Battleship Modernisations OTL
This is a list of the major refits applied to the Queen Elisabeth and Repulse class:
1919-22 Repulse - £860,684
1923-26 Renown - £979,927
1924-26 Warspite
1926-27 Queen Elisabeth
1927-28 Barham
1927-29 Malaya
1929-30 Valiant
1930-33 Barham
1932-36 Repulse - £1,377,748 - Partial Modernisation
1934-36 Malaya - £976,963 - Partial Modernisation
1934-37 Warspite - £2,362,000 - Full Modernisation
1936-39 Renown - £3,088,088 - Full Modernisation
1937-39 Valiant - cost unknown but probably similar to Renown - Full Modernisation
1937-41 Queen Elisabeth - cost unknown but probably similar to Renown - Full Modernisation
The refits applied to the 5 Queen Elisabeth class 1924-33 cost about £1 million each. According to Brown in the above book Hood's planned refit had an estimated cost of £4½ million and the estimated time for the refit was 3 years.
Battleship Modernisations TTL
The signing of the First London Naval Treaty on 22nd April 1930 extended the Battleship Building Holiday from 12th November 1931 to 31st December 1936. In response the Admiralty lobbied the Cabinet to sanction SLEP refits (which included re-boilering) for the 8 best old battleships (5 Queen Elisabeth class, 2 Repulse class and Hood) that would extend their service lives from 20 to 30 years. Each refit would take about 3 years and cost £3 million except for the £4½ million it would cost to refit Hood. The total cost of the programme which was to be spread over 10 years was estimated to be £25½ (equivalent to the building cost of 3½ Nelson class battleships).
ITTL all 5 Queen Elisabeth class had refits along the lines of Queen Elisabeth herself and Valiant IOTL except that the existing 6" gun battery was replaced by twenty 4.7" in 10 twin turrets instead of the OTL 4.5" guns. Similarly Repulse and Renown were refitted to the same standard as Renown in 1939 ITTL except it had 4.7" guns instead of 4.5" guns. IOTL the proposed refit of Hood included replacing the existing 5.5" battery with sixteen 5.25" in 8 twin turrets. IOTL it was twenty 4.7" in 10 twin turrets like the other modernised ships.
ITTL the refit of Barham that began in 1930 became the prototype and because of the extra work involved it continued into 1934. Queen Elisabeth's OTL refit was brought forward to 1931 to make space for Hood. Therefore from 1930 the TTL list of refits was:
1930-34 Barham
1931-34 Queen Elisabeth
1932-36 Repulse
1934-37 Malaya
1934-37 Warspite
1936-39 Renown
1937-39 Valiant
1937-41 Hood
New Battleships
The British don't have the 1936 LNT reduce the gun calibre limit to 14". The design of the King George V Class was frozen a year earlier (i.e. when still armed with nine 15") and the turrets were ordered a year earlier. The earlier order for the turrets allowed all 5 ships to be completed 3½ years after they were laid down, which was the planned building time in OTL. That is:
01/01/37 to 01/07/40 for King George V - Actual completion 11/12/40 - 5 months late
01/01/37 to 01/07/40 for Prince of Wales - Actual completion 31/03/40 - 8 months late
05/05/37 to 05/11/40 for Duke of York - Actual completion 04/11/41 - 12 months late
01/06/37 to 01/12/40 for Howe - Actual completion 29/08/42 - 21 months late
20/07/37 to 20/01/41 for Anson - Actual completion 22/06/42 - 17 months late
The secondary armament is either sixteen 6" in eight twin turrets or twenty 4.7" in ten twin turrets. This would have been the secondary armament of the TTL Lion class and TTL Vanguard.
Except that the Super Implacable class aircraft carriers Invincible and Inflexible were laid down in the summer of 1939 in place of Lion and Temeraire. An additional Audacious class aircraft carrier was built in place of Vanguard.