 2001," Oct. 21, 2003, pp. 16-17; FAA audio file, Cleveland Center, Lorain Radar position; FAA memo, "Full Transcript; Aircraft Accident; N591UA (UAL93); Somerset, PA; September 11, 2001," May 10, 2002, pp. 26-32.

165.  FAA memo,"Full Transcription;Air Traffic Control System Command Center, National Traffic Management Officer, East Position; September 11, 2001," Oct. 21, 2003, pp. 17-19.

166.  For 9:46 quotation, see ibid., pp. 19-20. For 9:49 discussion about military assistance, see ibid., p. 21.

167.  For 9:53 discussion about scrambling aircraft, see ibid., p. 23. Neither Monte Belger nor the deputy director for air traffic services could recall this discussion in their interviews with us. Monte Belger interview (Apr. 20, 2004); Peter Challan interview (Mar. 26, 2004). Subsequently Belger told us he does not believe the conversation occurred. Monte Belger, email to the Commission, July 12, 2004. However, tapes from the morning reveal that at

9:53 a staff person from headquarters told the Command Center "Peter's talking to Monte now about scrambling." FAA memo,"Full Transcription;Air Traffic Control System Command Center, National Traffic Management Officer, East Position; September 11, 2001," Oct. 21, 2003, p. 23. For discussions about the status of United 93, see ibid., pp. 24-27.

168.  Ibid., pp. 23-27.We also reviewed a report regarding seismic observations on September 11, 2001, whose authors conclude that the impact time of United 93 was "10:06:05�5 (EDT)."Won-Young Kim and G. R. Baum, "Seismic Observations during September 11, 2001,Terrorist Attack," spring 2002 (report to the Maryland Department of Natural Resources). But the seismic data on which they based this estimate are far too weak in signal-to-noise ratio and far too speculative in terms of signal source to be used as a means of contradicting the impact time established by the very accurate combination of FDR, CVR, ATC, radar, and impact site data sets.These data sets constrain United 93's impact time to within 1 second, are airplane- and crash-site specific, and are based on time codes automatically recorded in the ATC audiotapes for the FAA centers and correlated with each data set in a process internationally accepted within the aviation accident investigation community. Furthermore, one of the study's principal authors now concedes that "seismic data is not definitive for the impact of UA 93." Email from Won-Young Kim to the Commission,"Re: UA Flight 93,"July 7, 2004; see also Won-Young Kim,"Seismic Observations for UA Flight 93 Crash near Shanksville, Pennsylvania during September 11, 2001," July 5, 2004.

169.  FAA memo,"Full Transcription;Air Traffic Control System Command Center, National Traffic Management Officer, East Position; September 11, 2001," Oct. 21, 2003, p. 31.

170.  For 10:17 discussion, see ibid., p. 34. For communication regarding "black smoke," see FAA memo,"Full Transcript; Aircraft Accident; N591UA (UAL93) Somerset, PA; September 11, 2001," May 10, 2002, pp. 16-18 (Cleveland Center, Imperial Radar position).This report from the C-130H was recorded on ATC audio about 1 minute and 37 seconds after the impact time of United 93 as established by NTSB and Commission analysis of FDR, CVR, radar, and impact data sets-more than a minute before the earliest impact time originally posited by the authors of the seismic data report.

171.  NEADS audio file, Identification Technician, channel 5, 10:07.

172.  NEADS audio file, Mission Crew Commander, channel 2, 10:10.

173.  NEADS audio file, Identification Technician, channel 4, 10:14.

174.  DOD record, NEADS MCC/T Log Book, Sept. 11, 2001.

175. William Scott testimony, May 23, 2003.

176.  Larry Arnold testimony, May 23, 2003.

177.  See DOD record, NEADS MCC/T Log Book, Sept. 11, 2001.The entry in this NEADS log records the tail number not of American 77 but of American 11:"American Airlines #N334AA hijacked." See also DOD record, Surveillance Log Book, Sept. 11, 2001.

178. William Scott testimony, May 23, 2003; DOD briefing materials,"Noble Eagle; 9-11 Timeline," undated.

179.  For lack of knowledge about the hijacking, see, e.g.,White House transcript, Card interview with Ron Fournier of the Associated Press, Aug. 7, 2002. For information on the hijacking within the FAA, see the discussion of American 11 in section 1.2.

