Context of '8:46 a.m.-9:37 a.m. September 11, 2001: Aviation Unit Based near Pentagon away for Weapons Training at Time of Attacks'

A helicopter and its crew that are always on standby for “contingency” missions in the Washington area are away from base early this morning conducting a traffic survey, but apparently return at some point before the Pentagon is hit. The crew belongs to the 12th Aviation Battalion. [US Army Center for Military History, 11/14/2001 ; Army Center of Military History, 11/14/2001 ] The 12th Aviation Battalion is stationed at Davison Army Airfield at Fort Belvoir, located 12 miles south of the Pentagon. It is the aviation support unit for the Military District of Washington, and operates UH-1 “Huey” and UH-60 Black Hawk helicopters. [Military District of Washington, 8/2000] According to a chief warrant officer with the unit, the 12th Aviation Battalion has “two crews that are always on standby for any kind of contingency mission.” It is one of these crews that is “out flying around doing a traffic survey.” [Army Center of Military History, 11/14/2001 ] The exact time period during which the crew and their helicopter are away from base is unstated, but they apparently return to Davison Airfield before 9:37 a.m., when the Pentagon is hit (see Shortly Before 9:37 a.m. September 11, 2001). [US Army Center for Military History, 11/14/2001 ] They will be the first crew with the battalion to take off in support of the rescue operations at the Pentagon once the unit’s aircraft are permitted to launch again following the attack. Others members of the 12th Aviation Battalion are also away from base this morning, for weapons training (see 8:46 a.m.-9:37 a.m. September 11, 2001). [Army Center of Military History, 11/14/2001 ]

Fort AP Hill. [Source: United States Army]At the time of the attacks on the World Trade Center, members of the Army’s aviation support unit for the Washington, DC, area are away for weapons training, and do not set out to return to their base until after the time the Pentagon is hit. [Army Center of Military History, 11/14/2001 ; Pentagram, 11/16/2001; Fort Belvoir News, 1/18/2002] The 12th Aviation Battalion is the Military District of Washington’s aviation support unit, and includes three helicopter companies. It operates UH-1 “Huey” and UH-60 Black Hawk helicopters. The battalion is stationed at Davison Army Airfield, which is at Fort Belvoir, 12 miles south of the Pentagon. [Military District of Washington, 8/2000] Davison Airfield’s missions include maintaining “a readiness posture in support of contingency plans,” exercising “operational control” of the Washington area airspace, and providing “aviation support for the White House, US government officials, Department of Defense, Department of the Army, and other government agencies.” [Pentagram, 5/7/1999] A chief warrant officer with the 12th Aviation Battalion will later recall that members of the battalion are away this morning, at the shooting range at another Virginia Army base, Fort AP Hill, for their annual weapons training. They had set off early and driven there—a journey of one and a half to two hours. They are at the range when the attacks on the WTC take place, and only learn of them when the sister of one of their captains calls her brother with news of the attacks, presumably after seeing the coverage on television. The chief warrant officer will recall that, after hearing of the second attack on the WTC, “[W]e were all pretty much thinking we probably need to go—you know, probably need to come to work.” The range officer calls Davison Airfield and is told that the members of the battalion should “pack it in and come on back” to base. He is also told during the call that an aircraft has crashed into the Pentagon (see 9:37 a.m. September 11, 2001), meaning this call does not occur until after 9:37 a.m. According to the chief warrant officer, the Pentagon “is basically one of our missions. So we just pretty much packed up and came back up here and came into work.” Exactly how many of the 12th Aviation Battalion’s members are away from base for the weapons training is unstated, as is the exact time they arrive back at Davison Airfield. But considering it is one and a half to two hours drive between there and the range, they presumably do not get there until some time after about 11:15 a.m. When they do eventually get back to base, the battalion members will prepare to launch helicopters in response to the Pentagon attack (see (After 11:15 a.m.) September 11, 2001). [Army Center of Military History, 11/14/2001 ; Fort Belvoir News, 1/18/2002]

