HMS cruiser Manchester

The Southampton class cruisers mark the culminating point of a decade of indecjsion over British cruiser-design. As we have seen, the cumulative effect of the Washington and London Naval Treaties, as far as the cruiser was concerned, was to produce ships built to the maximum size, and even above the maximum in some cases. From the 10,000-ton 8-inch gun 'Counties' the British went to the 8,000-ton Yorks, then to the 7,000-ton Leanders with 6-inch guns; then came a further reduction, the 5,000-ton Arethusas. But as soon as these excellent ships appeared the Admiralty announced the building of anew series of 10,000-ton cruisers, but armed this time with nothing bigger than 6-inch guns.
After all the arguments that had raged about the cost of big cruisers this choice of maximum size seems illogical, and a word of explanation is needed.

The Japanese Mogami class cruisers were begun in 1931, and ostensibly managed to mount fifteen 6.1-inch guns on a displacement of only 8,500 tons. These in turn inspired the American Brooklyn class of similar power, while their British contemporaries, the Leanders could only muster eight 6-inch on 7 ,000 tons.
The British 8-inch cruisers could deal with the Mogamis, but they were already committed to dealing with the powerful Japanese 8-inch gun cruisers, a task which would have tested them severely.

As a result of the disparity between British and foreign designs (in 1933 war between the United States and Great Britain was not quite as unthinkable as it becane three or four years later) the Admiralty decided to match the Brooklyns and Mogamis with new big cruisers to be known as the Polyphemus class.
Quite apart from the fact that designed opponents never met in battle (cf. the London) the folly of being stampeded into building these ships was amply rewarded when the British learned in 1945 that not only had the Japanese lied iiJout the Mogamis (their true displacement was 12,400 tons), but they had also converted them into heavy cruisers in the late thirties by the simple expedient of replacing the five triple 6.1 inch turrets by twin 8-inch guns.

The new 10,000-ton cruisers were basically an expansion of the successful "Modified Leander" type which evolved from the single-funnelled Leander type (see Ajax). To minimise battle damage as in the Amphions the four boilers were split into two units, and placed alternately to the engine-rooms. This arrangement used more deck-space but it had the effect of ensuring that half the engine-power could survive a torpedo-hit, and proved effective in many ships during World War II. To match the Mogami and Brooklyn triple 6-inch guns replaced the twin mountings of the Amphion type thus ensuring a broadside of some 5,000 Ibs. per minute.

Critics of the design immediately pointed out that the American and Japanese cruisers had an additional triple turret on the same tonnage or even 15 per cent less. In the case of the Mogami this disparity can be dismissed as laughable, since it should have been obvious to technical experts that such an armament was unlikely on a light displacement. The Americans at least admitted to 10,000 tons for the Brooklyn, but as her additional 6-inch turret was sited very awkwardly, much as the third turret in the Nelson and Rodney (and similar to the Mogamj) it was hardly worth the extra weight and length of hull needed to work it in. It was later learned that the Mogami opened her seams during broadside firing due to defective welds, and had to have extra stiffening rivetted in place. As freeboard was already low this extra weight reduced stability even further, and the, last two of the class were redesigned without any after turrets.

The first names chosen for the new British cruisers were those of mythological monsters, Polyphemus and Minotaur, but before these two were completed they and their sisters were given a series of good "town" names, commemorating earlier cruisers in most cases. The first five were built under the 1933 and 1934 Estimates, and a urther three improved vis were laid down under the 1935 and 1936 Estimates including Manchester herself. These "Later Southhampton" type ships differed from the earlier ships in having slightly bigger hulls, more horsepower and a series of minor modifications to fittings.

The Southamptons were the first British cruisers designed with fixed aircraft catapults and hangars. Since World War Ian increasing amount of ingenuity had been devoted to finding ways of operating reconnaisance aircraft from ships, and it now seems that much of it was wasted since the function should have been delegated to carrier-aircraft. The Americans opted for a sensible solution to the problem in the Brooklyn by incorporating the hangar in a large square stern, where a fire from petrol vapour could do least damage. The British, however, as their cruisers lacked the flush deck and transom stern necessary, sited their hangars on either side of the forefunnel, which in effect cut the topsides into separate areas, and put a potential fire hazard too close to the vital commandcentre of bridge and directors.

The decision to include two large hangars in the Southampton design had another undesirable effect. Dividing the topsides meant that the four twin anti-aircraft mountings had to be concentrated amidships, and the quadruple pom-poms could only be sited on the roofs of the hangars. In practice this meant that the anti-aircraft battery had a significant lack of overlap both forward and aft, and one can fairly say that subsequent wartime modifications to the class were largely efforts to remedy this deficiency.

The drawing shows Manchester at the time of her loss, during the great "Pedestal" convoy to Malta in August 1942. She has had radar added to control 6-inch guns (Type 284, on main director), 4-inch (Type 285 on high-angle directors) and multiple pom-poms (Type 282). In addition she has Type 279 Air Warning at the mastheads and a Type 273 Surface Warning set with its distinctive lantern housing between the main director and the foremast.

20-mm Oerlikon guns have been added on either side of the bridge, and also on the after superstructure, the roof of 'X' turret and on the quarterdeck. Owing to the pitch of the 6-inch turret roof the Oerlikon gun-position has had to be offset.
Note particularly the addition of an Army-type 40-mm Bofors gun on 'B' turret; this weapon was so highly valued that it was allocated its own controlling officer in action.

As they were SO modern the Southampton class underwent only slight modification until the end of the War. As can be seen on the drawing, apart from the addition of light anti-aircraft guns, Manchester has changed little. The office for the Air Warning Type 279 radar set has been added at the after end of the bridge, and the lantern and offire for the Type 273 set occupy the space between the director and the mast. The most interesting addition is the inclination baffle fitted on the rear side of the first funnel; this device made the funnel appear vertical, and thus made the ship's course difficult to judge from any angle.

The boats carried include two 27-ft. whalers, two 35-ft. fast pinnaces, a 36-ft.
motor pinnace, a 25-ft. fast motor boat and a 16-ft. motor dinghy. An additional pair of 32-ft. cutters are stowed out of sight between the after funnel and mainmast, in a well beneath the pinnaces; the upper boats are stowed on skid beams over this well. The "Walrus" amphibian aircraft are still carried, and the four-barrelled pom-DOms can be seen on the hangar roof. Note also the three 44-inch searchlights carried.

The minor differences which distinguished the Manchester, Liverpool and Gloucester from the earlier Southamptons can be seen clearly. The bridge front is rounded, in place of the flat curve in the first five. To improve anti-aircraft fire-control additional high-angle and main armament directors were worked in at the after end of the superstructure. The'other improvement was the provision of shelters for the crews of the 4-inch guns' crews placed between the mountings.
This simple innovation did much to improve the efficiency of gun-crews, who had to spend many hours closed up at their guns,and it was extended to the earlier vessels  as the war progressd.