520th Air Defense Group
The 520th Air Defense Group was a United States Air Force organization that supported wartime bomber operations and later coordinated fighter-interceptor defenses over the Great Lakes region.
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Overview
The 520th Air Defense Group was a United States Air Force organization with two distinct periods of service. It originated during the final phase of the Second World War as the 520th Air Service Group, a specialized support formation created to sustain the 340th Bombardment Group in Italy. Unlike earlier Army Air Forces service groups, which could combine personnel from multiple Army branches and support more than one combat group, the newer air service group structure was composed of Air Corps personnel and was designed to support a single combat group. The 520th’s subordinate organizations provided the technical, supply, and base-support functions required by the 340th Bombardment Group. The wartime group included the 946th Air Engineering Squadron, which performed aircraft maintenance beyond the capability of the combat group; the 770th Air Materiel Squadron, which managed supply activities; and a Headquarters & Base Services Squadron, which handled general installation and administrative support. Activated in Italy in December 1944, the organization operated first from Cervioni and subsequently moved through Rimini and Naples as Allied operations progressed. It returned to the United States in 1945, passing through Camp Patrick Henry, Virginia, Seymour Johnson Field, North Carolina, and Columbia Army Air Base, South Carolina. It was inactivated in late 1945 and formally disbanded in 1948. The organization was revived in a substantially different role during the early Cold War. Reconstituted and redesignated as the 520th Air Defense Group, it was activated at Truax Field, Wisconsin, on 16 February 1953. Its mission was to provide command and support for a dispersed fighter-interceptor force responsible for air defense in the Great Lakes area. The group was assigned the 432d and 433d Fighter-Interceptor Squadrons, which had previously reported directly to the 31st Air Division. It also became the United States Air Force host organization at Truax Field, replacing the 78th Air Base Squadron. The group’s structure combined operational interceptor squadrons with medical, aircraft-maintenance, and administrative support units. Its aircraft represented the changing technology of the period: the 432d Fighter-Interceptor Squadron operated radar-equipped North American F-86 Sabres, while the 433d Fighter-Interceptor Squadron flew Northrop F-89 Scorpions fitted with airborne-intercept radar. The group was also associated with the Lockheed F-94 Starfire. In March 1953, the 432d squadron transitioned to a later F-86 model equipped with radar and Mighty Mouse air-to-air rockets, reflecting the growing emphasis on rapid interception of hostile aircraft in the postwar air-defense system. The group’s composition changed in 1954. The 433d Fighter-Interceptor Squadron transferred to Alaska in July, and the 456th Fighter-Interceptor Squadron was activated at Truax Field the following month as its replacement. The 456th also operated Sabres. In 1955, Air Defense Command implemented Project Arrow, a reorganization intended to restore historically distinguished Second World War fighter units to the active force. Under that program, the 520th Air Defense Group was inactivated on 18 August 1955, and its mission, equipment, and personnel were transferred to the 327th Fighter Group (Air Defense). The 520th was disbanded again in 1984. It therefore did not survive as a continuing operational unit, commercial brand, or independent institution, but its record illustrates the transition from wartime logistical support formations to integrated Cold War fighter-interceptor command structures.