In the Defense Intelligence Agency (DIA) comptroller’s office, on the first floor of the Pentagon’s C-ring, workers are reportedly uneasy at the news of the plane crashes in New York. However, Paul Gonzales, a retired Navy commander who is now a supervisor there, confidently declares that the Pentagon is probably the safest building in the world. So by 9:30 a.m., most of the workers in his section will be settling back to their usual business. The DIA comptroller’s office is one of the areas impacted when the Pentagon is hit at 9:37 (see 9:37 a.m. September 11, 2001). Of the 18 workers there, seven will die and five others will be hospitalized. [Washington Post, 3/11/2002; Vogel, 2007, pp. 429; Tennessean, 9/11/2007]

At the National Security Agency (NSA) headquarters in Fort Meade, Maryland, Michael Hayden, the agency’s director, orders the evacuation of all nonessential personnel from the NSA complex. His two reasons for this, he later says, are “just pure safety,” and to protect the people who work at the agency by sending “them home on the dispersal plan.” In a 2007 speech, he will state that he gave this order at 9:30 a.m. But in the account of author James Bamford, around the time Hayden gives the order he hears “some early reports about the explosion at the Pentagon.” Yet the attack on the Pentagon does not occur until 9:37 (see 9:37 a.m. September 11, 2001). The reason for this discrepancy is unclear. Hayden’s evacuation order is announced over loudspeakers throughout the NSA, and many of the 16,000 employees there leave. After hearing for sure that the Pentagon has been struck and that one or more hijacked aircraft is heading toward Washington, Hayden orders the three to four thousand remaining essential personnel to immediately evacuate the agency’s three tall towers and relocate to the low-rise Ops 1 Building. However, as Hayden later says, “[W]e really couldn’t afford to move the counterterrorism shop” where experts and linguists who track terrorists’ foreign communications work, even though it is located near the top of one of the NSA’s high-rise buildings. Maureen Baginski, the NSA’s director of signals intelligence, goes up there shortly after the time of the Pentagon attack to calm down the workers who, according to Hayden, are “emotionally shattered.” [US Congress, 10/17/2002; Bamford, 2004, pp. 52-54; National Journal, 6/19/2006; Central Intelligence Agency, 5/4/2007] At 9:53, analysts in the counterterrorism office will pick up and quickly translate a phone call from a bin Laden operative in Afghanistan, apparently referring to the attacks (see 9:53 a.m. September 11, 2001).

Two unidentified military aircraft fly in the vicinity of the Pentagon at an altitude of over 20,000 feet, and are in the area during the minutes before the Pentagon is hit. [Federal Aviation Administration, 9/20/2001 ; 9/11 Commission, 7/28/2003 ] Between at least 9:31 a.m. and 9:40 a.m., the two aircraft communicate with the air traffic control tower at Washington’s Reagan National Airport, which is less than a mile from the Pentagon. [Federal Aviation Administration, 9/20/2001 ; St. Petersburg Times, 10/3/2001] Radar data will show that they fly “in trail” (in single file, with one aircraft directly behind the other) at 21,000 feet, and are overhead during the last few minutes that Flight 77 is airborne, before it hits the Pentagon at 9:37 a.m. (see 9:37 a.m. September 11, 2001). [9/11 Commission, 7/28/2003 ]
Launched from Delaware Base - The identities of the two aircraft are unclear. They have the call signs “Bobcat 14” and “Bobcat 17.” [Federal Aviation Administration, 9/20/2001 ] A 9/11 Commission memorandum will state that “flight strips and other information indicate that Bobcat 14 and Bobcat 17 originated out of Dover Air Force Base in Delaware.… It is possible, but not confirmed, that they were Air Force corporate passenger jets.”
Airport Managers Do Not Recall Planes - Two key officials will later be unable to specifically recall the aircraft when questioned by the 9/11 Commission. Bob Lazar, the acting operations manager at Reagan National Airport, will say he “did not remember any aircraft with the call sign ‘Bobcat’ that hung out over the National airspace” on this day. However, as well as two of the fighter jets that are inbound from Langley Air Force Base (see (9:25 a.m.-9:30 a.m.) September 11, 2001), he will recall two aircraft “coming from the north, but he did not think that they entered National’s airspace.” Donny Simons, the airport manager at Baltimore-Washington International Airport in Linthicum, Maryland, will stress “that he did not remember the Bobcats specifically,” but he speculates that controllers at his airport “were working the two ‘Bobcats’ and needed vectors from National controllers.” [9/11 Commission, 7/28/2003 ]

