The Type XXIII was a wartime answer to a wartime problem. By 1943 the Battle of the Atlantic had turned against Germany, partly because Allied anti-submarine warfare had become brutally effective. The XXIII was a small coastal U-boat designed for fast underwater work in confined waters - the North Sea, the Mediterranean, the Baltic - rather than long Atlantic patrols. She displaced 234 tonnes surfaced, 258 tonnes submerged, and was just 34.68 metres long. The single MWM six-cylinder diesel made 575 horsepower; a double-acting AEG electric motor pushed 580; a small BBC silent-running motor handled creeping. Top submerged speed was 12.5 knots - faster underwater than on the surface, which was a remarkable inversion for the time. She carried two 53.3cm torpedo tubes and just two preloaded torpedoes. No deck gun. Crew: 14 to 18.

U-2367 was ordered on 20 September 1944 and laid down at Deutsche Werft AG in Hamburg on 11 December 1944 as yard number 521. She was launched on 23 February 1945 and commissioned on 17 March under Oberleutnant zur See Heinrich Schroeder. The build had taken three months and one week. The pace reflects both the simplicity of the Type XXIII design and the desperation of late-war German production - assembly was being attempted at a speed that pre-war shipyards would have considered reckless. By the time U-2367 was commissioned, Allied armies were across the Rhine, the Soviets were at the Oder, and the Hamburg yards themselves were operating under Allied bombing. The crew that boarded her had been trained for a war that was already nearly over.

On 5 May 1945, Grand Admiral Karl Doenitz - newly appointed Reichsprasident after Hitler's suicide - issued Regenbogen, the order for German U-boats to be scuttled rather than handed to the Allies. Many crews carried it out. Many others were already trying to escape across the Baltic, ferrying refugees away from the advancing Soviet armies. In the chaos of that day, U-2367 collided with another unidentified German U-boat near Schleimuende, at the eastern entrance to the Schlei fjord. She sank. The crew, by most accounts, survived the incident. The ceasefire for German forces in northwest Europe had taken effect that same day; the formal surrender at Reims was three days away. The wreck settled into the shallow Baltic at a position that has been precisely recorded but not widely published.

U-2367 did not stay on the seabed. In August 1956, with West Germany now a NATO member and rebuilding a small navy as the Bundesmarine, divers raised her from the Baltic. Eleven years on the bottom had done less damage than might have been expected to the simple Type XXIII hull. She was overhauled and commissioned on 1 October 1957 as Hecht - the German word for pike, a name appropriate to a small fast hunter. She served the new navy until 30 September 1968, when she was struck from the list and broken up at Kiel in 1969. Her career thus reads in two halves: 51 days as a Kriegsmarine boat that never saw combat, and eleven years as a Bundesmarine training submarine, learning the trade of postwar submarining for a country that had decided not to start any more wars.