Author Topic: WWII British/Australian Battlecruiser and Large Light Cruiser  (Read 2377 times)

Offline Volkodav

  • Counts rivits with his abacus...
  • Much older now...but procrastinating about it
WWII British/Australian Battlecruiser and Large Light Cruiser
« on: February 24, 2016, 12:24:45 AM »
Planned build:


- Nelson type battlecruiser with two quad 14" secondary TBD
- 16" KGV
- Australian built large cruiser - thinking a Renown hull with twin 14" from my two KGV kits plus either lots and lots of 5.25" twins (also from the KGVs), or a mix of 6" and 4.5" twins from nelson and renown kits.
- Maybe Australian large cruiser with four triple 8" supplied lend lease from the US.


- Post war completed County with Belfast superstructure, 4x Mk26 6" and 6x Mk6 3", plus maybe 2x Sextuple Bofors.
- Post war KGV BBG (will have left over 15" from Renown, maybe a notional RN standardisation on 15", as a secondary to the missiles, due to Vanguard and surviving Hoods)

Back story

During WWI Britain managed to build Renown, Repulse, Courageous, Glorious and Furious, as well as starting four Hood class battle cruisers (Friedman suggests the RN would have been better off completing all four as Hoods and keeping them post Washington), verses no Battleships.  Post war battlecruisers were considered indispensable and future large cruisers were planned to lead cruiser squadrons and possibly more balanced Dominion Fleet Units. 

These plans and most battlecruiser construction was killed off by the Washington Naval Limitation Treaty, leading to mass production of 8" gunned 10,000ton, heavy, or "Treaty", cruisers. These in turn were limited by the London treaties as Britain desired to cut cruisers to 8,000tons and 6" guns.  In the 30s and 40s the only battlecruisers were the French Dunkerques and the German Scharnhorsts, also often referred to as battleships, and the US Alaskas, which were termed large cruisers, what if the UK had a war emergency large cruiser or battlecruiser design?

My thinking is, based on WWI experience, the UK believed that once war broke out no new battleships would be laid down, but that battlecruisers or large cruisers (of the type considered for far east service in the early post Great War years) could be built.  Further more compromises brought about by treaty and financial restrictions, as well as the requirement for as many light cruisers for trade protection as possible, meant that there was no longer heavy cruisers being developed or built in the UK either.  This lead to both large cruiser and battlecruiser designs being prepared and kept up to date for emergency war programs to rapidly supplement the existing battleships and heavy cruisers and hopefully alleviate the rising possibility of concurrent European, Mediterranean and Far East threats.

The battlecruiser would be a fast Nelson with two quad 14" turrets, while the large cruiser, a scaled up London heavy cruiser hull with two twin 14" turrets ordered for KGV class battleships, that if completed would do so as escalated 2nd London Treaty battleships with three triple 16" turrets.  As originally designed both would have twin or triple 6" secondary batteries and multiple 4.5" UD DP mounts, with later evolutions switching to twin 5.25" DPs in place of both 6" and 4.5".  Both would have extensive aircraft facilities, the battlecruisers aft as on the French Dunkerque and Richelieu classes, while the large cruiser would have cross deck, midriff catapults with flanking hangers.

With the start of the war the battle cruisers were ordered from UK yards while the large cruisers were laid down at Cockatoo Island Dockyards in Australia.  The reason for this was capacity prevented all from being built in the UK, especially if the KGVs were to be completed with 16" guns and the fact that shipbuilding had been specifically developed in Australia as part of plans to defend against an inevitable Japanese attack that had been anticipated since before the end of WWI. (the UK had not been overly concerned when Japan refused to sell one or to Kongo Class to the RN post Jutland but their subsequent refusal to provide ships and crews, under Japanese control, to help defence the UK against German raids led to genuine concern that they may not be as firm an ally as hoped)

Pre WWI plans had foreseen the RAN growing to three fleet units (each with an armoured cruiser or battlecruiser, three trade protection cruisers, three submarines, six destroyers and a tender) for forward defence, plus additional armoured/battlecruisers, cruiser and submarine squadrons and destroyer flotillas for national defence and the young nations shipyards were grown to meet this requirement.  With the massive increase in size, manning and capability of all warship types during WWI these original plans became unaffordable and were replaced by more modest ones developed by Jellicoe on his tour or Dominion defences in 1920.  Even these were seen as unaffordable and were being recast with the planned new large cruisers instead of new battlecruisers (perhaps even seeing the transfer of Courageous and Glorious), prior to the Washington treaty killing off the option.

As a direct result of Washington it was decided that the RAN would standardise on 10,000ton treaty cruisers and progressively replace, not just the RANs sole battlecruiser with a pair of them, but to progressively replace all current protected and light cruisers with them as well.  With the ranges ships were required to cover in the RANs concept of operations it was also determined that destroyers should be replaced with small cruisers or destroyer leaders and that torpedo boats should be transported by larger mother ships.  For the cruisers it was decided to build a modified Kent locally by Vickers at Cockatoo Island Dockyards, this was more expensive than building them in the UK but cheaper than the alternative of building them overseas and having to give CODOC a succession of make work projects to keep it open.  The first two ships took longer to build than planned but were still ready in 1932 and 34 respectively, then a modified 6" gunned version, to satisfy the London treaty, in 36, 38 and 39.

Thus as WWII drew near Australia was still effectively building modified heavy cruisers in their entirety, hulls, machinery and armament, in facilities that had started to be expanded during WWI to build battle cruisers.  These facilities were able to rapidly switch from light cruisers back to heavy cruisers (of improved design), as well as starting work on new large cruisers.  The new larger cruisers were the second type with a uniform 5.25" secondary armament and were designed to either have a main armament of two twin 14" or four triple 8".
« Last Edit: December 25, 2016, 06:41:41 PM by Volkodav »