View source for Squid (weapon)

{{short description|Depth charge mortar}}
{{Use dmy dates|date=June 2017}}
{{Infobox weapon
|name= Squid
| image= Squid Mortar.jpg
| image_size = 300
|caption= Squid anti-submarine mortar on display at the [[Devonport Naval Base]]
|origin= United Kingdom
|type= Anti-submarine Mortar
<!-- Type selection -->
|is_ranged=yes
|is_bladed=
|is_explosive=yes
|is_artillery=yes
|is_vehicle=
|is_missile=
|is_UK=yes
<!-- Service history -->
|service= 1943–1977
|used_by=[[Royal Navy]], [[Swedish Navy]], [[Royal Canadian Navy]]
|wars=
<!-- Production history -->
|designer= [[Directorate of Miscellaneous Weapons Development]]
|design_date=1942
|manufacturer=
|unit_cost=
|production_date=
|number=
|variants=
<!-- General specifications -->
|spec_label=
|weight= 10 tons
|length=
|part_length=
|width=
|height=
|diameter=
|crew=
<!-- Ranged weapon specifications -->
|cartridge= 440 lb (200 kg)
|caliber=12 in (305 mm)
|barrels=Three
|action=
|rate=
|velocity=
|range= 275 yards (250 m)
|max_range=
|feed=
|sights=
<!-- Artillery specifications -->
|breech=
|recoil=
|carriage=
|elevation=
|traverse=
<!-- Explosive specifications -->
|filling=[[Minol (explosive)|Minol II]]
|filling_weight=207 lb (94 kg)
|detonation=Time fuse
|yield=
}}
'''Squid''' was a British [[World War II]] [[ship]]-mounted [[anti-submarine warfare|anti-submarine]] [[weapon]]. It consisted of a three-barrelled [[mortar (weapon)|mortar]] which launched [[depth charge]]s. It replaced the [[Hedgehog (weapon)|Hedgehog]] system, and was in turn replaced by the [[Limbo (weapon)|Limbo]] system.

== Development ==
Ordered directly from the drawing board in 1942, under the auspices of the [[Directorate of Miscellaneous Weapons Development]], this weapon was rushed into service in May 1943 on board [[HMS Ambuscade (D38)|HMS ''Ambuscade'']]. The first production unit was installed on [[HMS Hadleigh Castle (K355)|HMS ''Hadleigh Castle'']]; it went on to be installed on 70 frigates and corvettes during the [[Second World War]]. The first successful use was by [[HMS Loch Killin|HMS ''Loch Killin'']] on 31 July 1944, when she sank {{GS|U-333||2}}. 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 British [[depth charge]] attacks in WWII there were 85.5 kills,{{efn|A "half" value indicates a kill shared with a non-British entity.}} a ratio of 60.5 to 1. The [[Hedgehog (weapon)|Hedgehog]] made 268 attacks for 47 kills, a ratio of 5.7 to 1.<ref name="AB XDW">{{cite web|url=http://www.navweaps.com/Weapons/WAMBR_ASW.htm|title=Britain ASW Weapons|publisher=www.navweaps.com|access-date=28 May 2015}}</ref> By 1959, 195 Squid installations had been produced.

