The 3d consisted of the 5th, 12th, 13th, 14th, 15th and 23d squadrons and only stayed at the airfield until 10 December, departing for La Senia Algeria as part of Operation Torch.

[7] The group consisted of the following squadrons:[7] The 355th FG flew its first combat mission, a fighter sweep over Belgium, on 14 September 1943 and afterwards served primarily as escort for Boeing B-17 Flying Fortress/Consolidated B-24 Liberator bombers that attacked industrial areas of Berlin, marshalling yards at Karlsruhe, an airfield at Neuberg, oil refineries at Misburg, synthetic oil plants at Gelsenkirchen, locks at Minden, and other objectives.

The group also flew fighter sweeps, area patrols, and bombing missions, striking such targets as air parks, locomotives, bridges, radio stations, and armoured cars.

[8] The group provided fighter cover for Allied forces landing in Normandy on 6 June 1944, and afterwards hit transportation facilities to cut enemy supply lines.

On 3 July the group transferred to Gablingen, Germany for duty with United States Air Forces in Europe as part of the army of occupation.

[9] The group consisted of the following squadrons:[10] With the departure of the Americans, Steeple Morden was transferred to RAF Fighter Command on 1 November 1945 and then was closed down on 1 September 1946 and abandoned.