180.  See White House record, Situation Room Log, Sept. 11, 2001;White House record, Presidential Emergency Operations Center (PEOC) Watch Log, Sept. 11, 2001; DOD record, Senior Operations Officer log, Sept. 11, 2001.

181.  Jane Garvey interview (Jun. 30, 2004); Monte Belger interview (Apr. 20, 2004).

182.  For notifications, see DOD record, Assistant Deputy Director Operations Passdown Log, Sept. 11, 2001. For the call to the FAA, see DOD record, Senior Operations Officer log, Sept. 11, 2001 ("9:00 NMCC called FAA, briefed of explosion at WTC possibly from aircraft crash.Also, hijacking of American Flight 11 from Boston to LA, now enroute to Kennedy"). For the scrambling of jets not being discussed, see Ryan Gonsalves interview (May 14, 2004).

183.  Secret Service records show the motorcade arriving between 8:50 and 8:55. USSS record, shift log, Sept. 11, 2001 (8:55); USSS record, Command Post Protectee Log, Sept. 11, 2001 (8:50). For Andrew Card's recollection, see Andrew Card meeting (Mar. 31, 2004). For the President's reaction, see Andrew Card meeting (Mar. 31, 2004);White House transcript, President Bush interview with Bob Schieffer of CBS News, Apr. 17, 2002.

184. White House transcript, Rice interview with Evan Thomas of Newsweek, Nov. 1, 2001, p. 2; see also White House record, President's Daily Diary, Sept. 11, 2001.

185. White House transcript,Vice President Cheney interview with Newsweek, Nov. 19, 2001, p. 1.

186.  For Rice's meeting, see White House transcript, Rice interview with Bob Woodward of the Washington Post, Oct. 24, 2001, pp. 360-361. For White House staff monitoring the news, see, e.g., White House transcript, Rice interview with Evan Thomas, Nov. 11, 2001, p. 388.

187.  On White House staff reaction, see White House transcript, Rice interview with Bob Woodward, Oct. 24, 2001, p. 361; Andrew Card meeting (Mar. 31, 2004). On security enhancements, see USSS memo, interview with Carl Truscott, Oct. 1, 2001, p. 1. On security measures being precautionary, see Carl Truscott interview (Apr. 15, 2004).

188.  For the time of the teleconference, see FAA record, Chronology ADA-30, Sept. 11, 2001. For recollections of the NMCC officer, see Charles Chambers interview (Apr. 23, 2004). For recollections of the FAA manager, see Michael Weikert interview (May 7, 2004). For Belger's reaction, see Monte Belger testimony, June 17, 2004.

189.  For the times of the video teleconference, see White House record, Situation Room Communications Log, Sept. 11, 2001 (9:25 start); CIA notes, Cofer Black timeline, Sept. 11, 2001 (CIA representatives joining at 9:40); FAA record, Chronology ADA-30, Sept. 11, 2001 (FAA representatives joining at 9:40).

190.  Patrick Gardner interview (May 12, 2004). For participants, see Jane Garvey interview (Oct. 21, 2003); Monte Belger interview (Apr. 20, 2004); Jeff Griffith interview (Mar. 31, 2004). On the absence of Defense officials, see John Brunderman interview (May 17, 2004).The White House video teleconference was not connected into the area of the NMCC where the crisis was being managed.Thus the director of the operations team-who was on the phone with NORAD-did not have the benefit of information being shared on the video teleconference. See, e.g., Charles Leidig interview (Apr. 29, 2004); Montague Winfield interview (Apr. 26, 2004); Patrick Gardner interview (May 12, 2004). Moreover, when the Secretary and Vice Chairman later participated in the White House video teleconference, they were necessarily absent from the NMCC and unable to provide guidance to the operations team. See DOD report, OT-2 Analysis of NMCC Response to Terrorist Attack on 11 SEP 01, Oct. 4, 2001; John Brunderman interview (May 17, 2004).

191.  NSC notes, Paul Kurtz notes, Sept. 11, 2001; Paul Kurtz meeting (Dec. 22, 2003). For shootdown authority having already been conveyed, see DOD transcript, Air Threat Conference Call, Sept. 11, 2001.

