SM U-66
SM U-66 was the lead ship of the U-7 class for the Austro-Hungarian Navy. She sank 24 ships with a combined gross register tonnage of 69,967 in six war patrols. She left Emden on her seventh patrol on 2 September 1917 for operations in the North Channel. Neither she nor any of her 40-man crew were ever heard from again.
