Aerospace Defense Command

Aerospace Defense Command is an inactive United States Air Force Major Command. Established in 1946 under the United States Army Air Force, its mission was to organize and administer the integrated air defense system of the Continental United States (CONUS), exercise direct control of all active measures, and coordinate all passive means of air defense.

The command was inactivated on 31 March 1980.

Overview
The mission of air defense is a major foundation of the United States Air Force. In 1916, Alexander Graham Bell warned about the possibility of airship raids on the United States. For the next 25 years, experts studied the problem of air defense and lay the foundation for the future.

The War Department established an "Air Defense Command" as part of the Army Air Corps on 26 February 1940. This command, operating under the control of the United States First Army Commander from 2 March 1940, to 9 September 1941, engaged in planning for air defense of the Continental United States.

Before the United States entered World War II, air defense was divided among the four GHQ Air Force districts later, First, Second, Third, and Fourth Air Forces based in the United States. Initially, there was a sizeable effort to defend the country from aerial attack. In mid-1944, when the threat of air attack seemed negligible, this air defense organization was disbanded.

Subsequently, no real air defense organization existed until the second Air Defense Command was established in 1946 as a major command of the Army Air Forces (AAF). However political issues within the Pentagon were not to be overlooked. There was concern within the Air Force that funds to create an "impenetrable air defense" would be obtained by siphoning money away from Strategic Air Command's mission of nuclear deterrence. Apart from the intramural disputes, The Air Force battles with the Army over control of Surface-to-Air missiles and other issues were particularly intense.

The initial mission of Air Defense Command was to stop a handful of conventionally armed piston engine-powered bombers on a one-way mission, flying a predictable course. The threat swiftly grew to the prospect of an attack by hundreds of turboprop and jet bombers armed with thermonuclear weapons and attacking from different directions. Meeting such a threat required the creation of a huge system. It consumed billions of dollars. It required leadership, foresight, and brilliant science.

In the early 1960s, however, aircraft air defense was overtaken by events, as USAF shifted its emphasis away from intercepting bombers and toward the detection of Intercontinental Ballistic Missiles (ICBM)s. Robert S. McNamara, Secretary of Defense in the Kennedy and Johnson Administrations, concluded that the ICBM problem was so overwhelming that it rendered relatively inconsequential the threat of Soviet bomber attack. With the rise of the ICBM, emphasis on air defense against bombers went into a sharp decline. Air Defense Command was redesignated as Aerospace Defense Command (ADCOM) in 1968 to reflect that fundamental mission change.

The Aerospace Defense Command declined after 1979 when its resources were divided between Tactical Air Command and Strategic Air Command. Under TAC, the Air National Guard and Air Force Reserve gradually assumed more and more of the air defense mission. In 1980, ADCOM was inactivated. Some functions of the command passed to the Aerospace Defense Center, a direct reporting unit assigned to Headquarters, NORAD that inactivated on 1 October 1986.

Today, ADC's proud heritage is maintained by NORAD, Air Combat Command, the Air National Guard, and the Air Force Reserve.

Origins
In spite of the outbreak of World War II in Europe during September 1939, the War Department did not consider air defense of the United States a major concern. This was because military planners did not envisage a large-scale bomber assault on this country if the United States became involved in active combat. Most airmen agreed with General George C. Marshall when he said in May 1940 that the defense of the country could be assured by denying a potential enemy bases in the Western Hemisphere.

Nevertheless, on the recommendation of General Henry H. Arnold, the Chief of the United States Army Air Corps, the War Department established an "Air Defense Command" on 26 February 1940. As a component of the U.S. First Army, its mission was to plan for and execute the air defense of the continental United States. It consisted of personnel from the Air Corps, the Coast Guard and Army Signal Corps.

At a conference held in February 1941, General Marshall assigned the responsibility for air defense to the new continental Air Forces being developed under GHQ Air Force, each of which contained an "Interceptor Command". The Interceptor Commands were charged with air defense of their areas, but were subject to the overall supervision of four new Numbered Air Forces, which were aligned with the four Army defense areas, which were vested with overall defense responsibility. These districts were:


 * Northeast Air District - assigned to First Air Force
 * Northwest Air District - assigned to Second Air Force
 * Southeast Air District - assigned to Third Air Force
 * Southwest Air District - assigned to Fourth Air Force

RADAR Development
The development of early warning RADAR (radio detection and ranging) technology in the 1930s made effective air defense possible. By December 1936 the Signal Corps successfully tracked an aircraft to a distance of seven miles using short-pulse emission of radio waves. Air Corps representatives saw the value of the device for early warning. Service trials of the first early warning RADAR, the SCR-270, were held late in 1939, with the device being officially adopted in May 1940.

The entry of the United States in World War II resulted in a major expansion of air defense facilities, especially on the two ocean coasts. Ninety-five radar stations were eventually completed: 65 on the Pacific Coast and 30 on the Atlantic, although about 75 was the maximum number operational at any one time. The principal radars (known as: Signal Corps Radio) in use during the war were the SCR-270 (mobile) and the SCR-271 (fixed), with ground control intercept radar (SCR-588) being added during 1943 for close-in coverage (up to 50 miles) for tracking and controlling fighters from the ground.

Ground observers
The World War II Air Defense Command established a ground observer network in air defense exercises in 1940-1941 which greatly facilitated the War Department's organization of the AAF Ground Observer Corps in 1942. The information network grew-during the war to a maximum of 15 information centers along both coasts and four standby centers along the Gulf of Mexico coastline, with a total of 14,000 observation posts and an estimated 1,500,000 civilian volunteers enrolled.

Interceptor aircraft
The shortage of fighter planes in the early part of the war proved a serious handicap to the air defense effort. However, the situation improved during 1942 and 1943 with the availability in quantity of the P-38 Lightning and P-47 Thunderbolt, which equipped units which were attached to Air Defense Fighter Wings over major cities along the east and west coasts as part of their training for overseas combat duty.

Still, until the introduction of the P-61 Black Widow, the lack of all-weather day/night aircraft made the success of interception at night, or in inclement weather, highly doubtful. The P-61 however, was not made available for air defense operations in the United States during the war, its need in the overseas combat theaters taking priority.

Anti-Aircraft artillery
Anti-aircraft artillery (AAA) provided for local defense. AAA underwent drastic changes during the war, with unified AAA commands emerging on both coasts after the Pearl Harbor Attack. After considerable controversy the control of AAA was placed under the Army Air Forces interceptor commands.

This elaborate air defense system fortunately never had to deal with a major air attack. Until the Battle of Midway in June 1942, air defenses remained on a high alert, but after the naval battle, only occasional alerts were called: As the threat decreased, the defenses gradually reduced, with the focus on the four Air Forces in the United States (Zone of Interior "ZI") being the organization and training of combat units and replacement personnel for deployment to overseas theaters.

The ADC Air District structure was abolished in April 1944 along with Air Defense Command. The numbered air forces and their training mission was turned over to the USAAF Continental Air Forces training command. The Ground Observer Corps was dissolved, the radar net reduced in size, and the Air Defense Fighter Wings being reduced to administrative units, not equipped or manned. By war's end on the east coast three control centers and nine radar stations remained. On the west coast three control centers and 22 radars were active.

With demobilization in 1945, the air defenses of the United States had virtually ceased to exist.

Associated units

 * I Interceptor Command  (1st Air Force)
 * II Interceptor Command (2d Air Force)
 * III Interceptor Command (3d Air Force)
 * IV Interceptor Command (4th Air Force)

First Air Force air defense fighter wings:
 * Boston Fighter Wing
 * New York Fighter Wing
 * Norfolk Fighter Wing
 * Philadelphia Fighter Wing

Fourth Air Force air defense fighter wings:
 * Los Angeles Fighter Wing
 * San Diego Fighter Wing
 * San Francisco Fighter Wing
 * Seattle Fighter Wing

Cold War History
The second iteration of Air Defense Command (ADC) was established on 21 March 1946 as a component of the United States Army Air Forces. General Carl Spaatz had undertaken a major reorganization of the Army Air Forces after the end of World War II to incorporate many of the lessons learned. His reorganization included the establishment of three new combat commands in the United States: Strategic Air Command (soon known everywhere as SAC), to provide a long-range striking force capable of bombardment operations in any part of the world: Tactical Air Command (TAC), to support the operations of ground forces, and Air Defense Command (ADC), to provide for the air defense of the United States.

