Los Angeles-class submarine

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USS Asheville (SSN-758)2.jpg
The USS Asheville (SSN-758) arrives at Naval Base Point Loma,California in November 2005.
Class overview
Builders:Newport News Shipbuilding
General Dynamics Electric Boat
Operators: United States Navy
Preceded by:Sturgeon-class attack submarine
Succeeded by:Seawolf-class attack submarine
Built:1972–1996
In commission:1976–present
Completed:62
Active:40[1]
Laid up:1[2]
Retired:21
General characteristics
Displacement:
Surfaced: 6,082 tonnes (5,986 long tons)
Submerged: 6,927 tonnes (6,818 long tons)
Length:362 ft (110 m)
Beam:33 ft (10 m)
Draft:31 ft (9.4 m)
Propulsion:1 GE PWR S6G nuclear reactor, 2 turbines 35,000 hp (26 MW), 1 auxiliary motor 325 hp (242 kW), 1 shaft
Speed:
Surfaced:20 knots (23 mph; 37 km/h)
Submerged: +20 knots (23 mph; 37 km/h) (official),[3] 33+ knots (reported)[4][5]
Range:Refueling required after 30 years[6]
Endurance:90 days
Test depth:950 ft (290 m)
Complement:129
Sensors and
processing systems:		BQQ-5 Suite which includes Active and Passive systems SONAR, BQS-15 detecting and ranging SONAR, WLR-8V(2) ESM receiver, WLR-9 acoustic receiver for detection of active search SONAR and acoustic homing torpedoes, BRD-7 radio direction finder,[7] BPS-15RADAR
Electronic warfare
& decoys:		WLR-10 countermeasures set[7]
Armament:4× 21 in (533 mm) torpedo tubes, 37xMk 48 torpedo, Tomahawk land attack missile, Harpoon anti–ship missile, Mk 67 mobile, or Mk 60 Captor mines (most boats in service as of 2011 have a 12-tube VLS)
The Los Angeles-class, sometimes called the LA-class or the 688-class, is a class of nuclear-powered fast attack submarines that forms the backbone of the U.S. Navy's submarine force, with 62 submarines of this class being completed. As of late 2013, 41 of the class are still in commission and 21 retired from service. Of the 21 retired boats, 14 of them were laid up half way (approximately 17-18 years) through their projected lifespans due to their midlife reactor refuelings being cancelled, and one boat, USS Miami (SSN-755), due to extensive fire damage caused by arson when she was a few months into a maintenance period. A further four boats were proposed by the Navy, but later cancelled.
The Los Angeles class contains more nuclear submarines than any other class in the world. The class was preceded by the Sturgeon class and followed by the Seawolf. Except for USS Hyman G. Rickover (SSN-709), all submarines of this class are named after American cities and a few towns(e.g. Key West, Florida, and Greeneville, Tennessee). This system of naming broke a long-standing tradition in the U.S. Navy of naming attack submarines for creatures of the ocean (e.g. USS Nautilus (SSN-571)).
The final 23 boats of the Los Angeles class were designed and built to be quieter than their predecessors and also to carry more-advanced sensor and weapons systems. These advanced boats were also designed for operating beneath the polar ice cap. Their diving planes were placed at their bows rather than on their sails, and they have stronger sails for penetrating thick ice.

Characteristics[edit]

The aft end of the control room for the USS Jefferson City (SSN-759) in June 2009

Capabilities[edit]

According to the U.S. Department of Defense, the top speed of the submarines of the Los Angeles class is over 25 knots (29 mph or 46 kph), although the actual maximum is classified. Some published estimates have placed their top speed at 30 to 33 knots.[4][8] In his book Submarine: A Guided Tour Inside a Nuclear Warship, Tom Clancy estimated the top speed of Los Angeles-class submarines at about 37 knots.
The U.S. Navy gives the maximum operating depth of the Los Angeles class as 650 ft (200 m),[9] while Patrick Tyler, in his book Running Critical, suggests a maximum operating depth of 950 ft (290 m).[10] Although Tyler cites the 688-class design committee for this figure,[11] the government has not commented on it. The maximum diving depth is 1,475 ft (450 m) according to Jane's Fighting Ships, 2004–2005 Edition, edited by Commodore Stephen Saunders of the Royal Navy.[12]

