German submarine U-107 (1940)

For other ships with the same name, see German submarine U-107.

U-107 at Lorient in November 1941
History
Nazi Germany
Name:	U-107
Ordered:	24 May 1938
Builder:	DeSchiMAG AG Weser, Bremen
Yard number:	970
Laid down:	6 December 1939
Launched:	2 July 1940
Commissioned:	8 October 1940
Homeport:	Lorient, France
Fate:	Sunk, 18 August 1944
General characteristics
Class & type:	Type IXB U-boat
Displacement:	1,051 t (1,034 long tons) surfaced 1,178 t (1,159 long tons) submerged
Length:	76.50 m (251 ft) o/a 58.75 m (192 ft 9 in) pressure hull
Beam:	6.76 m (22 ft 2 in) o/a 4.40 m (14 ft 5 in) pressure hull
Draught:	4.70 m (15 ft 5 in)
Installed power:	4,400 PS (3,200 kW; 4,300 bhp) (diesels) 1,000 PS (740 kW; 990 shp) (electric)
Propulsion:	2 shafts 2 × diesel engines 2 × electric motors
Range:	12,000 nmi (22,000 km; 14,000 mi) at 10 knots (19 km/h; 12 mph) surfaced 64 nmi (119 km; 74 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth:	230 m (750 ft)
Complement:	48 to 56 officers and ratings
Armament:	6 × torpedo tubes (4 bow, 2 stern) 22 × 53.3 cm (21 in) torpedoes 1 × 10.5 cm SK C/32 naval gun (180 rounds) 1 × 3.7 cm (1.5 in) AA gun 1 × twin 2 cm FlaK 30 AA guns
Service record
Part of:	Kriegsmarine: 2nd U-boat Flotilla
Commanders:	K.Kapt. Günther Hessler October 1940 – December 1941 Kptlt. Harald Gelhaus December 1941 – June 1943 Kptlt. Volker Simmermacher July 1943 – August 1944 Lt.z.S. Karl-Heinz Fritz August 1944
Operations:	16 patrols
Victories:	37 ships sunk for a total of 207,375 GRT Two auxiliary warships sunk for a total of 10,411 GRT Three ships damaged for a total of 17,392 GRT One auxiliary warship (USS Rapidan) of 8,246 GRT damaged

German submarine U-107 was a Type IXB U-boat of Nazi Germany's Kriegsmarine that operated during World War II. Between January 1941 and August 1944, it sailed on 16 active patrols at a time when a U-boat averaged a lifespan of seven to 10 patrols. During that time, U-107 sank 39 Allied ships, in addition to damaging another four ships. It was launched on 2 July 1940, based at the U-boat port of Lorient, with a crew of 53 under the initial command of Günther Hessler. It was later commanded, in order, by Harald Gelhaus, Valker Simmermacher and its final commander, Karl Heinz Fritz.

Design

German Type IXB submarines were slightly larger than the original German Type IX submarines, later designated IXA. U-107 had a displacement of 1,051 tonnes (1,034 long tons) when at the surface and 1,178 tonnes (1,159 long tons) while submerged. The U-boat had a total length of 76.50 m (251 ft), a pressure hull length of 58.75 m (192 ft 9 in), a beam of 6.76 m (22 ft 2 in), a height of 9.60 m (31 ft 6 in), and a draught of 4.70 m (15 ft 5 in). The submarine was powered by two MAN M 9 V 40/46 supercharged four-stroke, nine-cylinder diesel engines producing a total of 4,400 metric horsepower (3,240 kW; 4,340 shp) for use while surfaced, two Siemens-Schuckert 2 GU 345/34 double-acting electric motors producing a total of 1,000 metric horsepower (740 kW; 990 shp) for use while submerged. She had two shafts and two 1.92 m (6 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 18.2 knots (33.7 km/h; 20.9 mph) and a maximum submerged speed of 7.3 knots (13.5 km/h; 8.4 mph). When submerged, the boat could operate for 64 nautical miles (119 km; 74 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 12,000 nautical miles (22,000 km; 14,000 mi) at 10 knots (19 km/h; 12 mph). U-107 was fitted with six 53.3 cm (21 in) torpedo tubes (four fitted at the bow and two at the stern), 22 torpedoes, one 10.5 cm (4.13 in) SK C/32 naval gun, 180 rounds, and a 3.7 cm (1.5 in) as well as a 2 cm (0.79 in) anti-aircraft gun. The boat had a complement of forty-eight.

