# German submarine U-665

German submarine U-665 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II. She was laid down on 10 June 1941 by Deutsche Werft, Hamburg as yard number 814, launched on 9 June 1942 and commissioned on 22 July 1942 under Leutnant zur See Hans-Jürgen Haupt.

## Design

German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-665 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 Siemens-Schuckert GU 343/38–8 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-665 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 two twin 2 cm (0.79 in) C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.

## Service history

The boat's career began with training at 5th U-boat Flotilla on 22 July 1942, followed by active service on 1 February 1943 as part of the 1st Flotilla for the remainder of her short service. In her sole patrol she sank one merchant ship, for a total of 7,134 gross register tons (GRT).

### Wolfpacks

U-665 took part in three wolfpacks, namely:
* Neuland (4 – 6 March 1943)
* Ostmark (6 – 11 March 1943)
* Stürmer (11 – 20 March 1943)

### Fate

U-665 has been missing since 22 March 1943 in the Bay of Biscay, west of La Pallice.

### Previously recorded fate

U-665 was thought to have been sunk on 22 March 1943 in the Bay of Biscay west of Nantes at 46°47′N 09°58′W﻿ / ﻿46.783°N 9.967°W﻿ / 46.783; -9.967, by depth charges from Vickers Wellington aircraft of No. 172 Squadron RAF (call-sign G). This attack was actually against U-448, inflicting no damage.
U-665 was also thought to have been sunk on 22 March 1943 in the North Atlantic at 48°04′N 10°26′W﻿ / ﻿48.067°N 10.433°W﻿ / 48.067; -10.433, by depth charges from an Armstrong Whitworth Whitley VII of No. 10 Operational Training Unit RAF (10 OTU) (call-sign Q), for the loss of all hands.

## Summary of raiding history

| Date | Ship Name | Nationality | Tonnage (GRT) | Fate |
| 17 March 1943 | Fort Cedar Lake | United Kingdom | 7,134 | Sunk |