The Loch class was a

class Class or The Class may refer to: Common uses not otherwise categorized * Class (biology), a taxonomic rank * Class (knowledge representation), a collection of individuals or objects * Class (philosophy), an analytical concept used differently ...

anti-submarine An anti-submarine weapon (ASW) is any one of a number of devices that are intended to act against a submarine and its crew, to destroy (sink) the vessel or reduce its capability as a weapon of war. In its simplest sense, an anti-submarine weapo ...

(A/S)

frigate A frigate () is a type of warship. In different eras, the roles and capabilities of ships classified as frigates have varied somewhat. The name frigate in the 17th to early 18th centuries was given to any full-rigged ship built for speed an ...

built for the

Royal Navy The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against Fr ...

and her

Allies An alliance is a relationship among people, groups, or states that have joined together for mutual benefit or to achieve some common purpose, whether or not explicit agreement has been worked out among them. Members of an alliance are called ...

during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...

. They were an innovative design based on the experience of three years of fighting in the

Battle of the Atlantic The Battle of the Atlantic, the longest continuous military campaign in World War II, ran from 1939 to the defeat of Nazi Germany in 1945, covering a major part of the naval history of World War II. At its core was the Allies of World War II, ...

and attendant technological advances. Some shipyards had trouble building these larger ships, which led to widespread use of the

Castle-class corvette The Castle-class corvette was an ocean going convoy escort developed by the United Kingdom during the Second World War. It was the follow-on to the , and designed to be built in shipyards that were producing the Flowers. The Castle-class was a ...

, introduced around the same time.

Design

The Lochs were based upon the hull of the preceding with increased sheer and

flare A flare, also sometimes called a fusée, fusee, or bengala in some Latin-speaking countries, is a type of pyrotechnic that produces a bright light or intense heat without an explosion. Flares are used for distress signaling, illumination, ...

to improve seakeeping and modified to suit it to mass pre-fabrication, with sections

rivet A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite to the head is called the ''tail''. On installation, the rivet is placed in a punched ...

ed or

welded Welding is a fabrication process that joins materials, usually metals or thermoplastics, by using high heat to melt the parts together and allowing them to cool, causing fusion. Welding is distinct from lower temperature techniques such as braz ...

together at the shipyard. Accordingly, as many curves as possible were eliminated, producing a noticeable kink in the main deck where the increased sheer forwards met the level abreast the bridge. The fighting capability of the Loch class was a great jump forward, being based around the new

Squid True squid are molluscs with an elongated soft body, large eyes, eight arms, and two tentacles in the superorder Decapodiformes, though many other molluscs within the broader Neocoleoidea are also called squid despite not strictly fittin ...

ahead-throwing A/S mortar. Previously, escorts had attacked with depth charges, requiring the attacking vessel to pass over the submerged submarine and drop warheads over the stern. Consequently, the ahead-looking

ASDIC Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances ( ranging), communicate with or detect objects on ...

(sonar) set lost contact at the vital moment before the weapons were launched, allowing a skilled submarine commander to take successful evasive action. Squid, however, lobbed three , 390 pound warheads up to ahead of the launching vessel falling in a triangular pattern with sides of . As the clockwork fuses detonated the warheads at a depth determined by the ships' ASDIC set, the Squid therefore attacked in full ASDIC contact for greater accuracy and lethality. Two mortars were carried, with the bombs set to explode at different depths in order to create a convergent pressure wave to crush the hull of a submarine. The first successful "kill" was by on 31 July 1944, sinking the . Such was the utility of Squid that

depth charge A depth charge is an anti-submarine warfare (ASW) weapon. It is intended to destroy a submarine by being dropped into the water nearby and detonating, subjecting the target to a powerful and destructive hydraulic shock. Most depth charges use h ...

