German submarine U-457 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II.
She carried out three patrols, on which she sank two ships and damaged one more.
She was sunk northeast of the North Cape by a British warship on 16 September 1942.
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-457 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 Siemens-Schuckert GU 343/38–8 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-457 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 26 October 1940 in the Deutsche Werke, Kiel as yard number 288, launched on 4 October 1941 and commissioned on 5 November under the command of Korvettenkapitän Karl Brandenburg.
She served with the 6th U-boat Flotilla from 5 November 1941 for training and the 11th flotilla from 1 July 1942 for operations.
U-457s first patrol was preceded by two short journeys from Kiel to Trondheim in Norway. The patrol itself commenced with her departure from Trondheim on 28 June 1942.
She sank the Christopher Newport east of Bear Island on 4 July. The ship, from the ill-fated convoy PQ 17, had already been hit by an aerial torpedo in the Barents Sea. A 'coup de grace' torpedo from the British submarine P-614 failed to sink the ship; but one from U-457 succeeded.
The boat then went on to sink the RFA Aldersdale on 7 July 1942; after the merchantman, also a member of PQ 17, had been bombed. U-457 came across the abandoned tanker and after firing 75 rounds from her deck gun, finished the wreck off with a single torpedo.
Her second foray was relatively uneventful – starting in Narvik on 8 August 1942 and finishing in Trondheim on 7 September.
The submarine damaged the Atheltemplar of the Convoy PQ 18 on 14 September 1942 south of Spitsbergen (Svalbard). U-457 was sunk on the 16th by depth charges from the British destroyer .
Forty-five men died in U-457; there were no survivors.
U-457 took part in two wolfpacks, namely:
| Date | Ship Name | Nationality | Tonnage[1] | Fate[2] | |
|---|---|---|---|---|---|
| 4 July 1942 | Christopher Newport |  United States | 7,191 | Sunk | |
| 7 July 1942 | RFA Aldersdale | Royal Fleet Auxiliary | 8,402 | Sunk | |
| 14 September 1942 | Atheltemplar |  | 8,939 | Damaged |