The first XXIII to go out on patrol was U-2324 on 29 Jan 1945. The U-2336 under the command of Kptlt. Klusmeier sank the last ships sunk in WWII on May 7 when he sank two British freighters inside the Firth of Forth.
None of the 6 operational XXIII's (U-2321, U-2322, U-2324, U-2326, U-2329 and U-2336) was sunk by the allies during Jan - May 1945. 4 of these boats sank or damaged 5 ships for a total of 14,601 tons.
The following 7 boats were lost to various causes;
U-2323> (mined on 26 July 1944), U-2331 (training accident on 10 Oct 1944), U-2338 (sunk by British aircraft east-northeast of Frederika on May 4, 1945, the only XXIII to be sunk by the enemy, 12 dead) U-2342 (mined on 26 Dec 1944), U-2344 (rammed by U-2336 on 18 Feb 1945), U-2351 (paid off in April 1945 after bomb damages) and U-2367 (rammed by U-boat on 5 May 1945).
31 of the remaining XXIII's were scuttled in early May 1945 and 20 more surrendered to the allies and ended their careers in Operation Deadlight. Only U-2326 (later UK sub N 35), U-2353 (later the UK sub N 37) and U-4706 (later the Norwegian Knerten) survived the war.
The XXIII was so crammed internally that she only carried two torpedoes and those had to be loaded externally in harbour, thus they lacked the offensive punch of their larger sister, the XXI Elektro boat.
All U-boats of this type
Below you can see the 61 commissioned U-boats of
Technical information for type XXIII
|sm = submerged, sf = surfaced, ph = pressure
oa = overall, hp = horsepower.