A Coast Guard manned Naval Destroyer Escort during WWII accompanies a square-rigged ship. During WWII, under an agreement made between the Commandant and the Chief of Naval Operations, Coast Guard crews manned a number of Naval Vessels, beginning in 1943. The Coast Guard's experience with sailing in shallow waters as well as on the high seas made the Coast Guard crews a valuable addition to the Allied invasion fleets. Even with Coast Guard crews, the vessels remained commissioned US Navy vessels. Thirty of these DEs, were commissioned by Coast Guard crews during the autumn of 1943. All were assigned to transatlantic-escort duty, taking convoys from the American East Coast to ports in the United Kingdom and to the Mediterranean with the threat of U-boats and, to a lesser degree, German air attack.