Engineering:Type U 57 submarine

Short description: German World War I submarine class

Type U 57 was a class of U-boats built during World War I by the Kaiserliche Marine. Six Type U 57 were ordered at the beginning of the war and these were commissioned in 1916. A further six were ordered in 1915 and commissioned in 1917. Seven were lost during the war and the remaining five surrendered to the Allies and were scrapped.

Design

When World War I broke out on 28 July 1914, the German Navy initiated an emergencey war building program, the so-called mobilisation program. This mobilisation program called for the immediate construction of seventeen U-boats by the two submarine building shipyard in Germany: the Germaniawerft in Kiel and the Kaiserliche Werft Danzig. The Kaiserliche Werft received an order for five Type U 43 U-boats and the Germaniawerft would have received an order for the remaining twelve U-boats, but since this yard experienced serious delays in the delivery of the previous order of eleven Type U 31 U-boats, only six Type U 51 U-boats were ordered from Germaniawerft on 23 August 1914 and the remaining six were ordered as Type U 57 from a new yard AG Weser.

When in August 1915 AG Weser had capacity to build extra U-boats, six more Mobilisation U-boats - were ordered from AG Weser based on the same Type U 57 design.

Characteristics

The first three U 57s were fitted with two MAN six-cylinder two-stroke 8SS35 diesel engines with a total of 1,700 metric horsepower (1,250 kW; 1,677 bhp)t for use on the surface, the other nine Type U 57 U-boats were fitted with two more powerful S6V45/42 MAN diesel engines with a total of 2,400 metric horsepower (1,765 kW; 2,367 bhp). All Type U 57 had two Siemens-Schuckert double-acting electric motors with a total of 880 kW (1,196 PS; 1,180 shp) for underwater propulsion. These engines powered two shafts. Constructional diving depth was 50 m (164 ft 1 in).

All twelve Type U 57 U-boats were armed with four 50 cm (20 in) torpedo tubes, two fitted in the bow and two in the stern. U-57 - U-62 carried seven torpedoes and U-99 - U-104 carried ten to twelve torpedoes. Most boats received initially one or two 8.8 cm (3.5 in) SK L/30 deck guns. Some boats had one 8.8 cm deck gun replaced with a 10.5 cm (4.1 in) SK L/45 gun. The boats' complement was four officers and thirty-two enlisted men.

Differences in dimensions, speed, range and diesel engines

batch	U-57 - U-59	U-60 - U-62	U-99 - U-104
displacement surfaced	786 t (774 long tons)	768 t (756 long tons)	750 t (740 long tons)
displacement submerged	954 t (939 long tons)	956 t (941 long tons)	952 t (937 long tons)
Length	67.0 m (219.8 ft)	67.0 m (219.8 ft)	67.7 m (222 ft)
Beam	6.32 m (20.7 ft)
Draught	3.79 m (12.4 ft)	3.74 m (12.3 ft)	3.65 m (12.0 ft)
Height	8.05 m (26.4 ft)	8.05 m (26.4 ft)	8.25 m (27.1 ft)
length pressure hull	54.22 m (177 ft 11 in)	54.02 m (177 ft 3 in)	54.02 m (177 ft 3 in)
diameter pressure hull	4.05 m (13 ft 3 in)
speed surface	14.7 kn (27.2 km/h; 16.9 mph)	16.5 kn (30.6 km/h; 19.0 mph)	16.5 kn (30.6 km/h; 19.0 mph)
speed submerged	8.4 kn (15.6 km/h; 9.7 mph)	8.4 kn (15.6 km/h; 9.7 mph)	8.8 kn (16.3 km/h; 10.1 mph)
range surface at 8 knots	7,730–10,500 nmi (14,320–19,450 km; 8,900–12,080 mi)	8,600–11,400 nmi (15,900–21,100 km; 9,900–13,100 mi)	7,800–10,100 nmi (14,400–18,700 km; 9,000–11,600 mi)
range submerged at 5 knots	55 nmi (102 km; 63 mi)	49 nmi (91 km; 56 mi)	45.4 nmi (84.1 km; 52.2 mi)
diesel engines	8SS35 MAN	S6V45/42 MAN	S6V45/42 MAN

Ships

Name	Launched	Commissioned	Merchant ships sunk (nbr / GRT )	Fate
	29 April 1916	6 July 1916	55 / 91.680	Surrendered on 24 November 1918 and scrapped at Cherbourg in 1921
	31 May 1916	9 August 1916	21 / 30.901	Lost on 17 November 1917 in the Bristol Channel
	20 June 1916	7 September 1916	13 / 18.763	Lost on 14 May 1917 in the North Sea
	5 July 1916	1 November 1916	52 / 108.191	Surrendered on 21 November 1918 and scrapped in 1921
	22 July 1916	2 December 1916	34 / 84.861	Lost on 16 March 1918 in the Irish Sea
	2 August 1916	30 December 1916	46 / 123.252	Surrendered on 21 November 1918 and scrapped at Bo'ness in 1919-20
	27 January 1917	28 March 1917	none	Lost on 7 july 1917 in the North Sea
	25 February 1917	16 April 1917	8 / 27.625	Surrendered on 21 November 1918 and scrapped at Swansea in 1919-20
	1 April 1917	15 May 1917	24 / 29.813	Surrendered on 21 November 1918 and scrapped at Morecambe in 1920
	12 May 1917	18 June 1917	5 / 13.245	Lost in September 1918 in the North Sea
	9 June 1917	15 July 1917	7 / 15.481	Lost on 12 May 1918 in the English Channel
	3 June 1917	12 August 1917	7 / 10.493	Lost on 5 April 1918 in St George's Channel

Bibliography

• Gröner, Erich; Jung, Dieter; Maass, Martin (1991). German Warships 1815–1945, U-boats and Mine Warfare Vessels. 2. London: Conway Maritime Press. ISBN 0-85177-593-4. 
• Herzog, Bodo (1993) (in de). Deutsche U-Boote : 1906 - 1966. Erlangen: Müller. ISBN 9783860700365. 
• Miller, David (2002). The Illustrated Directory of Submarines of the World. St. Paul, Minnesota: MBI Pub. Co. ISBN 978-0-7603-1345-9. OCLC 50208951. 
• Möller, Eberhard; Brack, Werner (2004). The Encyclopedia of U-Boats. London: Chatham. ISBN 1-85367-623-3. https://naval-encyclopedia.com/docs/u-boats-from-1904-to-the-present-encyclopedia-of.pdf. 
• Rössler, Eberhard (1981). The U-boat: The evolution and technical history of German submarines. London: Cassell & Co. ISBN 0-304-36120-8.