A group from FAA headquarters, who are apparently oblivious to the morning’s crisis, request and are given a tour of the air traffic control tower at Washington’s Reagan National Airport, until they are forced to leave there just before the time of the Pentagon attack. [Spencer, 2008, pp. 157-158] Reagan Airport is located less than a mile from the Pentagon. [St. Petersburg Times, 10/3/2001]
Tour Group Wants to See Tower - At 9:32, the tower supervisor, Chris Stephenson, receives a phone call from one of the airport’s maintenance workers. The maintenance worker says he has a group there from the FAA’s Washington headquarters that is visiting the airport to go over some maintenance issues, but they are also curious to see what goes on in the control tower. It appears the FAA personnel are unaware of the attacks in New York, and Stephenson is asked if it is okay to bring them up. Though he is busy dealing with the chaos resulting from the ground stop recently ordered by the FAA’s Command Center (see (9:26 a.m.) September 11, 2001), Stephenson reluctantly agrees. The group arrives moments later, but Stephenson tries to ignore them. According to author Lynn Spencer, Stephenson is as yet unaware that an errant aircraft has been spotted heading toward Washington (see (9:33 a.m.) September 11, 2001). [Spencer, 2008, pp. 157] But according to USA Today, the Secret Service warned him about this aircraft at around 9:30 a.m. (see (9:30 a.m.) September 11, 2001). [USA Today, 8/11/2002]
Group Ordered to Leave - Shortly after the group arrives, Stephenson is called by a controller at the TRACON and notified of the unidentified aircraft (presumably Flight 77), which is five miles west of the tower (see (9:36 a.m.) September 11, 2001). When he looks out the window, he sees it, now less than a mile away and approaching fast. Stephenson yells at the tour group: “Out! Get out!” The FAA group heads off down the stairs, but the last in the line looks out the window at the descending aircraft and asks, “What’s that guy doing?” ”Get out!” Stephenson repeats, and pushes the man into the stairwell. Soon afterwards, the Pentagon is hit (see 9:37 a.m. September 11, 2001). [Spencer, 2008, pp. 158]

