The Cruiser (part 4): US heavy cruisers

USS NorthamptonThe Americans disposed of most of their World War I cruisers during the 1920s and 1930s, but at the time of the USA’s entry into World War II as a result of the Japanese attack on Pearl Harbor in December 1941 the Americans had a total of 37 cruisers in the form of 18 heavy cruisers and 19 light cruisers. The size of this total was fortunate, for after the Japanese attack on Pearl Harbor and the loss, permanent or temporary, of many of its battleships, the US Navy in general and its Pacific Fleet in particular was forced to rely on its cruiser force as its primary surface warfare capability at a time when the surviving battleships were used for the escort of vital troop convoys. The intensity of this surface warfare in the period up to the middle of 1943 is attested by the fact that all of the pre-war cruisers involved in the protracted Solomons campaign (August 1942/February 1943) were either sunk or damaged, and after the middle of 1943 the surviving cruisers were generally used for the gunfire support of amphibious landing and for the escort of carrier task forces.

In common with their British counterparts, the American cruisers exploited every extensive stay in port, either for refit or repair, for enhancement of their fighting capabilities: radar was fitted and the anti-aircraft armament was considerably enhanced by the adoption of both greater firepower and specialised fire-control systems. The former was based on the lighter type of weapons (of 20- and 40-mm calibres for the most part) designed to provide a high volume of fire for short-range defence against mass air attacks. The type of enhancement provided in cruisers, which played a key part in US naval thinking in World War II, is exemplified by the revisions to the ‘Northampton’ class ships, which each received 16 40-mm guns in four quadruple mountings and about 27 20-mm cannon in single mountings.

The addition of so much additional topweight sometimes led to a severe loss of stability, but even so the ships displayed a remarkable ability to survive battle damage. This was a testament to the ships’ good basic design and excellent construction, which emphasised extreme sturdiness. Even so, there were some structural failures as a result of poor welding: for example, Pittsburgh lost 90 ft (27.4 m) of her bow in a typhoon after the failure of a poor weld.

In common with most other navies of the period, the US Navy standardised two types of cruiser during the 1920s. These were the heavy cruiser with an armament of 8-in (203-mm) guns and moderately thick armour, and the light cruiser with an armament of 6-in (152-mm) guns and comparatively thin armour. The oldest class of heavy cruiser to see service during World War II was the ‘Pensacola’ class, whose two units were launched in 1929. These were built in accordance with the dictates of the Washington Naval Treaty and were flush-decked ships with a low freeboard. The USA was the last of the treaty signatories to start on the construction of new heavy cruisers, and was therefore able to capitalise on its perceptions of the heavy cruisers that had already been built by other signatories: the French and Italians had both opted for high speed at the expense of protection in the ‘Duquesne’ and ‘Trento’ class ships respectively. The Japanese had been influenced by initial reports of very heavy gun armament on proposed US ships and had therefore opted for an additional main gun turret as well as good protection and a high turn of speed in the ‘Myoko’ class that in fact exceeded the treaty displacement limit by some 1,000 tons. The British had in the ‘Kent’ class decided for a design that was altogether lighter than its contemporaries in firepower, protection and speed but which, as events were to prove, was extremely robustly built and possessed excellent sea-keeping qualities. After assessing these classes, the Americans opted for an approach similar to that of the Japanese with a main armament of 10 8-in (203-mm) guns located not in five twin turrets, as in the Japanese ships, but in super-firing pairs of triple and twin turrets located fore and aft of the superstructure. This primary armament was complemented by eight 5-in (127-mm) dual-purpose guns in single mountings, and the other details of these ships included a full-load displacement of 12,050 tons, protection in the form of a 3-in (76-mm) belt and 2-in (51-mm) deck, and a speed of 32.5 kt on the 107,000 hp (79780 kW) delivered to four shafts by steam turbines. A notable feature of the basic design was the considerable weight saving that the Americans managed to achieve in the design and construction of these fine ships, which had a displacement some 900 tons under the treaty standard displacement limit of 10,000 tons and therefore represented better value than the considerably heavier Japanese ships.

USS PensacolaThe ‘Pensacola’ class set the pattern for the following heavy cruiser classes, which began with the six ships of the ‘Northampton’ class launched in 1929 and 1930. This class was in effect a development of the ‘Pensacola’ class with a raised forecastle for improved seaworthiness and reduced wetness forward, and with further weight saving effected by the replacement of the ‘Pensacola’ class’s primary armament of 10 8-in (203-mm) guns in four turrets with a primary armament of nine 8-in (203-mm) guns in three triple turrets located as a super-firing pair forward and a single turret aft. The ships initially displayed a tendency toward severe rolling, but this was cured by the installation of deeper bilge keels, and the primary details off these ships included a full-load displacement of some 12,250 tons, armament of nine 8-in (203-mm) guns and eight 5-in (127-mm) dual-purpose guns, protection in the form of a 3-in (76-mm) belt and 2-in (51-mm) deck, and speed of 32.5 kt on the 107,000 hp (79780 kW) delivered to four shafts by steam turbines.

