517th Air Defense Group
The 517th Air Defense Group was a United States Air Force organization that provided combat-support and air-defense coordination during the final months of World War II and the early Cold War.
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Overview
The 517th Air Defense Group was a United States Air Force organization with two distinct periods of service. It originated during the final months of World War II as the 517th Air Service Group, a support formation created to provide engineering, materiel, base-service, and administrative assistance to Army Air Forces combat units in Italy. The group was activated on 13 January 1945 at Caserta and was associated with operations at Pantanella Airfield. Its organizational structure reflected a wartime effort to separate specialized Air Corps support functions from broader Army service formations. The 943rd Air Engineering Squadron handled maintenance beyond the capability of the supported combat group, while the 767th Air Materiel Squadron managed supply responsibilities and the Headquarters and Base Services Squadron handled additional installation support. Sources differ over whether its principal supported combat formation was the 464th or 465th Bombardment Group, although the 517th and 518th Air Service Groups jointly supported bombardment units at Pantanella. As the European war ended, the 517th moved to the Caribbean. At Waller Field, Trinidad, it supported combat units and personnel being redeployed from Europe to the United States. That first incarnation was inactivated on 31 July 1945 and later disbanded in 1948. The organization was reconstituted and redesignated as the 517th Air Defense Group in January 1953, then activated at Ethan Allen Air Force Base, Vermont, on 16 February 1953. In this Cold War form, it served under the 4711th Defense Wing, later the 4711th Air Defense Wing, and was responsible for coordinating the air-defense mission in upper New England. The group also became the United States Air Force host organization at Ethan Allen, replacing the 75th Air Base Squadron. Its structure combined an operational fighter-interceptor squadron with medical, maintenance, materiel, and base-support elements. The operational component was the 37th Fighter-Interceptor Squadron, which had already been stationed at Ethan Allen. It initially operated F-51D Mustangs and converted in June 1953 to radar-equipped North American F-86D Sabres armed with Mighty Mouse air-to-air rockets. The group’s support structure included the 517th Air Base Squadron, 517th Materiel Squadron, and 517th Medical Squadron, later identified as the 517th United States Air Force Infirmary. The 517th Air Defense Group was inactivated on 18 August 1955. Its mission, equipment, and personnel were transferred to the 14th Fighter Group (Air Defense) under Air Defense Command’s Project Arrow. Project Arrow sought to place fighter units with notable records from the two world wars back on the active list, replacing some postwar air-defense groups with historically distinguished fighter groups. The 517th was subsequently disbanded on 27 September 1984. It was therefore not a commercial brand or continuing operating company, but a historical military unit whose identity was tied to organizational lineage, air-defense command, and wartime support functions.
History
The 517th Air Defense Group traces its lineage to the 517th Air Service Group, which was activated on 13 January 1945 at Caserta, Italy. It was established during a reorganization of Army Air Forces support structures near the end of World War II. The new air service groups were intended to concentrate specialized Air Corps functions and support individual combat groups more directly than earlier formations that combined personnel from multiple Army branches. The group was associated with the 943rd Air Engineering Squadron, the 767th Air Materiel Squadron, and a headquarters and base-services element. Engineering personnel performed maintenance beyond the capacity of the supported combat formation, the materiel squadron managed supplies, and the headquarters element provided installation and administrative services. The 517th operated in the Pantanella Airfield area and worked alongside the 518th Air Service Group in supporting bombardment units. Historical accounts are not completely consistent about whether the 517th’s designated principal customer was the 464th or 465th Bombardment Group, but its general role as a combat-support formation is clear. Following the end of major combat operations in Europe, the organization moved to Waller Field, Trinidad, under the Caribbean Wing of Air Transport Command. There it supported combat units and personnel being redeployed from Europe to the United States. The wartime organization was inactivated on 31 July 1945 and disbanded in 1948. On 21 January 1953, the lineage was reconstituted and redesignated as the 517th Air Defense Group. It was activated on 16 February 1953 at Ethan Allen Air Force Base in Vermont and assigned to the 4711th Defense Wing, later redesignated the 4711th Air Defense Wing. The Cold War group was responsible for air-defense activities in upper New England and replaced the 75th Air Base Squadron as the Air Force host organization at Ethan Allen. Its operational element was the 37th Fighter-Interceptor Squadron, which had already been based at Ethan Allen. The squadron flew F-51D Mustangs at the beginning of the group’s second period of service. In June 1953, it transitioned to North American F-86D Sabres equipped with airborne interception radar and Mighty Mouse unguided rockets. The group’s supporting units included the 517th Air Base Squadron, 517th Materiel Squadron, and 517th Medical Squadron, the latter later being known as the 517th United States Air Force Infirmary. The group was inactivated on 18 August 1955. This change formed part of Air Defense Command’s Project Arrow, which sought to revive fighter organizations with distinguished service records from the two world wars. The 14th Fighter Group (Air Defense) took over the 517th’s mission, equipment, and personnel. Although the group itself no longer operated, its lineage remained on the Air Force rolls until it was disbanded on 27 September 1984.
