The
603th Bombardment Squadron was activated at
Ephrata Army Air Base, Washington in early 1943 as one of the four original squadrons of the
398th Bombardment Group. The squadron trained under
II Bomber Command with
Boeing B-17 Flying Fortresses. In November, replacement training ended and the squadron resumed its preparation for overseas deployment. Its parent group was the last B-17 group to be assigned to
VIII Bomber Command. The squadron flew its first combat mission the following month. Until
V-E Day the squadron participated in the air offensive against
Nazi Germany, bombing such targets as factories in
Berlin,
marshalling yards in
Saarbrücken, shipping facilities in
Kiel,
oil refineries in
Merseburg and aircraft factories in
Münster. In June 1944, prior to
Operation Overlord, the Normandy invasion, the squadron temporarily suspended its strategic bombing to attack
coastal defenses and enemy troop concentrations on the
Cherbourg peninsula.
Eighth Air Force took advantage of the diversion from strategic bombing to allow newly arrived units like the 603d to fly attacks against nearby targets to gain combat experience. The first target assigned was a
V-1 flying bomb launch site near
Sottevast, but the unit's inexperience and overcast conditions in the target area caused it to return to its home station without bombing. The squadron also struck gun positions near
Eindhoven to support
Operation Market Garden, the airborne attacks in the Netherlands, in September and attacked power stations, railroads and bridges during the
Battle of the Bulge from December until January 1945. It attacked
airfields in March 1945 during
Operation Varsity, the airborne assault across the
Rhine River. The squadron flew its last combat mission on 25 April 1945 when it attacked the airfield at
Plzeň, Czechoslovakia. After the German surrender it transported liberated
prisoners of war from Germany to France. It left Europe in May and returned to the United States aboard the , arriving at the
New York Port of Embarkation on 29 June. Squadron members were given thirty days leave, and a
cadre assembled at
Drew Field, Florida, where the squadron was inactivated in August 1945. ==Lineage==