German submarine U-616

German submarine U-616 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II. She was laid down on 20 May 1941 by Blohm & Voss, Hamburg as yard number 592, launched on 8 February 1942 and commissioned on 2 April 1942 under Oberleutnant zur See (Oblt.z.S.) Johann Spindlegger.

On 8 October 1943, Spindlegger was replaced by Oblt.z.S. Siegfried Koitschka, who commanded her until she was sunk in 1944.

Design
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-616 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 Brown, Boveri & Cie GG UB 720/8 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-616 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, and an anti-aircraft gun. The boat had a complement of between forty-four and sixty.

Service history
The boat's career began with training at 8th U-boat Flotilla on 2 April 1942, followed by active service on 1 January 1943 as part of the 6th Flotilla. On 1 June 1943 she transferred to operations in the Mediterranean as part of 29th Flotilla until her sinking in 1944.

In 9 patrols she sank 2 warships and damaged 2 merchant ships, for a total of 2,181 tons and, respectively.

Wolfpacks
U-616 took part in two wolfpacks, namely
 * Burggraf (24 February – 5 March 1943)
 * Westmark (6–11 March 1943)
 * Stürmer (11–20 March 1943)

Fate
U-616 was sunk on 17 May 1944 in the Mediterranean in position 36.76667°N, 0.86667°W, by depth charges from USS Nields (DD-616), USS Gleaves (DD-423), USS Ellyson (DD-454), USS Macomb (DD-458), USS Hambleton (DD-455), USS Rodman (DD-456), USS Emmons (DD-457) and a RAF Wellington bomber of 36 Squadron