Aside from its already remarkable design, the Grayback had two propellers that were driven by four electric motors. These were, in turn, charged and powered by a quartet of diesel-powered engines that were powerful enough to run the sub. On its list were a crew of 54 enlisted men and six officers. Of course, the numbers weren’t accurate as it was discovered that she actually had a total of 80 men on board when it disappeared in 1944.