Postwar era
Air Defense Command was constituted on 21 March 1946, and was activated and headquartered at Mitchel Field, New York, on 27 March 1946. It assumed control of the 414th Night Fighter Squadron, which was an un-manned and un-equipped administrative organization, and the 425th Night Fighter Squadron, which was manned by one officer and two enlisted men. Two bases, Mitchel Field, New York and Hamilton Field, California, were assigned to ADC. Two numbered air forces, the First Air Force (Mitchel) and Fourth Air Force (Hamilton) were allocated.

Shortly afterwards, on 10 June, the ADC mission was expanded to the extent that ADC was required to coordinate within the United States the means available from other services for air defense, such as Naval and Marine aircraft units temporarily shore-based.

In 1947, the 505th Aircraft Control and Warning Group, the first postwar aircraft control and warning organization, was activated at McChord Field, Washington on 21 May. The newly established United States Air Force granted ADC the authority to use the fighter and radar forces of SAC, TAC and the Air National Guard in the event of a national emergency. Most air defense units at the time were part of the Air National Guard. Four additional numbered air forces, the Second (Fort Crook, Nebraska); Tenth (Brooks Field, Texas); Eleventh (Olmstead Field, Pennsylvania), and the Fourteenth Air Force (Orlando Air Base, Florida) were assigned. (Eleventh Air Force was inactivated on 1 July 1948. It has no relationship to the current or previous 11th Air Force).

At the end of World War II a number of factors operated to belittle the need for elaborate air defenses. The result was that the construction of a modern air defense system lagged. However, with the Cold War breaking out between the United States and the Soviet Union in 1948, a more urgent note was struck in air defense. Radars were removed from storage and deployed along the Atlantic and Pacific coasts.

ADC activated two Divisions, the 25th Air Division at Silver Lake Air Warning Station, Washington on 25 October 1948 and the 26th Air Division at Roslyn Air Warning Station, New York 16 November. Both of these organizations were active for over 40 years in the air defense of the United States, being inactivated after the end of the Cold War. Their successor organizations became the current Eastern (EADS) and Western Air Defense Sector (WADS) of today's Continental United States NORAD Region (CONR).

Continental Air Command
On 1 December 1948 Continental Air Command (ConAC) was created and given the mission of air defense. Both ADC and Tactical Air Command were reduced to operating agencies under ConAC which consisted of a small staff of planners. TAC fighter units while in the United States assumed an air defense mission which augmented the meager resources of ADC.

In March 1949, the six numbered air forces inherited from ADC were relieved of their air defense responsibilities. Two new units, the Eastern and Western Air Defense Liaison Groups were created in their place. In September, these provisional units were re-designated as the Eastern Air Defense Force and Western Air Defense Force, under which all atmospheric air defense units (Radar and Interceptor) were placed, divided by the 103rd meridian west.

During 1949 and early 1950, steady strides were made in air defense. In March 1949, Congress authorized the construction of a "permanent" radar system along the coasts and land borders of the United States. Following the explosion of a nuclear weapon by the Soviet Union in August 1949, the Air Force issued requirements for an operational air defense system by 1952, and the building of the permanent radar network was accelerated.

Air Defense Command
The outbreak of the Korean War in June 1950 underlined the need for increased air defense precautions. In addition, the perceived threat of an airborne atomic attack by the Soviet Union with its Tu-4 copy of the B-29 or Tu-95 strategic bomber force led to the separation of Air Defense Command from ConAC, and its re-establishment as an Air Force major command to counter the perceived Soviet threat.

Air Defense Command was officially re-established as a major air command on 1 January 1951 at Mitchel AFB, New York. The command headquarters was moved to Ent AFB, Colorado on 8 January 1951. ConAC transferred to ADC 21 active-duty fighter squadrons and 37 Air National Guard fighter squadrons operationally gained by ADC if activated. It was also assigned the 25th, 26th 27th and 28th Air Divisions (Defense)

With the reestablishment ADC as a major command (as well as TAC), ConAC's mission became one of administering the Air Force Reserve.

Early warning Radars
Early-warning radars are a fundamental necessity of the United States air defense system. As the Soviet Cold War threat became generally recognized, so did a requirement for adequate early warning. In the earliest effort to provide it, the USAF came up with a system in 1947 known as "Radar Fence Plan," which called for 411 radar stations and 18 control centers and was projected to cost $600 million.

The cost of the plan clearly exceeded the Air Force ability to pay, and planners tried to develop a less expensive version. The answer was something that became known as the "Permanent System." It was to consist of 85 radar stations and 11 control centers, in the United States and Alaska. The cost was estimated to be about $116 million, spread over the period 1949-50. It became fully operational in April 1953.

However, the Air Force was loath to ignore the immediate threat, and it built a temporary system, sarcastically but aptly called "Lashup." It comprised 43 sites by 1950. The system used World War II AN/CPS-5 search radar systems that were deficient in range and in low-altitude detection capability. In addition, 36 Air National Guard fighter units were called to active duty for the mission.

Lashup had the great value of introducing the US again to the concept of a radar air defense system. ADC was reinstated as a full major command in January 1951, and ADC headquarters established at Ent AFB, Colorado. By 1953, a modern United States continental system of Ground Control Interception (GGI) Radar stations had been completed and additional radar units were programmed to blanket the country with medium and high-altitude radar cover. Domestically the gaps were filled by additional Federal Aviation Administration (FAA) radar stations and the organization of a million American men and women into the Ground Observer Corps (GOC) which served the nation until it was disbanded in 1959.

Work was begun in 1953 to erect a number of off-shore radars platforms bristling with radar equipment and embedded in the ocean bed known as Texas Towers to extend the range of RADAR into the Atlantic Ocean to cover the northern approach routes far out to sea. One of the Texas Towers (TT-4) collapsed into the Atlantic Ocean with significant loss of life in January 1961. The tragedy of TT-4, as much as anything else, sealed the fate of the others. While both remaining towers were immediately checked for safety and structural strength, and pronounced sound in this regard, their days were numbered. The entire project was ended in 1963, and the remaining facilities were decommissioned and sunk in 1964.

During the mid-1950s, the nation's defense planners devised the idea of extending the wall of powerful land-based radar seaward with Airborne early warning and control units. This was done by equipping two wings of Lockheed RC-121 Warning Star aircraft, the 551st Airborne Early Warning and Control Wing, based at Otis Air Force Base, Massachusetts, and the 552nd AEWCW, based at McClellan Air Force Base, California, one wing stationed on each coast. The RC-121s, EC-121s and Texas Towers, it was believed, would contribute to extending contiguous east-coast radar coverage some 300 to 500 miles seaward. In terms of the air threat of the 1950s, this meant a gain of at least 30 extra minutes warning time of an oncoming bomber attack.

As the USAF prepared to deploy the Tactical Air Command E-3 Sentry in the later 1970s, active-duty units were phased out EC-121 operations by the end of 1975. All remaining EC-121s were transferred to the Air Force Reserve, which formed the 79th AEWCS at Homestead Air Force Base, Florida in early 1976. The active duty force continued to provide personnel to operate the EC-121s on a 24-hour basis, assigning Detachment 1, 20th Air Defense Squadron to Homestead AFB as associate active duty crews to fly the Reserve-owned aircraft. Besides monitoring Cuban waters, these last Warning Stars also operated from NAS Keflavik, Iceland. Final EC-121 operations ended in September 1978.

