20th Air Base Group
The 20th Air Base Group was a United States Army Air Forces support unit based at Nichols Field in the Philippines during the interwar period and the defense of the Philippines in World War II.
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Overview
The 20th Air Base Group was a United States Army Air Forces installation-support and aircraft-maintenance organization associated primarily with Nichols Field in the Philippines. It was not a commercial brand, but a military unit whose principal responsibilities included base administration, materiel support, aircraft maintenance, and related logistical services for flying units stationed in the Philippines. Its institutional lineage reached back to the 66th Aero Squadron, organized at Kelly Field, Texas, in April 1918 for service at the Eberts Field flying school during World War I. That predecessor was demobilized after the war, while a separately organized Philippine support organization developed into the group’s principal operational ancestor. In June 1921, Air Park No. 11 was organized in the Philippines. It moved from Clark Field to Nichols Field later that year and was redesignated the 66th Service Squadron in January 1923. The squadron provided second-level maintenance for aircraft associated with the 4th Composite Group. In 1936, the earlier 66th Aero Squadron lineage was consolidated with the postwar 66th Service Squadron. As the Air Corps reorganized its Philippine support structure, the 66th was combined with the Nichols Field station complement in May 1938 to form the Base Headquarters and 20th Air Base Squadron. Further redesignations followed as the organization expanded and its administrative and materiel functions were grouped together. The formal 20th Air Base Group emerged in 1940, when the Air Corps enlarged air base squadrons into groups and assigned aircraft-maintenance and administrative components to them. The group included an air base squadron and two materiel squadrons, with an aviation ordnance company attached during the period immediately before the Pacific War. It supported several flying organizations at Nichols Field, including observation and pursuit units, while also operating as part of the broader Far East Air Force structure. After Japan attacked the Philippines in December 1941, Nichols Field came under repeated air attack. The first concentrated attack on 10 December destroyed or disabled the observation aircraft based there. As American aircraft and headquarters elements withdrew toward Australia and Bataan, the group’s normal base-support role became increasingly difficult to sustain. Many of its personnel were used as ground troops as the defense of the Philippines contracted. The group ceased to function as an organized formation when the American resistance in the Philippines ended in 1942, although it remained on the Army Air Forces rolls during the war and was not formally inactivated until 2 April 1946. The 20th Air Base Group was disbanded in 1984. A separate postwar organization, the 20th Airdrome Group, was renamed the 20th Air Base Group in 1948 while assigned to the 20th Fighter Wing. That later unit subsequently became the 20th Mission Support Group and should be distinguished from the World War II-era group that is the subject of the canonical article. The group therefore represents a historical military lineage and support organization rather than an active commercial brand or present-day operating enterprise.
History
The unit’s earliest documented predecessor was the 66th Aero Squadron, organized on 26 April 1918 at Kelly Field, Texas. It soon moved to Eberts Field, Arkansas, where it supported the primary flying school. During the Air Service reorganization of 1918 it became Squadron A, Eberts Field, and was demobilized on 15 November 1918 after World War I. Its lineage was later consolidated with a separate Philippine maintenance organization bearing the same numerical designation. Air Park No. 11 was organized on 2 June 1921 at Clark Field in the Philippines and moved to Nichols Field, then known as Camp Nichols, by the end of that year. On 25 January 1923 it became the 66th Service Squadron. The organization provided second-level maintenance for aircraft of the 4th Composite Group and operated under the constraints of a small overseas garrison, including substantial shortages of officers during the early 1920s. In 1936 the Air Corps consolidated the World War I 66th Aero Squadron lineage with the Philippine 66th Service Squadron. The Air Corps subsequently expanded the support structure at Nichols Field. On 25 May 1938, the 66th Service Squadron was consolidated with the station complement to form the Base Headquarters and 20th Air Base Squadron. It underwent additional administrative redesignations in 1939 and 1940. On 1 September 1940 it became Headquarters and Headquarters Squadron, 20th Air Base Group (Reinforced), marking the formation’s transition into a larger organization with both administrative and technical support responsibilities. Its components included the 20th Air Base Squadron, later redesignated the 19th Air Base Squadron; the 1st Materiel Squadron, later the 27th Materiel Squadron; and the 2d Materiel Squadron, later the 28th Materiel Squadron. An aviation ordnance company was attached from approximately May 1941, and a weather detachment served with it for part of 1941. The group was assigned successively to the Primary Flying School at Eberts Field, the 1st Group (Composite), the Philippine Department, the Philippine Department Air Force, and ultimately the Far East Air Force and its successor service commands. Its main Philippine station was Nichols Field, where it supported observation and pursuit organizations, including the 2d Observation Squadron, 17th Pursuit Squadron, and 34th Pursuit Squadron, as well as the broader air-base system. The Pacific War transformed the group’s role. Japanese forces attacked Nichols Field soon after the United States entered the war. A concentrated attack on 10 December 1941 destroyed or rendered unusable the observation aircraft at the field. By 24 December, American bombers had been moved to Australia, and headquarters and most combat elements soon followed. Remaining American forces concentrated around Bataan, while the group’s personnel—originally trained and organized for maintenance, administration, and logistics—were increasingly employed as infantry. Organized resistance in the Philippines ended in 1942, and the group no longer operated as an intact formation. Despite its wartime collapse as a functioning organization, the 20th Air Base Group remained administratively active on the rolls until 2 April 1946, when it was inactivated. It was later disbanded on 27 September 1984. A separate 20th Airdrome Group received the 20th Air Base Group designation in 1948 as part of the 20th Fighter Wing; that later organization evolved into the 20th Mission Support Group and represents a distinct postwar institutional continuation rather than the same World War II formation in uninterrupted operation.
