The A class was a flotilla

Ship class

A ship class is a group of ships of a similar design. This is distinct from a ship-type, which might reflect a similarity of tonnage or intended use. For example, the is a nuclear aircraft carrier of the Nimitz class....

 of eight destroyer

Destroyer

In naval terminology, a destroyer is a fast and maneuverable yet long-endurance warship intended to escort larger vessels in a fleet, convoy or battle group and defend them against smaller, powerful, short-range attackers. Destroyers, originally called torpedo-boat destroyers in 1892, evolved from...

s built for the Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 as part of the 1927 naval programme. A ninth ship, Codrington

HMS Codrington (D65)

HMS Codrington was an A-class destroyer of the Royal Navy. She served as the flotilla leader during the Second World War in Home waters and off the Norwegian coast, before being bombed and sunk on 27 July 1940 whilst in dock at Dover....

, was built to an enlarged design to act as the flotilla leader

Flotilla leader

A flotilla leader was a warship suitable for commanding a flotilla of destroyers or other small warships, typically a small cruiser or a large destroyer...

. Two similar ships, Saguenay

HMCS Saguenay (D79)

HMCS Saguenay was a River-class destroyer that served in the Royal Canadian Navy from 1931-1945.She was similar to the Royal Navy's A-class and initially wore the pennant D79, changed in 1940 to I79....

 and Skeena

HMCS Skeena (D59)

HMCS Skeena was a River-class destroyer that served in the Royal Canadian Navy from 1931-1945.She was similar to the Royal Navy's A-class and wore initially the pennant D59, changed in 1940 to I59....

, were built for the Royal Canadian Navy

Royal Canadian Navy

The history of the Royal Canadian Navy goes back to 1910, when the naval force was created as the Naval Service of Canada and renamed a year later by King George V. The Royal Canadian Navy is one of the three environmental commands of the Canadian Forces...

.

Design

The A class were an Admiralty

Admiralty

The Admiralty was formerly the authority in the Kingdom of England, and later in the United Kingdom, responsible for the command of the Royal Navy...

 standard design based on the 1926 prototypes Amazon

HMS Amazon (D39)

HMS Amazon was a prototype design of destroyer ordered for the Royal Navy in 1924. She was designed and built by Thornycroft in response to an admiralty request for a new design of destroyer incorporating the lessons and technological advances of the First World War...

 and Ambuscade

HMS Ambuscade (D38)

HMS Ambuscade was a British Royal Navy destroyer which served in the Second World War. She and her Thornycroft competitor, Amazon, were prototypes designed to exploit advances in construction and machinery since World War I and formed the basis of Royal Navy destroyer evolution up to the Tribal...

. It was intended that the following alterations be made from the prototypes;

• The guns were to be true Quick Firing (QF) pieces with full length shields, those in Amazon and Ambuscade were of the Breech Loading (BL) type, with two-part ammunition.
• 'B' gun was to be carried on a High-Angle (HA) mounting giving 60° elevation
• The torpedo tubes were to be quadruple instead of triple
• Asdic (sonar)
  Sonar
  Sonar is a technique that uses sound propagation to navigate, communicate with or detect other vessels...
  
  , depth charges and high-speed destroyer minesweeps were to be carried
• The separate cruising steam turbine
  Steam turbine
  A steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into rotary motion. Its modern manifestation was invented by Sir Charles Parsons in 1884....
  
  s were to be replaced by adding a cruising stage to the main turbine
• A petrol generator was to be fitted, so that electric light and services could be provided when steam was down in harbour

In the event, the HA mounting was never fitted, along with the Asdic and most of the depth charges. The class were 200 tons heavier than the 1926 prototypes yet the only major improvement were the quadruple tubes. Speed was disappointing, being 35 knots (68.6 km/h) with a deep load maximum of only 31 knots (60.8 km/h).

Acheron was given high temperature and pressure boilers (500 psi, 750 ° F) by Parsons Marine Steam Turbines to examine the weight and economy savings. Her specific fuel consumption was reduced from 0.8 lb (0.362873896 kg) ⁻¹ hp⁻¹ hour⁻¹ in her sisters to 0.6 lb (0.272155422 kg) ⁻¹ hp⁻¹ hour⁻¹. In the event the trials were inconclusive, and the Admiralty maintained an attachment to 300 psi / 600 °F until the Battle class

Battle class destroyer

The Battle class were a class of destroyers of the British Royal Navy and Royal Australian Navy . Built in three groups, the first group were ordered under the 1942 naval estimates. A modified second and third group, together with two ships of an extended design were planned for the 1943 and 1944...

 of 1942 which entered service in 1944, some ten years after other major Navies.