- 1984
Disbanded
[1]The organization was finally disbanded on 27 September.
- 1955
Inactivated and replaced by the 14th Fighter Group
[1]The group was inactivated on 18 August after Project Arrow transferred its mission, equipment, and personnel to the 14th Fighter Group (Air Defense).
- 1953
Reconstituted as an air-defense group
[1]The lineage was redesignated the 517th Air Defense Group and activated at Ethan Allen Air Force Base on 16 February.
- 1953
37th Fighter-Interceptor Squadron upgraded
[1]The operational squadron transitioned from F-51D Mustangs to radar-equipped F-86D Sabres.
- 1948
Wartime lineage disbanded
[1]The original 517th Air Service Group was formally disbanded after its 1945 inactivation.
- 1945
Activated as the 517th Air Service Group
[1]The organization was activated on 13 January at Caserta, Italy, as a specialized Army Air Forces support group.
- 1945
Moved to Pantanella Airfield
[1]The group supported bombardment formations in Italy through engineering, supply, and base-service units.
- 1945
Redeployed to Trinidad
[1]At Waller Field, the group supported the return of combat units from Europe to the United States.
Products and positioning
A United States Air Force support and air-defense organization rather than a commercial brand. Its Cold War role centered on integrating a fighter-interceptor squadron with the maintenance, supply, medical, and administrative functions required for regional air defense.
Fighter aircraft · 1953
F-51D Mustang
The 37th Fighter-Interceptor Squadron operated F-51D Mustangs when the 517th Air Defense Group was activated in 1953. In the group’s air-defense structure, the aircraft represented the initial operational equipment before the squadron transitioned to jet-powered F-86D interceptors.
Radar-equipped interceptor aircraft · 1953
North American F-86D Sabre
Beginning in June 1953, the 37th Fighter-Interceptor Squadron flew F-86D Sabres equipped with airborne interception radar and Mighty Mouse rockets. The aircraft formed the principal operational component of the group’s Cold War air-defense mission in upper New England.
Military logistics and engineering services · 1945
Air Service Group support
During World War II, the 517th provided specialized support through engineering, materiel, headquarters, and base-service functions. These capabilities sustained bombardment formations in Italy and later supported redeployment operations in the Caribbean.
Brand decisions
1955
Replacement under Project ArrowStrategyBackground
Air Defense Command sought to restore fighter groups with distinguished records from the two world wars to the active list.
Action taken
The 517th Air Defense Group was inactivated and its mission, equipment, and personnel were transferred to the 14th Fighter Group (Air Defense).
Aftermath
The 14th Fighter Group assumed the relevant air-defense responsibilities at the end of the 517th’s active service.
1953
Transition from F-51D Mustangs to F-86D SabresGeneration changeBackground
The 37th Fighter-Interceptor Squadron initially operated piston-engine F-51D aircraft while assigned to the newly activated air-defense group.
Action taken
In June 1953, the squadron converted to radar-equipped F-86D interceptors armed with Mighty Mouse rockets.
Aftermath
The transition gave the group a jet interceptor capability for its upper-New England air-defense mission.
Recent events
- 1955
517th Air Defense Group inactivated under Project Arrow[1]
Other
Air Defense Command transferred the group’s mission, equipment, and personnel to the 14th Fighter Group (Air Defense), and the 517th was inactivated.
- 1953
517th Air Defense Group activated at Ethan Allen Air Force Base[1]
Other
The reconstituted organization assumed a regional air-defense and host-base support role in Vermont under the 4711th Defense Wing.
- 1953
37th Fighter-Interceptor Squadron converted to F-86D Sabres[1]
Product generation
The group’s operational squadron transitioned from F-51D Mustangs to radar-equipped F-86D interceptors armed with Mighty Mouse rockets.
- 1945
517th Air Service Group activated in Italy[1]
Other
The organization was activated as the 517th Air Service Group to provide engineering, supply, and base support for Army Air Forces combat formations in Italy.
- 1945
Group relocated to Trinidad for redeployment support[1]
Other
After the European war ended, the group moved to Waller Field, Trinidad, where it supported units returning from Europe to the United States.
Sources1 sources
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