A - class destroyer ( 1929 ) The A class was a flotilla of eight destroyer s built for the Royal Navy as part of the 1927 naval programme . A ninth ship , HMS " Codrington " , was built to an enlarged design to act as the flotilla leader . Two similar ships , HMCS " Saguenay " and HMCS " Skeena " , were built for the Royal Canadian Navy . Design . The A class were an Admiralty standard design based on the 1926 prototypes HMS " Amazon " and HMS " Ambuscade " . It was intended that the following alterations be made from the prototypes : 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 with a deep load maximum of only . " 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 hp hour in her sisters to hp hour . In the event the trials were inconclusive , and the Admiralty maintained an attachment to the 300 psi / 600 °F Admiralty boiler until the Battle class of 1942 which entered service in 1944 , some ten years after other major Navies . " Codrington " . HMS " Codrington " was built to an enlarged design - 343 ft ( 105 m ) compared to 320 ft ( 98 m ) - to accommodate Captain ( D ) ( 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 made on trials . However , the increased length made her somewhat unhandy , having a turning circle much greater than the standard A class , which resulted in complicated flotilla manoeuvres . 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 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 , although only slightly . The ships were built by John I . Thornycroft & Company 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 20 cwt anti - aircraft gun on a Mk . IV HA mounting , 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 Oerlikon 20 mm cannon were fitted , one in each bridge wing . " Achates " had ' A ' gun replaced by a Hedgehog anti - submarine ( A / S ) mortar and had the Type 271 centimetric Radar for detecting surfaced U - boat s . Others had a Type 286F or 290 metric Radar 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 , a Type 286 Radar added , no torpedoes , a 12 pdr gun , six single 20 mm Oerlikon guns and stowage for 141 depth charges . By 1943 , " Antelope " had a Type 271 Radar , and Type 286 and 290 sets , where fitted , were replaced with the 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 bridge 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 " received 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 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 " and " Ardent " were sunk on 8 June 1940 by the German battleships " Scharnhorst " and " Gneisenau " west of Narvik during the Norwegian campaign . " Codrington " was sunk by German air attack at Dover on 27 July 1940 . " Acheron " was sunk by a mine off the Isle of Wight on 17 December 1940 . " Achates " was sunk by two large German heavy cruisers , " Admiral Hipper " and " Lützow " . " Arrow " was so badly damaged when the ammunition ship SS " Fort la Monte " blew up on 4 August 1943 at Algiers that she could not be repaired and was towed to Taranto and paid off . " Skeena " was wrecked in a storm off Iceland on 25 October 1944 . " Saguenay " was heavily damaged in a collision with the merchant ship " Azara " and was consigned to the role of a training ship after being repaired . The surviving ships were worn out from war duties and were scrapped soon after the war . See also . A class destroyer ( 1913 ) - a previous group of Royal Navy destroyers also known as the " A class " .