Structure of the USAAF – Airforces

The structure of the American Air Force is complex and confusing. Much of it was formed hurriedly during the Second World War, but elements can be traced back as far as the First World War. At its peak, there were almost 2.5 million people employed within its scope both within the United States and overseas in one of the many theatres of operation.

At the start of the Second World War, there were 4 air forces, (designated by district), which were then renumbered 1 – 4 in early 1941. These stayed based within the U.S. covering the West Coast and some training operations on the East Coast and in the southern U.S. The newly established forces were then formed for overseas service. The Fifth, Seventh, Tenth, Thirteenth, Fourteenth and Twentieth covering the Pacific / Asia campaigns; the Eighth, Ninth, Twelfth and Fifteenth, the European / African / Middle East Theatre; the Sixth covering Panama and finally the Eleventh covering Alaska. During the period 7th December 1941 to 2nd September 1945, there were 16 individual Air Forces forming the entire American Air Arm.

Within these Air Forces, were Commands, and due to the complex nature and size of some of these Commands, some were further split into smaller Divisions. These Divisions would then manage a number of Wings each with similar roles and each having groups beneath them. These groups were wide in their roles, but basically slotted into one of four areas: Bombardment, Fighter, Reconnaissance and Troop Carrier.  So ideally, a Wing would provide a set role in any of the given theatres. However, due to the nature of the conflict, many of these Wings would contain within them, groups of differing roles: fighter, bombardment etc., causing further confusion. In addition to this, there were also further Commands that were not part of any numbered air force and they had a separate command structure of their own.

Beneath the groups, there were the squadrons, the front-line units and, in the period 7th December 1941 – 2nd September 1945, there were 1,226 active squadrons operating across the globe.

The mobility, disbandment and reactivation of individual squadrons, groups or units, makes it virtually impossible to say for certain, how many were active during any given period of time, certainly without access to detailed government files.  So, these figures are not necessarily truly accurate.

I hope this short guide helps to clarify the general structure of the USAAF, and in the following, I detail a little bit more about each air force, its formation and scope of operation. The dates in parentheses give the known date of the officially naming and not necessarily the date of formation.

If you spot any errors, please let me know and I will endeavour to correct them as quickly as possible.

Air Forces

First Air Force (September 18th, 1942)

Approved January 18th, 1944 (Wikipedia)

One of the original four numbered air forces, the First AF was originally constituted as the Northeast Air District on October 19th, 1940 and activated on December 18th, 1940. It was re-designated 1st Air Force on April 9, 1941, and then the ‘First Air Force’ on September 18, 1942. On September 17th, 1943, it was assigned to the Army Air Forces.

Its purpose was to train staff for new organisations and, later, replacements for combat busy units. In addition, the First AF units were responsible for the entire air defence of the eastern United States until the end of 1943.

 Second Air Force (September 18th, 1942)

Second Air Force - Emblem (USAF).png

Second Air Force (Wikipedia)

The Second Air Force was initially constituted as the Northwest Air District on October 19th, 1940. It was then activated on December 18th, 1940, as an element of the Central Defence Command, U.S. Army. It was then designated the 2nd Air Force on April 9th, 1941, and re-designated ‘Second Air Force’ on September 18, 1942, when it was an element of the Western Defence Command. Their role in the Second was both as air defence and to train units and replacements for heavy (H) and, later on, very heavy (VH) bombardment operations.

Third Air Force  (September 18th, 1942).

Approved September 1st, 1943 (Wikipedia)

The Third Air Force was originally constituted as the Southeast Air District on October 19th, 1940. Activated on December 18th, 1940, it was assigned to the Southern Air Command, designated the 3rd Air Force on April 9th, 1941, and its formal title ‘Third Air Force’ on September 18th, 1942. The Third carried out air defence duties during 1940 – 41 and engaged in antisubmarine activities from December 1941 to October 1942. It was assigned to the Army Air Forces in September 1943, and continued training units, crews, and individuals for bombardment, fighter, and reconnaissance operations.

Fourth Air Force  (September 18th, 1941)

Approved September 1st, 1943 (Wikipedia)

The Fourth Air Force, was originally constituted as the Southwest Air District on October 19th, 1940, and was activated in the following December, on December 18th, 1940, as part of the General Headquarters Air Force, and was subsequently subordinate to the Western Defence Command. It was designated the 4th Air Force on April 9th, 1941, and re-designated ‘Fourth Air Force’ on September 18th, 1941. They  provided air defence for the western US until 1943, whilst at the same time trained new air combat organisations ready for conflict. Later in the war, the Fourth Air Force was engaged primarily in training replacements for combat duties.

