Convergence of unbuilt battleships

Warship design and construction, terminology, navigation, hydrodynamics, stability, armor schemes, damage control, etc.
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Convergence of unbuilt battleships

Post by Mostlyharmless » Wed Jun 20, 2018 5:09 pm

The H39 Battleships would have had a main armoured deck, MAD, of 120 mm over the magazines under an 80 mm armoured weather deck. They would have had a 100 mm MAD over the machinery under a 50 mm weather deck. Thus they are a natural evolution from Bismarck, following a similar philosophy. On the other side of the Atlantic, the Montana Class as designed in 1941, had a 60 lb on 30 lb bomb deck above a 5.8" on 50 lb main deck.

However, the H41 design according to Wikipedia (referenced to Gröner, Erich (1990) German Warships: 1815–1945, page 37), the MAD was increased to 200 mm following the penetration of Scharnhorst's decks by five British bombs in July 1941 at La Pallice.

Meanwhile, according to Friedman U.S. Battleships, page 342, there was a 1942 proposal to increase the total bomb deck plus main deck from 9.24" to 10.4" to protect against a US converted 14" shell from 19,000 ft. which was believed to require a single 8.3" plate whilst the Montana design with its two laminates was believed to be equivalent to 7.3". Thus the proposed Montana might have had at least 8" under 2.25".

Of course, the H Class would have carried fewer guns but been able to fight at closer range than Montana.