Codrington

Codrington was built to an enlarged design - 343 ft (105 m) compared to 320 ft (98 m) - to accommodate Captain (D)

Captain (D)

In the Royal Navy, a Captain is an appointment of a commander of a destroyer flotilla....

 (in Royal Navy parlance, the commander of the destroyer flotilla) and his staff; some 47 additional officers and men. She shipped a fifth 4.7 in gun between the funnels, and with 39000 shp made 37.7 knots (73.9 km/h) on trials. However, the increased length made her somewhat unhandy, having a turning circle much greater than the standard A class, making flotilla manoeuvres complicated.

Canadian ships

The two Canadian ships were designed to be of a similar performance and specification to the British ships to allow them to tactically combine. They had their bows strengthened with heavier plating to enable them to perform in areas with ice, with a large metacentric height

Metacentric height

The metacentric height is a measurement of the static stability of a floating body. It is calculated as the distance between the centre of gravity of a ship and its metacentre . A larger metacentric height implies greater stability against overturning...

 to allow for the build up of ice and snow on the upperworks. Their length was three feet less than their British counterparts, and their displacement also decreased, though only slightly. The ships were built by John I. Thornycroft & Company

John I. Thornycroft & Company

John I. Thornycroft & Company Limited, usually known simply as Thornycroft was a British shipbuilding firm started by John Isaac Thornycroft in the 19th century.-History:...

 in Woolston, Hampshire and had the broad, slab-sided funnels characteristic of that builder.

War modifications

It is unlikely that the early war losses Codrington, Acasta, Acheron and Ardent received any major alterations. In 1941 the surviving ships had the after funnel cut down in height and the after torpedo tubes replaced by a First World War era QF 3 inch 20 cwt anti-aircraft gun on mounting HA Mk. IV; a somewhat token addition. More of an improvement was landing 'Y' gun and the minesweeps and fitting Asdic and racks and throwers for a 10-pattern depth charge salvo, 70 rounds being carried. Two 20 mm Oerlikon guns

Oerlikon 20 mm cannon

The Oerlikon 20 mm cannon is a series of autocannons, based on an original design by Reinhold Becker of Germany, very early in World War I, and widely produced by Oerlikon Contraves and others...

 were fitted, one in each bridge wing. Achates had 'A' gun replaced by a Hedgehog

Hedgehog (weapon)

The Hedgehog was an anti-submarine weapon developed by the Royal Navy during World War II, that was deployed on convoy escort warships such as destroyers to supplement the depth charge. The weapon worked by firing a number of small spigot mortar bombs from spiked fittings...

 anti-submarine (A/S) mortar and had the centimetric Radar Type 271 for detecting surfaced U-boat

U-boat

U-boat is the anglicized version of the German word U-Boot , itself an abbreviation of Unterseeboot , and refers to military submarines operated by Germany, particularly in World War I and World War II...

s. Others had metric Radar Type 286F or 290 added, the former of which had a fixed antennae array and required the ship to be turned to change the bearing down which it scanned. By 1942, the Canadian ships generally had 'B' and 'Y' guns removed, Radar Type 286 added, no torpedoes, a 12 pdr gun, six single 20 mm Oerlikon guns and stowage for 141 depth charges.

By 1943, Antelope had Radar Type 271, and Type 286 and 290 sets, where fitted, were replaced with Type 291. The 12 pounder gun was removed around 1943 and High Frequency Direction Finding (HF/DF, or "huff-duff") was generally added. The single 20 mm guns in the wings were replaced by Mark V powered mountings for twin weapons, the singles replacing the ancient 2 pounder guns amidships. In 1944 Active, Anthony and Antelope receiving a pair of 6 pounder / 10 cwt QF Mark I guns on a Mark I* mounting in lieu of 'B' gun. This automatic weapon was fitted for dealing with E-boat

E-boat

E-boats was the designation for Motor Torpedo Boats of the German Navy during World War II. It is commonly held that the E stood for Enemy....

s on east coast duties.

