World War II

Antisubmarine and Alaskan service

The first predecessor of the squadron was activated at March Field, California in January 1941 as the 21st Bombardment Squadron (Heavy),one of the original squadrons of the 30th Bombardment Group. The 21st was equipped with a mix of Douglas B-18 Bolo, Boeing YB-17 Flying Fortress, and Lockheed A-29 Hudson aircraft. In May, the squadron moved to New Orleans Airport, where it continued training as a bomber unit.^[4][5]

When the Japanese attacked Pearl Harbor, the squadron began antisubmarine patrols over the Gulf of Mexico and dispatched a detachment to Savannah Army Air Base, Georgia^{[lower-alpha 2]} to hunt for U-boats off the Atlantic Coast. By the end of the month, though, the squadron was patrolling the Pacific Coast with its Hudsons, the 30th Group having returned to March Field after a brief stay at Muroc Army Air Field, California. From May through June 1942, the squadron operated through detachments at McChord Field, Washington and Hamilton Field as well as at civilian airports in Southern California.^[4][5]

21st Bomb Squadron B-24 Liberator at Amchitka in March 1943

in June 1942, the Japanese attacked Dutch Harbor, Alaska. The squadron's air echelon moved to Fort Glenn Army Air Base, on Umnak Island, Alaska to reinforce the 28th Composite Group in the Aleutian Islands, using the Consolidated B-24 Liberator and the LB-30 model of the Liberator. By September, the rest of the squadron had joined it in Alaska.^[4] The squadron frequently operated from advanced bases in the Aleutian Chain. On 14 September, along with the 404th Bombardment Squadron of the 28th Group, it conducted the first raid from Adak Army Air Field, an attack on Japanese naval forces at Kiska. By February 1943, American forces had occupied Amchitka, and the squadron began operating from Amchitka Army Air Field. On 18 July, the squadron provided planes that, along with planes from the 36th and 404th Squadrons, attacked Shimushu and Paramushiru in the Kuril Islands. Although the attack caused little damage, it was the first attack on Japan itself after the Doolittle Raid.^[6]

Although the squadron spent fifteen months operating under the control of the 28th Group in Alaska, it remained formally assigned to the 30th Group at March Field. By September 1943, when the Aleutian Campaign had ended and the squadron was released to return to the United States, the 30th Group and its remaining squadrons had departed for the Pacific, and the squadron was disbanded at Smoky Hill Army Air Field, Kansas on 1 November.^[4][5][7]

Strategic bombing of Japan

501st Bombardment Group B-29 taking off from Northwest Field Guam

The second predecessor of the squadron was the 21st Bombardment Squadron, Very Heavy, which was activated at Dalhart Army Air Field, Texas as one of the original four squadrons of the 16th Bombardment Group. However, before the squadron could be manned or equipped, groups flying the Boeing B-29 Superfortress were reorganized from four bombardment squadrons with seven aircraft each to three bombardment squadrons with ten aircraft each^[8] and the squadron was inactivated on 10 May 1944.^[9]

The squadron's inactivation lasted only three weeks, however, and on 1 June it was again activated at Dalhart, this time as a component of the 501st Bombardment Group. In August, the squadron moved to Harvard Army Air Field, Nebraska, where it trained for combat with the Superfortress. It left Harvard in March 1945 after completing its training and arrived at its combat station, Northwest Field, Guam, on 14 April. The squadron flew its first combat mission against Truk Island on 19 June, and eight days later made its first attack on Japan. The unit's missions focused on Japan's petroleum facilities on Honshu. In July 1945, it received a Distinguished Unit Citation for attacks on the Maruzen oil refinery at Shimotso, the Utsobo oil refinery at Yokkaichi and storage facilities at Kawasaki.^[9][10]

After VJ Day, the squadron dropped food and supplies to prisoners of war in Japan, China, Korea and Manchuria. The squadron remained on Guam until it was inactivated in June 1946.^[9][10]

Vietnam War

The 21st Tactical Air Support Squadron was organized at Pleiku Air Base, South Vietnam on 8 May 1965, as one of three squadrons activated to augment the 19th Tactical Air Support Squadron, which had been operating in the forward air control mission in South Vietnam since 1963.^[11] It initially flew Cessna O-1 Bird Dog aircraft in the forward air control mission. However, it was not until August that the squadron became operational. The 21st operated primarily in the II Corps Area, with its aircraft dispersed to support United States Army, ARVN and Korean units.^[12] While initially organizing, it directed air strikes during the Battle of Duc Co^[13]

