German submarine U-1023 was a Type VIIC/41 U-boat of Nazi Germany's Kriegsmarine. She was laid down on 20 May 1943 by Blohm & Voss in Hamburg, Germany, and commissioned on 15 June 1944 with Oberleutnant Wolfgang Strenger in command. U-1023 sank one ship and damaged one more for a total of and 335 tons. After the war she was sunk in Operation Deadlight.
German Type VIIC/41 submarines were preceded by the heavier Type VIIC submarines. U-1023 had a displacement of 759t when at the surface and 860t while submerged. She had a total length of 67.1m (220.1feet), a pressure hull length of 50.5m (165.7feet), a beam of 6.2m (20.3feet), a height of 9.6m (31.5feet), and a draught of 4.74m (15.55feet). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of NaNPS for use while surfaced, two Brown, Boveri & Cie GG UB 720/8 double-acting electric motors producing a total of 750PS for use while submerged. She had two shafts and two 1.23abbr=onNaNabbr=on propellers. The boat was capable of operating at depths of up to .
The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, the boat could operate for at ; when surfaced, she could travel at . U-1023 was fitted with five 53.30NaN0 torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.82NaN2 SK C/35 naval gun, (220 rounds), one 3.7cm (01.5inches) Flak M42 and two 2sp=usNaNsp=us C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.
U-1023 was mounted with a single 3.7 cm Flakzwilling M43U gun on the rare LM 43U mount. The LM 43U mount was the final design of mount used on U-boats and is only known to be installed on U-boats (and). The 3.7 cm Flak M42U was the marine version of the 3.7 cm Flak used by the Kriegsmarine on Type VII and Type IX U-boats. U-1023 was mounted with two 2cm Flak C38 in a M 43U Zwilling mount with short folding shield on the upper Wintergarten.[1] The M 43U mount was used on a number of U-boats (and).
U-1023 was ordered by the Kriegsmarine on 13 June 1942. She was laid down about one year later at Blohm & Voss, Hamburg on 20 May 1943. Almost a year later, U-1023 was launched from Hamburg on 3 May 1944. She was formally commissioned later that year on 15 June. U-1023 carried 5 × 53.30NaN0 torpedo tubes (4 located in the bow, 1 in the stern) and had one 8.82NaN2 deck gun with 220 rounds. She could also carry 14 G7e torpedoes or 26 TMA mines and had a crew of 44–52 men. She was one of the U-boats that used the Schnorchel underwater breathing apparatus.[2]
After her redesignation as a front-line U-boat, U-1023 left port on her first and only patrol. By that time, she had moved from Kiel to her later location in Bergen via a stopover in Horten Naval Base. After leaving on 25 March 1945 for her first patrol, U-1023 intercepted and attacked Riverton, a British steam merchant on 23 April. She was damaged and beached off St. Ives Bay. Later, on 7 May 1945, the last day of the war in Europe, U-1023 found the 335 tons Norwegian minesweeper, which was sunk with 22 dead.
U-1023 was surrendered at Weymouth, England on 10 May 1945.[3] After the war she was paraded up the west coast of the UK visiting a number of ports including Plymouth, Brixham, Falmouth, Bristol, Swansea, Liverpool, Holyhead, Manchester, Fleetwood, Belfast, Glasgow, Greenock, Rothsay, Oban. Several hundred thousand visitors were given a tour of the boat during this time.[4] U-1023 was then used in Operation Deadlight and sunk by the Allies on 7 January 1946.[2]
| Date | Ship Name | Nationality | Tonnage[5] | Fate[6] | |
|---|---|---|---|---|---|
| 23 April 1945 | Riverton |  United Kingdom | 7,345 | Damaged | |
| 7 May 1945 | HNoMS NYMS-382 | 335 | Sunk |