 Fifth Air Force (September 18th, 1942)

File:Fifth Air Force - Emblem.png

Approved March 25th, 1943 (Wikipedia)

One of the few numbered air forces that never served on its own soil, the Fifth was constituted as the Philippine Department Air Force on August 16th, 1941. It was activated in the Philippines on September 20th, 1941, and then re-designated the Far East Air Force on October 28th, that same year. Then on February 5th 1942, is gained a further title the 5th Air Force.  Finally, it was given its formal title of the ‘Fifth Air Force’ on September 18th, 1942. This air force lost most of its men and equipment in the defence of the Philippines after the Pearl Harbour attack on December 7th, 1941. Later that same month, the headquarters and some crews along with their aircraft moved to Australia, and in January 1942 they were sent to Java to help delay Japanese advances in the Dutch Indies. The Fifth did not function as an air force for some time after February 1942 (the AAF organisations in the South-west Pacific being under the control of American-British-Dutch- Australian Command and later Allied Air Forces). The headquarters were re-manned in September 1942 and they assumed control of all AAF organisations in both Australia and New Guinea. The Fifth participated in operations that stopped the Japanese drive in Papua, recovered New Guinea, neutralised islands in the Bismarck Archipelago, the Dutch East Indies, and liberated the Philippines. Before the war ended in August 1945 elements of the Fifth were moved to the Ryukyu Islands ready for the invasion of Japan.

Sixth Air Force (September 18th, 1942)

 6th Air Force

Sixth Air Force (US Army Museum)

On October 19th, 1940, the  Sixth Air Force was constituted but known as the Panama Canal Air Force, which was activated in the Canal Zone on November 20th, 1940. It was then re-designated the Caribbean Air Force on August 5th, 1941, and then as the 6th Air Force on February 5th, 1942. Finally, it became known as the ‘Sixth Air Force’ on September 18th, 1942, serving primarily in defence of the Panama Canal and  in anti-submarine operations.

 Seventh Air Force (September 18th, 1942)

Approved May 21st, 1943 (Wikipedia)

The Seventh Air Force was constituted as the Hawaiian Air Force on October 19th, 1940, and activated in Hawaii on November 1st, 1940. It was re-designated the 7th Air Force on February 5th, 1942, and as the ‘Seventh Air Force’ on September 18th, 1942. Its role was to provide air defence for the Hawaiian Islands area and, after mid-1943, served in combat in the central and western Pacific areas.

Eighth Air Force on February 22nd, 1944

Eighth Air Force - Emblem.png

Eighth Air Force (Wikipedia)

The Eighth Air Force, possibly the most well-known of all the air forces, began its existence when it was formed as the VIII Bomber Command on January, 19th, 1942. It was then activated in the United States on February 1st, 1942. An advanced detachment was established in England at the end of February (23rd) and units began arriving from the United States during the spring of 1942.  Here the command carried out the heavy bombardment operations of Eighth Air Force (see also US Strategic Air Forces in Europe) from August 17th, 1942, until early in 1944, when it was eventually re-designated as the ‘Eighth Air Force’ (February 22nd,1944).

Afterwards, the Eighth were engaged primarily in bombardment of strategic targets across Europe. It transferred, without its personnel, equipment, or combat elements, to Okinawa on July 16th, 1945. Although some personnel and combat units were assigned before V-J Day, the Eighth did not participate in combat activities against Japan.

 Ninth Air Force (September 18th, 1942)

Approved September 16, 1943.) (Wikipedia)

The Ninth Air Force derived from an element constituted as V Air Support Command on August 21st, 1941. It was activated on September 2nd, 1941, as part of the Air Combat Command, and was re-designated 9th Air Force on April 9th, 1942. Finally, it was designated as the ‘Ninth Air Force’ on September 18th, 1942. The organisation then moved to Egypt to begin operations. On November 12th, that year, they participated in the Allied drive across Egypt and Libya, along with the campaign in Tunisia, and the invasions of both Sicily and Italy. Transferring back to England on October 16th, 1943, the Ninth became the tactical air force for the forthcoming planned invasion of Europe. The Ninth helped isolate the battlefield in preparation for the Allied assault on the Normandy beaches; they then supported those operations and throughout June 1944, supported the drive that carried the Allies through France and then on into  Germany and finally victory in May 1945.

Tenth Air Force (February 4th, 1942).

Approved January 25th, 1944) (Wikipedia)

The Tenth Air Force was constituted on February 4th, 1942, and activated on February 12th as an element of the Air Combat Command. It moved to India on March 5th, 1942, and served in the India-Burma Theater and in China until March 1943 when the Fourteenth Air Force was activated in China. Then the Tenth operated in India and Burma until it moved to China late in July 1945, where it remained until the end of the conflict.

Eleventh Air Force (September 18th, 1942)

File:Eleventh Air Force - Emblem.png

Approved August 13th, 1943 (Wikipedia)

Constituted on December 28th, 1941, and activated in Alaska on January 15th, 1942. It was re-designated 11th Air Force on February 5th, 1942, and as ‘Eleventh Air Force’ on September 18th, 1942. It participated in the offensive that drove the Japanese from the Aleutians, attacked the enemy in the Kurile Islands, and served as part of the defence force for Alaska.

Twelfth Air Force (August 20th, 1942)

File:Twelfth Air Force - Emblem.png

Approved December 1st, 1943 (Wikipedia)

The Twelfth Air Force was constituted on August 20, 1942, and activated the same day. It moved to England on September 12th, 1942, and then to North Africa for the invasion of Algeria and French Morocco on November 9th, 1942. The Twelfth operated in the Mediterranean theatre until the end of the war, serving with Northwest African Air Forces from February to December 1943, and afterwards with Mediterranean Allied Air Forces.