The squadron performed visual reconnaissance with light aircraft, flying slowly at low altitude. By patrolling the same area regularly, squadron forward air controllers grew familiar with the terrain and learned to detect changes that could indicate enemy forces hiding below. The controller called in fighter-bombers and marked targets with smoke grenades or white phosphorus rockets. After the attacks, controllers flew low over the target to assess the damage.^[12] In September 1966, the 21st moved from the highlands of Pleiku to the coastal base of Nha Trang Air Base.^[14]

21st Squadron Cessna O-2A

On 27 February 1967, Captain Hilliard A. Wilbanks, one of the squadron's forward air controllers, was flying visual reconnaissance in his Cessna O-1 ahead of a South Vietnamese ranger battalion. He located a well-concealed numerically superior Viet Cong (VC) force poised to ambush the rangers. The enemy immediately fired on his plane and advanced on the ranger force, which was pinned down by devastating fire. Capt. Wilbanks recognized that close air support would not be able to arrive soon enough to help the rangers to withstand the advancing enemy. Flying through withering fire at treetop level, he flew over the VC and inflicted many casualties by firing his rifle out the side window of his Bird Dog. Despite increasingly intense antiaircraft fire, he made repeated low passes over the VC. His tactics interrupted the VC's advance and allowed the rangers to withdraw to safety. During his final attack, Capt. Wilbanks was mortally wounded and his aircraft crashed between the opposing forces. He saved numerous friendly personnel from certain injury or death. For his action that day, he was awarded the Medal of Honor.^[15]

The single engine of the O-1 Bird Dog made it particularly vulnerable to ground fire and it lacked radio equipment that would permit it to communicate with ground troops and attacking aircraft at the same time. Its low speed and endurance, in addition to making it more vulnerable, sometimes delayed its arrival in areas of operation and the time it could operate.^[16] In 1968, the squadron began equipping with twin engined, faster Cessna O-2 Skymasters that had higher speed, greater endurance and better communications equipment, although the O-1 would not be completely phased out of squadron operations until 1971. The 21st moved to Cam Ranh Bay Air Base, South Vietnam in September 1969, and to Phan Rang Air Base two years later. As the United States withdrew forces from Vietnam, the squadron moved to Tan Son Nhut Air Base in January 1972 and was inactivated there on 21 February 1973.^[14] Aircraft losses during the war included 41 O-1s, 16 O-2s and an OV-10, while 29 crewmembers lost their lives in combat.^[13][17]

Cold War

Squadron OV-10 firing rockets during an exercise near Shaw AFB

The squadron was again activated at MacDill Air Force Base, Florida, at the end of August 1973.^[18] At MacDill, it was equipped with the Cessna OT-37 Tweet and was assigned to the 68th Tactical Air Support Group, which was located at Shaw Air Force Base, South Carolina.^[19][20] Little less than a year later, on 1 July 1974, it moved to Shaw, where it joined its parent 507th Tactical Air Control Group, which assumed the mission of the 68th Group when the 68th was inactivated in June 1974.^[19][21] At Shaw, the squadron converted from the OT-37 to the OV-10 Bronco in 1988. It re-equipped with the Fairchild Republic OA-10 Thunderbolt II in 1991, shortly before being inactivated and transferring its mission, equipment and personnel to the 21st Tactical Fighter Squadron in November 1991.

Testing, evaluation and analysis

The squadron was redesignated the 21st Test and Evaluation Squadron and activated on 15 September 1992 at Randolph Air Force Base, where it was assigned to the 12th Operations Group. It absorbed the resources of the 3307th Test and Evaluation Squadron, which had been activated on 15 September 1991 and assigned to the 3300th Training Support Group, and which was simultaneously inactivated.^[22][23] Air Training Command (ATC) had established the 3307th Squadron to perform tests and evaluations of new ATC systems including aircraft, simulators and software to determine if these acquisitions met operational requirements.

The squadron became the Air Education and Training Command Studies and Analysis Flight at the end of March 1994. In April 1997, it added the resources of the 602d Training Support Squadron at Edwards Air Force Base, California, which developed training programs for new weapons systems as they were acquired by the Air Force and became a squadron again.^[14] Personnel at Edwards formed Detachment 1 of the squadron. The Edwards detachment later downgraded to Operating Location A in 2003, and its mission and personnel were absorbed by the squadron at Randolph in 2008. The squadron currently includes a technology innovation flight and a strategy analysis flight.

