Type XIV submarine

German Type XIV submarines were shortened and deepened versions of the Type IXDs. The boats had a displacement of 1,688 tonnes (1,661 long tons) when at the surface and 1,932 tonnes (1,901 long tons) while submerged.[1] The U-boats had a total length of 67.10 m (220 ft 2 in), a pressure hull length of 48.51 m (159 ft 2 in), a beam of 9.35 m (30 ft 8 in), a height of 11.70 m (38 ft 5 in), and a draught of 6.51 m (21 ft 4 in). The submarines were powered by two Germaniawerft supercharged four-stroke, six-cylinder diesel engines producing a total of 2,800–3,200 metric horsepower (2,060–2,350 kW; 2,760–3,160 shp) for use while surfaced, two Siemens-Schuckert 2 GU 345/38-8 double-acting electric motors producing a total of 750 metric horsepower (550 kW; 740 shp) for use while submerged. They had two shafts and two propellers. The boats were capable of operating at depths of up to 240 metres (790 ft).[1]

The submarines had a maximum surface speed of 14.4–14.9 knots (26.7–27.6 km/h; 16.6–17.1 mph) and a maximum submerged speed of 6.2 knots (11.5 km/h; 7.1 mph).[1] When submerged, the boats could operate for 120 nautical miles (220 km; 140 mi) at 2 knots (3.7 km/h; 2.3 mph); when surfaced, they could travel 12,350 nautical miles (22,870 km; 14,210 mi) at 10 knots (19 km/h; 12 mph). The boats were not fitted with torpedo tubes or deck guns, but had two 3.7 cm (1.5 in) SK C/30 anti-aircraft guns with 2500 rounds as well as a 2 cm (0.79 in) C/30 gun with 3000 rounds. The boats had a complement of fifty-three.[1]

Due to its large size, the Type XIV could resupply other boats with 613 t (603 long tons) of fuel, 13 t (13 long tons) of motor oil, four torpedoes,[2] and fresh food that was preserved in refrigerator units. In addition, the boats were equipped with bakeries in order to provide the luxury of fresh bread for crews being resupplied. The Type XIV also had a doctor and medical facility for injured sailors, and even had a two-man brig to imprison sailors awaiting discipline back at home. Cargo was transported by means of a 20-foot inflatable boat and portable cranes. The flat main deck with cargo hatches and davits was designed in theory to facilitate the transfer of bulk supplies, however its low freeboard made this work extremely hazardous in typical North Atlantic swells that made the deck awash, so often supplies had to be hand-lifted through the smaller but dryer conning tower hatches to avoid flooding the boat. Resupply and refueling operations often took hours, putting both the milk cow and the submarine it was servicing at risk.[3]

If the Germans came under Allied attack during a resupply operation, the milk cow would dive first while the other submarine might fight it out on the surface for a while, as the Type XIV's bulk and flat deck made it slower to maneuver and submerge.[3] The Type XIV had no torpedo tubes or deck guns, only defensive armament of anti-aircraft guns.[1]

The milk cows operated 300–400 miles off the North American mainland which was the so-called mid-Atlantic gap, far enough from Allied anti-submarine patrols and aircraft while still close enough to provide logistical support to U-boats.[3] In 1942, the milk cows enabled Type VIIC boats to remain on station for a couple more weeks off of the American coast during the "Second Happy Time" raids of the Battle of the Atlantic.

The milk cows were priority targets for Allied forces, as sinking one milk cow would effectively curtail the operations of several regular U-boats and force them to return home for supplies. Ultra intercepts provided information concerning sailing and routing, and this, coupled with improved Allied radar and air coverage in the North Atlantic, eliminated most of them during 1943 including 4 lost in the month of July alone. By the end of the war all ten had been sunk. Milk cow duty was especially hazardous; 289 sailors were killed out of an estimated complement of 530–576 men.

Ten boats of this type were commissioned:[1]

• U-459, commissioned 15 November 1941, scuttled 24 July 1943
• U-460, commissioned 24 December 1941, sunk 4 October 1943
• U-461, commissioned 30 January 1942, sunk 30 July 1943
• U-462, commissioned 5 March 1942, sunk 30 July 1943
• U-463, commissioned 2 April 1942, sunk 15 May 1943
• U-464, commissioned 30 April 1942, scuttled 20 August 1942
• U-487, commissioned 21 December 1942, sunk 13 July 1943
• U-488, commissioned 1 February 1943, sunk 26 April 1944
• U-489, commissioned 8 March 1943, sunk 4 August 1943
• U-490, commissioned 27 March 1943, sunk 12 June 1944[1]

Fourteen planned Type XIVs were cancelled. Three of them (U-491, U-492, U-493) were about 75% complete when work was stopped in 1944. The other eleven boats had not been laid down when they were cancelled on 27 May 1944. On that same day Karl Dönitz stopped construction on the Type XX U-boats, large transport boats that would not have been ready until mid-1945.[1]

• Gröner, Erich; Jung, Dieter; Maass, Martin (1991). U-boats and mine warfare vessels. German Warships 1815–1945. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN 0-85177-593-4.
• Neistlé, Axel (2014). German U-Boat Losses during World War II: Details of Destruction (2 ed.). Havertown: Frontline Books (published 30 June 2014).

• Helgason, Guðmundur. "The Milkcows". German U-boats of WWII - uboat.net. Retrieved 20 April 2015.
• Helgason, Guðmundur. "Type XIV Milch Cows (supply boats)". German U-boats of WWII - uboat.net. Retrieved 20 April 2015.