The air traffic control tower at an Army airfield near the Pentagon receives a call from someone at Washington’s Reagan National Airport—presumably an air traffic controller—who instructs it to recall all its aircraft. [US Army Center for Military History, 11/14/2001 ] Davison Army Airfield is at Fort Belvoir, 12 miles south of the Pentagon. The 12th Aviation Battalion, which is the Military District of Washington’s aviation support unit, is stationed there. This includes three helicopter companies that fly UH-1 “Huey” and UH-60 Black Hawk helicopters. [Military District of Washington, 8/2000]
Airfield Told to Land All Aircraft 'Very Quickly' - According to a supervisor of air traffic control at Davison Airfield who is currently in the airfield’s control tower, shortly before the time when the Pentagon is hit a controller at his facility receives the call from Reagan Airport telling them to recall all their air traffic. The supervisor, who will say that the caller is “going crazy,” takes over the call. The caller then tells him to “recall all your traffic. Just make sure that everybody lands.… [H]e was like, telling us, everybody that you got outside, bring them in and land them quickly, very quickly.” The supervisor tells him, “Give me a reason and I’ll do it,” but the caller responds, “I can’t tell you the reason, but you need to do this.” [US Army Center for Military History, 11/14/2001 ] (At around 9:32 a.m., according to the 9/11 Commission, Washington’s Dulles Airport notified Reagan Airport of a “radar target tracking eastbound at a high rate of speed” toward Washington (see 9:32 a.m. September 11, 2001), so it is plausible that this is what has prompted Reagan Airport to call the Davison control tower. [9/11 Commission, 8/26/2004, pp. 33 ] )
Davison Airfield Recalls Its Aircraft - After the caller hangs up, the supervisor at Davison Airfield instructs the air traffic controller at his facility to “tell everybody to come in.” The controller then starts “recalling everybody that just departed,” and the supervisor approves “for them to make it straight in, the helicopters to land straight in without using the regular traffic pattern.” The control tower recalls its aircraft individually, rather than putting out a single broadcast telling all aircraft to return to the airfield. The supervisor will recall: “[E]verybody was coming in. And at that time when everybody was coming in… I was like thinking, why? Why do they want to recall everybody? That means that something is going on.” While the control tower is still recalling its aircraft, the supervisor looks out of a window to the northeast, and notices a large black cloud of smoke in the area of the Pentagon, the result of the attack there. [US Army Center for Military History, 11/14/2001 ] It is unclear what aircraft from Davison Airfield are airborne and recalled to base. But a 12th Aviation Battalion helicopter and its crew that are always on standby for “contingency” missions have been away this morning, conducting a traffic survey (see Early Morning September 11, 2001). They are presumably recalled at this time, if not beforehand. [Army Center of Military History, 11/14/2001 ]

The Pentagon explodes. [Source: Donley/ Sipa]Flight 77 crashes into the Pentagon. All 64 people on the plane are killed. A hundred-and-twenty-four people working in the building are killed, and a further victim will die in hospital several days later. Hijackers Hani Hanjour, Khalid Almihdhar, Majed Moqed, Nawaf Alhazmi, and Salem Alhazmi presumably are killed instantly. (Typically, they are not included in the death counts.) [CNN, 9/17/2001; North American Aerospace Defense Command, 9/18/2001; Guardian, 10/17/2001; Washington Post, 11/21/2001; USA Today, 8/13/2002; Associated Press, 8/21/2002; MSNBC, 9/3/2002; ABC News, 9/11/2002; CBS News, 9/11/2002] Flight 77 hits the first floor of the Pentagon’s west wall. The impact and the resulting explosion heavily damage the building’s three outer rings. The path of destruction cuts through Army accounting offices on the outer E Ring, the Navy Command Center on the D Ring, and the Defense Intelligence Agency’s comptroller’s office on the C Ring. [Vogel, 2007, pp. 431 and 449] Flight 77 strikes the only side of the Pentagon that had recently been renovated—it was “within days of being totally [renovated].” [US Department of Defense, 9/15/2001] “It was the only area of the Pentagon with a sprinkler system, and it had been reconstructed with a web of steel columns and bars to withstand bomb blasts. The area struck by the plane also had blast-resistant windows—two inches thick and 2,500 pounds each—that stayed intact during the crash and fire. While perhaps, 4,500 people normally would have been working in the hardest-hit areas, because of the renovation work only about 800 were there.” More than 25,000 people work at the Pentagon. [Los Angeles Times, 9/16/2001] Furthermore, the plane hits an area that has no basement. As journalist Steve Vogel later points out, “If there had been one under the first floor, its occupants could easily have been trapped by fire and killed when the upper floors collapsed.” [Vogel, 2007, pp. 450]

