German submarine U-378 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II.
She carried out eight patrols before being sunk by US aircraft on 20 October 1943 in mid-Atlantic at position 47.6667°N -55°W.
She was a member of 16 wolfpacks.
She sank one warship.
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-378 had a displacement of 769t when at the surface and 871t while submerged. She had a total length of 67.1m (220.1feet), a pressure hull length of 50.5m (165.7feet), a beam of 6.2m (20.3feet), a height of 9.6m (31.5feet), and a draught of 4.74m (15.55feet). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of NaNPS for use while surfaced, two Garbe, Lahmeyer & Co. RP 137/c double-acting electric motors producing a total of 750PS for use while submerged. She had two shafts and two 1.23abbr=onNaNabbr=on propellers. The boat was capable of operating at depths of up to .
The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, the boat could operate for at ; when surfaced, she could travel at . U-378 was fitted with five 53.30NaN0 torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.82NaN2 SK C/35 naval gun, 220 rounds, and a 2sp=usNaNsp=us C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.
The submarine was laid down on 3 May 1940 at the Howaldtswerke yard at Kiel as yard number 9, launched on 13 September 1941 and commissioned on 30 October under the command of Kapitänleutnant Alfred Hoschatt.
The boat's first patrol was in two parts and commenced with her departure from Kiel on 11 March 1942. The second part began from the German island of Helgoland (sometimes spelt 'Heligoland'). She was attacked northeast of Norway's North Cape by the British destroyer . No damage was sustained.
U-378 continued to operate in northern waters such as the Barents, Greenland and Norwegian seas until April 1943 when her sphere of operations changed to the Atlantic Ocean.
This sortie saw the boat leave Trondheim on 12 April 1943, negotiate the gap separating Iceland and the Faroe Islands and sail as far westward as Newfoundland and Labrador. She then re-crossed the Atlantic, docking at La Pallice in occupied France on 4 June. At 54 days, this was easily the submarine's longest patrol.
U-378 sank the Polish destroyer on 8 October 1943. Her commander, ten officers, 166 ratings and seven British crew members were lost.
On 13 October, the boat was the target of a FIDO homing torpedo that had been dropped from a Grumman TBF Avenger, but the weapon missed.
The submarine was sunk by an Avenger / Wildcat pair on 20 October in mid-Atlantic from . Forty-eight men died in the depth charge attack; there were no survivors.
U-378 took part in 16 wolfpacks, namely: