The North American Aerospace Defense Command (NORAD), the military organization responsible for monitoring and defending US airspace, gradually reduces the number of aircraft it has on “alert”—armed and ready for immediate takeoff—in response to the changing nature of the threats it has to defend against, so that there will be just 14 fighter jets on alert across the continental United States when the 9/11 attacks take place. [Jones, 2011, pp. 7-8]
NORAD Has 1,200 Interceptor Aircraft in 1960 – NORAD is a bi-national organization, established by the US and Canada in 1958 to counter the threat posed by the Soviet Union. [9/11 Commission, 7/24/2004, pp. 16] It is initially responsible for intercepting any Soviet long-range bombers that might attack the Northern Hemisphere. By 1960, it has about 1,200 interceptor aircraft dedicated to this task. But during the 1960s, the Soviets become less reliant on manned bombers, and shift instead to ballistic missiles. In response to this changed threat and also budget constraints, the number of NORAD interceptor aircraft goes down to about 300 by the mid-1970s.
NORAD’s Mission Changes after Cold War Ends – With the collapse of the Soviet Union and the dissolution of the Warsaw Pact in 1991, the threats NORAD has to counter change significantly. During the early 1990s, NORAD’s mission consequently changes from one of air defense to one of maintaining “air sovereignty,” which NORAD defines as “providing surveillance and control of the territorial airspace.” The new mission includes intercepting suspicious aircraft, tracking hijacked aircraft, assisting aircraft in distress, and counterdrug operations. [General Accounting Office, 5/3/1994, pp. 14-15; 9/11 Commission, 2/3/2004 
; Jones, 2011, pp. 7] As this change takes place, the number of aircraft defending American airspace is reduced. In 1987, there are 52 fighters on alert in the continental United States. [Filson, 1999, pp. 112-113] But by December 1999, there are just 14 alert fighters remaining around the continental US. [Airman, 12/1999]
Number of Alert Sites Goes Down Prior to 9/11 – The number of NORAD “alert sites”—bases where the alert aircraft are located—is also reduced in the decades prior to 9/11. During the Cold War, there are 26 of these sites. [9/11 Commission, 6/17/2004; 9/11 Commission, 7/24/2004, pp. 16] By 1991, there are 19 of them, according to Major General Larry Arnold, the commander of NORAD’s Continental US Region from 1997 to 2002. [Filson, 2003, pp. v] By 1994, according to a report by the General Accounting Office, there are 14 alert sites around the US. [General Accounting Office, 5/3/1994, pp. 1] And by 1996, only 10 alert sites remain. [Utecht, 4/7/1996, pp. 9-10]
Military Officials Call for Eliminating Alert Sites – In the 1990s, some officials at the Pentagon argue for the alert sites to be eliminated entirely. [9/11 Commission, 7/24/2004, pp. 16-17] The Department of Defense’s 1997 Report of the Quadrennial Defense Review indicates that the number of alert sites around the continental US could be reduced to just four, but the idea is successfully blocked by NORAD (see May 19, 1997). [Filson, 2003, pp. iv-v, 34-36; 9/11 Commission, 2/3/2004 ] However, three alert sites are subsequently removed from the air sovereignty mission. These are in Atlantic City, New Jersey; Burlington, Vermont; and Great Falls, Montana. [American Defender, 4/1998]
Seven Alert Sites Remain – By December 1999, therefore, there are just seven alert sites around the continental US, each with two fighters on alert. These sites are Homestead Air Reserve Base, Florida; Tyndall Air Force Base, Florida; Portland Air National Guard Base, Oregon; March Air Reserve Base, California; Ellington Air National Guard Base, Texas; Otis Air National Guard Base, Massachusetts; and Langley Air Force Base, Virginia. Only two of these sites—Otis ANGB and Langley AFB—serve the northeastern United States, where the hijackings on September 11 will take place. [Airman, 12/1999; 9/11 Commission, 7/24/2004, pp. 17]