The sea battles fought around the Solomon Islands during the second half of 1942 comprised a bloody series of six short, sharp engagements that were often dominated by cruisers. The battles often took place at night as the Japanese believed that they had a decisive advantage in night fighting. The early stages of the fighting for the island of Guadalcanal, on which the Japanese had landed during July 1942, were characterised by serious setbacks for US and Australian naval forces in several stunning blows, particularly in the Battle of Savo Island on the night of 8/9 August 1942. After the strategic defeat of the Japanese in the Battle of Midway in June 1942, the Americans switched over to the offensive in the Pacific. This resulted, among other operations, in the landing on Guadalcanal and neighbouring Tulagi islands as a first stage in the reconquest of the Solomons. The 1st Marine Division landed on 7 August, and within hours gained control over the yet poorly established Japanese garrison. This early example of an amphibious assault entailed the presence offshore of a considerable number of transports, which would need an estimated four days to discharge. In addition to local naval cover, the ships of the American invasion force had the distant support of Vice Admiral Frank J. Fletcher’s carrier task force. These three carriers comprised virtually all the flight decks remaining to the USA in the Pacific theatre and, anxious not to hazard them a moment longer than necessary, Fletcher decided to withdraw after only 36 hours. Initially off-balance at the time of the American landings, the Japanese reacted swiftly.

Vice Admiral Gunichi Mikawa departed from Rabaul within hours of the American landing to cover the 700 miles (1125 km) to Guadalcanal with a force centred on his flagship, the heavy cruiser Chokai, and including two light cruisers and a destroyer. By 14.00 hours the Japanese squadron had covered 200 miles (320 km) and rendezvoused near Bougainville with a powerful reinforcement of four more heavy cruisers. Pressing on to the south-east, Mikawa used the passage between the double island chain of the Solomons, a passage that was soon to become known as ‘The Slot’. The north-west was the direction from which the Americans expected any Japanese riposte to come, and they had therefore covered this quadrant with reconnaissance flights, which twice spotted the advancing Japanese ships during the morning of 8 August. The reconnaissance reports were poorly worded and took considerable time to trickle though the official system, so Rear Admiral Richmond K. Turner, commanding the amphibious force, learned on between 18.00 and 19.00 hours that a Japanese force was approaching and also that Fletcher’s carriers were leaving. The latter was alarming, but the former was not treated with undue concern as the report indicated that the enemy force consisted largely of seaplane tenders: this accorded fully with the type of base that the Japanese had been establishing on Tulagi, and such ships posed no direct threat. With imminent attack not anticipated, no special precautions were taken as the Allied force was thought generally superior as it comprised six heavy cruisers, two light cruisers and four destroyers, a mixed American and Australian force under the command of an Australian officer, Rear Admiral Crutchley. This force could not be concentrated, however, because of the geography of the approaches to the landing area. Between Guadalcanal and the islands of Florida and Tulagi to the north there is a deep channel between 15 and 25 miles (24 and 40 km) wide. At the wider end, to the north-west, which Mikawa was now approaching, the sound is divided by Savo Island, about 5 miles (8 km) wide. Between Guadalcanal and Savo, Crutchley had established a southern force comprising his Australian flagship Australia, her sister ship Canberra and the US Chicago, and between Savo and Florida/Tulagi was a complementary northern force of the US heavy cruisers Astoria, Quincy and Vincennes. Across the approaches to the north-west, and serving as pickets to warn of the Japanese approach, were two radar-equipped American destroyers. The south-eastern approach to the area, which was thought a less likely avenue of Japanese advance, was allocated to two light cruisers and two destroyers.

In overall terms, Crutchley’s disposition of his force was tactically sound, at least in theory. The evening of 8 August was very dark, with low cloud and periods of heavy rain. Turner was distinctly worried by the withdrawal of Fletcher’s carriers, and summoned Crutchley to a meeting. Crutchley covered the 20 miles (32 km) to the area off Lunga Point on Guadalcanal’s northern shore in the Australia, leaving the southern force to his deputy in the Chicago. Crutchley arrived off Guadalcanal at 22.30 hours, and at this time the Japanese force was only some 50 miles (80 km) distant but closing rapidly and undetected. At 00.43 hours on 9 August the Japanese, in line ahead with the Chokai in the van, sighted an American destroyer at the distance of more than 5 miles (8 km) despite the darkness. This was Blue, which was covering the approach to the southern channel past Savo Island as another US destroyer, Ralph Talbot, was covering the northern approach.

