Mark 18 torpedo
Mark 18 torpedo | |
---|---|
Produced | 1943-1945[2] |
No. built | 9000[2] |
Specifications | |
Mass | 3,154 lb (1,431 kg)[1] |
Length | 245 in (6.2 m)[1] |
Diameter | 21 in (530 mm)[1] |
Effective firing range | 4,000 yd (3,700 m)[1] |
Warhead | Mod 0 Torpex, Mod 2 Torpex/HBX,[3] Mod 3, HBX[1] |
Warhead weight | Mod 0 600 lb (272 kg), Mod 2 595 lb (270 kg),[3] Mod 3 575 lb (261 kg)[1] |
Detonation mechanism | Mk 8 contact exploder, Mk 9 contact/influence exploder[1] |
Engine | Electric motor[1] |
Maximum speed | 29 kn (54 km/h)[1] |
Guidance system | Gyroscope[1] |
Launch platform | Submarines[1] |
The Mark 18 torpedo was an electric
Development
![](http://upload.wikimedia.org/wikipedia/commons/thumb/c/c4/Torpedos_axb01.jpg/220px-Torpedos_axb01.jpg)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/f/f7/Mark_18_torpedo%27s_electric_motor%2C_forward_end%2C_April_1943.jpg/220px-Mark_18_torpedo%27s_electric_motor%2C_forward_end%2C_April_1943.jpg)
The Mark 18 was built in competition with the
In 1942, several German
Westinghouse quickly decided to copy the G7e, and "went to work with a speed and fervor that was dazzling"[6] (certainly in comparison to NTS's languid pace). Design was complete by mid-April, and a contract for 2,000 Mark 18s, 2,020 warheads, 543 exercise heads (for training shots), tools, spares, and workshop gear was issued 2 May. The first test models were delivered just 15 weeks after Westinghouse started work[5] and the Mark 18 was promised to the Submarine Force by summer 1942.[7]
Problems
![](http://upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Mark_18_torpedo_battery_monoblock_container%2C_April_1943.jpg/220px-Mark_18_torpedo_battery_monoblock_container%2C_April_1943.jpg)
The batteries (provided by
Deployment
The first submarines to use Mark 18s (still not perfected) were
Characteristics
The Mark 18 did not produce a wake of bubbles or turbine exhaust pointing back to the submarine firing it - a major advantage in daytime engagements. The torpedo also lacked the depth-keeping and exploder problems that had plagued the Mark 14. The disadvantages were the low speed compared to the Mark 14's 45 kn (83 km/h; 52 mph), the need to regularly withdraw the torpedoes from their tubes for recharging, sensitivity of the batteries to water temperature,[16] and onerous maintenance procedures. The Mark 18 shared one major flaw with the Mark 14: it had no protection against circular runs, a defect which claimed Tang for certain, and possibly other U.S. submarines, as well; "Donc" Donaho's Flying Fish was nearly sunk by a trial model in October 1943.[17]
Some 30% of torpedoes fired by U.S. submarines in the Pacific War were Mark 18s.[18]
The design was dropped from service in 1950 in favor of faster and more reliable later types.[19]
The Mark 18 was 20 feet (6.1 m) long, weighed 3,154 pounds (1,431 kg), had a warhead of 575 pounds (261 kg) of Torpex with a contact exploder, and had a speed of 29 knots (54 km/h; 33 mph) and a maximum range of 4,000 yards (3,700 m). By July 1944, an improved version had appeared.[4][20]
See also
- American 21 inch torpedo
References
- ^ a b Jolie, E.W. (15 September 1978). "A Brief History of U.S. Navy Torpedo Development". Retrieved 5 June 2013.
- ^ ISBN 978-1-59114-688-9
- ^ a b U.S. Navy Torpedo Mark 18 (Electric), Description, Adjustment, Care, and Operation. United States Navy. April 1943.
- ^ a b c d e f g h i Blair, Clay Jr. (1976), Silent Victory, New York: Bantam, p. 280
- ^ Blair 1976, p. 281
- ^ a b Blair 1976, p. 402
- ^ a b Blair 1976, p. 403
- ^ Blair 1976, pp. 402, 469
- ^ Blair 1976, p. 479
- ^ Blair 1976, p. 404 & passim
- ^ Blair 1976, p. 510
- ^ Blair 1976, p. 939
- ^ Blair 1976, p. 511. The Mark 14, at least, would leave the tube correctly.
- ^ Blair 1976, p. 511
- ^ Blair 1976, p. 509
- ^ Blair 1976, pp. 513, 939
- ^ Blair 1976, 694fn and p. 818
- ^ USA Torpedoes of World War II
- ^ Blair 1976, 694fn
Bibliography
- Grulich, Fred (2003). "Loss of the Battleship Royal Oak". Warship International. XL (2): 133. ISSN 0043-0374. discusses how the Mk 18 was based on the G7e
External links