carriage was reduced to only 15, with a single rack and a pair of throwers being carried at the stern, resulting in a clear quarterdeck compared to the eight throwers, two racks and stowage for 100 plus charges in the Rivers. The weapons outfit was completed with a single QF Mark V gun forwards. An oversight in the River design had been to place the gun in the favourable position forward on the shelter deck, with the ahead throwing

Hedgehog A hedgehog is a spiny mammal of the subfamily Erinaceinae, in the eulipotyphlan family Erinaceidae. There are seventeen species of hedgehog in five genera found throughout parts of Europe, Asia, and Africa, and in New Zealand by introductio ...

on the main deck, exposed to the worst of the seas breaking over the

fo'c'sle The forecastle ( ; contracted as fo'c'sle or fo'c's'le) is the upper deck of a sailing ship forward of the foremast, or, historically, the forward part of a ship with the sailors' living quarters. Related to the latter meaning is the phrase " be ...

, consequently this was reversed in the Lochs; the Squids being on the shelter deck behind protective bulwarks. For anti-aircraft (A/A) defence, a quadruple mounting Mark VII QF 2-pounder was shipped aft along with up to 12 20 mm Oerlikon guns, in 2 twin powered mounts Mark V in the bridge wings and 8 single pedestal mounts Mark III. , ''Loch Craggie'', ''Loch Eck'', ''Loch Glendhu'', and the

South African Navy The South African Navy (SA Navy) is the naval warfare branch of the South African National Defence Force. The Navy is primarily engaged in maintaining a conventional military deterrent, participating in counter-piracy operations, fishery pro ...

ships HMSAS ''Good Hope'', ''Natal'' and ''Transvaal'' carried single

Bofors 40 mm L/60 gun The Bofors 40 mm Automatic Gun L/60 (often referred to simply as the "Bofors 40 mm gun", the "Bofors gun" and the like, see name) is an anti-aircraft autocannon, designed in the 1930s by the Swedish arms manufacturer AB Bofors. The g ...

mounts in lieu of the twin Oerlikons. In addition to the new weaponry, the Lochs also carried new sensors, in the form of Radar Type 277. This set utilised the

cavity magnetron The cavity magnetron is a high-power vacuum tube used in early radar systems and currently in microwave ovens and linear particle accelerators. It generates microwaves using the interaction of a stream of electrons with a magnetic field whi ...

to transmit on centimetric wavelengths for target indication purposes, excelling at picking out small targets such as a

submarine A submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has more limited underwater capability. The term is also sometimes used historically or colloquially to refer to remotely op ...

periscope A periscope is an instrument for observation over, around or through an object, obstacle or condition that prevents direct line-of-sight observation from an observer's current position. In its simplest form, it consists of an outer case with ...

or snorkel from the surface clutter. The increased weight of the stabilised antenna array and the carriage of

HF/DF High-frequency direction finding, usually known by its abbreviation HF/DF or nickname huff-duff, is a type of radio direction finder (RDF) introduced in World War II. High frequency (HF) refers to a radio band that can effectively communicate ove ...

at the masthead meant that a lattice mast was stepped in lieu of the traditional tripod or pole. Some vessels completed with Radar Type 271 or 272 and the associated "lantern"

radome A radome (a portmanteau of radar and dome) is a structural, weatherproof enclosure that protects a radar antenna. The radome is constructed of material transparent to radio waves. Radomes protect the antenna from weather and conceal antenna e ...

until Type 277 became available. ASDIC Type 144 was carried for search and attack functions with Type 147B used for depth finding. As with the previous wartime escort designs, mercantile machinery was adopted to speed construction, with a pair of 4-cylinder vertical triple-expansion reciprocating engines. ''Loch Arkaig'' and ''Loch Tralaig'' were fitted with

Parsons Parsons may refer to: Places In the United States: * Parsons, Kansas, a city * Parsons, Missouri, an unincorporated community * Parsons, Tennessee, a city * Parsons, West Virginia, a town * Camp Parsons, a Boy Scout camp in the state of Washingt ...

