German submarine U-128 (1941)

German submarine U-128 was a Type IXC U-boat of Nazi Germany's Kriegsmarine during World War II. She was sunk 17 May 1943, by American action.

Design
German Type IXC submarines were slightly larger than the original Type IXBs. U-128 had a displacement of 1120 t when at the surface and 1232 t while submerged. The U-boat had a total length of 76.76 m, a pressure hull length of 58.75 m, a beam of 6.76 m, a height of 9.60 m, and a draught of 4.70 m. The submarine was powered by two MAN M 9 V 40/46 supercharged four-stroke, nine-cylinder diesel engines producing a total of 4400 PS for use while surfaced, two Siemens-Schuckert 2 GU 345/34 double-acting electric motors producing a total of 1000 PS for use while submerged. She had two shafts and two 1.92 m propellers. The boat was capable of operating at depths of up to 230 m.

The submarine had a maximum surface speed of 18.3 kn and a maximum submerged speed of 7.3 kn. When submerged, the boat could operate for 63 nmi at 4 kn; when surfaced, she could travel 13450 nmi at 10 kn. U-128 was fitted with six 53.3 cm torpedo tubes (four fitted at the bow and two at the stern), 22 torpedoes, one 10.5 cm SK C/32 naval gun, 180 rounds, and a 3.7 cm SK C/30 as well as a 2 cm C/30 anti-aircraft gun. The boat had a complement of forty-eight.

Service history
Ordered on 7 August 1939 from DeSchiMAG AG Weser in Bremen, U-128 was laid down on 10 July 1940, launched on 20 February 1941 and commissioned by Kapitänleutnant Ulrich Heyse on 12 May 1941.

The boat was a training vessel in the second flotilla until 30 November 1941 based in Wilhelmshaven. She was then based in Lorient.

During her six completed war patrols, U-128 sank 12 ships, for a total of 83,639 tons. On 1 March 1943 command was transferred to Kptlt. Hermann Steinert, who commanded her until her loss a few months later.

Fate
On 17 May 1943, while operating in the South Atlantic near Pernambuco, two Mariner flying boats, PBM 74-P5 and PBM-74-P6 of the US Navy Patrol Squadron VP-74, made U-128 surface with depth charges. Two US Navy destroyers (USS Jouett (DD-396) and USS Moffett (DD-362)) also hit her with 5-inch gunfire. The crew opened the submarine's seacocks as they abandoned ship, scuttling the submarine. The final toll was seven dead but there were 47 survivors.