A number of FBI agents are, for unknown reasons, already at the Navy Annex—a building near the Pentagon—when the Pentagon is hit, and help clear the Navy Annex when it is evacuated in response to the attack. [Naval Historical Center, 12/21/2001] The Navy Annex is a massive building located a few hundred yards uphill from the Pentagon. It has enough room for 6,000 employees. Currently, about 100 Navy personnel work in it, and most of the space is used by the Marine Corps. [American Forces Press Service, 9/24/2001; Goldberg et al., 2007, pp. 14; GlobalSecurity (.org), 5/7/2011]
Building Manager Sounds Fire Alarm, Starts Evacuation - Coneleous Alexander, a building manager at the Navy Annex, hears the explosion from the Pentagon attack (see 9:37 a.m. September 11, 2001). Alexander “knew immediately it was the Pentagon” that had been hit, he will later recall. He runs to the front of the Navy Annex and sees the smoke coming from the Pentagon. Alexander immediately sounds the fire alarm and starts getting people out of the Navy Annex. He receives no directions from the Defense Protective Service (DPS)—the law enforcement agency that guards the Pentagon—on what to do, but knows from his training that he has to get people out of the building.
FBI Agents Already at Navy Annex, Assist Evacuation - As the evacuation begins, Alexander notices about 10 FBI agents going down the halls of the Navy Annex. He knows what they are because they have “FBI” written on the backs of their jackets. However, he does not know where they have come from. Interviewed three months later, Alexander will speculate that the FBI agents may have come to the Navy Annex because they received prior notification of a hijacked aircraft heading toward Washington, DC, but he will say their presence at his building “puzzles him to this day.” Because there are no members of the DPS on hand to help evacuate the building, the FBI agents assist in this task. The agents will also give Alexander updates on alerts about potential further attacks. People are moved “farther and farther” from the building following each threat warning, according to Alexander. Later in the day, Navy and Marine Corps senior officers will re-enter the Navy Annex to establish a command center there (see (3:00 p.m.) September 11, 2001). [Historical Office, Office of the Secretary of Defense, 11/5/2001; Naval Historical Center, 12/21/2001]

Marc Sasseville. [Source: CBC]Four pilots with the District of Columbia Air National Guard (DCANG) at Andrews Air Force Base, near Washington, finally receive authorization to get airborne in their fighter jets, and are given instructions on their mission. The pilots are Lieutenant Colonel Marc Sasseville, Lieutenant Heather Penney Garcia, Captain Brandon Rasmussen, and Major Daniel Caine.
Pilot Waiting 'for Somebody to Task Me with Something' - Rasmussen will later recall that, although he and his colleagues at the unit had been aware of the attacks in New York, it is only after the Pentagon is hit (see 9:37 a.m. September 11, 2001) that “we knew that we were going to be sticking around home and being quite busy.” And until the pilots are authorized to take off, he is “just kind of standing back, waiting for somebody to task me with something.” He will recall, “I was just waiting at the ops desk for someone to say, ‘Okay, we’ve been cleared to take off and go.’”
Sasseville Briefs Other Pilots - Rasmussen says that, after Sasseville and Caine receive authorization from their wing commander to get airborne and to use missiles, Sasseville, who is the acting operations group commander, looks at Penney Garcia and says, “You’re flying with me, and [Caine] you’re flying with [Rasmussen], do suit up and get out there as quick as possible.” According to another account, Sasseville gives his three fellow pilots a short briefing, telling them: “I have no idea what’s going on, but we’re flying. Here’s our frequency. We’ll split up the area as we have to. Just defend as required. We’ll talk about the rest in the air.” [Aviation Week and Space Technology, 9/9/2002; Filson, 2003, pp. 82-84; Rasmussen, 9/18/2003] Sasseville will recall, “There wasn’t a whole hell of a lot to talk about, because we didn’t know what was going on.” [Vogel, 2007, pp. 446]
Pilots Prepare to Fly - According to Rasmussen: “We were relieved to actually be given permission to go up and do something instead of feeling totally helpless. I mean we are fighter pilots, just like guard dogs chomping at the bit ready to go.” The four pilots run down the hallway and throw on their gear, grabbing their helmets, g-suits, and parachute harnesses, before heading to the operations desk to get their aircraft assignments. [Aviation Week and Space Technology, 9/9/2002; Rasmussen, 9/18/2003]
Commander Gives Instructions - According to author Leslie Filson, before Sasseville and Penney Garcia head to their jets, Brigadier General David Wherley, the commander of the DC Air National Guard, gives them instructions, regarding their mission. As Wherley will later recall, “My translation of the rules [of engagement] to [Sasseville] was, ‘You have weapons free flight-lead control.’” [Filson, 2003, pp. 82] “Weapons free” means the decision whether to shoot at a hostile aircraft rests with the lead pilot. [9/11 Commission, 7/24/2004, pp. 44] Wherley says, “Do you understand what I’m asking you to do?” and both pilots respond, “Yes.” Wherley then tells them to be careful. “It was important for them to understand that this was weapons free,” he will recall. [Filson, 2003, pp. 82] However, Sasseville will tell the 9/11 Commission that he does not remember receiving the rules of engagement he is supposed to follow until later on, after he has taken off. [9/11 Commission, 3/8/2004 ]
Jets Don't Launch until 10:42 and After - The exact times when the four pilots are authorized to get airborne and receive their mission instructions are unclear. But Sasseville and Penney Garcia will take off from Andrews at 10:42 a.m., with their planes armed only with guns, and no missiles (see 10:42 a.m. September 11, 2001). Rasmussen and Caine take off at 11:11 a.m., by which time their jets have been armed with missiles (see 11:11 a.m. September 11, 2001). [Filson, 2003, pp. 82-84; 9/11 Commission, 2004]