single reduction

steam turbines A steam turbine is a machine that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft. Its modern manifestation was invented by Charles Parsons in 1884. Fabrication of a modern steam turbin ...

to establish the feasibility of such an installation, but it was not possible to provide enough sets of turbines for all vessels. One advantage of the use of mercantile machinery was that it was instantly familiar to the mainly reservist and volunteer (

RNR The Royal Naval Reserve (RNR) is one of the two volunteer reserve forces of the Royal Navy in the United Kingdom. Together with the Royal Marines Reserve, they form the Maritime Reserve. The present RNR was formed by merging the original Ro ...

and RNVR) crews who manned these ships.

Service

Of the one hundred and ten vessels ordered, twenty-eight were built as frigates, entering service from 1944. Another two – ''Loch Assynt'' and ''Loch Torridon'' – were converted while building and completed as Coastal Forces Depot Ships, being renamed and . Due to a need in 1944 for a version fitted as anti-aircraft vessels with the British Pacific Fleet, twenty-six units were authorised for completion to a modified design labelled the and were renamed. A further fifty-four Loch-class vessels were cancelled in 1945. Of the twenty-eight Loch-class frigates completed as such, ''Loch Achanalt'', ''Loch Alvie'' and ''Loch Morlich'' were transferred to Canada in 1943 but retained their Royal Navy names and were returned after the war; a fourth ship – ''Loch Fionn'' – was also earmarked for transfer but was retained by the

as a Bay-class frigate. ''Loch Ard'', ''Loch Boisdale'' and ''Loch Cree'' were transferred to South Africa as ''Transvaal'', ''Good Hope'' and ''Natal'' respectively on completion. In 1948, six vessels, including two of the ex-Royal Canadian Navy trio, were refitted from reserve and transferred to New Zealand. During the

Korean War {{Infobox military conflict , conflict = Korean War , partof = the Cold War and the Korean conflict , image = Korean War Montage 2.png , image_size = 300px , caption = Clockwise from top:{ ...

, the Royal Navy reactivated several vessels and transferred them to the

Mediterranean The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on ...

where they released s for war duties. In 1964 ''Loch Insh'' was transferred to Malaysia.

Modifications

''Loch Assynt'' and ''Loch Torridon'' were modified whilst under construction to depot ships for

coastal forces Coastal Forces was a division of the Royal Navy initially established during World War I, and then again in World War II under the command of Rear-Admiral, Coastal Forces. It remained active until the last minesweepers to wear the "HM Coastal Fo ...

, armed with a twin QF Mark XVI on a single mounting Mark XIX forward and six single 20 mm Oerlikons. With the war in the Atlantic won by 1944, and a need forecast for additional fleet A/A escorts for the Royal Navy's increased Far Eastern commitments, twenty-six Loch class were redesigned and renamed (of which nineteen were completed) as Bay-class anti-aircraft frigates. In 1953, seven vessels were modernised; ''Loch Alvie'', ''Loch Fada'', ''Loch Fyne'', ''Loch Insh'', ''Loch Killisport'', ''Loch Lomond'' and ''Loch Ruthven''. The single gun was replaced by the ubiquitous twin mounting HA/LA Mark XIX and the A/A weaponry was standardised as a single twin mounting Mark V and four single mounting Mark VII for the 40 mm Bofors gun, with a Simple Tachymetric Director shipped for the Mark V. Radar Type 277 was fitted with the new ANU antenna array. ''Loch Killisport'' sported a gunshield manufactured from GRP to test this material for suitability of constructing the housing of the new 4.5-inch gun Mark 8. ''Loch Fada'' paid off in 1967 and was used to test an early vertical launch variant of the new

Sea Wolf missile The sea, connected as the world ocean or simply the ocean, is the body of salty water that covers approximately 71% of the Earth's surface. The word sea is also used to denote second-order sections of the sea, such as the Mediterranean Sea, ...