Thirteenth Air Force (January 13th, 1943)

File:Thirteenth Air Force - Emblem.png

Approved January 18th, 1944 (Wikipedia)

The Thirteenth Air Force was constituted on December 14th, 1942, and activated on New Caledonia on January 13th, 1943. It served in the South Pacific and, later, Southwest Pacific, participating in the Allied drive north and west from the Solomons to the Philippines. It remained in the Philippines as part of Far East Air Forces.

Fourteenth Air Force (March 5th, 1943)

Approved August 6th, 1943 (Wikipedia)

The Fourteenth Air Force was constituted on March 5th, 1943, and activated in China on March 10th. It served in combat against the Japanese, operating primarily in China, until the end of the war.



Fifteenth Air Force (October 30th, 1943)

Approved February 19th, 1944 (Wikipedia)

The Fifteenth Air Force was constituted on October 30th, 1943, and activated in the Mediterranean Theatre on November 1st, that same year. It began
operations on November 2nd and engaged primarily in strategic bombardment of targets in Italy, France, Germany, Poland, Czechoslovakia, Austria, Hungary, and the Balkans until the end of the war.

The Twentieth Air Force (April 4th, 1944)

Approved May 26th, 1944 (Wikipedia)

The Twentieth Air Force was constituted on April 4th, 1944, and activated the same day in Washington, D.C., as an element of the Army Air Forces. Though operating from bases around the Pacific Ocean, the organisation remained under the direct control of the commanding general of the Army Air Forces throughout the summer of 1945.  Some combat elements moved from the United States to India in the summer of 1944, where they carried out very heavy bombardment operations against targets in Japan, Formosa, Thailand, and Burma. Other combat elements began moving late in 1944 from the United States to the Marianas, being joined there early in 1945 by the elements that had been in India. The headquarters, which had remained in the United States, was transferred to Guam in July 1945. From the Marianas, the Twentieth conducted a strategic air offensive that reached a climax with attacks using the world’s first atomic bombs against the two Japanese cities, Hiroshima and Nagasaki.

U.S. Strategic Air Forces in Europe (February 22nd, 1944)

Approved December 21st, 1944 (Wikipedia)

This command was originally constituted as the Eighth Air Force on January 19th, 1942, and activated on January 28th. It moved to England, May – June 1942 and engaged primarily in bombardment of targets in Europe.

Re-designated U.S. Strategic Air Forces in Europe February 22nd, 1944, the former element of the Eighth coordinated the activities of Army Air Forces in the EAME Theatre, exercising some operational control over both Eighth Air Force (originally VIII Bomber Command) and Fifteenth Air Force with some administrative control over the Eighth and Ninth Air Forces. The organisation was re-designated United States Air Forces in Europe in August 1945.

Far East Air Forces (August 3rd, 1944)

File:Far East Air Forces - Emblem 1954.png

US Far East Air Force (Wikipedia)

Far East Air Forces was constituted as a provisional command on July 31st, 1944, and reconstituted as a regular unit and activated on August 3rd, 1944, to control the operations of Fifth and Thirteenth Air Forces.




Continental Air Forces (December 13th, 1944)

The Continental Air Forces was constituted on December 13th, 1944, and activated on December 15th as an element to control the activities of all the numbered air forces that remained in the United States during the war.


This information was taken from Air Force Combat Units of World War II, published by the Office of Air Force History, edited by Dr. Maurer Maurer (1959) republished 1989. For more detailed information on bases, commanders, citations click here.

29 thoughts on “Structure of the USAAF – Airforces

  1. Fascinating explanation . I believe it was the Fifth Air Force that tested atomic bombs in the 1950s on Pacific Islands. My father ( a Navy man at a couple of those tests ) had some Fifth Air Force year books from that time . You inspired me to do little more research .

    Liked by 2 people

  2. Excellent, thorough work as always. Anybody who doesn’t know this web site should try clicking on
    “ME AND MY TRAILS” which deals with what many of the Eighth Air Force air bases are like today.

    Liked by 2 people

  3. Two comments GP. Sometimes require tactical responses and individual airforces as the need arrives. Second your description reminds me of our reaction to driving around Gettysburg seeing multiple monuments to each states regiments that served in the battle. Knowing each state differed in size the question formed what constitutes a regiment ? And finally finding the description only clarified the answer a little. To put it simply the size of various state regiments varied. And I think that is part of why history can be in interesting subject. Thanks for filling in some of those bits of history.

    Liked by 1 person

  4. Fascinating. My mother lost one brother (B-25 copilot) who served in New Guinea in the 5th AF, and another (P-38) pilot who served in Italy with the 15th. Their youngest brother was killed (the day the second atomic bomb was dropped) when the engine of his P-40 threw a rod and exploded–in Texas. That day his other brothers were still MIA.

    Liked by 2 people

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.