In late 1943, after the 82nd Airborne Division was sent to Northern Ireland, and in the early months of 1944, Ridgway helped plan the airborne operations of Operation Overlord, codename for the Allied invasion of Normandy, where he argued, successfully, for the two American airborne divisions taking part in the invasion, the 82nd and the inexperienced 101st, still commanded by Major General Lee (later replaced by Brigadier General Maxwell D. Taylor, who had formerly been commander of the 82nd Airborne Division Artillery), to be increased in strength from two parachute regiments and a single glider regiment (although with only two battalions) to three parachute regiments, and for the glider regiment to have a strength of three battalions. In the Battle of Normandy, he jumped with his troops, who fought for 33 days in advancing to Saint-Sauveur-le-Vicomte near Cherbourg (St Sauveur was liberated on June 14, 1944). Relieved from front-line duty in early July, the 82nd Airborne Division had, during the severe fighting in the Normandy bocage, suffered 46 percent casualties.