192.  Charles Leidig interview (Apr. 29, 2004). For the job of the NMCC in an emergency, see NMCC briefing (July 21, 2003).

193.  For the Secretary's activities, see DOD memo, interview of Donald Rumsfeld, Dec. 23, 2002; Stephen Cambone interview (July 8, 2004).

194.  Charles Leidig interview (Apr. 29, 2004). Secure teleconferences are the NMCC's primary means of coordinating emergencies, and they fall into two categories:"event" and "threat." Event conferences seek to gather information. If the situation escalates, a threat conference may be convened. On 9/11, there was no preset teleconference for a domestic terrorist attack. NMCC and National Military Joint Intelligence Center (NMJIC) briefing (July 21, 2003). For the content of the conferences on 9/11, see DOD transcript,Air Threat Conference Call, Sept. 11, 2001.

195.  See DOD transcript, Air Threat Conference Call, Sept. 11, 2001; see also White House notes, Thomas Gould notes, Sept. 11, 2001.

196.  On difficulties in including the FAA, see NMCC and NMJIC briefing (July 21, 2003); John Brunderman interview (May 17, 2004). On NORAD and the time of the FAA's joining, see DOD transcript, Air Threat Conference Call, Sept. 11, 2001. For the FAA representative, see Rayford Brooks interview (Apr. 15, 2004).

197.  Richard Myers interview (Feb. 17, 2004); Charles Leidig interview (Apr. 29, 2004).

198.  DOD transcript, Air Threat Conference Call, Sept. 11, 2001.

199.  On the briefing, see ibid.The Vice Chairman was on Capitol Hill when the Pentagon was struck, and he saw smoke as his car made its way back to the building. Richard Myers interview (Feb. 17, 2004). For the Chairman being out of the country, see DOD record, Deputy Director for Operations Passdown Log, Sept. 11, 2001.

200.  DOD transcript, Air Threat Conference Call, Sept. 11, 2001.

201.  Ibid.

202.  Ibid.

203.  For the President being informed at 9:05, see White House record, President's Daily Diary, Sept. 11, 2001. For Card's statement, see White House transcript, Card interview with Ron Fournier, Aug. 7, 2002. For the Pres-ident's reaction, see President Bush and Vice President Cheney meeting (Apr. 29, 2004).

204.  For the President's activities, see Education Channel videotape,"Raw Footage of President Bush at Emma E. Booker Elementary School," Sept. 11, 2001 (remaining in classroom); Deborah Loewer meeting (Feb. 6, 2004) (in the holding room). For his calls, see White House record, President's Daily Diary, Sept. 11, 2001 (9:15 call to Vice President); Deborah Loewer meeting (Feb. 6, 2004) (call to Rice); President Bush and Vice President Cheney meeting (Apr. 29, 2004) (call to Pataki); White House record, Secure Switchboard Log, Sept. 11, 2001 (call to Mueller). For the decision to make a statement, see Ari Fleischer interview (Apr. 22, 2004). For the Secret Service's perspective, see Edward Marinzel interview (Apr. 21, 2004).

205.  On the return to Washington, see Deborah Loewer meeting (Feb. 6, 2004); Andrew Card meeting (Mar. 31, 2004). On consulting with senior advisers, see Ari Fleischer interview (Apr. 22, 2004). On information about additional aircraft, see, e.g., Andrew Card meeting (Mar. 31, 2004). On decisions and the focus on the President's speech, see President Bush and Vice President Cheney meeting (Apr. 29, 2004); Ari Fleischer interview (Apr. 22, 2004); Andrew Card meeting (Mar. 31, 2004).

206.  On the motorcade, see USSS record, shift log, Sept. 11, 2001 (departing 9:35, arriving 9:45); USSS record, Command Post Protectee Log, Sept. 11, 2001 (departing 9:36, arriving 9:42). Fleischer deduced from his notes that the President learned about the Pentagon while in the motorcade.Ari Fleischer interview (Apr. 22, 2004). For the President's actions and statements to the Vice President, see Ari Fleischer interview (Apr. 22, 2004);White House notes, Ari Fleischer notes, Sept. 11, 2001.