Twenty minutes after the 9/11 attacks in New York (see 8:46 a.m. September 11, 2001 and 9:03 a.m. September 11, 2001) and Washington (see 9:37 a.m. September 11, 2001), a bomb truck is stationed in downtown Oklahoma City, in preparation for any potential bombing related to the 1995 Oklahoma City bombing (see 8:35 a.m. - 9:02 a.m. April 19, 1995). Additionally, an Oklahoma County Sheriff’s Department command post is activated where convicted bombing conspirator Terry Nichols (see September 5, 2001) is being held. [The Oklahoman, 4/2009]

Brigadier General Montague Winfield finally returns to his post as the deputy director for operations (DDO) in the National Military Command Center (NMCC) at the Pentagon, after leaving a colleague, who only recently qualified to take over the position, to stand in for him throughout the terrorist attacks. [9/11 Commission, 4/29/2004 ; 9/11 Commission, 6/17/2004] At 8:30 a.m. Winfield left his post to attend a pre-scheduled meeting that was unrelated to the morning’s attacks and had been convened by the Air Force. Since that time, Captain Charles Leidig has replaced him as the DDO (see 8:30 a.m. September 11, 2001). Leidig, the deputy for Command Center operations, only qualified to stand in as the DDO in the NMCC about a month ago. Even though officers in the NMCC realized the US was under terrorist attack when the second plane hit the World Trade Center at 9:03 a.m., Winfield did not return to his post at that time (see (Shortly After 9:03 a.m.) September 11, 2001). [9/11 Commission, 7/21/2003 ; 9/11 Commission, 4/29/2004 ; 9/11 Commission, 6/17/2004 ]
Winfield Returns to His Post, but Timing Unclear - Now Winfield finally relieves Leidig and resumes his duties as DDO. This happens after Flight 93 has crashed in Pennsylvania (see (10:03 a.m.-10:10 a.m.) September 11, 2001 and (10:06 a.m.) September 11, 2001), although the exact time is unclear. In a private interview with the 9/11 Commission, Leidig will say he is “certain that Winfield returned [from the meeting] after the Pentagon was hit” at 9:37 a.m. (see 9:37 a.m. September 11, 2001), but he “is not certain of Winfield’s arrival in relationship with the vice chairman” of the Joint Chiefs of Staff, General Richard Myers. [9/11 Commission, 4/29/2004 ] (According to the 9/11 Commission Report, Myers arrived at the NMCC shortly before 10:00 a.m. (see (Between 9:55 a.m. and 10:25 a.m.) September 11, 2001). [9/11 Commission, 7/24/2004, pp. 38] ) Winfield then takes over as DDO “at some point in relation to the report of the Pennsylvania crash,” according to Leidig. As the 9/11 Commission will point out, since the crash of Flight 93 happened around 10:03 a.m., “any reporting would be after that time.” [9/11 Commission, 4/29/2004 ] During a public hearing of the 9/11 Commission, Leidig will similarly say that Winfield takes over from him “[r]ight after we resolved what was going on with United 93.” He will also say that a report over the NMCC’s air threat conference at 10:37 a.m., about an anonymous threat against Air Force One (see 10:32 a.m. September 11, 2001), occurs “right after I was relieved on the watch by General Winfield.” [9/11 Commission, 6/17/2004] This would indicate that Winfield takes over from Leidig at around 10:30 a.m.