Despite its extended length and approach from the expected direction, the Japanese force was not detected visually or by radar, and passed between the two ships at about 26 kt. Anxious to deliver his attack and withdraw before any air strike from Fletcher’s carriers, which he believed still to be present, Mikawa risked the loss of surprise by launching reconnaissance aircraft. These were seen by the Americans but the significance was not appreciated. By 01.25 hours the Japanese had Savo Island abeam, and soon after this sighted the two remaining cruisers of the southern group. At 01.38 hours the Japanese ships opened their attack with the typical ploy of a salvo of torpedoes and, only minutes later, the peace of the night was shattered by the impact of two torpedoes on Canberra just as air-dropped flares bloomed overhead. Chicago was equally surprised and, even as the alarm was sounded, a torpedo shattered the ship’s bow. The battle was only four minutes old, and the Japanese ships had still not been seen. The two crippled cruisers nonetheless attempted to reply as the Japanese forces swept by them and started a turn to port round the south-eastern side of Savo Island. This disrupted the Japanese line to the extent that the Japanese now advanced in two parallel columns which, by a chance favourable to the Japanese, nicely enclosed the northern group of cruisers. Chicago had not alerted them, and they had not responded to the sounds of the first engagement only 5 miles (8 km) away. The three US cruisers, steaming in line ahead at a mere 10 kt with their guns unmanned and trained fore-and-aft, now found themselves lit up at close range by searchlights. At a range of barely 400 yards (365 m), the Japanese opened fire with every weapon at their disposal. The engagement lasted a mere 10 minutes, and ended with the three US cruisers on fire, mainly as a result of the fuel for their floatplanes leaking from shattered tanks and catching fire. Nothing stood between Mikawa and his primary target, the transport ships of the American assault forces. Yet at 02.00 hours Mikawa ordered a retirement, in the course of which the two radar pickets were fired upon. Allied losses were four heavy cruisers sunk and one, Chicago, severely damaged together with more than 1,000 men killed, while the Japanese had lost only 38 men killed when limited damage was inflicted on Chokai and Aoba.

By the time the ‘Northampton’ class was under construction, the other signatories of the Washington Naval Treaty had produced their second generation of heavy cruisers, and the Americans were yet again able to profit from a survey of these vessels: the primary lesson learned from this survey was that the French and Italians had decided that their first-generation heavy cruisers had sacrificed too much protection in an effort to secure the highest possible speed, and the new ‘Suffren’ and ‘Zara’ classes, together with the ‘Canarias’ class designed for Spain in the UK, were notable for improved protection at a modest sacrifice in speed. The British and Japanese did not follow the same course as they had already opted for a better balance of protection and speed, and the Americans felt that this was the best option for the ‘Indianapolis’ class of two ships, which were very similar to the preceding ‘Northampton’ class except for a redistribution of the armour to provide additional protection amidships. The details of the ships, which were launched in 1931 and 1932, therefore included a full-load displacement of 12,575 tons, an armament of nine 8-in (203-mm) guns and eight 5-in (127-mm) dual-purpose guns, protection in the form of a 4-in (102-mm) belt and 2-in (51-mm) deck, and a speed of 32.75 kt on the 107,000 hp (79780 kW) delivered to four shafts by steam turbines.

The final American heavy cruisers built to the constraints of the Washington Naval Treaty were the seven ships of the ‘Astoria’ class, which were in every way superlative ships matched in overall combat capability only by the single ship of the French ‘Algérie’ class and the three ships of the German ‘Admiral Hipper’ class. The principal changes from the ‘Indianapolis’ class were the rearward lengthening of the forecastle for improved seaworthiness, pole rather than tripod masts, and improved protection in the form of a longer belt and thicker armour for the decks, turrets and conning tower. The details of the ships, which were launched between 1933 and 1936, therefore included a full-load displacement of 13,500 tons, an armament of nine 8-in (203-mm) guns, eight 5-in (127-mm) dual-purpose guns and 16 1.1-in anti-aircraft guns, protection in the form of a 5-in (127-mm) belt and 3-in (76-mm) deck, and a speed of 32.75 kt on the 107,000 hp (79780 kW) delivered to four shafts by steam turbines.

The one unit of the ‘Wichita’ class, launched in 1937, had been planned as the eighth ‘Astoria’ class ship but in the event was completed to a standard resembling that of the ‘Brooklyn’ class of light cruiser except in its armament details. The ship had a full-load displacement of 13,700 tons, an armament of nine 8-in (203-mm) guns and eight 5-in (127-mm) dual-purpose guns, protection in the form of a 5-in (127-mm) belt and 3-in (76-mm) deck, and a speed of 32.5 kt on the 100,000 hp (74560 kW) delivered to four shafts by steam turbines.