Service

The class saw much service in the Second World War, being involved in convoy protection and anti-submarine warfare in home waters and the North Atlantic. Seven of the eleven ships of the class were sunk in World War II. Acasta

HMS Acasta (H09)

HMS Acasta , the third ship to bear that name, launched in 1929, was an A-class destroyer built for the Royal Navy. She served in the Second World War and was sunk on 8 June 1940 in action against the German warships and , while escorting the aircraft carrier...

 and Ardent

HMS Ardent (H41)

HMS Ardent was an A-class destroyer of the Royal Navy. She served during the Second World War in Home waters and off the Norwegian coast, before becoming an early war loss when she was sunk by the German warships and on 8 June 1940 whilst escorting the aircraft carrier .-Construction and...

 were sunk on 8 June 1940 by Scharnhorst

German battleship Scharnhorst

Scharnhorst was a German capital ship, alternatively described as a battleship and battlecruiser, of the German Kriegsmarine. She was the lead ship of her class, which included one other ship, Gneisenau. The ship was built at the Kriegsmarinewerft dockyard in Wilhelmshaven; she was laid down on 15...

 and Gneisenau

German battleship Gneisenau

Gneisenau was a German capital ship, alternatively described as a battleship and battlecruiser, of the German Kriegsmarine. She was the second vessel of her class, which included one other ship, Scharnhorst. The ship was built at the Deutsche Werke dockyard in Kiel; she was laid down on 6 May 1935...

 west of Narvik

Narvik

is the third largest city and municipality in Nordland county, Norway by population. Narvik is located on the shores of the Narvik Fjord . The municipality is part of the Ofoten traditional region of North Norway, inside the arctic circle...

 during the Norwegian campaign

Norwegian Campaign

The Norwegian Campaign was a military campaign that was fought in Norway during the Second World War between the Allies and Germany, after the latter's invasion of the country. In April 1940, the United Kingdom and France came to Norway's aid with an expeditionary force...

. Codrington was sunk by German air attack at Dover

Dover

Dover is a town and major ferry port in the home county of Kent, in South East England. It faces France across the narrowest part of the English Channel, and lies south-east of Canterbury; east of Kent's administrative capital Maidstone; and north-east along the coastline from Dungeness and Hastings...

 on 27 July 1940. Acheron

HMS Acheron (H45)

HMS Acheron was an A-class destroyer of the Royal Navy. She served during the Second World War in Home waters and off the Norwegian coast, before becoming an early war loss when she sank after hitting a mine off the Isle of Wight on 17 December 1940...

 was sunk by a mine off the Isle of Wight

Isle of Wight

The Isle of Wight is a county and the largest island of England, located in the English Channel, on average about 2–4 miles off the south coast of the county of Hampshire, separated from the mainland by a strait called the Solent...

 on 17 December 1940. Achates

HMS Achates (H12)

HMS Achates was an A-class destroyer of the British Royal Navy launched on 4 October 1929 and commissioned on 27 March 1930. She was sunk on 31 December 1942 in the Battle of the Barents Sea.-Battle of the Denmark Strait:...

 was sunk by two large German heavy cruisers Admiral Hipper

German cruiser Admiral Hipper

Admiral Hipper, the first of five ships of her class, was the lead ship of the Admiral Hipper–class of heavy cruisers which served with the German Kriegsmarine during World War II. The ship was laid down at the Blohm & Voss shipyard in Hamburg in July 1935 and launched February 1937; Admiral Hipper...

 and Lützow

German pocket battleship Deutschland

Deutschland was the lead ship of her class of heavy cruisers which served with the Kriegsmarine of Nazi Germany during World War II. Ordered by the Weimar government for the Reichsmarine, she was laid down at the Deutsche Werke shipyard in Kiel in February 1929 and completed by April 1933...

. Arrow

HMS Arrow (H42)

HMS Arrow was an A class destroyer of the Royal Navy. She served during the Second World War before being damaged while fighting a fire on an ammunition ship and written off in 1943.-Construction and commissioning:...

 was so heavily damaged when the ammunition ship Fort la Monte blew up on 17 October 1944 at Algiers

Algiers

' is the capital and largest city of Algeria. According to the 1998 census, the population of the city proper was 1,519,570 and that of the urban agglomeration was 2,135,630. In 2009, the population was about 3,500,000...

 that she could not be repaired and was towed to Taranto

Taranto

Taranto is a coastal city in Apulia, Southern Italy. It is the capital of the Province of Taranto and is an important commercial port as well as the main Italian naval base....

 and paid off. Skeena was wrecked in a storm off Iceland

Iceland

Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...

 on 25 October 1944. Saguenay was heavily damaged in a collision with the merchant ship Azara and was consigned to the role of training ship after being repaired.