Assignments

• 30th Bombardment Group, 15 January 1941 (under operational control of 28th Composite Group, 9 January 1942–September 1943)
• Second Air Force, 18 October 1943 – 1 November 1943
• 16th Bombardment Group, 1 April 1944 – 10 May 1944
• 501st Bombardment Group, 1 June 1944 – 10 June 1946^[24]
• Pacific Air Forces, 28 April 1965 (not organized)
• 2d Air Division, 8 May 1965 (attached to Tactical Air Support Group 6250th, Provisional after 1 August 65)
• 505th Tactical Control Group, 8 November 1965 (attached to Tactical Air Support Group, Provisional, 6250th 1–8 September 1966, Tactical Air Support Group, Provisional, 6253d after 9 September 1966)
• 504th Tactical Air Support Group, 8 December 1966
• 377th Air Base Wing, 15 November 1972 – 21 February 1973^{[lower-alpha 3]}
• 68th Tactical Air Support Group, 31 August 1973^[19]
• 507th Tactical Air Control Group (later 507th Tactical Air Control Wing), 15 June 1974 – 1 November 1991
• 12th Operations Group, 15 September 1992^[23]
• Air Education and Training Command, 31 March 1994 – present^[14]

Stations

Aircraft

• Douglas B-18 Bolo, 1941
• Boeing YB-17 Flying Fortress, 1941
• Lockheed A-29 Hudson, 1941-1942
• Consolidated LB-30 Liberator, 1942
• Consolidated B-24 Liberator, 1942-1943
• Boeing B-29 Superfortress, 1944-1946
• Cessna O-1 Bird Dog, 1965-1971
• Cessna O-2 Skymaster, 1968-1973
• North American OV-10 Bronco, 1971, 1973-1988, 1989-1991
• Sikorsky CH-3, 1975-1977
• Cessna OT-37 Dragonfly, 1986-1988
• Fairchild Republic OA-10 Thunderbolt II, 1991^[14]

Awards and campaigns

Award streamer	Award	Dates	Notes
	Distinguished Unit Citation	Japan, 6 July 1945-13 July 1945	21st Bombardment Squadron, Very Heavy[9]
	Presidential Unit Citation	8 August 1966-7 August 1967	21st Tactical Air Support Squadron[26]
	Presidential Unit Citation	8 August 1967-7 August 1968	21st Tactical Air Support Squadron[26]
	Presidential Unit Citation	1 August 1968-31 August 1969	21st Tactical Air Support Squadron[27]
	Presidential Unit Citation	1 January 1970-31 December 1970	21st Tactical Air Support Squadron[27]
	Presidential Unit Citation	30 January 1971-31 December 1971	21st Tactical Air Support Squadron[27]
	Air Force Outstanding Unit Award with Combat "V" Device	15 March 1972-21 February 1973	21st Tactical Air Support Squadron[27]
	Air Force Outstanding Unit Award	16 Jun 1975-31 May 1977	21st Tactical Air Support Squadron[28]
	Air Force Outstanding Unit Award	1 May 1981-30 April 1983	21st Tactical Air Support Squadron[28]
	Air Force Outstanding Unit Award	1 May 1985-30 April 1987	21st Tactical Air Support Squadron[28]
	Air Force Outstanding Unit Award	15 September 1992-30 June 1993	21st Test & Evaluation Squadron[28]
	Air Force Outstanding Unit Award	1 July 1993-3 March 1994	21st Test & Evaluation Squadron[28]
	Air Force Organizational Excellence Award	1 January 2006-31 December 2007	AETC Studies & Analysis Squadron[29]
	Air Force Organizational Excellence Award	1 January 2013-31 December 2014	AETC Studies & Analysis Squadron[29]
	Vietnamese Gallantry Cross with Palm	8 May 1965-21 February 1973	21st Tactical Air Support Squadron[27][28][lower-alpha 4]