Interceptor Aircraft
The growth and development of the ADC air defense system grew steadily throughout the Cold War era. From four day-type fighter squadrons (FDS) in 1946, the ADC interceptor force grew to ninety-three (93) active Air Force fighter interceptor squadrons, seventy-six (76) Air National Guard fighter interceptor squadrons, several Naval fighter squadrons, USAF and USN airborne early warning squadrons, radar squadrons, training squadrons and numerous support units that have played important roles in our nation's defense.

When the Cold War began, bomber technology was ascendant and would continue to be so for more than a decade. The first ADC interceptor, the P-61 Black Widow did not have the capabilities to engage the Soviet Tu-4 bomber. Its successor, the F-82 Twin Mustang, was even more disappointing. It took a long time to get into production and did not perform well in inclement weather.

The early jet fighters, such as the F-80 Shooting Star and F-84 Thunderjet, lacked all-weather capability and were deemed useless for air defense purposes. Much hope was placed on two jet-powered interceptors, the XP-87 Blackhawk and the XP-89 Scorpion. (Designations changed to XF-87 and XF-89.) They, in their turn, proved to be inadequate. The XF-87 was cancelled and the Scorpion had to undergo extensive redesign.

The first-generation jets gave way to all-weather dedicated interceptor jets. The F-94 Starfire was pressed into service as an "interim" interceptor. North American in 1949 pushed an interceptor version of the Sabre, the F-86D. Despite the demands its complexity made upon a single pilot, the F-86D was backed by senior Air Force officials. Some 2,504 would be built and it would in time be the most numerous interceptor in the Air Defense Command fleet, with more than 1,000 in service by the end of 1955

The F-86D was not ideal, however, for its afterburner consumed a great deal of fuel in getting it to altitude, and the pilot was overburdened by cockpit tasks. The F-89D was modified to accept AIM-4 Falcon guided missiles (F-89H) and AIR-2 Genie atomic warhead rockets (F-89J) as armament. The F-86D was modified (F-86L) to include the SAGE data link, thereby permitting more precise automatic control from the ground. The F-86L and F-89H became available in 1956, the F-89J in 1957.

Even more advanced were the Century Series supersonic interceptors. First was the F-102A Delta Dagger, which appeared in 1956. The F-104A Starfighter came along in 1958. The F-101B Voodoo and F-106 Delta Dart were first received by ADC during the first half of 1959. By 1960, the ADC interceptor force was composed of the F-101, F-104, F-106, and the F-102. The North American F-108 Rapier was the first proposed successor to the F-106. It was to be capable of Mach 3 performance and was intended to serve as a long-range interceptor that could destroy attacking Soviet bombers over the poles before they could get near US territory. It was also to serve as the escort fighter for the XB-70 Valkyrie Mach-3 strategic bomber, also to be built by North American. The Air Force expected that the first F-108A would be ready for service by early 1963. An order for no less than 480 F-108s was anticipated.

However, by mid-1959, the Air Force was already beginning to experience some doubts about the high cost of the Rapier program. The primary strategic threat from the Soviet Union was now perceived to be its battery of intercontinental ballistic missiles instead of its force of long-range bombers. Against intercontinental ballistic missiles, the F-108A interceptor would be completely useless. In addition, the Air Force was increasingly of the opinion that unmanned intercontinental ballistic missiles could accomplish the mission of the B-70 Valkyrie/F-108 Rapier combination much more effectively and at far lower cost. Consequently, the F-108A project was cancelled in its entirety on 23 September 1959, before any prototypes could be built.

The work on the F-108 Rapier did not entirely go to waste. The work that Hughes did on the AN/ASG-18 radar was later transferred over to the Lockheed YF-12A interceptor project, and the GAR-9 Falcon (redesignated AIM-47A in 1962) missile originally developed for the F-108A was used to arm the YF-12A. The Lockheed F-12 Mach 3 interceptor of the mid-1960s was the final interceptor planned by Air Defense Command for purchase and deployment. It had its origin in the top-secret A-12 reconnaissance aircraft which had been designed by Lockheed at Central Intelligence Agency request as a successor to the U-2. Three prototype YF-12As served initially with the 4786th Test Squadron at Edwards AFB. The USAF was sufficiently impressed with the performance of the YF-12A that on 14 May 1965 they ordered a total of 93 definitive F-12B aircraft into production and Congress voted $90 million toward the project. However, Secretary of Defense Robert McNamara saw no need for the F-12B due to the development of ICBMs and the diminishing threat of Soviet bombers attacking United States cities. Another reason given by McMamara for cancelling the F-12 was that the expanding war in Southeast Asia was consuming all available funds in the USAF budget. This was, of course, before the Soviets developed the Tupolev Tu-22M and Tupolev Tu-160 supersonic strategic bombers which were at least an even match to the fastest ADC F-106 Delta Dart.

The YF-12As served primarily in various and sundry operational evaluation projects throughout the remainder of the 1960s. In February 1963, Lockheed undertook redesign of the basic A-12 with additional fuel tankage, broader forward nose chines, and the provision for inflight refueling and a seat for a second crewman. This eventually emerged as the SR-71 Blackbird.

In 1968, ADCOM began the phaseout of the F-101 and F-102 interceptors from active duty units. George W. Bush, later President of the United States, flew the F-102 as part of his Air National Guard service in the late 1960s and early 1970s. The F-106 Delta Dart remained, as it was considered by many as being the finest all-weather interceptor ever built. It was the primary air defense interceptor aircraft for the US Air Force during the 1970s through the early 1980s. It was also was the last dedicated interceptor in U.S. Air Force service to date. It was gradually retired during the 1980s, though the QF-106 drone conversions of the aircraft were used until 1998 as aerial targets under the FSAT program.

Interceptor gunnery training
B-57E Canberra dedicated Air Defense Command target towing aircraft were used for training of F-86D Sabre, F-94C Starfire, and F-89D Scorpion interceptors firing 2.75-inch Mk 4/Mk 40 Folding-Fin Aerial Rockets. Due to the nature of air-to-air weapon training requiring a large amount of air space, only a few locations were available for practice ranges. ADC assigned these aircraft to bases close to these large, restricted areas, and fighter-interceptor squadrons deployed to these bases for this type of "hot fire" training which took place in these ranges.

The gunnery schools were located at Yuma AFB, Arizona (17th TTS), and later moved to MacDill AFB, Florida where the training continued over the Gulf of Mexico. With the move to Florida, the 3d TTS was formed at George AFB, California which performed training over the Mojave Desert in Southern California. Additional units were located at Biggs AFB, near El Paso, Texas (1st TTS) and the 4756th TTS was located at Tyndall AFB, Florida to support the Fighter Weapons Center located there. ADC also supported overseas training at Johnson AB, Japan (6th TTS). From Johnson AB, B-57Es deployed to Clark AB, Philippines; Andersen AFB, Guam, Naha AB, Okinawa and Itazuke AB, Misawa AB and Yokota AB, all in Japan for training of the interceptor squadrons assigned to those bases. The 6th TTS was inactivated by late 1957 and the Canberra trainers were designated a flight of the 8th Bombardment Squadron at Johnson AB. In Europe, USAFE supported a squadron of B-57E gunnery trainers at Wheelus AB, Libya where European-based interceptors deployed for "live firing" over the vast desert range there.

To provide challenges for interceptors, The B-57Es towed styroforam, bomb-shaped radar reflectant targets. These could be towed at higher altitudes than the high-drag 45' banners but hits could still be scored on them. By 1960, the rocket firing interceptors were giving way to F-102 Delta Dagger interceptors firing heat-seeking AIM-4 Falcon air-to-air missiles. This made the target towing mission of the B-57E obsolete, and the B-57Es were adapted to electronic countermeasures and faker target aircraft (EB-57E) (see below).

In order to cover combat losses in the Vietnam War caused by two major ground explosions, twelve B-57Es were reconfigured as combat-capable B-57Bs at the Martin factory in late 1965 and were deployed to Southeast Asia for combat bombardment operations. Six other B-57Es were converted to RB-57E "Patricia Lynn" tactical reconnaissance aircraft in 1966 during the Vietnam War, operating from Tan Son Nhut Air Base until 1971.

