Dido class cruiser

The Dido class was a class of sixteen (including the Bellona sub-class) light cruisers built for the Royal Navy. The design was influenced by the Arethusa-class light cruisers. The first group of three ships was commissioned in 1940, the second group (six ships) and third group (two ships) were commissioned in 1941–1942. The Bellona-class ships commissioned between 1943 to 1944. Most members of the class were named after figures of Greek mythology.

They were designed as fleet escorts to protect heavier units from both light surface forces and aircraft. The enthusiasm felt for them by the Board of Admiralty was borne out by good results in action and the only real problem with the type was shortage of gun-mountings and a need to stiffen them forward to take the weight of the forward turrets. {| class="toc" id="toc"

Contents
[hide] *1 Armament
 * 2 Service
 * 3 Ship modifications
 * 3.1 Didos
 * 3.2 Bellonas
 * 4 In popular culture
 * 5 Notes
 * 6 References
 * 7 External links
 * }

Armament
 Cleopatra  throws out smoke to shield a convoy as  Euryalus  elevates her forward 5.25 inch guns to shell the Italian Fleet at the Second Battle of Sirte, 22 March 1942The class were intended to be armed with ten 5.25 inch (133 mm) guns in five twin turrets, which were of the same circular design as the secondary armament in the King George V-class battleships. A shortage of the guns, due to difficulties in manufacturing them, led to the first group being armed with only eight 5.25 inch guns in four twin turrets. The fifth twin turret was added later to  Dido  only. The first group was also armed with a 4 inch (102 mm) gun and two quadruple QF 2 pounder (40 mm) "pom-poms".

The second group had the five twin 5.25 inch guns but did not have the 4 in (102 mm) gun. The third group's armament was changed due to the shortage of 5.25 in guns, being armed with eight 4.5 inch (113 mm) guns in four twin turrets instead. The 4.5 inch gun was better suited to the primary anti-aircraft role of the Dido class. The 4.0 inch (102 mm) gun was also fitted and its 2 pounder armament was increased from eight to ten.

The Bellona sub-class differed in appearance somewhat from their predecessors. They had eight 5.25 inch (133 mm) RP10MkII guns in four twin turrets and had vastly improved anti-aircraft armament, with twelve 2 pounder guns and twelve Oerlikon 20 mm cannons. The bridge of the Bellona-class was lowered by one deck compared to the previous three groups, which allowed full radar control to be fitted to the 5.25 inch (133 mm) turrets and 2 pounders, due to the decreased topweight. These ships used the HACS high angle fire control system. The two funnels were more upright than the raked ones of the original Dido-class.

Service
In World War II, the Dido class saw much action, including the battle of Cape Matapan, the Second Battle of Sirte, Operation Torch, Operation Overlord and the battle of Okinawa, as well as many other duties in the Mediterranean and Pacific. The class lost five ships during the war ( Bonaventure ,  Charybdis ,  Hermione ,  Naiad , and  Spartan ); in addition the  Scylla  was badly damaged by a mine and declared a Constructive Total Loss. The post-war survivors continued in service; all were decommissioned by the 1960s.  Bellona ,  Black Prince  and  Royalist  were lent to the Royal New Zealand Navy post-World War II. In 1956,  Diadem  was sold to Pakistan and renamed Babur.

Didos
 Bonaventure  completed with only four twin 5.25 in turrets because of shortages and received a 4 inch starshell gun in X position. She had received a radar set before October 1940 but was otherwise unaltered.

 Naiad  completed with five turrets. She received five single 20 mm in September 1941 and had radar Type 279 by this time.

Phoebe completed with four turrets and was fitted with a 4 inch in Q position forward of the bridge. The latter was landed during her refit between November 1941 and April 1942 at New York, along with the .5 inch machine guns and Type 279 radar, while a quadruple 2 pdr supplanted the 4 inch and eleven single 20 mm guns were fitted. Radars were now Type 281, 284 and 285. The A turret was temporarily removed at the end of 1942 after torpedo damage. During repairs in the first six months of 1943, all three quadruple 2 pdr were landed, as were seven single 20 mm, to be replaced by three quadruple 40 mm Bofors guns and six twin 20 mm. Radar Type 272 was also fitted. A turret was replaced in July 1943. Her light anti-aircraft weaponry in April 1944 was twelve 40 mm (3 × 4) and sixteen 20 mm (6 × 2, 4 xl).