207.  On not returning to Washington, see Edward Marinzel interview (Apr. 21, 2004); USSS memo, interview of Edward Marinzel, Oct. 3, 2001;Andrew Card meeting (Mar. 31, 2004). For additional sources on the President's desire to return, see White House transcript,Vice President Cheney interview with Newsweek, Nov. 19, 2001, p. 5. For the Vice President's recollection, see President Bush and Vice President Cheney meeting (Apr. 29, 2004). For time of departure, see USSS record, Command Post Protectee Log, Sept. 11, 2001. On Air Force One's objectives on takeoff, see Edward Marinzel interview (Apr. 21, 2004).

208.  USSS memo, interview of Gregory LaDow, Oct. 1, 2001, p. 1. Shortly after the second attack in New York, a senior Secret Service agent charged with coordinating the President's movements established an open line with his counterpart at the FAA, who soon told him that there were more planes unaccounted for-possibly hijacked- in addition to the two that had already crashed.Though the senior agent told someone to convey this information to the Secret Service's operations center, it either was not passed on or was passed on but not disseminated; it failed to reach agents assigned to the Vice President, and the Vice President was not evacuated at that time. See Nelson Garabito interview (Mar. 11, 2004); USSS memo, interview of Nelson Garabito, Oct. 1, 2001; see also Terry Van Steenbergen interview (Mar. 30, 2004).

209.  American 77's route has been determined through Commission analysis of FAA and military radar data. For the evacuation of the Vice President, see White House transcript, Vice President Cheney interview with Newsweek, Nov. 19, 2001, p. 2; USSS memo, interview of Rocco Delmonico, Oct. 1, 2001 (evacuation of the White House); see also White House notes, Mary Matalin notes, Sept. 11, 2001. On the time of entering the tunnel, see USSS report,"Executive Summary: U.S. Secret Service Timeline of Events, September 11-October 3, 2001," Oct. 3, 2001, p. 2. Secret Service personnel told us that the 9:37 entry time in their timeline was based on alarm data, which is no longer retrievable. USSS briefing (Jan. 29, 2004).

210. White House transcript,Vice President Cheney interview with Newsweek, Nov. 19, 2001, p. 4; President Bush and Vice President Cheney meeting (Apr. 29, 2004).

211.  On Mrs. Cheney, see USSS report, "Executive Summary: U.S. Secret Service Timeline of Events, September 11-October 3, 2001," Oct. 3, 2001, p. 2 (time of arrival);White House transcript, Lynne Cheney interview with Newsweek, Nov. 9, 2001, p. 2 (joining the Vice President). For the contemporaneous notes, see White House notes, Lynne Cheney notes, Sept. 11, 2001. On the content of the Vice President's call, see White House transcript,Vice President Cheney interview with Newsweek, Nov. 19, 2001, p. 5.According to the Vice President, there was "one phone call from the tunnel. And basically I called to let him know that we were a target and I strongly urged him not to return to Washington right away, that he delay his return until we could find out what the hell was going on." For their subsequent movements, see White House transcript,Vice President Cheney interview with Newsweek, Nov. 19, 2001, p. 5;White House transcript, Lynne Cheney interview with Newsweek,Nov. 9, 2001, p. 2.

212.  On communications problems, see, e.g., President Bush and Vice President Cheney meeting (Apr. 29, 2004). On lack of an open line, see, e.g., Deborah Loewer meeting (Feb. 6, 2004).

213.  On the Vice President's call, see President Bush and Vice President Cheney meeting (Apr. 29, 2004). For the Vice President's time of arrival in the shelter conference room, see White House record, PEOC Shelter Log, Sept. 11, 2001 (9:58); USSS memo, OVP 9/11 Timeline, Nov. 17, 2001 (9:52; Mrs. Cheney arrived White House and joined him in tunnel);White House notes, Lynne Cheney notes (9:55; he is on phone with President);White House transcript, Lynne Cheney interview with Newsweek, Nov. 9, 2001, p. 2 ("And when I got there, he was on the phone with the President . . . But from that first place where I ran into him, I moved with him into what they call the PEOC"); White House transcript,Vice President Cheney interview with Newsweek, Nov. 19, 2001, p. 4

(9:35 or 9:36 arrival; he estimated a 15-minute stay); Carl Truscott interview (Apr. 15, 2004) (arrived with Rice and the Vice President in conference room; called headquarters immediately; call logged at 10:00); President Bush and Vice President Cheney meeting,Apr. 29, 2004 (Vice President viewed television footage of Pentagon ablaze in tunnel);White House transcript, Rice interview with Evan Thomas, Nov. 1, 2001, p. 388 (Rice viewed television footage of Pentagon ablaze in Situation Room). For the Vice President's recollection about the combat air patrol, see President Bush and Vice President Cheney meeting (Apr. 29, 2004); White House transcript, President Bush interview with Bob Woodward and Dan Balz, Dec. 17, 2001, p. 16.