The surviving ships were worn out from war duties and were scrapped soon after the war.

Ships

Pennant number Pennant number In the modern Royal Navy, and other navies of Europe and the Commonwealth, ships are identified by pennant numbers...	Name	Builder	Laid down	Launched	Commissioned	Fate
Royal Navy
D65	Codrington HMS Codrington (D65) HMS Codrington was an A-class destroyer of the Royal Navy. She served as the flotilla leader during the Second World War in Home waters and off the Norwegian coast, before being bombed and sunk on 27 July 1940 whilst in dock at Dover....	Swan Hunter & Wigham Richardson, Wallsend Wallsend Wallsend is an area in North Tyneside, Tyne and Wear, England. Wallsend derives its name as the location of the end of Hadrian's Wall. It has a population of 42,842.-Romans:...	1928-06-20	1929-08-07	1930-06-04	Bombed and sunk off Dover Dover Dover is a town and major ferry port in the home county of Kent, in South East England. It faces France across the narrowest part of the English Channel, and lies south-east of Canterbury; east of Kent's administrative capital Maidstone; and north-east along the coastline from Dungeness and Hastings...  1940-07-27
H09	Acasta HMS Acasta (H09) HMS Acasta , the third ship to bear that name, launched in 1929, was an A-class destroyer built for the Royal Navy. She served in the Second World War and was sunk on 8 June 1940 in action against the German warships and , while escorting the aircraft carrier...	John Brown & Company John Brown & Company John Brown and Company of Clydebank was a pre-eminent Scottish marine engineering and shipbuilding firm, responsible for building many notable and world-famous ships, such as the , the , the , the , the , and the... , Clydebank Clydebank Clydebank is a town in West Dunbartonshire, in the Central Lowlands of Scotland. Situated on the north bank of the River Clyde, Clydebank borders Dumbarton, the town with which it was combined to form West Dunbartonshire, as well as the town of Milngavie in East Dunbartonshire, and the Yoker and...	1928-08-13	1929-08-08	1930-02-11	Sunk by German battleships Scharnhorst German battleship Scharnhorst Scharnhorst was a German capital ship, alternatively described as a battleship and battlecruiser, of the German Kriegsmarine. She was the lead ship of her class, which included one other ship, Gneisenau. The ship was built at the Kriegsmarinewerft dockyard in Wilhelmshaven; she was laid down on 15...  and Gneisenau German battleship Gneisenau Gneisenau was a German capital ship, alternatively described as a battleship and battlecruiser, of the German Kriegsmarine. She was the second vessel of her class, which included one other ship, Scharnhorst. The ship was built at the Deutsche Werke dockyard in Kiel; she was laid down on 6 May 1935...  off Narvik Narvik is the third largest city and municipality in Nordland county, Norway by population. Narvik is located on the shores of the Narvik Fjord . The municipality is part of the Ofoten traditional region of North Norway, inside the arctic circle... , 1940-06-08
H12	Achates HMS Achates (H12) HMS Achates was an A-class destroyer of the British Royal Navy launched on 4 October 1929 and commissioned on 27 March 1930. She was sunk on 31 December 1942 in the Battle of the Barents Sea.-Battle of the Denmark Strait:...	John Brown	1928-09-11	1929-10-04	1930-02-11	Sunk by German cruiser Hipper German cruiser Admiral Hipper Admiral Hipper, the first of five ships of her class, was the lead ship of the Admiral Hipper–class of heavy cruisers which served with the German Kriegsmarine during World War II. The ship was laid down at the Blohm & Voss shipyard in Hamburg in July 1935 and launched February 1937; Admiral Hipper...  in Battle of the Barents Sea Battle of the Barents Sea The Battle of the Barents Sea took place on 31 December 1942 between German surface raiders and British ships escorting convoy JW 51B to Kola Inlet in the USSR. The action took place in the Barents Sea north of North Cape, Norway... , 1942-12-31
H14	Active HMS Active (H14) HMS Active, the tenth Active , launched in 1929, was an A class destroyer. She served in World War II, taking part in the sinking of four submarines. She was broken up in 1947....	Hawthorn Leslie & Company, Hebburn Hebburn Hebburn is a small town situated on the south bank of the River Tyne in North East England, sandwiched between the towns of Jarrow and Bill Quay...	1928-07-10	1929-07-09	1930-02-09	Sold for breaking 1947-07-07
