The List of U-boat aces - sometimes known as the Aces of the Deep^{[citation needed]} - were the ten German U-Boat commanders during World War II who sank the most enemy merchant ships during their naval services, ranked according to the total tonnage of the ships they sank. The term is related to flying ace^{[citation needed]}, a World War I name for a pilot who shot down five or more enemy planes. The currently accepted list is as follows:

Otto Kretschmer

Otto Kretschmer was the most successful of the Aces of the Deep, sinking 47 merchant ships totalling 272,958 tons.

Born on May 1, 1912 in Heidau, Liegnitz and died on August 5, 1998, Kretschmer was also known as "Silent Otto" for his reluctance to make radio transmissions to U-boat headquarters (often to the infuriation of his superiors) for fear of giving away his location to Allied direction-finding posts.

Kretschmer commanded U-35, U-23, and U-99 during his time in the navy. After the war, he joined the Bundesmarine (postwar German navy), and went on to become the Chief of Staff of the NATO Command COMNAVBALTAP in May 1965, a position he held for four years. He retired in September 1970 with a rank of Flotillenadmiral.

Otto Kretschmer died in a boating accident in the summer of 1998, while celebrating his 50th wedding anniversary.

Wolfgang Lüth

Wolfgang Lüth was born in 1913 and was the second most successful one in the Aces of the Deep. During his service in the navy, he sank 46 merchant ships, for 225,204 tons. He was shot by a German sentry on May 13, 1945.

Erich Topp

Main article: Erich Topp

Born in 1914, Erich Topp is the third most successful out of the Aces of the Deep, sinking 34 merchant ships with 197,233 tons. He died on December 26, 2005.

Topp served as an advisor for the U-Boat simulation Silent Hunter II.

Heinrich Liebe

Born in 1908 and died in 1997, Heinrich Liebe is the fourth most successful among the Aces of the Deep, sinking 34 merchant ships for 187,267 tons.

Viktor Schütze

Viktor Schütze (1906-1950) sank 35 merchant ships for 180,073 tons, and was the fifth most successful among the Aces of the Deep.

Heinrich Lehmann-Willenbrock

Heinrich Lehmann-Willenbrock (December 11 1911 - April 18 1986).

During his service in the navy, Lehmann-Willenbrock commanded the submarines U-5, U-8 and U-96. U-96 was sunk in Wilhelmshaven.

One of his patrols with U-96 was documented in the novel and film Das Boot.

He placed sixth among the Aces of the Deep, sinking 24 merchant ships for 170,237 tons.

Karl-Friedrich Merten

Main article: Karl-Friedrich Merten

Born in 1905 and died in 1993, Karl-Friedrich Merten was the seventh most successful among the Aces of the Deep.

During Merten's service in the navy, he sank 27 merchant ships for 170,151 tons.

Herbert Schultze

Born in 1909 and died in 1987, Herbert Schultze was the most well known commander to the Allied forces during the war.^{[citation needed]}

As the eighth most successful out of the 10 Aces of the Deep, Schultze sank 26 merchant ships for 169,709 tons.

Günther Prien

Born in 1908 and died in 1941 during the Second World War, Günther Prien was the ninth best in the Aces of the Deep.

Prien became a national hero after he infiltrated Scapa Flow and sank the British battleship HMS Royal Oak at anchor.

During his service in the German navy, Prien sank 30 merchant ships for 162,768 tons.

His total tonnage was 211,393 from 32.5 ships over 10 cruises. His boat U-47 disappeared with all hands on March 7 1941 - cause unknown.

Georg Lassen

Georg Lassen, born in 1915, is the tenth of the 10 Aces of the Deep and the only one still living. He sank 26 ships for 156,082 tons.