Personnel in NORAD’s operations center in Cheyenne Mountain, Colorado, take part in a major Cold War-style training exercise called Vigilant Guardian, a war game in which the theoretical enemy is Russia. [9/11 Commission, 3/1/2004 
; Denver Post, 8/28/2011; Colorado Springs Gazette, 9/10/2011] All of NORAD, including its subordinate units (see (6:30 a.m.) September 11, 2001), participates in the exercise. [Northeast Air Defense Sector, 8/23/2001; Canadian Broadcasting Corporation, 9/8/2011] More than 50 people in the NORAD Battle Management Center in Cheyenne Mountain take part. [Airman, 3/2002; Defense Video and Imagery Distribution System, 9/8/2011] Vigilant Guardian is an annual exercise and is scheduled to last two weeks. [Arkin, 2005, pp. 545; Canadian Broadcasting Corporation, 9/8/2011] It has been underway for several days. Those in the Cheyenne Mountain Operations Center (CMOC) have been participating in it “for at least three or four days,” according to Lieutenant Colonel Steven Armstrong, NORAD’s chief of plans and forces. [North American Aerospace Defense Command, 9/9/2011]
Vigilant Guardian Is a ‘Full-Blown Nuclear War’ Exercise – Vigilant Guardian is a “transition to wartime operations command post exercise,” according to an information page for its participants. [Northeast Air Defense Sector, 8/23/2001] The 1st Air Force’s book about 9/11 will describe it as a “simulated air war.” [Filson, 2003, pp. 55] Lieutenant Colonel William Glover, the commander of NORAD’s Air Warning Center, will later recall that it involves NORAD “simulating war.… You know, attacks coming from the outside, Soviet-style bombers coming in, cruise-missile attacks, that type of thing.” [Canadian Broadcasting Corporation, 9/8/2011] Ken Merchant, NORAD’s joint exercise design manager, will tell the 9/11 Commission that Vigilant Guardian is a “full-blown nuclear war” exercise, and includes bomber response and intercontinental ballistic missile response. [9/11 Commission, 3/4/2004]
Russia Is Imagined Enemy – The theoretical enemy in the exercise is Russia. [Denver Post, 8/28/2011] According to the 9/11 Commission Report, the exercise “postulated a bomber attack from the former Soviet Union.” [9/11 Commission, 7/24/2004, pp. 458] Merchant will explain that “NORAD must use Russia in its exercises at the strategic level since no other country poses a great enough threat to NORAD’s capabilities and responsibilities.” [9/11 Commission, 3/4/2004]
Personnel Updated on Exercise during Shift Change – Armstrong will later recall that today starts off “like any other day. We came in thinking it would be a normal day… we did a standard shift changeover in the morning and we were getting right into where we were at in relation to the exercise.” He will describe that in a shift change during the exercise, “We’d say, ‘Okay, here’s what happened during the night shift (or the day shift),’ and we’d give each other an update, and then we’d start planning for whatever was on the agenda for that day.” [North American Aerospace Defense Command, 9/9/2011] According to the Denver Post, after commencing his shift, Armstrong “mapped out strategy in a chess game of ever-escalating scenarios, from strained diplomacy to the outbreak of conventional warfare that headed inexorably toward nuclear conflict” with Russia. [Denver Post, 8/28/2011]
B-1 Bomber Scheduled to Fly out over Pacific Ocean – The “planned big event for the day” in the exercise is “supposed to be a B-1 bomber that was flying out of Fairchild Air Force Base [in Washington State] and going out over the Pacific,” according to Jeff Ford, an Air Force lieutenant colonel who is working in the CMOC. Ford will add that there are “other things going on as part of the exercise, air exercise events, and then some scripted inputs that we were reacting to there in the Air Warning Center, whether it be unknown aircraft that we scramble aircraft for to intercept—or whatever.” [Defense Video and Imagery Distribution System, 9/8/2011]
Exercise Posture Allegedly Helps Response to Attacks – Vigilant Guardian will reportedly end after 9:03 a.m., when the second plane hits the World Trade Center (see (Shortly After 9:03 a.m.) September 11, 2001), and the CMOC personnel participating in it will then become involved in responding to the real-world attacks. [Airman, 3/2002; Toronto Star, 11/11/2008] Glover will claim that the CMOC’s response to the terrorist attacks benefits from the position the operations center is in for the exercise. He will say NORAD is “lucky” because “all the directorates such as operations, logistics, security, all those folks were up in the [Cheyenne] Mountain on an exercise posture.” He will add that “these are the same folks that we would bring up in case of contingencies or in time of going to war. So, in reality, I had all the guys up into the NORAD Battle Management Center that I needed to conduct the exercise as well as the contingency operations that happened on 9/11.” [Defense Video and Imagery Distribution System, 9/8/2011]
