The non-nuclear submarines of the German Navy prior to Germany's reunification during Cold War and afterwards have always been of supreme technology and quality, built by the legendary U-Boot shipyard "Howaldswerke - Deutsche Werft AG / HDW" in Kiel, Schleswig-Holstein.
During a joint exercise JTFEX 01-02 in 2001, the German submarine U 24 of predecessor class U 206 managed to circumvent all security and defense mechanisms around U.S. carrier "U.S.S. Enterprise" without raising their attack alert.
The submarine then fired green signal ammunition alongside the carrier, indicating a hit. It was told by German submarine crew that U 24 was so close to the carrier that they nearly touched her hull.
This year's naval exercise with German submarine participation is going to start at the beginning of March near the Azores. German Navy Commander Christian Moritz of U 32 and his crew will be leaving Eckernförde Naval Base on February 10th to make the cruise to the exercise area.
U 32, part of the latest German non-nuclear U 212 class, set a new diving world record of 2 weeks in 2006 due to the submarine's air-independent propulsion mode, powered by fuel cells with hydrogen and liquid oxygen. It's said that this fuel cell operational mode would last up to 18 days but this has not been confirmed officially yet.
Objective for the U.S. Navy is to check and enhance security of their carriers against very silent types of submarines. U 32 is barely detectable by passive sonar. With active sonar applied by destroyers or frigates in the convoy, the submarine will be able to recognize the threat earlier, then possibly applying counter-measures by firing (exercise) torpedoes first.
World Record: http://www.freerepublic.com/focus/f-news/1625676/posts