German submarine U-317

History
Nazi Germany
Name:	U-317
Ordered:	14 October 1941
Builder:	Flender Werke, Lübeck
Yard number:	317
Laid down:	12 September 1942
Launched:	1 September 1943
Commissioned:	23 October 1943
Fate:	Sunk, 26 June 1944
General characteristics
Class & type:	Type VIIC/41 submarine
Displacement:	759 tonnes (747 long tons) surfaced 860 t (846 long tons) submerged
Length:	67.10 m (220 ft 2 in) o/a 50.50 m (165 ft 8 in) pressure hull
Beam:	6.20 m (20 ft 4 in) o/a 4.70 m (15 ft 5 in) pressure hull
Height:	9.60 m (31 ft 6 in)
Draught:	4.74 m (15 ft 7 in)
Installed power:	2,800–3,200 PS (2,100–2,400 kW; 2,800–3,200 bhp) (diesels) 750 PS (550 kW; 740 shp) (electric)
Propulsion:	2 shafts 2 × diesel engines 2 × electric motors
Speed:	17.7 knots (32.8 km/h; 20.4 mph) surfaced 7.6 knots (14.1 km/h; 8.7 mph) submerged
Range:	8,500 nmi (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph) surfaced 80 nmi (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth:	250 m (820 ft) Crush depth: 275–325 m (902–1,066 ft)
Complement:	4 officers, 40–56 enlisted
Armament:	5 × 53.3 cm (21 in) torpedo tubes (four bow, one stern) 14 × torpedoes 1 × 8.8 cm (3.46 in) deck gun (220 rounds) various AA guns
Service record
Part of:	4th U-boat Flotilla 23 October 1943 – 31 May 1944 9th U-boat Flotilla 1–26 June 1944
Commanders:	Oblt.z.S. Peter Rahlf 23 October 1943 – 26 June 1944
Operations:	1st patrol: 31 May – 2 June 1944 2nd patrol: 21–26 June 1944
Victories:	None

German submarine U-317 was a Type VIIC/41 U-boat of Nazi Germany's Kriegsmarine during World War II.

The submarine was laid down on 12 September 1942 at the Flender Werke at Lübeck, launched on 1 September 1943, and commissioned on 23 October 1943 under the command of Oberleutnant zur See Peter Rahlf.

Design

German Type VIIC/41 submarines were preceded by the heavier Type VIIC submarines. U-317 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), 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 Garbe, Lahmeyer & Co. RP 137/c 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-317 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 an anti-aircraft gun. The boat had a complement of between forty-four and sixty.

Service history

U-317 served with the 4th U-boat Flotilla for training, and later with the 9th U-boat Flotilla in front-line service from 1 to 26 June 1944.

U-317's first patrol took her from Kiel in Germany to Egersund in Norway, between 31 May and 2 June 1944. She then sailed from Egersund on 21 June for her second and final patrol.

U-317 was sunk with all hands on 26 June 1944, northeast of the Shetland islands, in position , by depth charges dropped by a Liberator anti-submarine bomber of No. 86 Squadron RAF.