214.  President Bush and Vice President Cheney meeting (Apr. 29, 2004); see also White House transcript,Vice President Cheney interview with Newsweek, Nov. 19, 2001, pp. 7-8.

215.  Douglas Cochrane meeting (Apr. 16, 2004); Condeleeza Rice meeting (Feb. 7, 2004). For Rice entering after the Vice President, see USSS report,"Executive Summary: U.S. Secret Service Timeline of Events, September 11-October 3, 2001," Oct. 3, 2001, p. 2; Carl Truscott interview (Apr. 15, 2004).

216.  In reconstructing events that occurred in the PEOC on the morning of 9/11, we relied on (1) phone logs of the White House switchboard; (2) notes of Lewis Libby, Mrs. Cheney, and Ari Fleischer; (3) the tape (and then transcript) of the air threat conference call; and (4) Secret Service and White House Situation Room logs, as well as four separate White House Military Office logs (the PEOC Watch Log, the PEOC Shelter Log, the Communications Log, and the 9/11 Log).

217.  DOD transcript, Air Threat Conference Call, Sept. 11, 2001. For one open line between the Secret Service and the FAA, see note 208. At Secret Service headquarters, personnel from the intelligence division were also on a phone conference with FAA headquarters. Chuck Green interview (Mar. 10, 2004). For notification of an inbound aircraft at 10:02, see USSS record, Intelligence Division timeline, Sept. 11, 2001; USSS record, Crisis Center Incident Monitor, Sept. 11, 2001. For the FAA's projection, see Tim Grovack interview (Apr. 8, 2004). For Secret Service updates, see DOD transcript, Air Threat Conference Call, Sept. 11, 2001.

218. White House notes, Lynne Cheney notes, Sept. 11, 2001;White House notes, Lewis Libby notes, Sept. 11, 2001.

219.  For Libby's characterization, see White House transcript, Scooter Libby interview with Newsweek, Nov. 2001. For the Vice President's statement, see President Bush and Vice President Cheney meeting (Apr. 29, 2004). For the second authorization, see White House notes, Lynne Cheney notes, Sept. 11, 2001; White House notes, Lewis Libby notes, Sept. 11, 2001.

220.  Joshua Bolten meeting (Mar. 18, 2004); see also White House notes, Lewis Libby notes, Sept. 11, 2001 ("10:15-18:Aircraft 60 miles out, confirmed as hijack-engage? VP:Yes. JB [Joshua Bolten]: Get President and confirm engage order").

221.  For the Vice President's call, see White House record, Secure Switchboard Log, Sept. 11, 2001;White House record, President's Daily Diary, Sept. 11, 2001; White House notes, Lewis Libby notes, Sept. 11, 2001. Fleischer's

10:20 note is the first mention of shootdown authority. See White House notes,Ari Fleischer notes, Sept. 11, 2001;

see also Ari Fleischer interview (Apr. 22, 2004).

222.  DOD transcript, Air Threat Conference Call, Sept. 11, 2001.

223.  On reports of another plane, see White House notes, Lynne Cheney notes, Sept. 11, 2001;White House notes, Lewis Libby notes, Sept. 11, 2001. On the Vice President's authorization, see ibid.; DOD transcript,Air Threat Conference Call, Sept. 11, 2001. For Hadley's statement, see DOD transcript, Air Threat Conference Call, Sept. 11, 2001.

224.  For the quotation, see White House transcript, Libby interview with Newsweek, Nov. 2001. On the air-craft's identity, see White House record,White House Military Office Log, Sept. 11, 2001.

225.  On the NMCC, see DOD transcript,Air Threat Conference Call, Sept. 11, 2001. On the Secret Service's contacts with the FAA, see notes 208, 217. On the Secret Service conveying information to the White House, see DOD transcript, Air Threat Conference Call, Sept. 11, 2001; Nelson Garabito interview (Mar. 11, 2004).