Weapons Systems Integration


The development of effective Ground Intercept Radar stations, and the deployment of interceptor squadrons was soon augmented by more-effective systems whose inputs would be fed to one of the bigger gambles of the period—the Semi Automatic Ground Environment (SAGE) system, designed to control fighters and fight the air defense battle.

As the performance of radars and weapons improved, the reflexes of the men who operated them proved much too slow, By 1953, steps had been taken develop an electronic command and control network. SAGE had begun as a concept in the Air Defense Systems Engineering Committee, headed by eminent Massachusetts Institute of Technology scientist George E. Valley. Valley foresaw that computers would develop to the point that they could be used to control an air defense system. He was right, and he was backed by ADC commanders throughout the years.

SAGE was the nerve center of continental air defense until replaced in the early 1980s. It was an automated control system linking Air Force (and later FAA) General Surveillance Radar stations into a centralized center for Air Defense, intended to provide early warning and response for a Soviet nuclear attack. This automated control system was used by NORAD for tracking and intercepting enemy bomber aircraft.

In later versions, the system could automatically direct aircraft to an interception by sending commands directly to the aircraft's autopilot. SAGE was tremendously important. It led to huge advances in online systems and interactive computing, real-time computing, and data communications using modems. It is generally considered to be one of the most advanced and successful large computer systems ever developed.

The first SAGE Direction Center opened at McGuire AFB, New Jersey on 1 July 1958, and was rapidly joined by others in the eastern and northern United States during 1959 and 1960. By the end of the decade the blockhouses of the SAGE System could be seen across the nation.

By the time it was fully operational the Soviet bomber threat had been replaced by the Soviet missile threat, for which SAGE was entirely inadequate. However, as long as the Soviet Union maintained an active intercontinental bomber force, the system was active, and ready to respond to any incursion of North American airspace. SAGE was inactivated and replaced in 1983 by the Joint Surveillance System (JSS).

Anti-Aircraft Missiles


Alongside the manned interceptors was the CIM-10 Bomarc supersonic surface-to-air missile which-first entered the ADC inventory in September 1959. The BOMARC was a joint United States of America-Canada effort between 1957 and 1971 to protect against the USSR bomber threat. It involved the deployment of tactical stations armed with Bomarc missiles along the east and west coasts of North America and the central areas of the continent.

The supersonic Bomarc missiles were the first long-range anti-aircraft missiles in the world. They were capable of carrying conventional or nuclear warheads. Their intended role in defence was in an intrusion prevention perimeter. Bomarcs aligned on the eastern and western coasts of North America would theoretically launch and destroy enemy bombers before the bombers could drop their payloads on industrial regions.

The BOMARC interceptor missile was deployed to a number of sites along the eastern seaboard and northern border. When the BOMARC missile was phased out in the late 1960s, the SAGE guidance system (TDDL, Time-Division Data Link) continued to be used for sending commands to Army Nike-Hercules Integrated Fire Control (IFC) centers and interceptor autopilots.

Defense Systems Evaluation

 * See also: List of United States Air Force defense systems evaluation squadrons

"Faker", or simulated target aircraft were flown as simulated target aircraft to exercise GDI stations, interceptor squadrons and SAGE control centers. Initially using modified B-25 Mitchell and B-29 Superfortress bombers, the aircraft would fly attack profile missions at unexpected, random times and attempt to evade coverage by flying at low altitudes and randomly flying in different directions to confuse interceptors. The aircraft were modified to carry electronic countermeasures (ECM) gear to attempt to confuse radar operators. In 1957, the propeller-driven aircraft were phased out and replaced by Martin B-57 medium bombers which were being phased out of Tactical Air Command. Initially RB-57As from reconnaissance units were modified to have their former camera bays refitted to carry out the latest ECM systems to confuse the defenders. Wing racks, originally designed for bombs, now carried chaff dispensers and the navigator position was replaced with an Electronic Warfare Officer (EWO). The modified B-57s were designated as EB-57 (E for special electronic installation).

Considerable realism would be generated into these simulated aggressor attack missions being flown by the B-57 crews. Often several EB-57s were used to form separate tracks and provide a coordinated jamming attack to complicate the testing. When inside the range of the GCI radar, and in anticipation of interception, chaff was dispensed to confuse the defense force and electronic pulses to jam radar signals were turned on. It was up to the defending interceptors and GCI stations to sort out the correct interception.

Units operating these specially equipped aircraft were designated Defense Systems Evaluation Squadrons (DSES). The 4713th Defense Systems Evaluation Squadron was stationed for training in the Northeast. The 4713th also deployed frequently to USAFE in West Germany for training of NATO forces. The other was the 4677th Defense Systems Evaluation Squadron, which concentrated on Fighter Interceptor Squadron training for units in the Western United States. In 1974, the 4713th DSES was inactivated and its EB-57s were divided between two Air National Guard units and the 4677th DSES was re-designated as the 17th Defense Systems Evaluation Squadron. This unit was inactivated in July 1979 and was the last to fly B-57s in the active duty USAF. It shared the Defense Systems Evaluation mission with the Kansas and Vermont Air National Guard. Defense Systems Evaluation operations were also carried out by the 6091st Reconnaissance Squadron, Yokota AB, Japan; later the 556th Reconnaissance Squadron and moved to Kadena AB, Okinawa. EB-57s were also deployed to Alaskan Air Command, Elmendorf AFB, Alaska, frequently.

The 134th Defense Systems Evaluation Squadron, Vermont Air National Guard, retired its last EB-57 in 1983, and the operational use of the B-57 Canberra ended.

NORAD Continental Defense


The Royal Canadian Air Force proved to be a boon partner with the United States, both in the responsibilities it assumed in the construction of the warning systems and in the provision of effective air defense squadrons. In some respects, the air defense mission was to RCAF what the nuclear deterrent mission was to USAF -its No. 1 reason for being

In the early 1950s, the two North American air forces launched construction of the Pinetree Line and completed it in June 1954. Consisting of 33 stations, it extended on both sides of the international border and provided warning and ground-control-intercept activities. The United States paid for 22 of the stations and provided personnel for 18.

Canada then constructed the Mid-Canada Line, building it entirely with its own resources. Built along the 55th parallel, the early warning system was also called the McGill Line, after the scientists at McGill University who planned and designed it. Not so much a radar warning line as an unmanned microwave fence, the line signaled when something-anything-flew over it. The Mid-Canada Line became operational in 1957 and cost approximately $220 million.

By 1954 it became apparent that the command and control of the massive North American air defense system was a significant challenge. Coordination in the United States was accomplished by a new joint-service agency of Air Force, Army and Navy personnel reporting directly to the Joint Chiefs of Staff and called the Continental Air Defense Command (CONAD).

The command and control of the massive North American air defense system was a significant challenge. Discussions and studies of joint systems between the United States and Canada had been ongoing since the early 1950s and culminated on 1 August 1957, when an agreement was made with Canada to partner in the joint effort to defend the North American continent which resulted in the North American Air Defense Command (NORAD), in which ADC continued to be the major United States component.

On 12 September joint operations commenced at Ent AFB, Colorado. A formal NORAD agreement between the two governments was signed on 12 May 1958.

Alaska and above the Arctic Circle
The Alaskan Air Command was established in 1946 with a mission of air defense of Alaska and the Aleutian Islands. With the Soviet Union less than 50 miles to the west across the Bearing Straits, Alaska was the "front line" of North American air defense. A series of Ground Control Intercept and surveillance radar stations and interceptor bases were established there in the 1950s to provide for the defense of northwest North America.

Working with Canada, USAF planners began to entertain the prospect of building a warning line in the far north, inside the Arctic Circle. High cost projections disturbed Air Force leaders, who believed the money could be better spent on bomb shelters and base dispersal efforts. However, USAF conducted experiments in conjunction with the Lincoln Laboratory of MIT and became convinced that a Distant Early Warning Line (DEW Line) was feasible. Once again working in cooperation with the RCAF, USAF in December 1954 placed a contract for the construction of the DEW Line.

