were preceded by the shorter Type VIIB submarines. U-564 had a displacement of when at the surface and while submerged. She had a total length of, a pressure hull length of, a beam of, a height of, and a draught of. The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of for use while surfaced, two Brown, Boveri & Cie GG UB 720/8 double-acting electric motors producing a total of for use while submerged. She had two shafts and two 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-564 was fitted with five torpedo tubes, fourteen torpedoes, one SK C/35 naval gun, 220 rounds, and a C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.
Service history
Early patrols
Her first patrol took U-564 from Kiel to Brest in occupied France, spending a total of 41 days at sea. The patrol brought a number of successes; on 27 June Suhren came across convoy HX 133. He damaged the Norwegian tanker and sank the Dutch and the British that day. He had one further success on that patrol, sinking the Icelandic merchantman on 29 June. U-564 put into Brest on 27 July, having sunk three merchant ships for, and damaged another for 9,467 tons. She sailed again from Brest on 16 August, heading into the Atlantic. She came across convoy OG-71 and sank the Irish and the British tugEmpire Oak on 22 August. She sank an escort the following day,. U-564 returned to Brest on 27 August after 12 days at sea, having sunk three ships for. She sailed again on 16 September, this time encountering convoy HG-75 on 24 October. She sank three British merchantmen that day,, and. U-564 was attacked later in the evening, by a bomb from an aircraft and later by an escort with depth charges. She escaped damage however, and returned to port at Lorient on 1 November having spent 47 days at sea and sunk three ships for 2,587 tons. U-564 relocated to La Pallice in early 1942, and sailed from there on 18 January. She sank the Canadian tanker northwest of Bermuda on 11 February 1942, and damaged the British tanker, although not severely, on 16 February, before returning to Brest on 6 March, after 48 days on patrol with sunk and damaged.
Off the American coast
U-564 sailed from Brest on 4 April 1942, to cross the Atlantic and prey on shipping off the North American coast, including Florida. She was in position in early May and on 3 May, secured her first success, sinking the British. On the 4 May, she damaged the British, and on 5 May she damaged the American. On 8 May she sank the American merchantman, the following day she sank the Panamanian tanker. Her final success in American waters was to sink the Mexican tanker. U-564 arrived back in Brest on 6 June, having spent 64 days at sea and sunk four ships, for, and damaged two ships, for. U-564 repeated the exercise on her next patrol, departing Brest on 6 July to operate off the coast of South America. Whilst outward-bound across the Atlantic, Suhren came across convoy OS-34 near the Azores, and on 19 July sank the British merchant, and damaged the . Operating off the northern South America coast, he sank the and the west of Grenada on 19 August and on the 30th, she sank the Norwegian tanker Vardaas north of Scarborough. U-564 arrived back in Brest on 18 September after 72 days on patrol, having sunk five ships for.
Fiedler takes charge
This was Suhren's last patrol as commander of U-564. He left on 1 October to become an instructor, Oberleutnant zur See Hans Fiedler took command. He took the boat on two war patrols in 1943 but failed to hit any enemy ships. On one of these sorties events took a dramatic turn when the U-boat lost a crewman, Fähnrich zur See Heinrich Fuerhake. U-564 was transferred to operate out of Bordeaux in April 1943. She left the French port city for the final time on 9 June with four other outbound U-boats,,, and. A Royal Air ForceShort Sunderland spotted the boats and attacked them off Cape Finisterre at 18.59 hours on 13 June. The aircraft targeted U-564 and dropped its bombs, but was shot down by anti-aircraft fire, killing all 11 of the crew. U-564 had sustained heavy damage and turned back, escorted by U-185.
An Armstrong Whitworth Whitley sighted the two U-boats in the Bay of Biscay the following day and shadowed them. U-564 was unable to dive due to the damage already sustained. By 16.45 hours the Whitley was running low on fuel and attacked U-564. The two U-boats damaged their attacker with anti-aircraft fire but the aircraft's depth charges fatally damaged U-564 and she sank at 17:30 hours. The damaged Whitley was forced to ditch, where a French trawler rescued the crew. There were 18 survivors from U-564 including the commander. picked them up and transferred them to the two hours later.
