McNiece went on to make a total of four wartime combat jumps, the first as part of the Invasion of Normandy in 1944. In the same year he jumped as part of Operation Market Garden in the Netherlands, which was featured in the book (and subsequent film), "A Bridge Too Far", and at the Siege of Bastogne, part of the larger Battle of the Bulge. During fighting in the Netherlands, he was promoted to demolition platoon sergeant. He volunteered for pathfinder training, anticipating he would sit out the rest of the war training in England, but his pathfinder stick was called upon to jump into Bastogne to guide in resupply drops. His last jump was in 1945, near Prüm in Germany. In recognition of his natural leadership abilities, he ended the war as the acting first sergeant for Headquarters Company, 506th Parachute Infantry Regiment. He was discharged from the military in February 1946.