Unclear If Winfield Returns to Post Immediately after Meeting - It is also unclear whether Winfield returns to his position as DDO immediately after leaving the Air Force-convened meeting, or he allowed Leidig to continue in his place even while he was available to resume his duties. A 9/11 Commission memorandum will state, “Winfield transitioned into the position [of DDO] upon his return to the NMCC,” following the meeting. [9/11 Commission, 7/21/2003 ] Leidig will recall that he “looked up at one point and General Winfield was standing next to him.” He will also recall that Myers “looked at him at one time and realized the coordinator [i.e. the DDO] was not a general as the position called for, and asked who the general or admiral was that had duty that day.” The guidance that was subsequently given was “to get General Winfield briefed up and in the chair.”
Leidig Listens to Conference before Returning to Post - After Winfield returns to his position as DDO, Leidig initially “stands next to him and listens to the [NMCC’s air threat] conference.” Leidig will then transition into his regular job, which involves making sure the NMCC operates properly, and start dealing with the smoke coming into the center and other issues effecting operations there. [9/11 Commission, 4/29/2004 ]

Helicopters belonging to the 12th Aviation Battalion. [Source: United States Army]Helicopter crews with an Army aviation unit based near the Pentagon are initially unable to launch after returning from weapons training, because, they are told, they are “locked down until further notice.” [Army Center of Military History, 11/14/2001 ] The 12th Aviation Battalion is stationed at Davison Army Airfield, which is at Fort Belvoir, 12 miles south of the Pentagon. It is the Military District of Washington’s aviation support unit, and includes three helicopter companies that fly UH-1 “Huey” and UH-60 Black Hawk helicopters. [Military District of Washington, 8/2000] But at the time of the attacks on the World Trade Center, an unspecified number of the battalion’s members were away at the shooting range at Fort AP Hill, for their annual weapons training (see 8:46 a.m.-9:37 a.m. September 11, 2001). They only set out on the one and a half to two hours drive back to base after the Pentagon was hit. One of the battalion’s helicopter pilots, who says the Pentagon is “basically one of our missions,” will later recall that after arriving back at Davison Airfield, his company commander “pretty much had us all get together, and he broke us down into aviation crews… and then he briefed us on what to expect.” The battalion’s helicopters are put “online,” meaning “we preflight our aircraft, got ready, and we went ahead and took everything out.” But, the pilot will say: “then basically we were locked down until further notice. That’s what we were told. And at that point, aviation got hit the hardest, so nobody was flying anywhere unless we had specific permission.… It was a waiting game.” The first helicopter to take off from Davison Airfield transports some engineers to the Pentagon, though the time it launches at is unstated. The 12th Aviation Battalion helicopters will subsequently be involved with supporting Operation Noble Eagle, the new homeland defense mission after 9/11. [Army Center of Military History, 11/14/2001 ]

