An RGM-84 Harpoon missile is launched from an Mk-16 launcher aboard the Knox class frigate USS Badger (FF-1071).

Martel guided anti-ship missile.

The MBDA Exocet Anti-ship missile.

Anti-ship missiles are guided missiles designed for use against ships. Most anti-ship missiles are of the sea-skimming type and use a combination of inertial guidance and radar homing. These missiles can be launched from a variety of platforms including ships, aircraft (including helicopters), land vehicles and submarines.

The typical acronym for the phrase is ASM, but AShM can also be used to avoid confusion with air-to-surface missiles and anti-submarine missiles.

[edit] History

Anti-ship missiles were among the first instances of short range guided missiles during the Second World War. The German Luftwaffe used Fritz X and others to some effect against Allied shipping and sank or damaged a number of large warships successfully before the Allies devised countermeasures (principally radio jamming). The Allies also developed similar weapons, such as Tiny Tim and the SWOD-9 Bat.

During the cold war, the USSR turned to a sea-denial strategy concentrating on submarines, mines, and anti-ship missiles. One of the first products of the decision was the SS-N-2 Styx missile. Further products were to follow and soon found the in the aircraft launched KS-1 Komet carried by Tu-95 Bear and Tu-22 Badger bombers.

In 1967 the Israeli Navy destroyer Eilat was sunk by a Styx missile launched by Egyptian missile boats off the Sinai Peninsula.

1973's Battle of Latakia was the site of the world's first combat between anti-ship missile-equipped missile boats. In it, the Israeli navy destroyed the Syrian ships without suffering any damage, using electronic countermeasures.

Anti-ship missiles were used in the 1982 Falklands War. HMS Sheffield, a 4,820 ton Type 42 Destroyer was struck by a single air-launched Exocet missile and later sank as a result of damage sustained. The container ship Atlantic Conveyor was also sunk by an Exocet, while HMS Glamorgan was damaged. Glamorgan was struck by an MM38 missile launched from an improvised trailer-based launcher taken from the destroyer ARA Comodoro Seguí by Argentine Navy technicians.^[1], but was able to take avoiding manoeuvres that lessened the damage inflicted.

In 1987, a US Navy guided-missile frigate, the USS Stark, was hit by an Exocet ASM fired by an Iraqi Mirage F-1. The Stark was damaged but was able to make it to a friendly port for repair. The next year, ASMs were fired by both US and Iranian forces in Operation Praying Mantis in the Persian Gulf. During this naval battle, several Iranian warships were hit by US ASMs (and by Standard SAMs doing double-duty in this role). Also, in October 1987, Sungari, an American-owned tanker under the Liberian flag and a Kuwaiti tanker under the US flag, the Sea Isle City, were hit by Iranian HY-2 missiles.

During Operation Praying Mantis, the US Navy hit the Iranian light frigate IS Sahand with 3 Harpoon missiles, 4 AGM-123 Skipper rocket-propelled bombs, a Walleye laser-guided bomb, and several 1,000 lb bombs. Despite the large number of munitions and successful hits, the 1,540 ton IS Sahand did not sink until fire reached its munitions magazine, causing it to explode. [1] However, in the same engagement, US warships fired 3 RIM-66 Standard missiles at an Iranian corvette - the corvette sunk low enough in the water that a Harpoon missile arriving several minutes later had nothing to lock on to.

In 2006, Hezbollah forces fired an ASM at the Israeli corvette INS Hanit, inflicting damage but the ship made it back to Israel. A second missile in this salvo sunk an Egyptian merchant ship, as well.

[edit] Comparison

[edit] Threat posed

Anti-ship missiles are the bane of the modern naval surface combatant. Unlike the ground-combatant, who has the advantage of concealment, terrain, and, fundamentally, ground beneath his feet, the naval surface combatant is alone, aboard a warm boat, easily distinguishable from the cold water that surrounds her, said boat being packed to the gills with men, weaponry, and explosives, sailing on a flat, relatively featureless expanse of ocean, which offers concealment and shelter to none, and is (eventually) naturally deadly to human life. As this is the case, threats that would merely slow down the ground combatant—such as guided missiles—are a much greater threat to the naval combatant. Possessing a speed and an agility that naval platforms cannot forseeably match, as well as computerized "smart" guidance systems and a heavy payload of high-explosive, the modern anti-ship missile, once it has acquired its target, is an enemy that the target ship cannot usually run from, hide from, physically avoid, or absorb.