1990-2001: NORAD Regularly Launches Fighters to Intercept Suspicious Aircraft before 9/11
Fighter jets are regularly scrambled by the North American Aerospace Defense Command (NORAD) in response to suspicious or unidentified aircraft flying in US airspace in the years preceding 9/11. [General Accounting Office, 5/3/1994, pp. 4; Associated Press, 8/14/2002] For this task, NORAD keeps a pair of fighters on “alert” at a number of sites around the US. These fighters are armed, fueled, and ready to take off within minutes of receiving a scramble order (see Before September 11, 2001). [American Defender, 4/1998; Air Force Magazine, 2/2002; Bergen Record, 12/5/2003; Grant, 2004, pp. 14] Various accounts offer statistics about the number of times fighters are scrambled: 
A General Accounting Office report published in May 1994 states that “during the past four years, NORAD’s alert fighters took off to intercept aircraft (referred to as scrambled) 1,518 times, or an average of 15 times per site per year.” Of these incidents, the number of scrambles that are in response to suspected drug smuggling aircraft averages “one per site, or less than 7 percent of all of the alert sites’ total activity.” The remaining activity, about 93 percent of the total scrambles, “generally involved visually inspecting unidentified aircraft and assisting aircraft in distress.” [General Accounting Office, 5/3/1994, pp. 4] In the two years from May 15, 1996 to May 14, 1998, NORAD’s Western Air Defense Sector (WADS), which is responsible for the “air sovereignty” of the western 63 percent of the continental US, scrambles fighters 129 times to identify unknown aircraft that might be a threat. Over the same period, WADS scrambles fighters an additional 42 times against potential and actual drug smugglers. [Washington National Guard, 1998] In 1997, the Southeast Air Defense Sector (SEADS)—another of NORAD’s three air defense sectors in the continental US—tracks 427 unidentified aircraft, and fighters intercept these “unknowns” 36 times. The same year, NORAD’s Northeast Air Defense Sector (NEADS) handles 65 unidentified tracks and WADS handles 104 unidentified tracks, according to Major General Larry Arnold, the commander of the Continental United States NORAD Region on 9/11. [American Defender, 4/1998] In 1998, SEADS logs more than 400 fighter scrambles. [Grant, 2004, pp. 14] In 1999, Airman magazine reports that NORAD’s fighters on alert at Homestead Air Reserve Base in Florida are scrambled 75 times per year, on average. According to Captain Tom Herring, a full-time alert pilot at the base, this is more scrambles than any other unit in the Air National Guard. [Airman, 12/1999] General Ralph Eberhart, the commander of NORAD on 9/11, will later state that in the year 2000, NORAD’s fighters fly 147 sorties. [9/11 Commission, 6/17/2004 ] According to the Calgary Herald, in 2000 there are 425 “unknowns,” where an aircraft’s pilot has not filed or has deviated from a flight plan, or has used the wrong radio frequency, and fighters are scrambled 129 times in response. [Calgary Herald, 10/13/2001] Between September 2000 and June 2001, fighters are scrambled 67 times to intercept suspicious aircraft, according to the Associated Press. [Associated Press, 8/14/2002]
Lieutenant General Norton Schwartz, the commander of the Alaskan NORAD Region at the time of the 9/11 attacks, will say that before 9/11, it is “not unusual, and certainly was a well-refined procedure” for NORAD fighters to intercept an aircraft. He will add, though, that intercepting a commercial airliner is “not normal.” [Air Force Magazine, 9/2011 ] On September 11, 2001, NEADS scrambles fighters that are kept on alert in response to the hijackings (see 8:46 a.m. September 11, 2001 and 9:24 a.m. September 11, 2001). [New York Times, 10/16/2001; 9/11 Commission, 7/24/2004, pp. 20, 26-27]
May 19, 1997: Military Review Suggests Cutting Fighter Protection over US; Several Bases Are Discontinued