Completed ships

Royal Navy

1942 War Programme (4 ships): 1943 War Programme (26 completed including 2 modified as Coastal Forces Depot Ships): * – built by Smith's Dock, laid down 13 December 1943, launched 7 July 1944 and completed 1 February 1945. Transferred to

Royal New Zealand Navy The Royal New Zealand Navy (RNZN; mi, Te Taua Moana o Aotearoa, , Sea Warriors of New Zealand) is the maritime arm of the New Zealand Defence Force. The fleet currently consists of nine ships. The Navy had its origins in the Naval Defence Act ...

on 28 September 1948 as ''Kaniere''. * – built by Barclay Curle, laid down 31 August 1943, launched 14 April 1944 and completed 21 August 1944; transferred to

Royal Canadian Navy The Royal Canadian Navy (RCN; french: Marine royale canadienne, ''MRC'') is the naval force of Canada. The RCN is one of three environmental commands within the Canadian Armed Forces. As of 2021, the RCN operates 12 frigates, four attack subma ...

on completion, returned to

in 1945. Sold 18 January 1965 in Singapore for breaking up. * – built by Harland & Wolff, laid down 20 January 1944, launched 2 August 1944 and completed 21 May 1945; transferred to South African Navy on completion as . * – built by Caledon Shipbuilding, laid down 1 November 1944, launched 7 June 19445 and completed 17 November 1945. * – built by Swan Hunter, laid down 11 February 1944, launched 14 December 1944 and completed 2 August 1945 as Coastal Forces depot ship ''Derby Haven''. Sold to Iranian Navy in July 1949 as ''Babr''. * – built by Blyth Dry Dock, laid down 8 November 1943, launched 5 July 1944 and completed 1 December 1944; transferred to South African Navy on completion as . * – built by Harland & Wolff, laid down 28 December 1943, launched 23 May 1944 and completed 23 October 1944. Sold 8 July 1963 to break up at Lisbon. * – built by Swan Hunter, laid down 18 October 1943, launched 19 June 1944 and completed 8 March 1945; transferred to South African Navy on completion as . * – built by Burntisland Shipbuilding, laid down 8 December 1943, launched 24 May 1944 and completed 9 November 1944. Sold 7 July 1970 to break up at Newport. * – built by Burntisland Shipbuilding, laid down 29 May 1944, launched 18 October 1944 and completed 23 February 1945. Broken up in November 1957 at Dunston. * – built by Harland & Wolff, laid down 28 December 1943, launched 8 June 1944 and completed 18 December 1944. Sold in September 1961, becoming mercantile ''Orion''. * – built by Henry Robb, laid down 17 November 1943, launched 10 May 1944 and completed 20 October 1944. Transferred to Malaysian Navy 2 October 1964 as ''Hang Tuah''. * – built by Henry Robb, laid down 31 December 1943, launched 21 August 1944 and completed 29 December 1944. Transferred to

in 1949 as ''Rotoiti''. * – built by Burntisland Shipbuilding, laid down 22 June 1943, launched 29 November 1943 and completed 12 April 1944. Broken up in August 1960 at Newport. * – built by Harland & Wolff, laid down 28 December 1943, launched 6 July 1944 and completed 9 July 1945. Sold 20 February 1970 to break up at Blyth. * – built by Caledon Shipbuilding, laid down 7 December 1943, launched 19 June 1944 and completed 16 November 1944. Sold 6 September 1968 to break up at Faslane. * – built by Caledon Shipbuilding, laid down 16 March 1944, launched 3 October 1944 and completed 24 February 1945. Broken up in August 1963 at Inverkeithing. * – built by Swan Hunter, laid down 15 July 1943, launched 25 January 1944 and completed 2 August 1944; transferred to

on completion, returned to

in 1945. Transferred to

on 11 April 1949 as ''Tutira''. * – built by Blyth Dry Dock, laid down 3 December 1943, launched 2 September 1944 and completed 11 January 1945. Broken up in November 1957 at Dunston. * – built by

Charles Hill & Sons Charles Hill & Sons was a major shipbuilder based in Bristol, England, during the 19th and 20th centuries. Background Established in 1845 from the company Hilhouse, they specialised mainly in merchant and commercial ships, but also undertook t ...