The DEW Line, built along an irregular path extending from Cape Lisburne AFS, Alaska, to the west coast of Greenland, with auxiliary stations situated even further east, was a mammoth undertaking. It was the largest construction project ever attempted in the Arctic, and it required the movement of hundreds of shiploads of material and thousands of sorties by American transport airplanes. The workforce toiled day and night, seven days a week, to make the 31 July 1957, date when responsibility was to be transferred to USAF. Twenty-five lives were lost in the process. The Pinetree, Mid-Canada, and DEW Lines all were integrated into the SAGE system.

The "White Alice" communications system was built to link airborne warning and control aircraft with the DEW Line radar. Ultimately, 49 sites were built, extending along the Aleutian archipelago out to Shemya, Alaska.

Ballistic Missile Early Warning System
The success of the DEW Line for atmospheric defense of North America from an Arctic attack by Soviet aircraft smoothed the way for the development of an effective defense against the Intercontinental Ballistic Missile (ICBM) and Submarine-launched ballistic missile (SLBMs).

The Ballistic Missile Early Warning System (BMEWS), which was completed in 1963 after five years of intensive effort provided a capability of detecting missiles in flight, deep in the Soviet Union or in other similarly distant territory. The BMEWS sites included Thule AB in Greenland, Clear AFS in Alaska, and RAF Fylingdales in England. In addition, the number of radar stations had increased dramatically during the decade of the 1950s, with 300 small automatic radar sites adding coverage.

Additional radars came into being for the sole purpose of detecting, identifying, tracking, and sending back data on any SLBM. All man-made objects in earth orbit became numbers in the United States Space Surveillance Network (SPACETRACK) operated by ADC's Fourteenth Aerospace Force.

Aerospace Defense Command
As the space mission grew the command changed its name, effective 15 January 1968, to Aerospace Defense Command, or ADCOM. Under ADCOM, emphasis went to systems for ballistic missile detection and warning and space surveillance, and the atmospheric detection and warning system, which had been in an almost continuous state of expansion and improvement since the 1950s, went into decline.

BOMARC, for example, was dropped from the weapons inventory, and the F-101 and F-102 passed from the regular Air Force inventory into the National Guard. To save funds and manpower, drastic reductions were made in the number of long range radar stations, the number of interceptor squadrons, and in the organizational structure. By 1968 the DOD was making plans to phase down the current air defense system and transition to a new system which included an Airborne Warning and Control System (AWACS), Over-the-Horizon Backscatter (OTH-B) radar, and an improved F-106 interceptor aircraft.

The changing emphasis in the threat away from the manned bomber and to the ballistic missile brought reorganization and reduction in aeropace defense resources and personnel and almost continuous turmoil in the management structure. The headquarters of the Continental Air Defense Command (CONAD) and ADC were combined on 1 July 1973. Six months later in February 1973, ADC was reduced to 20 fighter squadrons and a complete phaseout of air defense missile batteries.

Continental Air Command was disestablished on 1 July 1975 and Aerospace Defense Command became a specified command by direction of the JCS. Reductions and reorganizations continued into the last half of the 1970s, but while some consideration was given to closing down the major command headquarters altogether and redistributing field resources to other commands, such a move lacked support in the Air Staff.

Inactivation
In early 1977 strong Congressional pressure to reduce management "overhead" and the personal conviction of the USAF Chief of Staff that substantial savings could be realized without a reduction in operational capability. moved the final "reorganization" of ADCOM to center stage. Two years of planning followed, but by late 1979 the Air Force was ready to carry it through. It was conducted in two phases:


 * On 1 October 1979 ADCOM atmospheric defense resources (interceptors, warning radars, and associated bases and personnel) were transferred to Tactical Air Command, being placed under Air Defense, Tactical Air Command (ADTAC). which was established compatible to a Numbered Air Force under TAC.  With this move many Air National Guard units that had an air defense mission also came under the control of TAC.  ADTAC was headquartered at North American Aerospace Defense Command, Ent AFB Colorado. In essence, Tactical Air Command became the old Continental Air Command.  On the same date, electronic assets went to the Air Force Communications Service (AFCS).


 * On 1 December 1979 missile warning and space surveillance assets were transferred to Strategic Air Command. On the same date the Aerospace Defense Center, a Direct Reporting Unit, was established from the remnants of ADCOM headquarters

ADCOM, as a specified command, continued as the United States component of NORAD, but the major air command was inactivated on 31 March 1980. The unit designation of the MAJCOM reverted to the control of the Department of the Air Force.

Major Events Time line

 * 27 March 1946 : The United States Army Air Force activates the Air Defense Command at Mitchel Field (later, Mitchel Air Force Base), New York
 * 1 December 1948 : The United States Air Force establishes the Continental Air Command (ConAC) over both the Air Defense Command and Tactical Air Command
 * 27 June 1950 : United States air defense systems begins 24-hour operations two days after the start of the Korean War
 * 1 July 1950 : Air Defense Command inactivated because the Continental Air Command gradually assumed full charge of United States air defense
 * 1 January 1951 : Air Defense Command re-established, again at Mitchel Field
 * 8 January 1951 : Air Defense Command headquarters moves from Mitchel Field to Ent Air Force Base, Colorado
 * 14 July 1952 : Air Defense Command begins 24-hour Ground Observer Corps operations
 * 1 October 1953 : The 4701st Airborne Early Warning and Control Squadron, the first AEW&C system, was activated at McClellan AFB, California.
 * 1 September 1954 : The Continental Air Defense Command (CONAD) is established at Ent Air Force Base as a joint-service force, taking control of Air Force Air Defense Command forces, Army Anti-Aircraft Command forces, and Naval air defense forces (NAVFORCONAD)
 * 15 April 1957 : Air Defense Command assigned operational control of the DEW Line and all atmospheric defense units of the inactivated Northeast Air Command.
 * 12 September 1957 : The North American Air Defense Command is established at Ent Air Force Base as an international organization, taking operational control of Canadian Air Defense Command air defense units and United States Continental Air Defense Command air defense units
 * 1 December 1958 :SAGE Combat Center No 1 at Hancock Field, New York (26th Air Division) became operational
 * 1 January 1959: The first BOMARC squadron, the 46th Air Defense Missile Squadron was activated at McGuire AFB, New Jersey.
 * 31 July 1959 : The Ground Observer Corps, active since July 1952, is abolished because of improvements in radar technology


 * 1 October 1960 : BMEWS Site I, at Thule AB, Greenland, reached initial operational capability; the first Ballistic Missile Early Warning System
 * 1 February 1961 : The 1st Aerospace Surveillance and Control Squadron established at Ent AFB, Colorado by Air Defense Command to operate the SPADATS Center. This marks the beginning of Air Defense Command's aerospace defense operations.
 * 1 July 1962 : Control of Air Forces Iceland transferred from Military Air Transport Service to Air Defense Command.
 * 3 September 1965 : Space Defense Center in Colorado Springs, Colorado activated
 * 15 January 1968 : Air Defense Command is redesignated as Aerospace Defense Command (ADCOM)
 * 31 October 1972 : Final BOMARC unit inactivated at Langley AFB, Virginia; BOMARC interceptor activity ended.
 * 1 July 1973 : Continental Air Defense Command and Aerospace Defense Command headquarters begins consolidation and streamlining
 * 4 February 1974 : The Department of Defense announces plans for cutbacks in air defense forces showing increasing emphasis on ballistic missile attack warning and decreasing emphasis on bomber defense
 * 30 June 1974 : Continental Air Defense Command dis-established
 * 1 July 1975 : Aerospace Defense Command designated a "Specified Command" taking over Continental Air Defense Command roles and responsibilities
 * 1 October 1975 : Alaskan ADCOM Region established, Aerospace Defense Command assumes control of missile warning and space surveillance forces of Alaskan Air Command
 * 1 October 1979 : Transfer of ADCOM atmospheric defense resources (interceptors and warning radars) to Tactical Air Command (TAC); Air Defense, Tactical Air Command (ADTAC) established as a Numbered Air Force equivalent under Tactical Air Command
 * 31 March 1980: Aerospace Defense Command inactivated at Colorado Springs, Colorado.
 * 1 October 1985 :ADTAC redesignated 1st Air Force, with US-Only ADCOM responsibilities under CONAD (COMTAC).

