Cruiser submarine

Surcouf had the largest guns of any cruiser submarine.

A cruiser submarine was a very large submarine designed to remain at sea for extended periods in areas distant from base facilities. Their role was analogous to surface cruisers; 'cruising' distant waters, commerce raiding, and otherwise operating independently. When operating within a fleet, cruisers and cruiser submarines could be expected to scout for and screen the battle fleet. Cruiser submarines were successful for a brief period of World War I, but were less successful than smaller submarines during World War II. Large submarines remained vulnerable to damage from defensively equipped merchant ships (DEMS), were slow to dive if found by aircraft, offered a large sonar echo surface, and were less able to defensively maneuver during depth charge attacks. ^[1]

History

The cruiser submarine concept originated during the unrestricted submarine warfare campaign of 1917. Three German Type U 139 submarines and seven former merchant submarines, each armed with two 15-centimetre (5.9 in) guns, patrolled areas distant from their North Sea bases to sink Allied merchant shipping as part of an effort to end World War I by starving the United Kingdom of Great Britain and Ireland. These distant patrols enjoyed unique immunity to the defensive convoy measures which limited successful submarine attacks in the vicinity of the British Isles. ^[2]

The First World War combat experience of these submarines encouraged all major navies to build submarine cruiser prototypes between the world wars, but their cost discouraged most from further production. Developments were further limited by the London Naval Treaty of 1930, under which each signatory was permitted to possess no more than three large submarines, each above 2,000 tons (2,032 metric tons) but not exceeding 2,800 tons (2,845 metric tons) standard displacement, with guns not exceeding 6.1 in (150 mm) in caliber.

Japanese focus on the distances of their Pacific trade routes encouraged development of the widest variety of submarine cruisers, notably the types Junsen (巡潜, "Cruiser Submarine") including the types J, A, B, and C. Germany decided against building projected 3,140-ton type XI U-boats with an aircraft hangar and four 5-inch (13 cm) guns. ^[3] Long-range submarines with less impressive deck guns, including Type IXD2 U-boats and United States Navy fleet submarines, evolved through the Second World War; and may be identified as cruiser submarines in comparison to submarines designed for shorter patrols over lesser distances. ^[1]

Examples

Name	Nation	Surface displacement	Submerged displacement	Speed (Surfaced)	Guns	Torpedo tubes	Crew	Year	Reference
Ettore Fieramosca	Kingdom of Italy	1,530 tons	2,094 tons	15 knots (28 km/h; 17 mph)	1 ×  12cm (4.7 in) 45 caliber	14	78	1929
Surcouf	France	3,250 tons	4,304 tons	18 knots (33 km/h; 21 mph)	2 ×  203mm (8in) 50 caliber	10 [4]	118	1934	[5]
Narwhal-class	United States	2,730 tons	4,050 tons	17 knots (31 km/h; 20 mph)	2 ×  6"/53 caliber	6	90	1928	[6]
Type U-139	Germany	1,930 tons	2,483 tons	15 knots (28 km/h; 17 mph)	2 × 15 cm (5.9 in)	6	62	1916	[7]
Type U-151	Germany	1,512 tons	1,875 tons	12 knots (22 km/h; 14 mph)	2 × 15 cm (5.9 in)	6	56	1917	[7]
Type J1	Japan	2,135 tons	2,791 tons	18 knots (33 km/h; 21 mph)	2 ×  14 cm (5.5 in)/40 caliber	6	80	1926	[8]
Type B1	Japan	2,584 tons	3,654 tons	23 knots (43 km/h; 26 mph)	1 ×  14 cm (5.5 in)/40 caliber	6	100	1940	[9]
Type A3	Japan	3,603 tons	4,762 tons	16 knots (30 km/h; 18 mph)	1 ×  14 cm (5.5 in)/40 caliber	6	100	1944	[10]
HMS X1	United Kingdom	2,780 tons	3,600 tons	19 knots (35 km/h; 22 mph)	4 × 5.2 in (13 cm)	6	110	1923	[11]
Type Kaidai	Japan	1,833 tons	2,602 tons	23 knots (43 km/h; 26 mph)	1 × 12 cm (4.7 in)	6	80	1930	[12]
K class	Soviet Union	1,490 tons	2,104 tons	22.5 knots (41.7 km/h; 25.9 mph)	2 × 10 cm (3.9 in)	10	67	1939	[13]
Type IXD2	Germany	1,616 tons	1,804 tons	19 knots (35 km/h; 22 mph)	1 ×  10.5 cm (4.1 in)	6	57	1938	[13]
Cagni class	Italy	1,461 tons	2,136 tons	18 knots (33 km/h; 21 mph)	2 × 10 cm (3.9 in)	14	85	1940	[14]

Notes

1. Blair, p.501
2. Tarrant, pp.44-60
3. Lenton, pp.198&199
4. Avalanch Press page on Sucouf says 8 external tubes (2x4), apparently one each 55cm & 40cm (1x4 each), but not how many in the hull.
5. le Masson, p.157
6. Silverstone, p.186
7. Gray, p.227
8. Watts, p.167
9. Watts, p.185
10. Watts, p.200
11. Lenton & Colledge, p.136
12. Watts, p.188
13. Taylor, p.104
14. Kafka & Pepperburg, p.790

Sources

• Blair, Clay (1996). Hitler's U-Boat War. Vol. The Hunters 1939-1942. New York: Random House. ISBN   0-394-58839-8.
• Gray, Edwyn A. (1972). The Killing Time. New York: Charles Scribner's Sons.
• Kafka, Roger; Pepperburg, Roy L. (1946). Warships of the World. New York: Cornell Maritime Press.
• le Masson, Henri (1969). Navies of the Second World War. Vol. The French Navy 1. Garden City, New York: Doubleday & Company.
• Lenton, H.T. (1976). German Warships of the Second World War. New York: Arco Publishing Company. ISBN   0-668-04037-8.
• Lenton, H.T.; Colledge, J.J. (1964). British and Dominion Warships of World War II. Garden City, New York: Doubleday & Company.
• Potter, E.B.; Nimitz, Chester W. (1960). Sea Power. Englewood Cliffs, New Jersey: Prentice-Hall.
• Silverstone, Paul H. (1968). U.S. Warships of World War II. Garden City, New York: Doubleday & Company.
• Tarrant, V.E. (1989). The U-Boat Offensive 1914-1945. London: Cassell & Company. ISBN   1-85409-520-X.
• Taylor, J.C. (1966). German Warships of World War II. Garden City, New York: Doubleday & Company.
• Watts, Anthony J. (1966). Japanese Warships of World War II. Garden City, New York: Doubleday & Company.