History
The 520th Air Defense Group traces its institutional lineage to the 520th Air Service Group, activated on 27 December 1944 during the reorganization of Army Air Forces support units. The new air service group model was intended to provide dedicated support to a single combat group using Air Corps personnel. The 520th was assigned to support the 340th Bombardment Group in Italy during the closing months of the Second World War. Its 946th Air Engineering Squadron handled higher-level aircraft maintenance, the 770th Air Materiel Squadron managed supplies, and the Headquarters & Base Services Squadron supplied general administrative and installation services. The organization was stationed at Cervioni, Italy, before moving to Rimini and Naples as the war ended. It then returned to the United States through Camp Patrick Henry, Virginia, Seymour Johnson Field, North Carolina, and Columbia Army Air Base, South Carolina. The wartime formation was inactivated around 7 November 1945 and disbanded on 8 October 1948. The United States Air Force later revived the lineage for a Cold War air-defense mission. The unit was reconstituted and redesignated as the 520th Air Defense Group on 21 January 1953 and activated at Truax Field, Wisconsin, on 16 February. It was assigned to the 4706th Defense Wing, later the 4706th Air Defense Wing, and served as the headquarters for fighter-interceptor and support elements defending the Great Lakes area. At Truax Field, the group assumed responsibility for the 432d and 433d Fighter-Interceptor Squadrons, which had previously been assigned directly to the 31st Air Division. It also replaced the 78th Air Base Squadron as the Air Force host unit at the field. Medical, maintenance, supply, and administrative squadrons allowed the group to combine operational command with base support. The 432d operated North American F-86 Sabres, including a radar-equipped and Mighty Mouse rocket-armed variant introduced in 1953. The 433d operated Northrop F-89C Scorpions with airborne-intercept radar and was also associated with the Lockheed F-94 Starfire during the period. The group’s subordinate structure changed as the wider air-defense network was reorganized. The 433d Fighter-Interceptor Squadron moved to Alaska in July 1954. The 456th Fighter-Interceptor Squadron was activated at Truax Field in August 1954 to replace it and was likewise equipped with Sabres. Air Defense Command ended the group’s second period of service through Project Arrow, a program intended to return fighter units with distinguished records in the two world wars to active status. On 18 August 1955, the 520th Air Defense Group was inactivated and its mission, equipment, and personnel were transferred to the 327th Fighter Group (Air Defense). The 520th was formally disbanded on 27 September 1984. Its lineage consequently reflects two different organizational functions: wartime bomber-group support and early Cold War command of a regional interceptor-defense system.
- 1984
Final disbandment
[1]The lineage was disbanded for a second time on 27 September 1984.
- 1955
Inactivation under Project Arrow
[1]The group was inactivated on 18 August when Air Defense Command transferred its mission, equipment, and personnel to the 327th Fighter Group (Air Defense).
- 1954
Replacement of the 433d Fighter-Interceptor Squadron
[1]The 433d Fighter-Interceptor Squadron moved to Alaska in July, and the 456th Fighter-Interceptor Squadron was activated at Truax Field in August as its replacement.
- 1953
Reconstitution as an air-defense group
[1]The lineage was reconstituted and redesignated on 21 January, then activated at Truax Field on 16 February to command and support fighter-interceptor defenses in the Great Lakes area.
- 1953
F-86 modernization
[1]The 432d Fighter-Interceptor Squadron converted to a radar-equipped, Mighty Mouse rocket-armed F-86 variant in March.
- 1948
First formal disbandment
[1]The wartime organization was disbanded on 8 October 1948.
- 1945
Return to the United States and wartime inactivation
[1]After the end of combat operations in Europe, the group returned through several United States bases and was inactivated around 7 November 1945.
- 1944
Activation as the 520th Air Service Group
[1]The organization was activated on 27 December 1944 in Italy to provide dedicated engineering, supply, and base services to the 340th Bombardment Group.
Products and positioning
A military support and air-defense organization rather than a commercial brand. Its wartime identity centered on specialized logistical support for a bomber group; its Cold War identity centered on command and sustainment of fighter-interceptor squadrons assigned to the defense of the Great Lakes region.
Fighter-interceptor aircraft · 1953
North American F-86 Sabre
The 432d Fighter-Interceptor Squadron operated F-86 Sabres while assigned to the group. In 1953 it converted to a later radar-equipped model armed with Mighty Mouse rockets, giving the squadron a more specialized capability for the Cold War interception mission. The 456th Fighter-Interceptor Squadron, which replaced the 433d at Truax Field in 1954, also operated Sabres.
All-weather interceptor aircraft · 1953
Northrop F-89C Scorpion
The 433d Fighter-Interceptor Squadron operated F-89C Scorpions during the group’s early Cold War activation. The aircraft’s airborne-intercept radar supported the group’s all-weather defense mission before the squadron transferred to Alaska in July 1954.
Jet interceptor aircraft · 1953
Lockheed F-94 Starfire
The Lockheed F-94 Starfire is identified among the aircraft associated with the group during its 1953 air-defense service. The available reference does not specify the precise squadron assignment or duration of operation.
Brand decisions
1955
Transfer of the air-defense mission under Project ArrowStrategyBackground
Air Defense Command used Project Arrow to restore historically distinguished fighter units from the two world wars to the active list and to replace air-defense groups commanding fighter squadrons with fighter groups.
Action taken
The 520th Air Defense Group was inactivated, and its mission, equipment, and personnel were transferred to the 327th Fighter Group (Air Defense) on 18 August 1955.
Aftermath
The 520th ceased operations and was later disbanded in 1984, while the 327th Fighter Group assumed the Truax Field air-defense role.
Sources1 sources
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