Lineage

 * Established as Air Defense Command on 21 March 1946
 * Activated as a major command on 27 March 1946
 * Became a subordinate operational command of Continental Air Command on 1 December 1948
 * Discontinued on 1 July 1950


 * Reestablished as a major command, and organized, on 1 January 1951
 * Redesignated Aerospace Defense Command on 15 January 1968
 * Inactivated on 31 March 1980.

Stations

 * Mitchel Field (Later AFB), New York, 21 March 1946
 * Ent AFB, Colorado, 1 January 1951 – 20 April 1966
 * Cheyenne Mountain, Colorado, 20 April 1966 – 31 March 1980

Air Defense Forces

 * Central Air Defense Force (CADF)
 * Activated on 1 March 1951 at Kansas City, Missouri
 * Moved to Grandview AFB, 10 March 1954
 * Station re-designated Richards-Gebaur AFB, 27 April 1952
 * Inactivated, 1 January 1960


 * Eastern Air Defense Force (CADF)
 * Activated by Continental Air Command on 1 September 1949 at Mitchel AFB, New York
 * Moved to Stewart AFB and assigned to Air Defense Command on 1 January 1951
 * Inactivated, 1 January 1960


 * Western Air Defense Force (WADF)
 * Activated by Continental Air Command on 1 September 1949 at Hamilton AFB, California
 * Re-assigned to Air Defense Command, 1 January 1951
 * Inactivated, 1 July 1960

Air Forces

 * First Air Force
 * Assigned to Air Defense Command, 27 March 1946 at Mitchel Field, New York
 * Moved to Fort Slocum, New York, 3 June 1946
 * Re-assigned to Continental Air Command, 1 December 1948
 * Re-assigned to Air Defense Command, 1 April 1966
 * Inactivated, 31 December 1969


 * Second Air Force
 * Re-activated on 6 June 1946 at Fort Crook, Nebraska
 * Assigned to Air Defense Command
 * Inactivated, 1 July 1948


 * Fourth Air Force
 * Assigned to Air Defense Command, 21 March 1946 at March Field, California
 * Moved to Hamilton Field, California on 19 June 1946
 * Re-assigned to Continental Air Command, 1 December 1948
 * Discontinued, 1 September 1960
 * Re-activated 1 April 1966 and assigned to Air Defense Command
 * Inactivated, 30 September 1969


 * Tenth Air Force, 21 March 1946 – 1 December 1948; 20 January 1966 – 8 October 1976
 * Re-activated 27 May 1946 at Brooks Field, Texas
 * Assigned to Air Defense Command
 * Re-assigned to Continental Air Command, 1 December 1948
 * Inactivated, 1 September 1960
 * Re-activated 1 April 1966 and assigned to Air Defense Command
 * Assigned to Richards-Gebaur AFB
 * Inactivated, 30 September 1969


 * Eleventh Air Force*
 * Activated 13 June 1946 at Olmsted Field, Middletown, Pennsylvania
 * Assigned to Air Defense Command
 * Inactivated, 1 July 1948


 * Fourteenth Air Force, 21 March 1946 – 1 December 1948; 20 January 1966 – 8 October 1976
 * Re-activated 24 May 1945 at Orlando Air Base, Florida
 * Assigned to Air Defense Command
 * Re-assigned to Continental Air Command, 1 December 1948
 * Inactivated, 1 September 1960
 * Re-activated 1 April 1966 and assigned to Air Defense Command
 * Assigned to Gunter AFB, Alabama
 * Re-designated Fourteenth Aerospace Force, 1 July 1968
 * Moved to Ent AFB, Colorado
 * Inactivated, 1 October 1976


 * Air Forces Iceland
 * Assigned to Air Defense Command from Military Air Transport Service, 1 July 1962
 * Stationed at Keflavik Airport, Iceland
 * Assigned to 64th Air Division
 * Transferred to: 26th Air Division, 1 July 1963
 * Transferred to: Goose Air Defense Sector, 4 September 1963
 * Transferred to: 37th Air Division, 1 April 1966
 * Transferred to: 21st Air Division, 31 December 1969
 * Re-assigned to Tactical Air Command, 1 October 1979

.Note: Assigned to Olmsted AFB, Pennsylvania, but never equipped or manned. Not to be confused with Eleventh Air Force, which was assigned to Alaskan Air Command

Regions

 * Alaskan ADCOM Region
 * Designated and activated at Elmendorf AFB, Alaska, 1 October 1975
 * Missile warning and space surveillence forces reassigned to Strategic Air Command, 1 December 1979
 * Re-designated as Alaska NORAD Region (ANR), 14 June 1983
 * Operational atmospheric defense units under operational control of Eleventh Air Force


 * 20th ADCOM Region
 * Designated and activated at Fort Lee AFS, Virginia, 8 December 1978
 * Supplementary ADCOM designation of 20th Air Division


 * 21st ADCOM Region
 * Designated and activated at Hancock AFS, New York, 8 December 1978
 * Supplementary ADCOM designation of 21st Air Division


 * 23d ADCOM Region
 * Designated and activated at Duluth AFS, Minnesota, 8 December 1978
 * Supplementary ADCOM designation of 23d Air Division


 * 24th ADCOM Region
 * Designated and activated at Malmstrom AFB, Montana, 8 December 1978
 * Supplementary ADCOM designation of 24th Air Division


 * 25th ADCOM Region
 * Designated and activated at McChord AFB, Washington, 8 December 1978
 * Supplementary ADCOM designation of 25th Air Division


 * 26th ADCOM Region
 * Designated and activated at Luke AFB, Arizona, 8 December 1978
 * Supplementary ADCOM designation of 26th Air Division

Air Divisions

 * 8th Air Division (Aircraft Early Warning & Control)
 * Activated 1 May 1954 at McClellan AFB, California
 * Assigned to Western Air Defense Force
 * Transferred to Air Defense Command, 1 May 1955
 * Inactivated, 1 July 1957


 * 9th Air Division (Defense)
 * Activated 8 October 1954 at Geiger Field, Washington
 * Assigned to Western Air Defense Force
 * Inactivated, 15 August 1958
 * Reactivated on 15 July 1961 as 9th Aerospace Air Division at Ent AFB, Colorado
 * Assigned to Air Defense Command
 * Discontinued, 1 July 1968


 * 20th Air Division
 * Activated on 8 October 1955 at Grandview AFB, Missouri
 * Assigned to Central Air Defense Force
 * Station re-designated as Richards-Gebaur AFB, 27 April 1957
 * Inactivated 1 January 1960
 * Re-activated on 1 April 1966 at Truax Field, Wisconsin
 * Assigned to Tenth Air Force
 * Discontinued 31 December 1967
 * Re-activated on 19 November 1969 at Fort Lee AFS, Virginia
 * Assigned to Air Defense Command
 * Re-assigned to Tactical Air Command, 1 October 1979


 * 21st Air Division
 * Activated 20 January 1966
 * Organized at McGuire AFB, New Jersey 1 April 1966
 * Assigned to First Air Force
 * Discontinued and inactivated 31 December 1967
 * Re-activated on 19 November 1969 at Hancock AFS, New York
 * Assigned to Air Defense Command
 * Re-assigned to Tactical Air Command, 1 October 1979


 * 23d Air Division
 * Activated 19 November 1969 at Duluth AFS, Minnesota
 * Assigned to First Air Force
 * Re-assigned to Air Defense Command on 1 December 1969
 * Re-assigned to Tactical Air Command, 1 October 1979


 * 24th Air Division
 * Activated 19 November 1969 at Malmstrom AFB, Montana
 * Assigned to Tenth Air Force
 * Re-assigned to Air Defense Command on 1 December 1969
 * Re-assigned to Tactical Air Command, 1 October 1979