226.  DOD transcript, Air Threat Conference Call, Sept. 11, 2001.

227.  Ibid.

228.  Ralph Eberhart interview (Mar. 1, 2004). On the morning of 9/11, General Eberhart was in his office at headquarters-roughly 30 minutes away from Cheyenne Mountain, where the operations center is located.

229.  DOD record, Continental Region chat log, Sept. 11, 2001.

230.  NEADS audio file, Mission Crew Commander position, channel 2, 10:32:12. For the text of the chat log message, see DOD record, Continental Region chat log, Sept. 11, 2001.

231.  For the statements of NEADS personnel, see Robert Marr interview (Jan. 23, 2004) (NEADS commander); Kevin Nasypany interview (Jan. 22, 2004) (mission commander); James Fox interview (Oct. 29, 2004) (senior weapons director). On the understanding of leaders in Washington, see DOD transcript, Air Threat Conference Call, Sept. 11, 2001. For the orders to Langley pilots, see NEADS audio file,Weapons Director position, recorder 1, channel 2, 10:10-11.

232.  For evidence of the President speaking to Rumsfeld, see White House notes,Ari Fleischer notes, Sept. 11, 2001. On inability to recall this conversation, see Donald Rumsfeld interview (Jan. 30, 2004).

233.  DOD note, transcript of Air Threat Conference Call, Sept. 11, 2001.

234.  Donald Rumsfeld interview (Jan. 30, 2004).At 11:15, Secretary Rumsfeld spoke to the President and told him DOD was working on refining the rules of engagement so pilots would have a better understanding of the circumstances under which an aircraft could be shot down. See, e.g., DOD notes, Stephen Cambone notes, Sept. 11, 2001. DOD did not circulate written rules of engagement until sometime after 1:00 P.M. See DOD memo, rules of engagement, Sept. 11, 2001 (faxed to Andrews Air Force Base at 1:45 P.M.).

235.  David Wherley interview (Feb. 27, 2004).

236. The 113th Wing first learned from the FAA tower at Andrews that the Secret Service wanted fighters air-borne.The FAA tower had been contacted by personnel at FAA headquarters, who were on an open line with senior agents from the President's detail. See Nelson Garabito interview (Mar. 11, 2004); Terry Van Steenbergen interview (Mar. 30, 2004). On the Secret Service agent relaying instructions, see USSS memo, Beauchamp to AD-Inspection, September 11 experience, Feb. 23, 2004. On the order to fly weapons free, see David Wherley interview (Feb. 27, 2004); DOD memo, interview of David Wherley, Oct. 3, 2001, p. 12.

237.  President Bush and Vice President Cheney meeting (Apr. 29, 2004).

238.  These estimates are based on analysis of Boeing 757 maximum operating speed data, FAA and military radar data, and assumptions regarding how the airplane would be operated en route to the Washington, D.C., area. The shortest time frame assumes maximum speed without regard to overspeed warnings, a straight-line path, and no time allowed for maneuvering or slowing to aim and crash the airplane into its target.The probable time frame allows for speeds consistent with the observed operation of the airplane prior to its final maneuvers and crash, as well as for maneuvers and slowing in the D.C. area to take aim.According to radar data, the fighters from Langley Air Force Base arrived over Washington at about 10:00 A.M. Two of the three Langley fighters were fully armed (i.e., with missiles and guns); the third fighter carried only guns. Craig Borgstrom interview (Dec. 1, 2003).

239.  For the pilots' awareness, see Dean Eckmann interview (Dec. 1, 2003); Bradley Derrig interview (Dec. 1, 2003); Craig Borgstrom interview (Dec. 1, 2003). For the quotation, see Dean Eckmann interview (Dec. 1, 2003). 240. For no authority at 10:10, see NEADS audio file, Mission Crew Commander, channel 2. For shootdown authority at 10:31, see DOD record, Continental Region chat log, Sept. 11, 2001. For possibility of ordering a shoot-down, see Larry Arnold interview (Feb. 2, 2004).

241.  NEADS audio file, Identification Technician position, recorder 1, channel 4, 10:02:22.