This similarity between the ‘Wichita’ and ‘Brooklyn’ classes provides clear evidence of the gradual merging of American heavy and light cruiser design concepts, the heavy cruiser generally having slightly greater length and the light cruiser having five turrets each carrying three 6-in (152-mm) guns rather than the heavy cruiser’s standard arrangement of three turrets each carrying three 8-in (203-mm) guns. The Japanese also followed this concept, although not to so standardised a degree, and were therefore able to upgrade the ‘Mogami’ class light cruisers to heavy cruiser standard by the replacement of the triple 6.1-in (155-mm) turrets by twin 8-in (203-mm) turrets.

USS BaltimoreThe tendency towards the use of a conceptually similar design for light and heavy cruisers became fully evident with the ‘Baltimore’ class of 17 ships launched between 1942 and 1945 (only 14 being completed before the end of World War II) with an eighteenth following in 1951. The design was derived from that of the ‘Cleveland’ class of light cruisers with the hull lengthened by 65 ft (19.6 m) and widened by 4 ft (1.2 m), and with the main armament revised to heavy cruiser standard. By the time of the earlier ships’ completions, all but the German navy had in effect abandoned the heavy cruiser concept, but the US Navy still believed that with large oceans off its eastern and western seaboards there was still a need for heavy cruisers offering a combination of firepower, protection, speed and range that was unrivalled by anything but a capital ship. The ‘Baltimore’ class heavy cruisers were superb examples of this concept, which certainly retained a full validity up to and indeed after the end of World War II. The primary features of the ‘Baltimore’ class design were a considerable deck area to allow the siting of large numbers of short-range anti-aircraft weapons in addition to the turrets carrying the primary and secondary armaments, a shorter but thicker length of belt armour to provide enhanced protection for the ship’s ‘citadel’ region, and the absence of all side scuttles so that all interior spaces had to be artificially ventilated and illuminated. The details of these fine warships included a full-load displacement of 17,070 tons, an armament of nine 8-in (203-mm) guns in three triple turrets, 12 5-in (127-mm) dual-purpose guns in six twin turrets, 48 40-mm anti-aircraft guns in 11 quadruple and two twin mountings, and up to 28 20-mm anti-aircraft cannon in single mountings, protection in the form of a 6-in (152-mm) belt and 3-in (76-mm) deck, and a speed of 33 kt on the 120,000 hp (89470 kW) delivered to four shafts by steam turbines.

To complete the story of American heavy cruisers with 8-in (203-mm) guns, it is necessary to mention two classes that were designed during World War II but completed after the end of hostilities and then only in small numbers and in different forms. The ‘Oregon City’ class was planned as eight ships, but only four of these were completed to an improved ‘Baltimore’ class standard with a single rather than twin funnels to give the guns improved arcs of fire. The ‘Des Moines’ class was planned as 12 ships, but only three of these were completed to an improved ‘Oregon City’ class standard with automatic 8-in (203-mm) guns, a tertiary battery of 24 3-in (76-mm) anti-aircraft guns in 12 twin turrets to replace the 40-mm guns of the preceding classes, and a longer and thicker belt of waterline armour.

So far as any account of American heavy cruiser thinking is concerned, mention must also be made of the magnificently elegant ‘Alaska’ class of large heavy cruisers, often but wrongly called battle-cruisers. The origins of the class are to be found in the report before the USA’s involvement in World War II that Japan was following the German lead and building a class of ‘pocket battleships’. The US Navy responded with the ‘Alaska’ class projected at six large heavy cruisers of which only three were laid down and two actually completed to what was basically an enlarged version of the ‘Baltimore’ class design with a primary armament of nine 12-in (305-mm) rather than 8-in (203-mm) guns in three triple turrets and the protection scaled up to approximately the same extent. With a full-load displacement of 34,250 tons and a length of 808 ft 6 in (246.4 m), the large heavy cruisers of the ‘Alaska’ class carried a primary armament of nine 12-in (305-mm) guns in three triple turrets including a super-firing pair forward, a secondary armament of 12 5-in (127-mm) dual-purpose guns in six twin turrets, and a tertiary armament of 56 40-mm guns in 14 quadruple mountings and 34 20-mm anti-aircraft cannon in single mountings. The ships were protected by extensive but only moderately thick armour that included an 8-in (203-mm) belt and 3.75-in (95-mm) deck, and the highly impressive sustained speed of 33 kt was attained on the 150,000 hp (111840 kW) delivered to four shafts by steam turbines.