 * 25th Air Division
 * Activated 25 October 1948 as 25th Air Division (Defense) at Silver Lake, Washington
 * Assigned to Fourth Air Force
 * Re-assigned to Western Air Defense Force, 1 February 1950
 * Moved to McChord AFB, 15 September 1951
 * Re-designated 25th Air Division (SAGE), 1 March 1959
 * Re-assigned to Air Defense Command on 1 July 1960
 * Re-assigned to Fourth Air Force, 1 April 1966
 * Re-assigned to Tenth Air Force, 1 April 1966
 * Re-assigned to Aerospace Defense Command, 1 December 1969
 * Re-assigned to Tactical Air Command, 1 October 1979


 * 26th Air Division
 * Activated 16 November 1948 at Mitchel AFB, New York
 * Assigned to First Air Force
 * Moved to Roslyn AFS, New York 18 April 1949
 * Re-designated 26th Air Division (Defense), 20 June 1949
 * Re-assigned to Eastern Air Defense Force, 1 September 1950
 * Re-designated 26th Air Division (SAGE), 8 August 1958 and moved to Syracuse AFS, New York
 * Transferred to Air Defense Command on 1 August 1959
 * Moved to Stewart AFB, New York, 15 June 1964
 * Re-designated 26th Air Division, 20 January 1966 and moved to Adair AFS, Oregon
 * Inactivated, 30 September 1969
 * Re-activated 19 November 1969 at Luke AFB, Arizona
 * Re-assigned to Tactical Air Command, 1 October 1979


 * 27th Air Division
 * Activated as 27th Air Division (Defense) on 20 November 1950 at Norton AFB, California
 * Assigned to Western Air Defense Force
 * Inactivated, 1 October 1959
 * Organized as 27th Air Division on 1 April 1966 at Luke AFB, Arizona
 * Assigned to Fourth Air Force
 * Re-assigned to Tenth Air Force on 15 September 1969
 * Inactivated 19 November 1969


 * 28th Air Division
 * Assigned to Western Air Defense Force on 1 January 1951 as 28th Air Division (Defense)
 * Assigned to Hamilton AFB, California
 * Re-designated as 28th Air Division (SAGE) and transferred to Air Defense Command, 1 July 1960
 * Re-designated 28th Air Division,, 1 April 1966
 * Moved to Malmstrom AFB, Montana and assigned to Tenth Air Force, 1 April 1966
 * Inactivated 19 November 1969


 * 29th Air Division
 * Activated 1 March 1951 at Great Falls AFB, Montana
 * Assigned to Western Air Defense Force
 * Transferred to Central Air Defense Force, 16 February 1953
 * Great Falls AFB re-designated Malmstrom AFB, Montana, 1 October 1955
 * Re-designated as 29th Air Division (SAGE) and transferred to Air Defense Command, 1 July 1960
 * Moved to Richards-Gebaur AFB, Missouri, 1 July 1961
 * Re-designated 29th Air Division, 1 April 1966
 * Moved to Duluth AFS, Minnesota, and assigned to Tenth Air Force, 1 April 1966
 * Re-assigned to First Air Force on 15 September 1969
 * Inactivated 19 November 1969


 * 30th Air Division,
 * Activated on 16 December 1949 as 30th Air Division (Defense) at Selfridge AFB, Michigan
 * Assigned to Air Defense Command
 * Moved to Willow Run AFS, Michigan on 1 April 1952
 * Assigned to Eastern Air Defense Force, 1 April 1952
 * Re-designated 30th Air Division (SAGE), 1 April 1959 and moved to Truax Field, Wisconsin
 * Re-assigned to Air Defense Command on 1 July 1959
 * Re-designated 30th Air Division and moved to Sioux City AFS, Iowa (w/o p/e), 1 April 1966
 * Re-assigned to Tenth Air Force, 1 April 1966
 * Discontinued 18 September 1968


 * 31st Air Division
 * Activated on 8 October 1950 as 31st Air Division (Defense) at Selfridge AFB, Michigan
 * Assigned to Eastern Air Defense Force
 * Re-assigned to Air Defense Command on 1 January 1951
 * Moved to Snelling AFS, Minnesota on 18 December 1950
 * Re-assigned to Central Air Defense Force, 20 May 1950
 * Inactivated 1 January 1960
 * Organized at Oklahoma City AFS, Oklahoma on 1 April 1966
 * Assigned to Fourteenth Air Force, 1 April 1966
 * Re-assigned to Tenth Air Force on 1 July 1968
 * Inactivated on 31 December 1969


 * 32d Air Division
 * Assigned on 1 January 1951 to Eastern Air Defense Force at Stewart AFB, New York
 * Moved to Syracuse AFS, New York, 15 February 1952
 * Inactivated on 15 August 1958
 * Reactivated on 15 November 1958 as 32d Air Division (SAGE) at Dobbins AFB, Georgia
 * Assigned to Eastern Air Defense Force
 * Re-assigned to Air Defense Command, 1 August 1959
 * Moved to Oklahoma City AFS, Oklahoma, 1 August 1961
 * Discontinued 4 September 1963
 * Organized at Gunter AFB, Alabama, 1 April 1966
 * Assigned to Fourteenth Air Force
 * Re-assigned to Tenth Air Force, 1 July 1968
 * Inactivated 31 December 1969


 * 33d Air Division
 * Activated on 19 March 1951 as 33d Air Division (Defense) at Tinker AFB, Oklahoma
 * Assigned to Eastern Air Defense Force
 * Re-assigned to Central Air Defense Force, 20 May 1951
 * Moved to Oklahoma City AFS, Oklahoma, 1 July 1956
 * Re-designated 33d Air Division (SAGE) and moved to Richards-Gebaur AFB, Missouri, 1 January 1960
 * Re-assigned to Air Defense Command
 * Discontinued 1 July 1961
 * Organized on 1 April 1966 as 33d Air Division at Fort Lee AFS, Virginia
 * Assigned to First Air Force
 * Inactivated 19 November 1969


 * 34th Air Division
 * Activated on 5 January 1951 at Kirtland AFB, New Mexico
 * Assigned to Western Air Defense Force
 * Re-assigned to Central Air Defense Force 15 February 1953
 * Inactivated 1 January 1960
 * Organized at Custer AFS, Michigan, 1 April 1966
 * Assigned to First Air Force
 * Inactivated 31 December 1969


 * 35th Air Division
 * Activated on 1 July 1951 at Kansas City, Missouri
 * Assigned to Central Air Defense Force
 * Moved to Dobbins AFB, Georgia, 1 September 1951
 * Re-assigned to Eastern Air Defense Force, 10 April 1955
 * Inactivated 15 November 1958
 * Organized on 1 April 1966 at Syracuse AFS, New York
 * Inactivated 19 November 1968


 * 36th Air Division
 * Activated 1 April 1966 at Topsham AFS, Maine
 * Assigned to First Air Force
 * Inactivated 30 September 1969


 * 37th Air Division
 * Activated on 10 October 1951 at Lockborne AFB, Ohio under Strategic Air Command
 * Moved to Truax Field, Wisconsin 8 September 1955 and transferred to Air Defense Command
 * Assigned to Eastern Air Defense Force
 * Inactivated 1 April 1959
 * Organized on 1 April 1966 at Goose AFB, Labrador, Canada
 * Assigned to First Air Force
 * Re-assigned to Aerospace Defense Command, 1 December 1969
 * Inactivated 10 June 1970


 * 58th Air Division (Defense)
 * Activated 8 September 1955 at Wright-Patterson AFB, Ohio
 * Assigned to Eastern Air Defense Force
 * Inactivated 1 February 1959


 * 64th Air Division
 * Transferred on 1 April 1957 to Air Defense Command from Northeast Air Command
 * Assigned to Pepperrell AFB, Newfoundland
 * Moved to Stewart AFB, New York, 26 May 1960
 * Discontinued, 1 July 1963