Secretary of Defense William Cohen issues a comprehensive assessment of America’s defense requirements, called the Report of the Quadrennial Defense Review (QDR). This is a six-month analysis of the “threats, risks and opportunities for US national security,” and reviews all aspects of the US defense strategy. [US Department of Defense, 5/19/1997] Among other things, the 1997 QDR outlines the conversion of six continental air defense squadrons to general purpose, training or other missions. It calls for there being just four “alert” air defense sites around the US: at Otis, Massachusetts; Homestead, Florida; Riverside, California; and Portland, Oregon. [US Department of Defense, 5/1997; Filson, 2003, pp. 348] Major General Larry Arnold, who is commanding general of NORAD’s Continental Region on 9/11, later says: “The QDR didn’t make any sense at all. [T]here was a fight just to maintain the number of alert sites that we had. We felt we could operate fairly reasonably with about ten sites and thought eight was the absolute highest risk we could take.” NORAD Commander in Chief General Howell M. Estes III has written to the Joint Chiefs of Staff that a minimum of seven alert sites are needed to maintain America’s air sovereignty. In the end, three extra alert sites are added to the four suggested in the QDR. These are at Hampton, Virginia; Panama City, Florida; and Ellington, Texas. Larry Arnold later says, “I didn’t feel particularly comfortable with seven [alert sites] because there are great large distances between the alert sites.” [Filson, 2003, pp. 36] Other bases will lose their NORAD air defense functions over the next year, including those in Fresno, California; Fargo, North Dakota; Duluth, Minnesota; Burlington, Vermont; Atlantic City, New Jersey; and Great Falls, Montana. [US Department of Defense, 5/1997] Of these closed bases, the most critical loss on 9/11 will be the Atlantic City, New Jersey base, located about halfway between New York City and Washington. Boston air traffic control, apparently unaware the base has lost its air defense function will try and fail to contact the base shortly after learning about the first hijacking of the morning, Flight 11 (see (8:34 a.m.) September 11, 2001).
December 1997-2001: Number of Alert Air Bases Inadequate to Protect against Airborne Terrorism, NORAD Commander Says
Major General Larry Arnold, who became commander of the Continental United States NORAD Region (CONR) in December 1997, fights to preserve the resources assigned to US air sovereignty (see May 19, 1997 and Late August 2001). To emphasize the need for air bases with fighter jets on alert, Arnold frequently gives a presentation describing “asymmetric” threats and including a slide featuring Osama bin Laden. As Arnold will later recall: “[W]e thought that the biggest threat to the US in the briefing that I always gave… was going to come from an asymmetric threat, from a terrorist or a rogue nation, or maybe associated with the drug cartels to some degree. The picture that we used to have on one of our slides there, dating all the way back to 1997 and 1998, was Osama bin Laden.” [Filson, 2002] Colonel Alan Scott, who serves under Arnold at CONR, will later describe the “El Paso example” that Arnold uses to illustrate the need for more alert sites. Scott says: “We had fairly large gaps between our seven alert sites pre-9/11. The largest was between Riverside, CA, and Houston, TX. El Paso, TX, was in the middle of those two alert sites. There was no perceived ‘military’ threat from Mexico. As the threat of terrorism arose, General Arnold began to use the example in his talks to various groups. The example was that if a terrorist called and said in one hour he would overfly El Paso, TX, and spray deadly gas, we would watch it live on CNN because we could not get aircraft to that location in time to stop the attack.” [Filson, 7/14/2002]
Between 1998 and 2001: Pentagon Official Concerned about Plane Being Used as a Weapon
A Defense Department official expresses concern about the possibility of an aircraft being used as a weapon to cause massive damage.