Service history

First patrol

Date	Name	Flag	Tonnage (GRT)	Convoy	Position
3 February 1941	Empire Citizen	UK	4,683	Convoy OB 279
3 February 1941	Crispin	Royal Navy	5,051	Convoy OB 279
6 February 1941	Maplecourt	Canada	3,388	Convoy SC 20
23 February 1941	SS Manistee	Royal Navy	5,360	Convoy OB 288

Second patrol and most successful period

Date	Name	Flag	Tonnage (GRT)	Convoy	Position
8 April 1941	Helena Margareta	UK	3,316	Convoy OG 57
8 April 1941	Eskdene	UK	3,829	Convoy OG 57
9 April 1941	Harpathian	UK	4,671	Convoy OG 57
9 April 1941	Duffield	UK	8,516	Convoy OG 57
21 April 1941	Calchas	UK	10,305
30 April 1941	Lassell	UK	7,417	Convoy OB 309
17 May 1941	Marisa	Netherlands	8,029
18 May 1941	Piako	UK	8,286
27 May 1941	Colonial	UK	5,108	Convoy OB 318
28 May 1941	Papalemos	Greece	3,748
31 May 1941	Sire	UK	5,664
1 June 1941	Alfred Jones	UK	5,013	Convoy OB 320
8 June 1941	Adda	UK	7,816	Convoy OB 323
13 June 1941	Pandias	Greece	4,981

Third patrol

Date	Name	Flag	Tonnage (GRT)	Convoy	Position
24 September 1941	Dixcove	UK	3,790	Convoy SL 87
24 September 1941	Lafian	UK	4,876	Convoy SL 87
24 September 1941	John Holt	UK	4,975	Convoy SL 87

Fifth patrol

Date	Name	Flag	Tonnage (GRT)	Convoy	Position
31 January 1942	San Arcadio	UK	7,419
6 February 1942	Major Wheeler	USA	3,431		E of Cape Hatteras
21 February 1942	Egda	Norway	10,068	Convoy ON 65	Damaged

Sixth patrol

File:Bundesarchiv Bild 101II-MW-4284-30A, Südatlantik, U-107 mit Versorgungsschiff.jpg

U-107 meets a supply ship in the South Atlantic

Date	Name	Flag	Tonnage (GRT)	Convoy	Position
29 May 1942	Western Head	UK	2,599
1 June 1942	Bushranger	Panama	4,536
7 June 1942	Castilla	Honduras	3,910
8 June 1942	Suwied	USA	3,249
10 June 1942	Merrimack	USA	2,606
19 June 1942	Cheerio	USA	35
26 June 1942	Jagersfontein	Netherlands	10,083

Eighth patrol

Date	Name	Flag	Tonnage (GRT)	Convoy	Position
3 September 1942	Hollinside	UK	4,172
3 September 1942	Penrose	UK	4,393
7 October 1942	Andalucia Star	UK	14,943

Ninth patrol

• 4 March 1943, came under attack from an unidentified Allied aircraft.

Moderately damaged by the attack.

• 22 March 1943 at 14:35 it came under attack from another unidentified Allied aircraft

Undamaged

Date	Name	Flag	Tonnage (GRT)	Convoy	Position
22 February 1943	Roxborough Castle	UK	7,801
13 March 1943	Oporto	UK	2,352	Convoy OS 44
13 March 1943	Marcella	UK	4,592	Convoy OS 44
13 March 1943	Sembilangan	Netherlands	4,990	Convoy OS 44
13 March 1943	SS Clan Alpine	UK	5,442	Convoy OS 44

Tenth patrol

Date	Name	Flag	Tonnage (GRT)	Convoy	Position
1 May 1943	Port Victor	UK	12,411

Eleventh patrol

Date	Name	Flag	Tonnage (GRT)	Convoy	Position
28 August 1943	Albert Gallatin	USA	7,176		Off Savannah, Georgia Damaged
11 September 1943	USS Rapidan	US Navy	8,246	Convoy NG 385	Damaged

Fifteenth patrol

Date	Name	Flag	Tonnage (GRT)	Convoy	Position
13 June 1944	Lark	USA	148		Damaged

Sixteenth and final patrol

• On 16 August 1944, U-107 departed Lorient on a transport run to La Pallice. It was intercepted on 18 August in the Bay of Biscay, west of La Rochelle, in position , by Allied forces, and was sunk by depth charges from Short Sunderland EJ150 (coded NS-W) of No. 201 Squadron, Royal Air Force. All 58 hands were lost.

Wolfpacks

U-107 took part in 15 wolfpacks, namely.

• Störtebecker (5–7 November 1941)
• Seeräuber (14–23 December 1941)
• Blücher (23–28 August 1942)
• Iltis (6–23 September 1942)
• Hartherz (3–7 February 1943)
• Delphin (11–14 February 1943)
• Robbe (16 February – 13 March 1943)
• Amsel 2 (4–6 May 1943)
• Elbe (7–10 May 1943)
• Elbe 2 (10–14 May 1943)
• Weddigen (24 November – 7 December 1943)
• Coronel (7–8 December 1943)
• Coronel 2 (8–14 December 1943)
• Coronel 3 (14–17 December 1943)
• Borkum (18–30 December 1943)