U-995 Type VIIC/41 at theLaboe Naval Memorial. This U-boat is almost identical toU-997. | |
| History | |
|---|---|
| Name | U-997 |
| Ordered | 14 October 1941 |
| Builder | Blohm & Voss AG,Hamburg |
| Yard number | 197 |
| Laid down | 7 December 1942 |
| Launched | 18 August 1943 |
| Commissioned | 23 September 1943 |
| Fate |
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| General characteristics[1] | |
| Class & type | Type VIIC/41submarine |
| Displacement | |
| Length |
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| Beam |
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| Height | 9.60 m (31 ft 6 in) |
| Draught | 4.74 m (15 ft 7 in) |
| Installed power |
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| Propulsion |
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| Speed |
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| Range | |
| Test depth |
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| Complement | 44-52 officers & ratings |
| Armament |
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| Service record | |
| Part of: |
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| Identification codes: | M 55 164 |
| Commanders: |
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| Operations: |
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| Victories: | |
German submarineU-997 was aType VIIC/41U-boat built forNazi Germany'sKriegsmarine for service duringWorld War II.She waslaid down on 7 December 1942 byBlohm & Voss,Hamburg as yard number 197,launched on 18 August 1943 andcommissioned on 23 September 1943 underOberleutnant zur SeeHans Lehmann.
Like allType VIIC/41U-boats,U-977 had a displacement of 759 tonnes (747 long tons) when at the surface and 860 tonnes (850 long tons) while submerged. She had a total length of 67.10 m (220 ft 2 in), apressure hull length of 50.50 m (165 ft 8 in), a beam of 6.20 m (20 ft 4 in), and a draught of 4.74 m (15 ft 7 in).[3] The submarine was powered by twoGermaniawerft F46supercharged six-cylinder four-strokediesel engines producing a total of 2,800 to 3,200 metric horsepower (2,060 to 2,350 kW; 2,760 to 3,160 shp) and twoBBC GG UB 720/8double-acting electric motors producing a total of 750 metric horsepower (550 kW; 740 shp) for use while submerged. The boat was capable of operating at a depth of 250 metres (820 ft).[3]
The submarine had a maximum surface speed of 17.7 knots (32.8 km/h; 20.4 mph) and a submerged speed of 7.6 knots (14.1 km/h; 8.7 mph). When submerged, the boat could operate for 80 nautical miles (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 8,500 nautical miles (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph).[3]U-997 was fitted with three anti-aircraft guns, five 53.3 cm (21 in)torpedo tubes (four on the bow and one on the stern) and fourteentorpedoes. Itscomplement was between forty-four and sixty.[3]
U-997 was one of only ten Type VIIC's to be fitted with aBalkongerät (literally 'Balcony apparatus or equipment'). TheBalkongerät was used on U-boats (U-682,U-788,U-799,U-1021,U-1105,U-1172,U-1306,U-1307 andU-1308).[4] TheBalkongerät was standard on the Type XXI and theType XXIII. Nonetheless, it was also fitted to several Type IXs and oneType X. TheBalkongerät was an improved version ofGruppenhorchgerät (GHG) (group listening device). The GHG had 24 hydrophones, theBalkongerät had 48 hydrophones and improved electronics, which enabled more accurate readings to be taken.[5]
The boat's service career began on 23 September 1943 with the5th Training Flotilla, followed by 12 months active service, with a succession of three flotillas, namely9th Flotilla on 1 May 1944, then13th Flotilla on 1 June 1944, and finally with14th Flotilla on 1 March 1945.
U-997 took part in sevenwolfpacks, namely:
U-997 was surrendered on 9 May 1945 and was sunk by aircraft on 13 December 1945 in theNorth Atlantic, in position55°50′N10°05′W / 55.833°N 10.083°W /55.833; -10.083, as part ofOperation Deadlight.
| Date | Ship Name | Nationality | Tonnage[Note 1] | Fate[6] |
|---|---|---|---|---|
| 7 December 1944 | BO-229 | 105 | Sunk | |
| 22 April 1945 | Idefjord | 4,287 | Damaged | |
| 22 April 1945 | Onega | 1,603 | Sunk |