 Neither U @-@ 11 nor any of her sister boats were complete when World War I began in August 1914 . With the boats under construction at Kiel , the Austrians became convinced that it would be impossible to take delivery of the boats , which would need to be towed into the Mediterranean past Gibraltar , a British territory . As a result , U @-@ 11 and her four sisters were sold to the Imperial German Navy on 28 November 1914 . 
