Squid (weapon)

Squidwas a BritishWorld War IIship-mountedanti-submarineweapon.It consisted of a three-barrelledmortarwhich launcheddepth charges.It replaced theHedgehogsystem, and was in turn replaced by theLimbosystem.

Squid
Squid anti-submarine mortar on display at theDevonport Naval Base
Type	Anti-submarine Mortar
Place of origin	United Kingdom
Service history
In service	1943–1977
Used by	Royal Navy,Swedish Navy,Royal Canadian Navy
Production history
Designer	Directorate of Miscellaneous Weapons Development
Designed	1942
Specifications
Mass	10 tons
Shell	440 lb (200 kg)
Calibre	12 in (305 mm)
Barrels	Three
Effective firing range	275 yards (250 m)
Filling	Minol
Filling weight	207 lb (94 kg)
Detonation mechanism	Time fuse

Development

Ordered directly from the drawing board in 1942, under the auspices of theDirectorate of Miscellaneous Weapons Development,this weapon was rushed into service in May 1943 on boardHMSAmbuscade.The first production unit was installed onHMSHadleigh Castle;it went on to be installed on 70 frigates and corvettes during theSecond World War.The first successful use was byHMSLoch Killinon 31 July 1944, when she sankU-333.The system was credited with sinking 17 submarines in 50 attacks over the course of the war - a success ratio of 2.9 to 1. In contrast, out of 5,174 Britishdepth chargeattacks in WWII there were 85.5 kills, a ratio of 60.5 to 1. TheHedgehogmade 268 attacks for 47 kills, a ratio of 5.7 to 1.By 1959, 195 Squid installations had been produced.

This weapon was a three-barrel 12-inch (305 mm) mortar with the mortars mounted in series but off-bore from each other in order to scatter the projectiles. The barrels were mounted in a frame that could be rotated through 90 degrees for loading. The projectiles weighed 390 pounds (177 kg) with a 207-pound (94 kg)minolcharge.On some vessels, the Squid installations were at the stern – the bombs were fired over the length of the ship and dropped into the sea slightly ahead of it.Sink rate was 43.5 ft/s (13.3 m/s) and a clockwork timefuzewas used to determine the detonation depth. All three projectiles had to be set to the same depth; this could be continuously updated right up to the moment of launch to take into account the movements of the target.The maximum depth was 900 feet (270 m).

The weapons were automatically fired from thesonarrange recorder at the proper moment. The pattern formed a triangle about 40 yards (37 m) on a side at a distance of 275 yards (251 m) ahead of the ship. Most Squid installations utilised two sets of mortars. All six bombs were fired in salvo so they formed opposing triangular spreads. The salvos were set to explode 25 feet (7.6 m) above and below the target, the resulting pressure wave crushing the hull of the submarine. Post-war trials found Squid was nine times more effective than conventional depth charges.

Use

Despite its proven effectiveness, some officers, notablyCaptainKenneth Adams,RCN,opposed fitting Squid to escorts because it meant sacrificing guns, which would make ships unsuitable for fleet actions.

In April 1977, theType 61 frigateSalisburybecame the last ship to fire Squid in Royal Navy service. Examples of the mortars are on display at theExplosion! Museum of Naval Firepowerin Gosport, Hampshire and another at Devonport Naval Base. The system is fitted toHMSCavalier(D73),which is part of the historic ships collection in the Historic Dockyard in Chatham, Kent. It can also be seen onHMCSHaida,which is on display inHamilton, Ontarioand at the naval museum inMalacca,Malaysia.

In Swedish service the system soldiered on until 1982 when theÖstergötland-class destroyerswere decommissioned.

Gallery

Loading a Squid in 1952

Squid bomb markings diagram

HMCSHaida

HMSCavalier

References

Bibliography

• Jane's Naval Weapon SystemsIssue 33, E R Hooton,ISBN0-7106-0893-4
• Naval Armament,Doug Richardson, 1981, Jane's Publishing,ISBN0-531-03738-X