NORAD Monitoring Russian Exercise – NORAD was created in 1958, during the Cold War, to protect North American airspace against nuclear attacks from the Soviet Union. [New York Times, 4/25/2004; Canadian Broadcasting Corporation, 8/6/2004; Legion Magazine, 11/2004] According to the Toronto Star, “Whether it’s a simulation or a real-world event, the role of the [CMOC] is to fuse every critical piece of information NORAD has into a concise and crystalline snapshot.” [Toronto Star, 12/9/2001] As well as the Vigilant Guardian exercise, NORAD is currently in the middle of an operation called Northern Vigilance, with its fighter jets deployed to Alaska and Northern Canada to monitor an exercise being run by the Russian Air Force (see September 9, 2001). [North American Aerospace Defense Command, 9/9/2001] The battle staff members in Cheyenne Mountain are positioned to deal with both this operation and the exercise. [9/11 Commission, 3/1/2004 ]
8:48 a.m. September 11, 2001: NORAD Operations Center Personnel See Television Coverage of First Crash, but Unaware of Details
Personnel in the NORAD operations center in Cheyenne Mountain, Colorado, learn of the first plane hitting the World Trade Center from television coverage of the attack, but do not realize the crash involved the hijacked aircraft they have just been notified of. [Calgary Herald, 10/1/2001; Ottawa Citizen, 9/11/2002; Defense Video and Imagery Distribution System, 9/8/2011] Jeff Ford, an Air Force lieutenant colonel working in the Cheyenne Mountain Operations Center (CMOC), will later recall, “[W]e started seeing the TV inputs from CNN on the aircraft, the first aircraft that had hit the Twin Towers.” [Defense Video and Imagery Distribution System, 9/8/2011] Major General Rick Findley, NORAD’s director of operations, has just learned that the FAA has requested NORAD assistance with a hijacking (see (8.46 a.m.) September 11, 2001). [9/11 Commission, 3/1/2004 ; Spencer, 2008, pp. 38-39] He now enters the battle cab at the operations center. Someone there tells him, “Sir, you might want to look at that.” Findley will later recall: “I looked up and there was the CNN image of the World Trade Center. There was a hole in the side of one of the buildings.”
CMOC Personnel Think Small Plane Hit WTC – Findley asks, “What’s that from?” and is told, “Well, they’re saying it’s a commuter aircraft.” Findley says, “That’s too big a hole for a commuter aircraft.” He asks if the crash was caused by the hijacked aircraft he has been informed of. “I was scratching my head, wondering if it was another aircraft altogether,” he will recall. [Calgary Herald, 10/1/2001; Canadian Broadcasting Corporation, 9/11/2002] Others in the CMOC are unaware that the crash was the result of a terrorist attack and involved a large commercial aircraft. Lieutenant Colonel Steven Armstrong, NORAD’s chief of plans and forces, will recall, “[W]e didn’t really know that it was anything other than perhaps a general aviation aircraft because those were the first indications that we had was it was just… reported like a small, maybe a general aviation aircraft that had hit one of the buildings.” [North American Aerospace Defense Command, 9/9/2011] According to Lieutenant Colonel William Glover, the commander of NORAD’s Air Warning Center: “[W]e weren’t sure whether it was a mistake… was this intentional? Was there a problem? The weather was good, you know, that type of thing. So we really didn’t know what the reason was that this aircraft struck the tower.” [Canadian Broadcasting Corporation, 9/8/2011] Ford will recall: “[W]e knew something was wrong because there really wasn’t any reason for any navigational problems for that aircraft. There might have been a malfunction or something on the aircraft that had taken place, but we really didn’t have any indications of what was going on yet.” [Defense Video and Imagery Distribution System, 9/8/2011]
CMOC Personnel Unaware that Crash Was Deliberate – The CMOC is “the nerve centre of North America’s air defense,” according to the BBC. [BBC, 9/1/2002] Its role, according to the Toronto Star, is “to fuse every critical piece of information NORAD has into a concise and crystalline snapshot.” [Toronto Star, 12/9/2001] But it is only after personnel there see the television coverage of the second plane hitting the WTC at 9:03 a.m. that they realize “we had something much more sinister than just an accident, a really coordinated and deliberate action,” according to Findley. [Ottawa Citizen, 9/11/2002] Armstrong will recall: “[W]hen we saw the video [of the second crash], we said: ‘Wait a second. Those are commercial-size airplanes. Those aren’t general aviation aircraft.’ That obviously changed the situation significantly.” [North American Aerospace Defense Command, 9/9/2011] According to Glover, after the second crash, “We knew then that the first one was not a mistake and we knew that this was intentional.” [Canadian Broadcasting Corporation, 9/8/2011]
After 9:03 a.m. September 11, 2001: NORAD Operations Center in ‘Information Void,’ Learning of Crisis from Television