Campaign Streamer	Campaign	Dates	Notes
	Antisubmarine	7 December 1941 – 7 June 1942	21st Bombardment Squadron (Heavy)[4]
	Air Offensive, Japan	7 June 1942 – 19 September 1943 14 April 1945 – 2 September 1945	21st Bombardment Squadron (Heavy)[4] 21st Bombardment Squadron, Very Heavy[9]
	Aleutian Islands	7 June 1942 – 24 August 1943	21st Bombardment Squadron (Heavy)[4]
	Eastern Mandates	14 Apr 1945	21st Bombardment Squadron, Very Heavy[9]
	Western Pacific	17 April 1945 – 2 September 1945	21st Bombardment Squadron, Very Heavy[9]
	Vietnam Defensive	8 May 1965 – 30 January 1966	21st Tactical Air Support Squadron[26]
	Vietnam Air	31 January 1966 – 28 June 1966	21st Tactical Air Support Squadron[27]
	Vietnam Air Offensive	29 June 1966 – 8 March 1967	21st Tactical Air Support Squadron[27]
	Vietnam Air Offensive, Phase II	9 March 1967 – 31 March 1968	21st Tactical Air Support Squadron[27]
	Vietnam Air/Ground	22 January 1968 – 7 July 1968	21st Tactical Air Support Squadron[27]
	Vietnam Air Offensive, Phase III	1 April 1968 – 31 October 1968	21st Tactical Air Support Squadron[27]
	Vietnam Air Offensive, Phase IV	1 November 1968 – 22 February 1969	21st Tactical Air Support Squadron[27]
	Tet 1969/Counteroffensive	23 February 1969 – 8 June 1969	21st Tactical Air Support Squadron[27]
	Vietnam Summer-Fall 1969	9 June 1969 – 31 October 1969	21st Tactical Air Support Squadron[27]
	Vietnam Winter-Spring 1970	3 November 1969 – 30 April 1970	21st Tactical Air Support Squadron[27]
	Sanctuary Counteroffensive	1 May 1970 – 30 June 1970	21st Tactical Air Support Squadron[27]
	Southwest Monsoon	1 July 1970 – 30 November 1970	21st Tactical Air Support Squadron[27]
	Commando Hunt V	1 December 1970 – 14 May 1971	21st Tactical Air Support Squadron[27]
	Commando Hunt VI	15 May 1971 – 31 July 1971	21st Tactical Air Support Squadron[27]
	Commando Hunt VII	1 November 1971 – 29 March 1972	21st Tactical Air Support Squadron[27]
	Vietnam Ceasefire Campaign	29 March 1972 – 28 January 1973	21st Tactical Air Support Squadron[27]

Notes

Explanatory notes

Citations

Bibliography

 This article incorporates public domain material from the Air Force Historical Research Agency

• Cate, James L. (1953). "The Twentieth Air Force and Matterhorn, Chapter 4, XX Bomber Command against Japan". In Craven, Wesley F.; Cate, James L. (eds.). The Army Air Forces in World War II (PDF). Vol. V, The Pacific: Matterhorn to Nagasaki. Chicago, IL: University of Chicago Press. LCCN 48003657. OCLC 704158. Retrieved 17 December 2016.
• Hobson, Chris (2001). Vietnam Air Losses: United States Air Force, Navy and Marine Corps Fixed-Wing Aircraft Losses in Southeast Asia 1961–1973. Naperville, IL: Midland Publications. ISBN 9781857801156.
• Lester, Gary R. (1997). Mosquitos to Wolves: The Evolution of the Airborne Forward Air Controller (PDF). Maxwell AFB, AL: Air University Press. ASIN B00010WU1G. Retrieved 11 July 2018.
• Maurer, Maurer, ed. (1983) [1961]. Air Force Combat Units of World War II (PDF) (reprint ed.). Washington, DC: Office of Air Force History. ISBN 0-912799-02-1. LCCN 61060979. Retrieved 17 December 2016.
• Maurer, Maurer, ed. (1982) [1969]. Combat Squadrons of the Air Force, World War II (PDF) (reprint ed.). Washington, DC: Office of Air Force History. ISBN 0-405-12194-6. LCCN 70605402. OCLC 72556. Retrieved 17 December 2016.
• Mueller, Robert (1989). Air Force Bases, Vol. I, Active Air Force Bases Within the United States of America on 17 September 1982 (PDF). Washington, DC: Office of Air Force History. ISBN 0-912799-53-6. Retrieved 17 December 2016.
• Ravenstein, Charles A. (1984). Air Force Combat Wings, Lineage & Honors Histories 1947-1977. Washington, DC: Office of Air Force History. ISBN 0-912799-12-9. Retrieved 17 December 2016.
• Walton, LCDR Andrew R. (2004). The History of the Airborne Forward Air Controller in Vietnam (PDF). Fort Leavenworth, KS: U.S. Army Command and General Staff College. Archived (PDF) from the original on 16 September 2020. Retrieved 13 July 2018.
• Watkins, Robert A. (2013). Insignia and Aircraft Markings of the U.S. Army Air Force In World War II. Vol. V, Pacific Theater of Operations. Atglen,PA: Shiffer Publishing, Ltd. ISBN 978-0-7643-4346-9.
• "AF Pamphlet 900-2, Unit Decorations, Awards and Campaign Participation Credits" (PDF). Washington, DC: Department of the Air Force Index. 15 June 1971. Archived from the original (PDF) on 4 August 2015. Retrieved 11 August 2016.
• "AF Pamphlet 900-2, Unit Decorations, Awards and Campaign Participation Credits, Vol II" (PDF). Washington, DC: Department of the Air Force. 30 September 1976. Archived from the original (PDF) on 4 August 2015. Retrieved 11 August 2016.
• "12th Flying Training Wing History". 12th Flying Training Wing Office of History. July 2011. Retrieved 11 July 2018.