UNITED STATES NAVY (UNITED STATES OF AMERICA)

Ship project history: Designing of the ships of Iowa class has been begun in 1938. At definition of their data elements the General Board has returned to idea of a battleship for support of fast carrier forces and their protection against Japanese heavy and battlecruisers (North Carolina class battleships originally were projected for the decision of these tasks and should have 30kts speed). By the moment of beginning of design works limitations of London Naval conference of 1936, owing to abandoning of Japan to sign the total document, have been lifted from 35000 to 45000t of standard displacement, and allowed artillery calibre has raised from 356 to 406mms. It allowed to create the ship with protection and armament not yielding accepted on South Dakota class, having used a gain of displacement on more powerful machinery. In Iowa design the hull have lengthened almost on 70m at invariable breadth (the limited breadth of Panama canal). Increased L/B ratio together with on 60% more powerful machinery should ensure 33kts speed. The increased length of protected citadel has led to growth of armour weight though thickness of its elements, in comparison with South Dakota class, practically have not changed. Unique serious difference became increased to 368mm transverse bulkheads thickness, since the third ship of a class.

Iowa class ships received new 406mm guns with 50cal bore length. Occurrence of this artillery system is curiously enough: at protection and armament, similar of South Dakota, 10000t displacement growth has gone only on speed increase to 6kts, that could serve as a subject for critic of new project. At the same time the big number of ready 406/50mm guns (manufactured in the early twenties for battleships and battlecruisers become by a victim of the Washington conference) was ready or nearly so in Naval arsenals. Usage of these guns in new project allowed both to spare the finance, and to justify growth of displacement by transition to new artillery system. But it has appeared, that fitting of 406/50mm guns conducts to additional growth of displacement (still approximately on 2000t). The exit has been found in manufacturing of new guns, the blessing there was a reserve on designing. As well as on predecessors, heavy AA armament have been presented by 10 127mm guns in twin mountings which were supplemented by 4 x 4 28mm Mk 1 guns and 12 12.7mm MGs.

The project have approved in June, 1938, next year the order for building of ВВ61 and ВВ62 within the limits of FY1940 has been given out. In July, 1939 the decision about building of ВВ63 and ВВ64 (FY1940) has followed, and in September, 1939 have approved building of ВВ65 and ВВ66.

The building of battleships was conducted very qickly, and in 1943 the first pair has become operational. ВВ61 should become flagship and differed by a conning tower of the increased sizes. Ligh AA armament was changed in course of building: instead of 28mm and 12.7mm MGs ships received 40mm Boforses and 20mm Oerlikons.

The second pair has become operational in 1944, and here completion ВВ65 and ВВ66 was at first suspended, and then has been cancelled.

Ship protection: 141.4m inner belt, inclined at 19° to vertical, had 3.2m height and was 307mm thick (on 51mm cement layer and 22mm plating). This belt was covered by vertical 38mm outer belt. 19°inclined 8.5m in height lower belt was connected with main belt and tapered from 307mm at upper edge to 41mm at lower edge. Belt was connected with end barbettes by bulkheads. Thickness of fore bulkhead was 287 (Iowa, New Jersey) or 368 (Missouri, Wisconsin)mm, but at lower part of bulkhead it decreased to 216 (Iowa, New Jersey) or 297 (Missouri, Wisconsin)mm. Aft bulkhead has 287 (Iowa, New Jersey) or 368mm (Missouri, Wisconsin) thickness only to one level under main deck, its lower part was only 16mm thick but it was connected with steering gear belt. Steering gear compartment had 343mm 19°inclined belt and 287mm bulkhead expanded up to lower (splinter) deck. Flat main armour deck was connected with upper edge of belt and was 178 (near sides)-152mm (near center line) over citadel. One level higher there was 38mm upper deck. One level lower was flat 16mm (25mm over magazines) splinter deck. This deck extended aft from No3 barbette and was 157-142mm over steering gear belt. Main gun turrets had 432mm (on 63mm plating) faces, 241mm (on 19mm plating) sides, 300mm rears and 184mm crowns. Barbettes over main deck were 294mm at center line and 440mm at sides, but thickness decreased to 76-38mm under main deck. CT had 440mm sides and 184mm roof. 5.45m deep underwater protection consisted from 4 compartments and could resist exploding of 317kg TNT. Inner main and lower belts were used as 3rd longitudinal bulkhead.

Modernizations: 7/1943, Iowa: - 8 x 1 - 20/70; + 4 x 4 - 40/56 Bofors

3/1945, Iowa: - 2 x Mk 8, 4 x Mk 4 radars; + 8 x 2 - 20/70 Oerlikon, SR, SU, 2 x Mk 13, 4 x Mk 12/22 radars

5/1945, Missouri: + 8 x 2 - 20/70 Oerlikon

5/1945, Wisconsin: - 2 x Mk 8 radars; + 6 x 2 - 20/70 Oerlikon, SR, 2 x Mk 13 radars

6/1945, New Jersey: - SK, 2 x Mk 8, 4 x Mk 4 radars; + 8 x 2 - 20/70 Oerlikon, SK-2, SP, SU, 2 x Mk 13, 4 x Mk 12/22 radars

1948, Missouri; 1950, New Jersey; 1951, Wisconsin: - 2 catapults, 3 seaplanes, 6 x 4 - 40/56, 8 x 2 - 20/70, 49 x 1 - 20/70; + 3 helicopters, SPS-6 radar

1951, Iowa: - 2 catapults, 3 seaplanes, 5 x 4 - 40/56, 8 x 2 - 20/70, 52 x 1 - 20/70; + 3 helicopters, SPS-6 radar

1967, New Jersey: - 14 x 4 - 40/56, SPS-6 radar; + SPS-10, SPS-12 radars, ULQ-6 ECM suite, Chaffroc decoy launchers

1982, New Jersey; 1983, Iowa; 1986, Missouri; 1988, Wisconsin were modernized as follows:

Ship protection after modernization: 141.4m inner belt, inclined at 19° to vertical, had 3.2m height and was 307mm thick (on 51mm cement layer and 22mm plating). This belt was covered by vertical 38mm outer belt. 19°inclined 8.5m in height lower belt was connected with main belt and tapered from 307mm at upper edge to 41mm at lower edge. Belt was connected with end barbettes by bulkheads. Thickness of fore bulkhead was 287 (Iowa, New Jersey) or 368 (Missouri, Wisconsin)mm, but at lower part of bulkhead it decreased to 216 (Iowa, New Jersey) or 297 (Missouri, Wisconsin)mm. Aft bulkhead has 287 (Iowa, New Jersey) or 368mm (Missouri, Wisconsin) thickness only to one level under main deck, its lower part was only 16mm thick but it was connected with steering gear belt. Steering gear compartment had 343mm 19°inclined belt and 287mm bulkhead expanded up to lower (splinter) deck. Flat main armour deck was connected with upper edge of belt and was 178 (near sides)-152mm (near center line) over citadel. One level upper there was 38mm upper deck. One level lower was flat 16mm (25mm over magazines) splinter deck. This deck extended aft from No3 barbette and was 157-142mm over steering gear belt. Main gun turrets had 432mm (on 63mm plating) faces, 241mm (on 19mm plating) sides, 300mm rears and 184mm crowns. Barbettes over main deck were 294mm at center line and 440mm at sides, but thickness decreased to 76-38mm under main deck. CT had 440mm sides and 184mm roof. 5.45m deep underwater protection consisted from 4 compartments and could resist exploding of 317kg TNT. Inner main and lower belts were used as 3rd longitudinal bulkhead.