Weapons and fire control systems[edit]

A portside bow view of the fore section of the USS Santa Fe(SSN-763) tied up at the pier in February 1994: The doors of the Mark 36 vertical launch system for the Tomahawk missiles are in the "open" position.
Los Angeles class submarines carry about 25 torpedo tube-launched weapons and all boats of the class are capable of launchingTomahawk cruise missiles horizontally (from the torpedo tubes). The last 31 boats of this class also have 12 dedicated vertical launching system (VLS) tubes for launching Tomahawks.

Engineering and auxiliary systems[edit]

Two watertight compartments are used in the Los Angeles-class submarines. The forward compartment contains crew living spaces, weapons-handling spaces, and control spaces not critical to recovering propulsion. The aft compartment contains the bulk of the submarine's engineering systems, power generation turbines, and water-making equipment.[13] Some submarines in the class are capable of delivering SEALs through either the dry deck shelter system or the advanced SEAL delivery system (program canceled in 2006 and rendered unusable in 2009).[14] A variety of atmospheric control devices are used to remain submerged for long periods of time without ventilating, including an electrolytic oxygen generator nicknamed "the bomb". It's called "the bomb" because it electrically removes the bonds of hydrogen and oxygen which makeup water. This produces Oxygen for the crew and highly explosive Hydrogen. The hydrogen is pumped overboard but there is always a risk of fire or explosion from this process.[6][15]
The USS Greeneville with an attached ASDS
While on the surface or at snorkel depth, the submarine may use the submarine's auxiliary or emergency diesel generator for power or ventilation[16][17] (e.g., following a fire).[18] The diesel engine in a 688 class can be quickly started by compressed air during emergencies or to evacuate noxious (nonvolatile) gases from the boat, although 'ventilation' requires raising of a snorkel mast. During nonemergency situations, design constraints require operators to allow the engine to reach normal operating temperatures before it is capable of producing full power, a process that may take from 20 to 30 minutes. However, the diesel generator can be immediately loaded to 100% power output, despite design criteria cautions, at the discretion of the submarine commander via the recommendation of the submarine's engineer, if necessity dictates such actions to a) restore electrical power to the submarine, b) prevent a reactor incident from occurring or escalating, or c) to protect the lives of the crew or others as determined necessary by the commanding officer.[19]
Normally, steam power is generated by the submarine's nuclear reactor delivering pressurized hot water to the steam generator, which generates steam to drive the steam-driven turbines and generators. While the emergency diesel generator is starting up, power can be provided from the submarine's battery through the ship service motor generators.[20] Likewise, propulsion is normally delivered through the submarine's steam-driven main turbines that drive the submarine's propeller through a reduction gear system. The submarine has no main drive shaft, unlike conventional diesel electric submarines.[21]
The USS Key West submerged at periscope depth off the coast of Honolulu, Hawaii in July 2004

In popular culture[edit]

See also[edit]

Portal iconUnited States Navy portal

Notes[edit]