H36	Antelope HMS Antelope (H36) HMS Antelope was a British A-class destroyer. She was completed 20 March 1930 and assigned to the 18th Destroyer Flotilla, Channel Force, Home Fleet....	Hawthorn Leslie	1928-07-11	1929-07-27	1930-02-20	Sold for breaking 1946-01-28
H40	Anthony HMS Anthony (H40) HMS Anthony was an A-class destroyer of the Royal Navy. She served during the Second World War.-Construction and commissioning:Anthony was ordered from Scotts Shipbuilding and Engineering Company, Greenock, Scotland on 6 March 1928 under the 1927 Programme...	Scotts Shipbuilding & Engineering Company, Greenock Greenock Greenock is a town and administrative centre in the Inverclyde council area in United Kingdom, and a former burgh within the historic county of Renfrewshire, located in the west central Lowlands of Scotland...	1928-07-30	1929-04-24	1930-02-14	Sold for breaking 1948-02-21
H41	Ardent HMS Ardent (H41) HMS Ardent was an A-class destroyer of the Royal Navy. She served during the Second World War in Home waters and off the Norwegian coast, before becoming an early war loss when she was sunk by the German warships and on 8 June 1940 whilst escorting the aircraft carrier .-Construction and...	Scotts	1928-07-30	1929-06-26	1930-04-14	Sunk by German battleships Scharnhorst and Gneisenau off Narvik, 1940-06-08
H42	Arrow HMS Arrow (H42) HMS Arrow was an A class destroyer of the Royal Navy. She served during the Second World War before being damaged while fighting a fire on an ammunition ship and written off in 1943.-Construction and commissioning:...	Vickers Armstrongs, Barrow-in-Furness Barrow-in-Furness Barrow-in-Furness is an industrial town and seaport which forms about half the territory of the wider Borough of Barrow-in-Furness in the county of Cumbria, England. It lies north of Liverpool, northwest of Manchester and southwest from the county town of Carlisle...	1928-08-20	1929-08-22	1930-04-14	Damaged by explosion of SS Fort Lamontee in Algiers Algiers ' is the capital and largest city of Algeria. According to the 1998 census, the population of the city proper was 1,519,570 and that of the urban agglomeration was 2,135,630. In 2009, the population was about 3,500,000...  1943-08-04 and written off as constructive total loss
H48	Acheron HMS Acheron (H45) HMS Acheron was an A-class destroyer of the Royal Navy. She served during the Second World War in Home waters and off the Norwegian coast, before becoming an early war loss when she sank after hitting a mine off the Isle of Wight on 17 December 1940...	John I. Thornycroft & Company John I. Thornycroft & Company John I. Thornycroft & Company Limited, usually known simply as Thornycroft was a British shipbuilding firm started by John Isaac Thornycroft in the 19th century.-History:... , Woolston	1928-08-20	1929-08-22	1930-04-14	Mined off Isle of Wight Isle of Wight The Isle of Wight is a county and the largest island of England, located in the English Channel, on average about 2–4 miles off the south coast of the county of Hampshire, separated from the mainland by a strait called the Solent... , 1940-12-17
Royal Canadian Navy
D79	Saguenay HMCS Saguenay (D79) HMCS Saguenay was a River-class destroyer that served in the Royal Canadian Navy from 1931-1945.She was similar to the Royal Navy's A-class and initially wore the pennant D79, changed in 1940 to I79....	Thornycroft	1929-09-27	1930-07-11	1931-05-22	Damaged in collision 1942-11-15 and de-rated to training ship, sold for breaking 1945
D59	Skeena HMCS Skeena (D59) HMCS Skeena was a River-class destroyer that served in the Royal Canadian Navy from 1931-1945.She was similar to the Royal Navy's A-class and wore initially the pennant D59, changed in 1940 to I59....	Thornycroft	1929-10-14	1930-10-10	1931-06-10	Wrecked in Kollafjord, Iceland, 1944-10-25

See also

A class destroyer (1913)

A class destroyer (1913)

The A class as designated in 1913 was a heterogeneous group of torpedo boat destroyers built for the Royal Navy in the mid-1890s. Some 42 vessels were constructed to the individual designs of their builders to meet Admiralty specifications, the only uniting feature being a specified top speed of...

- a previous group of Royal Navy destroyers also known as the "A class".