, laid down 4 January 1944, launched 3 June 1944 and completed 6 October 1944. Broken up in 1966 at Plymouth. * – built by

, laid down 31 March 1944, launched 9 September 1944 and completed 22 December 1944. Broken up in September 1959 at Genoa. * – built by Swan Hunter, laid down 6 September 1943, launched 23 February 1944 and completed 10 October 1944. Transferred to

on 13 September 1948 as ''Taupo''. * – built by Ailsa Shipbuilding, laid down 30 November 1943, launched 19 October 1944 and completed 22 February 1945. Broken up in September 1959 at Genoa. * – built by Swan Hunter, launched 13 January 1945 and completed 19 October 1945 as Coastal Forces depot ship . Broken up August 1965 at Blyth. * – built by Caledon Shipbuilding, laid down 26 June 1944, launched 12 February 1945 and completed 4 July 1945. Broken up in August 1963 at Bo'ness. * – built by Ailsa Shipbuilding, laid down 30 March 1944, launched 8 October 1945 and completed 13 July 1946. Broken up in August 1965 at Dalmuir.

Transferred ships

Royal Canadian Navy

* * * All three were returned to the Royal Navy in 1945.

South African Navy

* HMSAS ''Good Hope'' (K 432) (ex- HMS ''Loch Boisdale'').

Scuttled Scuttling is the deliberate sinking of a ship. Scuttling may be performed to dispose of an abandoned, old, or captured vessel; to prevent the vessel from becoming a navigation hazard; as an act of self-destruction to prevent the ship from being ...

as an

artificial reef An artificial reef is a human-created underwater structure, typically built to promote marine life in areas with a generally featureless bottom, to control erosion, block ship passage, block the use of trawling nets, or improve surfing. Many ...

in False Bay, 12 December 1978. * HMSAS ''Natal'' (K 10) (ex- HMS ''Loch Cree''). Survey ship 1957. Sunk as a

target Target may refer to: Physical items * Shooting target, used in marksmanship training and various shooting sports ** Bullseye (target), the goal one for which one aims in many of these sports ** Aiming point, in field artillery, fi ...

off the

Cape A cape is a clothing accessory or a sleeveless outer garment which drapes the wearer's back, arms, and chest, and connects at the neck. History Capes were common in medieval Europe, especially when combined with a hood in the chaperon. Th ...

, 19 September 1972. * HMSAS ''Transvaal'' (K 602) (ex- HMS ''Loch Ard''). Scuttled as an artificial reef in False Bay, 3 August 1978.

Royal New Zealand Navy

* (ex- HMS ''Loch Achanalt''). Broken up in January 1966 at Hong Kong. * (ex- HMS ''Loch Achray''). Sold in 1966 for breaking up at Hong Kong. * (ex- HMS ''Loch Katrine''). Sold in November 1966 for breaking up at Hong Kong. * (ex- HMS ''Loch Eck''). Sold in September 1965 for breaking up in Hong Kong. * (ex- HMS ''Loch Shin''). Sold 15 December 1961 for breaking up. * (ex- HMS ''Loch Morlich''). Sold 15 December 1961 for breaking up. Ex-Royal Navy vessels, transferred from 1948.

Royal Malaysian Navy

* ''Hang Tuah'' (ex- HMS ''Loch Insh''). Retired and scrapped in 1977.