  1. Jump up^ "Ship Battle Forces". Nvr.navy.mil. Retrieved 27 March 2012.
  2. Jump up^ "Navy abandons plan to fix nuclear sub". www.kjonline.com. Retrieved 2013-08-07.
  3. Jump up^ "U.S. Navy Fact Sheet - Attack Submarines - SSN". United States Navy. Retrieved 20 April 2008. "General Characteristics, Los Angeles class ... Speed: 20+ knots (23+ miles per hour, 36.8 +km/h)"
  4. ^ Jump up to:a b Polmar, Norman; Moore, Kenneth J. (2003). Cold War Submarines:The Design and Construction of U.S. and Soviet Submarines. Brassey's. p. 271. ISBN 1-57488-594-4
  5. Jump up^ "Officials: U.S. submarine hit undersea mountain". CNN. 11 January 2005. Retrieved 20 April 2008. "The submarine was traveling in excess of 33 knots - about 35 mph - when its nose hit the undersea formation head-on, officials said."
  6. ^ Jump up to:a b SSN-688 Los Angeles class from Federation of American Scientists retrieved 29 February 2008 :The 18 SSN-688 class submarines that will be refueled in their midlives could make good candidates for a service life extension because they could operate for nearly 30 years after the refueling. After these submarines serve for 30 years, they could undergo a two-year overhaul and serve for one more 10-year operating cycle, for a total service life of 42 years.
  7. ^ Jump up to:a b Polmar, Norman "The U. S. Navy Electronic Warfare (Part 1)" United States Naval Institute Proceedings October 1979 p.137
  8. Jump up^ Tyler, Patrick (1986). Running Critical. New York: Harper and Row. pp. 24, 56, 66–67. ISBN 978-0-06-091441-7.
  9. Jump up^ Waddle, Scott (2003). The Right Thing. Integrity Publishers. pp. xi (map/diagram). ISBN 1-59145-036-5. "This reference is for operating depth only"
  10. Jump up^ Tyler, (1986). pp. 66-67, 156
  11. Jump up^ "Notes in pp. 64-67: Deliberations of ad-hoc committee on SSN 688 design taken from confidential sources and from interviews with Admiral [Ret] Rickover...." From Tyler, p. 365
  12. Jump up^ Saunders, (2004). pp. 838
  13. Jump up^ SSN-688 Los Angeles Class Design. Los Angeles Class at Globalsecurity.org. Accessed on 7 January 2009
  14. Jump up^ Polmar & Moore, (2003). pp. 263
  15. Jump up^ Treadwell Supplies Oxygen Generator Components for Nuclear Subs Defense Industry Daily 28-January-2008
  16. Jump up^ Fairbanks Morse Engines Marine Installations Accessed on 29 April 2008
  17. Jump up^ Auxiliary Division on USS Cheyenne USS CHEYENNE SSN-773 Department & Divisions from Federation of American Scientists. Accessed on 29 April 2008
  18. Jump up^ Firefighting and Damage Control Update 181044Z JUN 98 (SUBS) Message COMSUBLANT (1998) Accessed on 29 April 2008
  19. Jump up^ DiMercurio, Michael; Benson, Michael (2003). The complete idiot's guide to submarines. New York, NY: Alpha Books. pp. 49–52. ISBN 978-0-02-864471-4
  20. Jump up^ Elger, Wallace (2005). "Development of Metal Fiber Electrical Brushes for 500kW SSMG Sets". Naval Engineers Journal 117(4): 37–38. doi:10.1111/j.1559-3584.2005.tb00382.x.
  21. Jump up^ Nuclear Propulsion Pressurized water Naval nuclear propulsion system at Federation of American ScientistsAccessed on 30 April 2008
  22. Jump up^ Clancy, Tom (1984). The Hunt for Red October. Naval Institute Press. pp. 71, 77, 81. ISBN 0-87021-285-0.
  23. Jump up^ Foster, Alan Dean (2009). Terminator Salvation: The Official Movie Novelization. Titan Books. ISBN 1-84856-085-0.
  24. Jump up^ Bennett, Tara (2009). Terminator Salvation: The Official Companion. Titan Books.
  25. Jump up^ "Stargate: Continuum to Film Scenes in the Arctic". comingsoon.net. March 14, 2007. Retrieved July 19, 2012.

References[edit]

External links[edit]

Wikimedia Commons has media related to Los Angeles class submarines.