 * 73d Air Division
 * Activated 1 July 1957 as 73d Air Division (Weapons) at Tyndall AFB, Florida
 * Assigned to Air Defense Command
 * Re-designated 73d Air Division, 1 March 1963
 * Discontinued 1 April 1966


 * 85th Air Division
 * Activated 8 September 1955 at Andrews AFB, Maryland
 * Assigned to Eastern Air Defense Force
 * Inactivated 1 September 1958

Air Defense Sectors

 * Albuquerque Air Defense Sector
 * Activated on 1 January 1960 at Kirtland AFB, New Mexico
 * Assigned to 33d Air Division
 * Discontinued 1 November 1960


 * Bangor Air Defense Sector
 * Activated on 8 January 1957 at Topsham AFS, Maine
 * Assigned to 32d Air Division
 * Re-assigned to 26th Air Division, 15 August 1958
 * Discontinued 1 April 1966


 * Boston Air Defense Sector
 * Formed by re-designation of 4622d Air Defense Wing (SAGE), 8 January 1957
 * Activated at Stewart AFB, New York
 * Assigned to 26th Air Division
 * Moved to Syracuse AFS, New York 1 April 1966
 * Discontinued 1 April 1966


 * Chicago Air Defense Sector
 * Formed by re-designation of 4628th Air Defense Wing, 8 March 1957
 * Activated at Truax Field, Wisconsin
 * Assigned to 37th Air Division
 * Re-assigned to 30th Air Division, 1 April 1959
 * Discontinued 1 April 1966


 * Detroit Air Defense Sector
 * Formed by re-designation of 4627th Air Defense Wing, 8 January 1957
 * Activated at Custer AFS, Michigan
 * Assigned to 30th Air Division
 * Re-assigned to 26th Air Division, 4 September 1963
 * Discontinued 1 April 1966


 * Duluth Air Defense Sector
 * Activated 8 October 1957 at Duluth AFS, Minnesota
 * Assigned to 37th Air Division (EADF)
 * Re-assigned to 31st Air Division (CADF), 20 December 1957
 * Re-assigned to 37th Air Division, 1 January 1959
 * Re-assigned to 30th Air Division, 1 April 1959
 * Discontinued 1 April 1966


 * Goose Air Defense Sector
 * Activated on 1 April 1960 at Goose AFB, Labrador, Canada
 * Assigned to 64th Air Division
 * Re-assigned to 26th Air Division (SAGE), 1 July 1963
 * Discontinued on 1 April 1966


 * Grand Forks Air Defense Sector
 * Activated on 8 December 1957 at Grand Forks AFB, North Dakota
 * Assigned to 31st Air Division
 * Re-assigned to 29th Air Division, 1 January 1959
 * Discontinued on 1 December 1963


 * Great Falls Air Defense Sector
 * Activated on 1 March 1959 at Malmstrom AFB, Montana
 * Assigned to 29th Air Division
 * Discontinued on 1 April 1966


 * Kansas City Air Defense Sector
 * Activated on 1 January 1960 at Richards-Gebaur AFB, Missouri
 * Assigned to 33d Air Division
 * Re-assigned to 29th Air Division, 1 July 1961
 * Discontinued 1 January 1962


 * Los Angeles Air Defense Sector
 * Activated on 15 February 1959 at Norton AFB, California
 * Assigned to 27th Air Division
 * Re-assigned to Western Air Defense Force, 1 October 1959
 * Re-assigned to 28th Air Division, 1 July 1960
 * Re-assigned to Fourth Air Force, 1 April 1966
 * Discontinued 25 June 1966


 * Minot Air Defense Sector
 * Activated on 1 April 1959 at Minot AFB, North Dakota
 * Assigned to 29th Air Division
 * Discontinued 15 August 1963


 * Montgomery Air Defense Sector
 * Activated on 8 September 1957 at Gunter AFB, Alabama
 * Assigned to 35th Air Division
 * Re-assigned to 32d Air Division, 15 November 1958
 * Re-assigned to 26th Air Division (SAGE), 1 July 1963
 * Assigned to Air Defense Command, 1 October 1964
 * Discontinued 1 April 1966


 * New York Air Defense Sector
 * Formed through re-designation of 4621st Air Defense Wing (SAGE), 8 January 1957
 * Assigned to McGuire AFB, New Jersey
 * Assigned to 26th Air Division
 * Discontinued 1 April 1966


 * Oklahoma City Air Defense Sector
 * Activated on 1 January 1960 at Oklahoma City AFS, Oklahoma
 * Assigned to 33d Air Division
 * Re-assigned to 32d Air Division, 1 July 1961
 * Discontinued 1 September 1961
 * Re-activated 25 June 1963 at Oklahoma City AFS
 * Assigned to 29th Air Division (SAGE)
 * Discontinued 1 April 1966


 * Phoenix Air Defense Sector
 * Activated on 15 June 1959 at Luke AFB, Arizona
 * Assigned to Western Air Defense Force
 * Re-assigned to 28th Air Division, 1 July 1960
 * Discontinued 1 April 1966


 * Portland Air Defense Sector
 * Activated on 1 September 1958 at Adair AFS, Oregon
 * Assigned to 25th Air Division
 * Discontinued 1 April 1966


 * Reno Air Defense Sector
 * Activated on 15 February 1959 at Stead AFB, Nevada
 * Assigned to 25th Air Division
 * Re-assigned to 28th Air Division, 1 July 1960
 * Re-assigned to Fourth Air Force, 1 April 1966
 * Discontinued 25 June 1966


 * San Francisco Air Defense Sector
 * Activated on 15 February 1959 at Beale AFB, California
 * Assigned to 28th Air Division
 * Discontinued 1 August 1963


 * Sault Sainte Marie Air Defense Sector
 * Activated on 8 November 1958 at K. I. Sawyer AFB, Michigan
 * Assigned to 37th Air Division
 * Re-assigned to 30th Air Division, 1 April 1959
 * Discontinued 15 December 1963


 * Seattle Air Defense Sector
 * Activated on 8 January 1958 at McChord AFB, Washington
 * Assigned to 25th Air Division
 * Discontinued 1 April 1966


 * Sioux City Air Defense Sector
 * Activated on 1 October 1959 at Sioux City AFS, Iowa
 * Assigned to 20th Air Division
 * Re-assigned to 33d Air Division, 1 January 1960
 * Re-assigned to 29th Air Division, 1 July 1961
 * Discontinued 1 April 1966


 * Spokane Air Defense Sector
 * Activated on 8 September 1958 at Larson AFB, Washington
 * Assigned to 25th Air Division
 * Discontinued 1 September 1963


 * Syracuse Air Defense Sector
 * Formed through re-designation of 4624th Air Defense Wing (SAGE), 8 January 1957
 * Activated at Syracuse AFS, New York
 * Assigned to 32d Air Division
 * Re-assigned to 25th Air Division, 15 August 1958
 * Discontinued 4 September 1963


 * Washington Air Defense Sector
 * Formed through re-designation of 4625th Air Defense Wing (SAGE), 8 January 1957
 * Activated at Fort Lee AFS, Virginia
 * Assigned to 85th Air Division
 * Re-assigned to 26th Air Division, 1 September 1958
 * Discontinued 1 April 1966

Centers

 * Aerospace Defense Center
 * Activated on 1 December 1979 at Colorado Springs, Colorado
 * Transferred to HQ, United States Air Force, 1 December 1979


 * Air Defense Weapons Center
 * Organized at Tyndall AFB, Florida, 31 October 1967
 * Assigned to Air Defense Command
 * Transferred to Tactical Air Command, 1 October 1979


 * Aerospace Defense Command Combat Operations Center (COC)
 * Designated and activated as NORAD Combat Operations Center, 21 April 1976
 * Assigned to Cheyenne Mountain Complex City, Colorado
 * Assigned to Aerospace Defense Command, 21 April 1976
 * Re-designated ADCOM CONIC, 30 June 1976
 * Transferred to Tactical Air Command, 1 October 1979