This weapon was a three-barrel {{convert|12|in|mm|0|adj=on}} 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&nbsp;degrees for loading.  The projectiles weighed {{convert|390|lb|kg|0}} with a {{convert|207|lb|kg|0|adj=on}} [[Minol (explosive)|minol II]] charge.{{efn|Due to shortages of [[trinitrotoluene|TNT]] and [[RDX]] (cyclonite) in World War II, the British used a 50/50 mixture of [[ammonium nitrate]] and TNT ([[amatol]]) in [[naval mine]]s and depth charges. This low-grade explosive was later improved by the addition of about 20% [[aluminium]] powder, producing ''[[Minol (explosive)|minol]]''.}}<ref>{{cite book |last1=Wagner |first1=Margaret E. |last2=Kennedy |first2=David M. |last3=Osborne |first3=Linda Barrett |last4=Reyburn |first4=Susan |title=The Library of Congress World War II companion |date=2007 |publisher=Simon & Schuster |location=New York |isbn=978-0-7432-5219-5 |page=379}}</ref> 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.<ref name="hmcshaida">{{cite web|url=http://hmcshaida.ca/squid.html|title=Squid Mortar|publisher=Friends of HMCS Haida|access-date=21 March 2012|url-status=dead|archive-url=https://web.archive.org/web/20120217023650/http://www.hmcshaida.ca/squid.html|archive-date=17 February 2012|df=dmy-all}}</ref> Sink rate was 43.5&nbsp;ft/s (13.3&nbsp;m/s) and a clockwork time [[Fuse (explosives)|fuze]] was 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.<ref name="hmcshaida"/> The maximum depth was {{convert|900|ft|m}}.
The weapons were automatically fired from the [[sonar]] range recorder at the proper moment. The pattern formed a triangle about {{convert|40|yd|m}} on a side at a distance of {{convert|275|yd|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 {{convert|25|ft|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.<ref>{{Cite book|last=Zimmerman|first=David|title=Great Naval Battle of Ottawa|location=Toronto|publisher=University of Toronto Press|isbn=0802026877|year=1989|p=127}}</ref>

== Usage ==
Despite its proven effectiveness, some officers, notably [[Royal Canadian Navy]] [[Captain (naval)|Captain]] Kenneth Adams opposed fitting Squid to escorts because it meant sacrificing guns which would make ships unsuitable for fleet actions.{{sfnp|Zimmerman|1989|pages=128–129}}

In April 1977, the [[Type 61 frigate]] ''[[HMS Salisbury (F32)|Salisbury]]'' became the last ship to fire Squid in Royal Navy service. Examples of the mortars are on display at the [[Explosion! Museum of Naval Firepower]] in Gosport, Hampshire and another at Devonport Naval Base. The system is fitted to {{HMS|Cavalier|D73}}, which is part of the historic ships collection in the Historic Dockyard in Chatham, Kent.  It can also be seen on {{HMCS|Haida|}}, which is on display in [[Hamilton, Ontario]] and at the naval museum in [[Malacca]], [[Malaysia]].

The [[Swedish Navy]] continued to use the Squid system until 1982 when the [[Östergötland-class destroyer|''Östergötland''-class destroyers]] were decommissioned.

==Gallery==
{{multiple image|footer=|align= center|image1=Sailors loading Squid anti-submarine mortar in 1952.jpg|width1=214|caption1=Loading a Squid in 1952

|image2=Squid bomb markings diagram.jpg|width2=240|caption2=Squid bomb markings diagram

|image3=HMCS Haida Hamilton Ontario june07 10.jpg|width3=254|caption3={{HMCS|Haida}}

|image4=HMS Cavalier at Chatham 10.jpg|width4=234|caption4={{HMS|Cavalier}}}}

==Notes==
{{notelist}}
{{reflist|group=Note|colwidth=60em}}

==References==
{{Commons category}}
=== Citations===
{{reflist}}

=== Bibliography===
{{refbegin|colwidth=60em}}
* ''Jane's Naval Weapon Systems'' Issue 33, E R Hooton, {{ISBN|0-7106-0893-4}}
* ''Naval Armament'', Doug Richardson, 1981, Jane's Publishing, {{ISBN|0-531-03738-X}}
{{Refend}}

{{WWIIBritishCommNavalWeapons}}

{{DEFAULTSORT:Squid (Weapon)}}
[[Category:Explosive weapons]]
[[Category:Anti-submarine mortars]]
[[Category:Naval weapons of the United Kingdom]]
[[Category:World War II naval weapons of the United Kingdom]]
[[Category:World War II mortars]]
[[Category:305 mm artillery]]
[[Category:Weapons and ammunition introduced in 1943]]