As stated on the USAAF caps page, the Army Air Force was part of the US Army and the USAAF uniforms were the same as the Army uniforms. The only visible difference was the shoulder sleeve insignia (SSI) & technical specialities patches and a wing.
The officer's winter service dress uniform is perhaps the best known example, together with the drap No. 54 color trousers. This combination became an American classic which is known as the "Pinks and Greens". The tunic was made of olive drap wool (No. 51). The trousers intended to be worn were the Pink trousers (No. 54) or the green trousers (No. 51) which matched the tunic. The summer uniform was kaki color made of cotton, gabardine, tropical worsted, etc. This uniform wasn't mandatory as opposed to the winter dress. Most officers had their uniforms tailor made but Army regulation uniforms were available at the PX.
Other uniform types saw active service with the USAAF and were worn as often as the Pinks and Greens, Ike jackets. These jackets were modelled after the British battle dress. General Dwight D. "Ike" Eisenhower popularized the jacket within the US Army during WW II. These jackets could be tailor made or cut down from a service coat. Later on, the USAAF standarized her own Ike jacket, the B-13 officer's jacket and the B-14 EM jacket.
The EM wore a green wool serge uniform, a bit lighter than the officer's coat. The trousers matched the color of the tunic. Just like the officers, EM purchased also Ike jackets or ETO jackets. This was a common practice for overseas stationned crew.
As the USAAF was less strict regarding clothing regulation, a whole variety of patches were worn. This could be cut-edge US made patches, felt , bullion, ...
Left: An American classic, the USAAF "Pinks and Greens" with a pink shirt. The black shoes are not WW II vintage, the correct shoes should be brown.
Middle: Winter service dress tunic from a flight officer with sterling pilot wings. Note the waist belt with brass buckle.
Right: Close up of bullion winged star, flight officer rank insignia and full size (3 inches) pilot wing.
Left: Pink trousers with a dark shade olive drap shirt. Trousers and shirts were worn without coat but rank insignia and wing had to be afixed to the shirt.
Right: Close up of shirt sized pilot wing (2 inches), correct rank insignia for a 2nd lieutenant and officer's side cap with DI from the S. E. Air Corps training center.
Left: Summer service dress uniform in khaki with kaki shade No. 1 shirt and trousers, officer crusher cap and side cap with ranked to a major. Note that the 2 golden major leafs are missing from the shoulders on the tunic.
Right: Close up of the collar insignia and bullion winged star shoulder patch.
Left: 1941 dated belted EM serge wool uniform as worn by a sergeant who served as a B-17 radio operator - gunner. This man stayed in the USAAF after the war, so no ruptured duck is visible. His aircrew wing is half hidden under the collar.
Right: Side view of English made felt 8th AF and communication specialist patches. The other shoulder bears a English made felt winged star. The small blue ribbon is a Presidential Unit Citation (PUC).