Strategic attacks on different vessel types with an emphasis on freighters and tankers
During this time, the German Navy targeted valuable ships that were contributing to the war overseas. Some of the vessel types that were torpedoed were freighter steam boats which were carrying equipment, and materials headed across the Atlantic Ocean to aid Americans and allies in the warzones. Another targeted boat were oil tankers, because of its important contents and value. The strategic attacks by German U-boats were the cause for specific vessel types such as freighters and tankers peaks in the data set during the WWII time frame.
“By 1943, the tide in the U-boat war was turning against Admiral Donitz, Germany’s supreme submarine admiral. His best commanders were dying, the ratio of U-boat losses to allied tonnage sunk was rising, and the amount of ocean free allied air surveillance was decreasing rapidly.” – Norton, Naval War College Review