German submarine U-394

German submarine U-394 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II.

She carried out two patrols. She did not sink or damage any ships.

She was sunk by a British aircraft and warships in the Norwegian Sea on 2 September 1944.

Design
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-394 had a displacement of 769 t when at the surface and 871 t while submerged. She had a total length of 67.10 m, a pressure hull length of 50.50 m, a beam of 6.20 m, a height of 9.60 m, and a draught of 4.74 m. The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2800 to 3200 PS for use while surfaced, two Garbe, Lahmeyer & Co. RP 137/c double-acting electric motors producing a total of 750 PS for use while submerged. She had two shafts and two 1.23 m propellers. The boat was capable of operating at depths of up to 230 m.

The submarine had a maximum surface speed of 17.7 kn and a maximum submerged speed of 7.6 kn. When submerged, the boat could operate for 80 nmi at 4 kn; when surfaced, she could travel 8500 nmi at 10 kn. U-394 was fitted with five 53.3 cm torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.8 cm SK C/35 naval gun, (220 rounds), one 3.7 cm Flak M42 and two twin 2 cm C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.

Service history
The submarine was laid down on 31 January 1941 at the Howaldtswerke (yard) at Flensburg as yard number 26, launched on 19 June 1943 and commissioned on 7 August under the command of Oberleutnant zur See Ernst-Günther Unterhorst.

The boat was a member of two wolfpacks.

She served with the 5th U-boat Flotilla from 7 August 1943 and the 1st flotilla from 1 April 1944. She was reassigned to the 11th flotilla on 1 June.

Her first patrol was preceded by a series of short journey from Kiel in Germany to Arendal (northeast of Kristiansand), Bergen and Narvik in Norway.

First patrol
The boat departed Narvik on 1 June 1944. She was soon sweeping the Norwegian Sea between Jan Mayen island and the Norwegian mainland. She arrived at Hammerfest on 8 July.

Second patrol and loss
U-394 left Hammerfest on 27 July 1944. She patrolled the Greenland and Barents seas. On 2 September, southeast of Jan Mayen, she was sunk by rockets and depth charges from a Fairey Swordfish of 825 Naval Air Squadron (this aircraft was from the escort carrier HMS Vindex (D15)), the British destroyers HMS Keppel (D84) and HMS Whitehall (D94). The sloops HMS Mermaid (U30) and HMS Peacock (U96) were also involved.

50 men died in the U-boat; there were no survivors.

Wolfpacks
U-394 took part in two wolfpacks, namely:
 * Trutz (2 June – 6 July 1944)
 * Trutz (17 August – 2 September 1944)