It deployed to Western Europe with Ninth Air Force as a medium bombardment unit equipped with Martin B-26 Marauders.

Other targets were enemy airfields, rail junctions, fuel and ammunition stores, V-weapon sites and various military installations in France and the Low Countries.

Early in August, officially on the 5th, the 397th transferred from Rivenhall to RAF Hurn in Hampshire, to give the Marauders a better radius of action as the break-out of the Allied forces from the Normandy beachhead meant that potential targets were receding.

On the continent, the 397th struck enemy positions at St Malo and Brest and bombed targets in the Rouen area as Allied armies swept across the Seine and advanced to the Siegfried Line.

The group began flying missions into Germany in September, attacking such targets as bridges, defended areas, and storage depots.

On 1 August 1958, Strategic Air Command (SAC) organized the 4038th Strategic Wing at Dow AFB, Maine[2] and assigned it to the 820th Air Division on 1 January 1959[3] as part of SAC's plan to disperse its Boeing B-52 Stratofortress heavy bombers over a larger number of bases, thus making it more difficult for the Soviet Union to knock out the entire fleet with a surprise first strike.

[5] Starting in 1960, one third of the wing's aircraft were maintained on fifteen-minute alert, fully fueled and ready for combat to reduce vulnerability to a Soviet missile strike.

Under the Dual Deputate organization,[8] all flying and maintenance squadrons were directly assigned to the wing, so no operational group element was activated.

By 1968, Intercontinental ballistic missiles (ICBM) had been deployed and become operational as part of the United States' strategic triad, and the need for B-52s had been reduced.