- 1984
Disbanded
[1]The historical group was disbanded on 27 September 1984.
- 1948
Separate 20th Airdrome Group receives designation
[1]A different unit, the 20th Airdrome Group, was renamed the 20th Air Base Group while assigned to the 20th Fighter Wing.
- 1946
Inactivated
[1]The group was inactivated on 2 April 1946 after remaining on the rolls during the war.
- 1942
Organized operations ended in the Philippines
[1]Following the end of organized American resistance in the Philippines, the group ceased to exist as an effective organized formation.
- 1941
Nichols Field attacked
[1]Japanese attacks beginning in December 1941 destroyed or disabled aircraft and disrupted the group’s normal support mission.
- 1940
20th Air Base Group formed
[1]The expanded air-base support organization was redesignated Headquarters and Headquarters Squadron, 20th Air Base Group (Reinforced), on 1 September 1940.
- 1938
Nichols Field support units consolidated
[1]The 66th Service Squadron was consolidated with the Nichols Field station complement to form the Base Headquarters and 20th Air Base Squadron.
- 1923
Redesignated 66th Service Squadron
[1]The Philippine air park became the 66th Service Squadron and took on aircraft-maintenance responsibilities.
- 1921
Air Park No. 11 established
[1]Air Park No. 11 was organized on 2 June 1921 and moved from Clark Field to Nichols Field later that year.
- 1918
66th Aero Squadron organized
[1]The 66th Aero Squadron was organized at Kelly Field, Texas, on 26 April 1918 and transferred to Eberts Field for flying-school support.
Products and positioning
A wartime air-base support and logistics organization serving United States Army Air Forces units in the Philippines.
Military support · 1938
Air base administration
Administrative support for Nichols Field and associated Army Air Forces organizations, including headquarters functions, station management, and coordination of base services.
Military logistics · 1921
Aircraft maintenance and materiel support
Second-level aircraft maintenance and materiel services delivered through the group’s service and materiel squadrons for flying units assigned to the Philippine air-defense structure.
Military logistics · 1941
Aviation ordnance support
Support from an attached aviation ordnance company for the handling and maintenance of aviation-related weapons and equipment during the prewar and early-war period.
Operational support · 1941
Weather support
The group included an Air Corps weather detachment in the Philippines for part of 1941, supporting aviation operations with meteorological information.
Brand decisions
1942
Transition from base support to ground defenseOtherBackground
Japanese attacks and the withdrawal of American aircraft and headquarters elements made normal air-base maintenance and administrative operations increasingly impracticable.
Action taken
Most available personnel were employed as ground troops as American forces concentrated around Bataan.
Aftermath
The group ceased to function as an organized military formation after the end of organized resistance in the Philippines, although its administrative status continued until 1946.
1940
Expansion into a reinforced air-base groupStrategyBackground
The Air Corps was reorganizing installation support units as overseas aviation infrastructure expanded and flying units required more integrated administrative and maintenance support.
Action taken
The Base Headquarters and 20th Air Base Squadron was expanded and redesignated as Headquarters and Headquarters Squadron, 20th Air Base Group (Reinforced), with air-base and materiel components.
Aftermath
The enlarged organization became the principal support structure for Nichols Field and associated flying units during the opening phase of the Pacific War.
Recent events
- 1984
20th Air Base Group disbanded[1]
Other
The historical 20th Air Base Group was disbanded on 27 September 1984.
- 1946
20th Air Base Group inactivated[1]
Other
The wartime group was formally inactivated on 2 April 1946 after remaining on the rolls following the 1942 collapse of organized American resistance in the Philippines.
- 1941
20th Air Base Group supports the defense of the Philippines[1]
Other
After the Pacific War began, Nichols Field was attacked by Japanese forces and the group’s aircraft-support and administrative mission was disrupted. Its personnel increasingly served in ground combat roles as American forces withdrew toward Bataan.
Sources1 sources
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