RUR-5 ASROC

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"ASROC" redirects to this page. For the vertical-launch variant, see RUM-139 VL-ASROC.

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RUR-5 ASROC
ASROC Launcher
Type	Standoff Anti-Submarine
Place of origin	United States
Service history
In service	1961[1]
Used by	United States Navy and others
Production history
Manufacturer	Honeywell[1]
Unit cost	Approximately $350,000 (less torpedo payload)
Specifications
Weight	1073 lb (488 kg)[1]
Length	14.75 ft (4.5 m)[1]
Diameter	16.6 in (422 mm)
Warhead	Mark 46 torpedo, 96.8 lb (44 kg)[1] of PBXN-103 high explosive; 10kt W44 Nuclear Warhead (Retired)
Detonation mechanism	Payload Specific
Engine	Solid propellant rocket motor[1]
Wingspan	26 7/8 in (683 mm)
Operational range	12 nm (22 km)[1]
Speed	Subsonic
Guidance system	Inertial guidance
Launch platform	Surface Ship

ASROC (for Anti-Submarine ROCket) is an all-weather, all sea-conditions anti-submarine missile system. Developed by the United States Navy in the 1950s, it was deployed in the 1960s, updated in the 1990s, and eventually installed on over 200 USN surface ships, specifically cruisers, destroyers, and frigates. The ASROC has been deployed on scores of warships of many other navies, including Canada, Germany, Italy, Japan, the Republic of China, Greece, Pakistan and others.^[2]

[edit] Description

After a surface ship, patrol plane or anti-submarine helicopter detects an enemy submarine by using sonar and/or other sensors, it could relay the sub's position to an ASROC-equipped ship for attack. The attacking ship would then fire an ASROC missile carrying an acoustic homing torpedo or a Nuclear Depth Bomb (NDB) onto an unguided ballistic trajectory toward the target. At a pre-determined point on the missile's trajectory, the payload separates from the missile and deploys a parachute to permit splashdown and water entry at a low speed and with minimum detectable noise. The water entry activates the torpedo, and guided by its own sonar system, it homes in on the target using either active sonar or passive sonar.

In cases where the ASROC missile carried an NDB, the unguided bomb would sink quickly to a predetermined depth where it would detonate. The nuclear-armed ASROC was never used beyond one or two tests in 1961-62. Eventually the Limited Nuclear Test Ban Treaty banning underwater nuclear tests went into effect. The nuclear weapon was never used in combat. An ASROC missile could hypothetically carry a 10 kiloton W44 nuclear warhead, although the W44-armed nuclear weapons were retired by 1989, and all types of nuclear depth bombs were removed from deployment.^[2]

Destroyer USS Agerholm fires an ASROC with a nuclear depth bomb in the "Swordfish" test in 1962

The first ASROC system using the MK-112 "Matchbox" launcher, was developed in the 1950s and installed in the 1960s. This system was phased out in the 1990s and replaced with the RUM-139 Vertical Launch ASROC, or "VLA".^[2]

ASROC 'Matchbox' mounting installed just aft of the 76 mm gun turret on the Japanese Self Defense Force Asagiri class destroyer DD 158 Umigiri, photographed 28 July 2008 departing from Portsmouth Naval Base, UK.

ASROC 'Matchbox' reload doors can clearly be seen in this photograph of the Japanese Asagiri class destroyer Asagiri, formerly DD 156, renumbered TV 3516 after reclassification as a training vessel, seen here on 28 July 2008 departing from Portsmouth Naval Base, UK.

[edit] Specific Installations

The thirty-one U.S. Navy Spruance-class destroyers were all built in the shipyard with the Mark 112 ASROC launcher and reload system. These had one standard Mark 16 octuple ASROC launcher, located immediately above a reload system holding an additional 16 assembled rounds (two complete reloads of eight missiles apiece). Thus, each Spruance-class destroyer originally carried a total of 24 ASROC.^[3]

Most other U.S. Navy and allied navy destroyers, destroyer escorts, frigates, and several different classes of cruisers only carried the one ASROC 'matchbox' launcher with eight ASROC missiles (although later in service, some of those missiles could be replaced by the Harpoon anti-ship missile). The "matchbox" Mk 112 launchers were capable of carrying a mixture of the two types. Reloads were carried in many classes, either on first level of the superstructure immediately abaft the launcher, or in a separate deckhouse just forward or abaft the Mk 112.

Ships with the Mk 26 GMLS, and late marks of the Mk 10 GMLS aboard the "Belknap"-class, could accommodate ASROC in these power-loaded launchers (the Mk 13 GMLS was not able to fire the weapon, as the launcher rail was too short).

Most Spruance-class destroyers were later modified to include the MK 41 VLS, these launchers are capable of carrying a mixture of the VL-ASROC, the Tomahawk TLAM, and other missiles. All of the Spruance destroyers carried two separate quad Harpoon launchers. Other US ships with the Mk 41 can also accommodate VL-ASROC.

[edit] See also

Wikimedia Commons has media related to: ASROC

• Ikara
• Hong Sang Eo (Red Shark) rocket-based torpedo (K-ASROC)

• Malafon
• MILAS
• RUM-139 VL-ASROC
• Sea Lance
• SUBROC

[edit] References

[edit] External links

• http://www.fas.org/man/dod-101/sys/missile/vla.htm
• http://www.gyrodynehelicopters.com/asroc.htm
• http://designation-systems.net/dusrm/r-5.html