At some point during his tenure as commander of the Continental United States NORAD Region (CONR), Major General Larry Arnold briefs Deputy Under Secretary of Defense for Advanced Technology Joseph Eash about proposed cruise missile defense initiatives. Arnold suggests to Eash the scenario of a cruise missile with a weapon of mass destruction being launched into the US. But Eash is concerned about an attack carried out using a plane that takes off within the US. As Arnold will later recount, Eash tells him, “I’m worried about someone taking an airplane off from within the US and using it as a weapon of mass destruction.” Arnold will comment, “I don’t think he envisioned someone hijacking an airliner and crashing it into the World Trade Center, but I think he envisioned a light airplane or business jet that had been stolen, either to drop some chemicals or biological agents, or maybe even to crash it.” [Filson, 2002]
1999: Air Force Study Warns against Neglecting Air Sovereignty; Threat of Terrorism Highlighted
As the military community is discussing the future of continental air defense in a post-Cold War world (see May 19, 1997), Major General Larry Arnold, the commander of the 1st Air Force, orders a study to review the Air Force’s air sovereignty mission. At his request, Major General Paul Pochmara forms a 12-member roles and mission (RAM) team to gather information and ideas on the subject. The team has a one-hour presentation that outlines the military’s responsibility for protecting the nation’s air sovereignty. Major General Mike Haugen, a member of the team, will later say that the group discusses everything from technology to the future of the air sovereignty mission to the terrorist threat. Haugen will say: “We made some pretty bold predictions in our briefing.… In fact, it included a photo of Osama bin Laden as the world’s most dangerous terrorist.… We didn’t predict how the terrorists would strike but predicted they would strike.” [Filson, 2003, pp. 37-38] A 9/11 Commission memorandum will add, “Osama bin Laden is featured on the cover of the brief developed by the RAM team, and he figures prominently in the study.” Colonel Alan Scott of the Continental US NORAD Region will tell the Commission: “As we started talking about Osama bin Laden, the examples we gave in our mission brief were the first WTC bombing, the Tokyo subway, Oklahoma City bombing, and Atlanta Olympics. What we did was connect those dots. The conclusion we drew was that we had a viable threat.” [9/11 Commission, 6/9/2004]
February 2000: Fear of Airborne Terror Attack Keeps Air Defense Chief ‘Awake at Night’
Major General Larry Arnold, the commander of the 1st Air Force whose mission includes the protection of the continental US against air attacks, tells the Associated Press that he is deeply worried by the possibility of an airborne terrorist attack. He says: “I lie awake worrying. It is one thing to put a truck inside the twin trade towers and blow it up. It is quite another to be able to fly a weapon across our borders. That is an attack, a direct attack, an unambiguous attack from outside our country.” In 1999, a study commissioned by Arnold emphasized the continued importance of the Air Force’s air sovereignty mission and the threat of terrorism (see 1999). [Associated Press, 2/1/2000; Associated Press, 8/2/2002; Filson, 2003, pp. 92] As one of the top commanders of NORAD, Arnold will play a pivotal role on the morning of 9/11 (see (8:42 a.m.) September 11, 2001, (10:08 a.m.-10:10 a.m.) September 11, 2001, and 10:31 a.m. September 11, 2001). [Code One Magazine, 1/2002; 9/11 Commission, 7/24/2004, pp. 20, 42]
September 2001: Fighters from Langley Air Force Base, Virginia, Deployed to Saudi Arabia for Operation Southern Watch
At the time of the 9/11 attacks, the 94th Fighter Squadron, which is stationed at Langley Air Force Base in Virginia, is away on a 90-day combat deployment to Saudi Arabia for Operation Southern Watch, to enforce the no-fly zone over southern Iraq. Two days before 9/11, on September 9, the 27th Fighter Squadron, which is also stationed at Langley AFB, returns from Saudi Arabia, where it has been performing the same mission. [BBC, 12/29/1998; Air Force Association, 10/2/2002; 1st Fighter Association, 2003] The 94th and 27th Fighter Squadrons are two of the three F-15 fighter squadrons that are part of the 1st Fighter Wing, which is the “host unit” at Langley AFB. The third of these is the 71st Fighter Squadron. Between them, the three squadrons have 54 “primary assigned” F-15C fighter jets. [Langley Air Force Base, 11/2003; GlobalSecurity (.org), 2/12/2006] On September 11, most of the F-15s of the 71st FS are also away from base, for the Red Flag exercise in Nevada (see (Late August-September 17, 2001)). [Virginian-Pilot, 9/24/2001; Langley Air Force Base, 9/15/2006]