 Dido  had four turrets and a 4 inch similar to Phoebe. The 4 in and the machine guns were removed in the latter half of 1941 at Brooklyn Navy Yard, when Q 5.25 in turret was shipped and five single 20 mm were fitted. In the early summer of 1943 three single 20 mm were exchanged for four twin 20 mm and the radar outfit was altered by the addition of Types 272, 282, 284 and 285. April 1944 lists show only eight 20 mm. The cruisers HMS Edinburgh, HMS Hermione, and HMS Euryalus, steaming in line abreast whilst they escort a convoy as part of Operation Halberd, - convoy not visible. Euryalus  completed with her designed armament. In September 1941 the .5 in MGs were landed and five single 20 mm fitted. Two more were added by September 1942. By mid-1943 two single 20mm had been removed and four twin 20 mm shipped. The type 279 radar was replaced by types 272, 281, 282 and 285. In a long refit from October 1943 to July 1944, Q turret was replaced by a quadruple 2 pdr and two twin 20 mm were fitted. Radar 271 and 272 were removed and types 279b, 277 and 293 fitted.

 Hermione  also completed as a five-turret ship. She had the .5 in MGs removed in October/November 1941 and received five single 20 mm.

Sirius completed with five turrets and five 20 mm. She had received two more 20 mm by mid-1943. One of these was landed at Massawa at the end of 1943 and two 40 mm Bofors Mk III were fitted. She is listed as having only seven 20 mm as light AA in April 1944. By April 1945 she had two Mk III 40 mm fitted and had landed two single 20 mm.

Cleopatra was completed with two 2 pdr in 1942 in lieu of the .5 in MGs but these were removed in the middle of the year and replaced by five 20 mm. A sixth 20 mm was added in mid-1943. During repairs between November 1943 and November 1944, Q turret was removed, as were two quadruple 2 pdr and five 20 mm. Three quadruple 40 mm Bofors and six twin 20 mm were fitted and the singles numbered four.

Argonaut completed with four single 20 mm in lieu of the .5 in MGs. She had Q turret removed during repairs in 1943/44, and lost the four single 20 mm. She received a quadruple 2 pdr in lieu of the 5.25 in, and had five twin 20 mm fitted. By April 1944 her light AA comprised three quadruple 2 pdr, six twin power-operated 20 mm and five single. By the end of the war with Japan she had received five 40 mm Bofors and three single 40 mm Bofors Mk III.

 Scylla  completed with four twin 4.5 in Mk III in UD MK III mountings because of a shortage of 5.25 in mountings. The forward superstructure was considerably modified to accommodate these and also to increase crew spaces. Her light AA on completion was eight single 20 mm. Six twin power-operated 20 mm were added at the end of 1943.

 Charybdis  also completed with four twin 4.5 inch, and had in addition a single 4 in Mk V for-ward of X mounting. Her light AA at completion was four single 20 mm and two single 2 pdr. The 4 inch starshell gun and two single 2 pdr were removed and replaced by two twin and two single 20 mm, probably in 1943.

Bellonas
HMS Diadem of the Bellona sub-classSpartan received no alterations as far as is known.

 Royalist  was converted to an Escort Carrier Squadron flagship immediately on completion, when an extra two twin 20 mm were fitted as well as four single 20 mm. She was the only ship to receive an extensive postwar modernisation. (Loaned to RNZN in 1956, in exchange for Bellona).

 Bellona  had four single 20 mm added by April 1944, and received an extra eight single 20 mm by April 1945. (Loaned to the RNZN after the war).

 Black Prince  and  Diadem  also received eight single 20 mm, and had a further two twin 20 mm by early 1945. (Black Prince was loaned to the RNZN after the war; Diadem was sold to Pakistan in 1956, and was renamed Babur).

In popular culture

 * HMS Ulysses (1955 novel by Alistair Maclean)
 * In the 1953 film of C.S.Forester's Brown on Resolution, (called Sailor of the King in Britain, and Single-handed in the USA), the Dido-class HMS Cleopatra plays both the fictional Royal Navy ships "HMS Amesbury" and "HMS Stratford". As Amesbury she is heroically sunk by the more powerful German raider Essen, (portrayed by HMS Manxman with large mock-up gun turrets), and as Stratford she triumphs at the end of the story. The two battle sequences depict this open-bridge light-cruiser firing her guns and torpedoes in some detail.