American Airlines issues a statement confirming that it has lost two of its aircraft in “tragic incidents this morning.” The statement identifies the aircraft as “Flight 11, a Boeing 767 en route from Boston to Los Angeles,” and “Flight 77, a Boeing 757 operating from Washington Dulles to Los Angeles.” The statement adds, “Because of the heightened security due to the nature of today’s events, American said it is working closely with US government authorities and will not release more information at this time.” [Associated Press, 2001 ; Associated Press, 9/11/2001; CNN, 9/12/2001] Flight 11 hit the North Tower of the World Trade Center at 8:46 a.m. (see 8:46 a.m. September 11, 2001) and Flight 77 hit the Pentagon at 9:37 a.m. (see 9:37 a.m. September 11, 2001). [9/11 Commission, 6/17/2004]

James L. Jones. [Source: US Marine Corps]The Navy establishes a new command center at the Navy Annex in Arlington, Virginia, after its original command center was destroyed in the attack on the Pentagon. The original Navy Command Center, located on the first floor of the Pentagon, provided Navy leaders with timely information and intelligence about operations around the world. But it was destroyed, and many of its personnel died, when the Pentagon was hit (see 9:37 a.m. September 11, 2001 and 9:37 a.m. September 11, 2001). [Washington Post, 1/20/2002; Goldberg et al., 2007, pp. 133] Reportedly, 70 percent of the Navy’s spaces in the Pentagon were damaged or destroyed in the Pentagon attack. [Navy Times, 10/1/2001]
Navy Invited to Join Marines at Navy Annex - General James Jones, the commandant of the Marine Corps, therefore invited several of his Navy counterparts and their staffs to co-locate with the Marine Corps at the Navy Annex. [Sea Power, 1/2002] The Navy Annex is a huge building located a few hundred yards uphill from the Pentagon. It has enough room for 6,000 employees. Currently, about 100 Navy personnel work in it, and most of the space is used by the Marine Corps. [American Forces Press Service, 9/24/2001; Goldberg et al., 2007, pp. 14; GlobalSecurity (.org), 5/7/2011] It is the location of the Marine Corps Command Center. [Sea Power, 1/2002] Admiral William Fallon, the vice chief of naval operations, has consequently made arrangements for the Navy’s leadership and support personnel to move to the Navy Annex. [Goldberg et al., 2007, pp. 133]
Building Manager Unhappy about Moving People to Navy Annex - At around 3:00 p.m., Coneleous Alexander, a building manager at the Navy Annex, learns from one of the Marine Corps administrative managers of the plan to relocate the Navy Command Center to his building. The new command center will be set up in an area on the fourth floor that, Alexander will later say, “had been demolished for use by the build out for ballistic missiles.” [Naval Historical Center, 12/21/2001] It is unclear from Alexander’s account whether he means that missiles are being stored at the Navy Annex, or is referring to the Ballistic Missile Defense Organization, which has been housed at the Navy Annex since February this year. [US Department of Defense, 11/30/2001; US Air Force Academy, 5/2/2002] Alexander is unsure whether it is a good idea to move personnel to the Navy Annex. One reason for his uncertainty, he will say, is “the ballistic missiles” being there. He thinks a better choice would be to move people to Henderson Hall, the Marine Corps headquarters, which is located next to the Navy Annex.
Only Mission-Essential Personnel Allowed into Building - All the same, Marines start moving equipment into the Navy Annex, and maintenance crews set up portable air conditioners and exhaust fans for the Navy’s new command center there. It is decided that, due to the fear of another attack, only mission-essential personnel may enter the building. [Naval Historical Center, 12/21/2001; Goldberg et al., 2007, pp. 133] While some Navy staffs will be able to promptly return to their spaces at the Pentagon, others have to temporarily move to offices at locations that, as well as the Navy Annex, include the Washington Navy Yard and Northern Virginia’s Crystal City office complex. [Navy Times, 10/1/2001]