Langley Jets Not Part of NORAD Alert Unit – Langley Air Force Base, which is 130 miles south of the Pentagon, is one of two “alert sites” that NORAD’s Northeast Air Defense Sector (NEADS) can call upon to get jets quickly launched. However, the F-15s of the 1st Fighter Wing are not involved in this mission. Instead, that task belongs to the North Dakota Air National Guard’s 119th Fighter Wing, which has a small detachment at Langley AFB and keeps two fighter jets there ready to take off when required. [USA Today, 9/16/2001; Air Force Magazine, 2/2002; 9/11 Commission, 7/24/2004, pp. 17; Spencer, 2008, pp. 114] Despite not being part of the NORAD alert unit, aircraft from the 1st Fighter Wing are involved in the military response to the 9/11 attacks. Jets belonging to the 27th FS are airborne within two hours of the attacks, “providing protection for the National Command Authority and the rest of the nation’s civilian and military leadership.” [Air Force Association, 10/2/2002] And F-15s belonging to the 71st FS are launched from Langley AFB following the attacks, to patrol the skies of the East Coast. [Langley Air Force Base, 1/2005; 1st Fighter Association, 3/14/2006]
Possible Effect on 9/11 Response – Whether the deployment of the 94th Fighter Squadron to Saudi Arabia diminishes Langley AFB’s ability to respond on 9/11 is unknown. However, Air Force units are cycled through deployments like Operation Southern Watch by the Aerospace Expeditionary Force (AEF) Center, which is at Langley Air Force Base. And according to NORAD Commander Larry Arnold, “Prior to Sept. 11, we’d been unsuccessful in getting the AEF Center to be responsible for relieving our air defense units when they went overseas.” [Air Force Print News, 6/2000; GlobalSecurity (.org), 12/21/2002; Filson, 2003, pp. 99]
September 7-8, 2001: High Level Air Force Discussions Call for Dismantling NORAD’s Alert Sites
The future of “continental air sovereignty” over America is in doubt. Discussions at the Air Force’s highest levels call for the dismantling of NORAD’s seven “alert” sites around the US and its command and control structure. [Filson, 2003, pp. 149] Maj. Gen. Larry Arnold, the commanding general of NORAD’s Continental Region, will later add that “the secretary of the Air Force, James G. Roche, stated that he and the then chief of staff of the Air Force, General John Jumper, had decided to withdraw funding for air defense, and they had made that decision on September 7, 2001.” [Spencer, 2008, pp. 289] Earlier in the summer of 2001, “a reduction in air defenses had been gaining currency in recent months among task forces assigned by [Defense Secretary Donald] Rumsfeld to put together recommendations for a reassessment of the military” (see Summer 2001). [Los Angeles Times, 9/15/2001]
8:20 a.m. September 11, 2001: NEADS Commander Marr and CONR Commander Arnold Discuss NORAD Training Exercise
Colonel Robert Marr, the battle commander at NORAD’s Northeast Air Defense Sector (NEADS), speaks over the phone with Major General Larry Arnold, the commander of the Continental United States NORAD Region (CONR), about the day’s training exercise. Marr is in the battle cab at NEADS, in Rome, New York, while Arnold is at the CONR headquarters at Tyndall Air Force Base, Florida. [9/11 Commission, 1/23/2004 ; 9/11 Commission, 2/2/2004 ] All of NORAD, including NEADS, is currently participating in the major annual exercise, Vigilant Guardian. [Northeast Air Defense Sector, 8/23/2001; Arkin, 2005, pp. 545; Defense Video and Imagery Distribution System, 9/8/2011] Marr has just been in a staff meeting, and now checks in with Arnold to make sure their communication lines are up and ready for the exercise. [Grant, 2004, pp. 19] Marr tells Arnold that the personnel on the NEADS operations floor are ready to begin the exercise. Marr will tell the 9/11 Commission that his “primary communication” on this day “is to higher headquarters,” presumably meaning Arnold. However, the two men are not on a continual open line. [9/11 Commission, 1/23/2004 ] Arnold will tell the Commission that he and Marr “did not stay on the line continually, but spoke when information needed to be passed,” throughout the day. [9/11 Commission, 2/3/2004 ]
