# German submarine U-624

German submarine U-624 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II. She was laid down on 15 July 1941 by Blohm & Voss in Hamburg as yard number 600, launched on 31 March 1942 and commissioned on 28 May 1942 under Kapitänleutnant Ulrich Graf von Soden-Fraunhofen.

## Design

German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-624 had a displacement of 769 tonnes (757 long tons) when at the surface and 871 tonnes (857 long tons) while submerged. She had a total length of 67.10 m (220 ft 2 in), a pressure hull length of 50.50 m (165 ft 8 in), a beam of 6.20 m (20 ft 4 in), a height of 9.60 m (31 ft 6 in), and a draught of 4.74 m (15 ft 7 in). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2,800 to 3,200 metric horsepower (2,060 to 2,350 kW; 2,760 to 3,160 shp) for use while surfaced, two Brown, Boveri & Cie GG UB 720/8 double-acting electric motors producing a total of 750 metric horsepower (550 kW; 740 shp) for use while submerged. She had two shafts and two 1.23 m (4 ft) propellers. The boat was capable of operating at depths of up to 230 metres (750 ft).
The submarine had a maximum surface speed of 17.7 knots (32.8 km/h; 20.4 mph) and a maximum 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). U-624 was fitted with five 53.3 cm (21 in) torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.8 cm (3.46 in) SK C/35 naval gun, 220 rounds, and a 2 cm (0.79 in) C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.

## Service history

The boat's service began on 28 May 1942 with training as part of the 8th U-boat Flotilla. She was transferred to the 7th Flotilla, operating out of St.Nazaire, on 1 October 1942 for active service in the North Atlantic .
In just two patrols she sank five merchant ships and three warships for a total of 39,855 gross register tons (GRT) and 873 tons, plus one merchant ship damaged.

### Fate

U-624 was sunk on 7 February 1943 in the North Atlantic in position 55°42′N 26°17′W﻿ / ﻿55.700°N 26.283°W﻿ / 55.700; -26.283. She was caught unawares on the surface whilst transmitting to base a lengthy report of the previous night's action around Convoy SC 118. A RAF B-17 Flying Fortress aircraft of (Sqdn. 220/J), operating out of Londonderry Port, depth charged her 55 nautical miles (102 km; 63 mi) astern of the convoy. All 45 hands were lost.

### Wolfpacks

U-624 took part in five wolfpacks, namely:
* Puma (23 – 29 October 1942)
* Natter (30 October – 8 November 1942)
* Kreuzotter (8 – 24 November 1942)
* Habicht (10 – 19 January 1943)
* Haudegen (19 January – 7 February 1943)

## Summary of raiding history

| Date | Ship Name | Nationality | Tonnage | Fate |
| 29 October 1942 | Kosmos II | Norway | 16,966 | Sunk |
| 29 October 1942 | HMS LCT-2190 | Royal Navy | 291 | Sunk |
| 29 October 1942 | HMS LCT-2192 | Royal Navy | 291 | Sunk |
| 29 October 1942 | HMS LCT-2284 | Royal Navy | 291 | Sunk |
| 29 October 1942 | Pan-New York | United States | 7,701 | Sunk |
| 18 November 1942 | President Sergent | United Kingdom | 5,344 | Sunk |
| 18 November 1942 | Parismina | United States | 4,732 | Sunk |
| 18 November 1942 | Yaka | United States | 5,432 | Damaged |
| 25 January 1943 | Lackenby | United Kingdom | 5,112 | Sunk |