U-31 (S181) is the first Type 212A submarine of the German Navy. It was built by TKMS at the shipyards of Thyssen Nordseewerke of Emden and Howaldtswerke at Kiel. The baptism took place on March 20, 2002, and the submarine was ceremonially put into service along with its sister ship U 32 by German Minister of Defence Peter Struck in Eckernförde on October 19, 2005. U 31 is powered by one diesel engine and an electric motor driven by nine fuel cells, making it virtually undetectable. Korvettenkapitän Bert Petzold is the submarine's commanding officer.