In preparation for the Invasion of Normandy, the regiment participated in invasion rehearsal exercises, using landing craft, vehicle, personnel (LCVP) and Landing Craft Assault (LCA). For the invasion, the regiment was part of Force O, the initial assault force. The regiment was to lead the assault on Omaha Beach to the west of 1st Division's 16th Infantry, and would be temporarily attached to 1st Division. H-Hour, the beginning of the invasion, was scheduled for dawn on 5 June (D-Day, the first day of the assault). Companies A, E, F, and G were to be in the first wave of the assault on Omaha Beach. The beach was divided into sectors: Company A, the westernmost, was to land at Dog Green, Company G at Dog White, Company F at Dog Red, and Company E at Easy Green on the right of 16th Infantry. It was planned that by 09:30 on D-Day, the beach exits would be open and vehicles able to leave the beach. 1st Battalion was to take Vierville, link up with the ranger group advancing east along the coastal highway, and advance on Vire. Meanwhile, 2nd Battalion would capture Saint-Laurent and the heights southwest of it. 3rd Battalion constituted the reserve, and was tasked with advancing to Longueville.