Therefore, to counter the threat posed, the modern surface combatant has to either avoid being acquired by a platform possessing anti-ship missiles in the first place, has to destroy the anti-ship missile carrying platform prior to it launching its anti-ship missiles, or has to have active defense systems capable of deceiving or destroying the anti-ship missile prior to the anti-ship missile hitting its target. Modern navies have spent thousands, if not millions of man-years considering and responding to the threat of anti-ship missiles since World War II, and the multiple, layered, computerized, active defense systems that they field aboard their surface combatants are extremely effective against almost all anti-ship missiles, with certain exceptions.

For example, the United States Navy has developed the computerized, automatic AEGIS anti-missile/anti-air/anti-satellite naval defense system, which is claimed to be able to track, engage, and destroy massive, though finite, quantities of incoming missiles (all at the same time) using agile long-range surface to air missiles. Any missiles that leak through the AEGIS system can then be deceived using electronic countermeasures or decoys, or defeated by a Close-in weapon system, such as the Phalanx and Goalkeeper CIWSes, or short-range anti-aircraft missiles, like the Sea Sparrow or the Rolling Airframe Missile. Russia (and the former USSR), various European nations, and the People's Republic of China have developed and deployed similar systems.

However, even as effective as these naval air defense systems are, they only retain their effectiveness as long as they retain their ammunition. And, even as expensive as the most-effective, modern anti-ship missiles are, they still remain extremely cost-effective, and do not lose this cost-effectiveness when launched in their most dangerous threat modality - namely, in massive, defense-saturation-level quantities - as the replacement cost of a single Nimitz-class supercarrier, not to mention the irreplaceable crew on board, is far in excess of even 1,000 of the most modern anti-ship missiles available, a quantity that, if launched en masse, would surely devastate even the most well-defended carrier that any sea-faring power could conceivably deploy.

As such, navies place a high premium on defending against anti-ship missiles, as even a handful getting through ship-based defenses could easily decimate an entire fleet.

[edit] Current Threats and Vulnerabilities

To counter these defense systems, countries like Russia are developing or deploying very low flying missiles (~5 m ASL) that slowly cruise at a very low level to within a short range of their target and then, at the point when radar detection becomes inevitable, initiate a supersonic, high-agility sprint (potentially with anti-aircraft missile detection and evasion) to close the terminal distance. Missiles, such as the SS-N-27 Sizzler, that incorporate this sort of threat modality are regarded by U.S. naval analysts as potentially being able to penetrate current US Navy defensive platforms.^[2]

[edit] Countermeasures

Countermeasures against anti-ship missiles include:

• Anti-missile missiles (such as the Sea Sparrow, SA-N-6 Grumble, SA-N-9 Gauntlet, RAM, Standard or Sea Wolf missile)
• Close-in weapon systems (CIWS), including the Phalanx CIWS or the Goalkeeper CIWS. These are automated gun systems mounted on the deck of a ship which use radar to track the approaching missile and attempt to shoot it down during its final approach on the target.
• Anti-aircraft guns such as the Mk. 45 or the AK-130
• Electronic warfare equipment (such as SLQ-32)
• Decoy systems (such as "chaff" and "flares" or more active decoys such as the Nulka)

Modern stealth ships – or ships that at least employ some stealth technology – to reduce the risk of detection and to make them harder target by the missile itself. These passive countermeasures include:

• reduction of their radar cross section (RCS) and hence radar signature.
• limit a ship's infrared signature and acoustic signature.

Examples include the Norwegian Skjold class patrol boats, Swedish Visby class corvettes, the German Sachsen class frigates, the US Arleigh Burke class destroyers, the Chinese Type 054 frigates, Chinese Type 052C destroyers, Indian INS Shivalik Class, and the French La Fayette class frigates.

[edit] Notes

[edit] See also

• List of anti-ship missiles

[edit] External links

• Warship Vulnerability (tabulated shipping losses)
• List of SSSR/Russian anti-ship missiles