Cancelled 54 ships (Royal Navy)

* HMS ''Loch Affric'' (K 601) from Ailsa Shipbuilding, Troon. * HMS ''Loch Clunie'' (K 607) from Ailsa Shipbuilding, Troon. * HMS ''Loch Ericht'' (K 612) from Ailsa Shipbuilding, Troon. * HMS ''Loch Erisort'' (K 613) from Barclay Curle, Glasgow. * HMS ''Loch Garve'' (K 617) from Hall Russell. * HMS ''Loch Griam'' (K 621) from Swan Hunter. * HMS ''Loch Harray'' (K 623) from Smith's Dock. * HMS ''Loch Ken'' (K 626) from Smith's Dock. * HMS ''Loch Kirbister'' (K 629) from Swan Hunter. * HMS ''Loch Linfern'' (K 631) from Smith's Dock. * HMS ''Loch Linnhe'' (K 632) from William Pickersgill. * HMS ''Loch Lyon'' (K 635) from Swan Hunter. * HMS ''Loch Minnick'' (K 637) from Smith's Dock. * HMS ''Loch Nell'' (K 641) from Henry Robb. * HMS ''Loch Odairn'' (K 642) from Henry Robb. * HMS ''Loch Ossian'' (K 643) from Smith's Dock. * HMS ''Loch Ryan'' (K 646) from William Pickersgill. * HMS ''Loch Scrivain'' (K 649) from William Pickersgill. * HMS ''Loch Tanna'' (K 652) from Blyth Dry Dock. * HMS ''Loch Tilt'' (K 653) from William Pickersgill. * HMS ''Loch Urgill'' (K 656) from Blyth Dry Dock. * HMS ''Loch Vennacher'' (K 657) from Blyth Dry Dock. * HMS ''Loch Watten'' (K 659) from Blyth Dry Dock. * HMS ''Loch Awe'' from Harland & Wolff. * HMS ''Loch Badcall'' from William Pickersgill. * HMS ''Loch Caroy'' from William Pickersgill. * HMS ''Loch Doine'' from Smith's Dock. * HMS ''Loch Creran'' from Smith's Dock. * HMS ''Loch Earn'' from

. * HMS ''Loch Enoch'' from Harland & Wolff. * HMS ''Loch Eye'' from Harland & Wolff. * HMS ''Loch Eyenort'' from Harland & Wolff. * HMS ''Loch Glashan'' from Smith's Dock. * HMS ''Loch Goil'' from Harland & Wolff. * HMS ''Loch Hourn'' from Harland & Wolff. * HMS ''Loch Inchard'' from Harland & Wolff. * HMS ''Loch Kirkaig'' from Harland & Wolff. * HMS ''Loch Kishorn'' from Henry Robb. * HMS ''Loch Knochie'' from William Pickersgill. * HMS ''Loch Laro'' from Harland & Wolff. * HMS ''Loch Lurgan'' from Harland & Wolff. * HMS ''Loch Maberry'' from Hall Russell. * HMS ''Loch Ronald'' from Harland & Wolff. * HMS ''Loch Sheallah'' from Harland & Wolff. * HMS ''Loch Shiel'' from Harland & Wolff. * HMS ''Loch Skaig'' from Smith's Dock. * HMS ''Loch Skerrow'' from

. * HMS ''Loch Stemster'' from Harland & Wolff. * HMS ''Loch Stenness'' from Smith's Dock. * HMS ''Loch Striven'' from Harland & Wolff. * HMS ''Loch Sunart'' from Harland & Wolff. * HMS ''Loch Swin'' from Harland & Wolff. * HMS ''Loch Tummell'' from Harland & Wolff. * HMS ''Loch Vanavie'' from Harland & Wolff.

Bibliography

* * ''British and Empire Warships of the Second World War'', H T Lenton, Greenhill Books, * ''Royal Navy Frigates 1945–1983'', Leo Marriott, Ian Allan, 1983,
Uboat.net article on Loch class frigates

External links

The Loch class frigates association
{{DEFAULTSORT:Loch Class Frigate Cold War frigates of South Africa Frigate classes Frigates of the South African Navy Ship classes of the Royal Navy