Personnel in the NORAD operations center in Cheyenne Mountain, Colorado, are in what one officer there will call an “information void,” and are learning about ongoing events mostly from television reports. [Denver Post, 8/28/2011; North American Aerospace Defense Command, 9/9/2011] Major General Rick Findley, NORAD’s director of operations, will tell the 9/11 Commission that those in the Cheyenne Mountain Operations Center (CMOC) gain their “first awareness of a second impact at the World Trade Center… from the media simulcast of the event.” Findley only then realizes there is an “ongoing coordinated attack” taking place. But, he will tell the 9/11 Commission, he “did not know the exact facts of what caused both explosions.” [9/11 Commission, 3/1/2004 ] According to Lieutenant Colonel Steven Armstrong, NORAD’s chief of plans and forces, after the second crash, “[W]e were just kind of watching it unfold on CNN, and then we started making the phone calls and we tried to start building a bigger picture.” [North American Aerospace Defense Command, 9/9/2011] Armstrong will later recall, “We’re reaching out to everybody and their brother, trying to get as much information as we can to figure out what’s going on with the national airspace.” However, he will say, “[T]he majority of the information we’re getting at the time is literally off the TV.” [Denver Post, 8/28/2011] The CMOC reaches out to NORAD’s regional air defense sectors to try and get information. But, according to Armstrong, “they were pretty busy trying to run fighters and do intercepts and figure out where the bad guys were.” Therefore, Armstrong will say, “we were out there in an information void, just looking for anything that we could find.” [North American Aerospace Defense Command, 9/9/2011] Lieutenant Colonel William Glover, the commander of NORAD’s Air Warning Center, will recall that this morning is his “first time, you know, thinking about the fog of war, because we didn’t know what was going on.” [Canadian Broadcasting Corporation, 9/8/2011] Findley will reflect, “I wouldn’t call it flat-footed, but we were a little bit behind the power curve most of that morning as we were trying to figure out exactly what transpired.” [Canadian Press, 9/10/2006]
10:15 a.m. September 11, 2001: NORAD Operations Center in Colorado Closes Its Blast Doors
The massive doors leading to NORAD’s operations center in Cheyenne Mountain, Colorado, designed to protect the center from a nuclear blast, are closed for the first time ever in a real-world, non-exercise event, though the reason for this is unclear. [Toronto Star, 12/9/2001; Aviation Week and Space Technology, 6/3/2002; BBC, 9/1/2002; North American Aerospace Defense Command, 9/9/2011] The two steel blast doors, one third of a mile inside the mountain, guard the heart of NORAD’s Cheyenne Mountain Operations Center (CMOC) and are intended to seal the complex to protect it from a nuclear strike. The doors are three feet thick, more than 10 feet high, and each weigh 25 tons. During an attack, they can swing shut in 30 to 40 seconds. [Airman, 1/1996; Nation, 5/5/2008; Colorado Springs Gazette, 5/10/2008]
Doors Are Shut for the First Time, except for Exercises – Air Force officer William Astore will later recall that when he worked inside Cheyenne Mountain between 1985 and 1988, the blast doors were kept open, “except, of course, during ‘exercises,’ when the mountain ‘buttoned up’ its self-contained world.” [Nation, 5/5/2008] Now is the first time since the CMOC opened in 1966 that the blast doors have been shut because of a real-world, non-exercise event. Lieutenant Colonel Steven Armstrong, NORAD’s chief of plans and forces, who is in the CMOC on this day, will later comment, “The fact that we closed the blast doors… was a significant event.” [Toronto Star, 12/9/2001; Colorado Springs Gazette, 6/14/2004; North American Aerospace Defense Command, 9/9/2011]
Accounts Conflict over Why the Doors Are Closed – The reason the blast doors are shut is unclear. According to the Toronto Star, they are closed because “no one yet knew who was behind the attack—or what else might be en route.” [Toronto Star, 12/9/2001] But Aviation Week and Space Technology magazine will report that “NORAD commanders ordered [the] massive steel doors be closed” after “someone—possibly President Bush—ordered the military to a Force Protection Condition Delta wartime posture” (see (Between 10:10 a.m. and 10:35 a.m.) September 11, 2001). [Aviation Week and Space Technology, 6/3/2002] Other reports will say the doors are shut due to a report the CMOC received about an aircraft that is incorrectly suspected of being hijacked and targeting Cheyenne Mountain (see (10:10 a.m.) September 11, 2001). [BBC, 9/1/2002; Grant, 2004, pp. 26; Colorado Springs Gazette, 6/14/2004; Washington Post, 7/29/2006] A NORAD representative on the Pentagon’s air threat conference call will report over the conference call that the blast doors are in fact shut in response to information received at the CMOC about a number of suspicious trucks that are supposedly heading toward the CMOC (see (Shortly After 1:05 p.m.) September 11, 2001). [US Department of Defense, 9/11/2001 ]
Doors Are Re-Opened Four Hours Later – The blast doors will be re-opened four hours after they are shut, “when officials learned the threat was bogus,” according to the Colorado Springs Gazette. [Colorado Springs Gazette, 6/14/2004]
