OT: Questions about naval warfare in WW2

[RN7]

I have never been able to get a definite answer for the following questions so I thought I'd throw them out to the resident naval experts on the board.

1) At what point during WW2 did the US Navy overtake the Royal Navy as the worlds largest?

Although some might argue that the US Navy and even the Japanese Navy were the most powerful navies in 1939, from any figure I have ever seen the Royal Navy was numerically the largest navy in the world in 1939. It was not that much bigger than the US Navy in heavy units, but it was certainly the largest including cruisers, escorts and submarines. I would say the Royal Navy remained the more powerful in the Atlantic until 1945, but worldwide I would say the US Navy overtook it in late 1942 early 1943, am I wrong?

2) At what point during WW2 did the US Navy overtake the Japanese Navy in the Pacific?

The US Navy was always larger than the Japanese Navy but was it was split between the Atlantic and Pacific oceans. The Japanese Navy was all in the Pacific. Would early 1943 be right?

3) If Germany had completed the Z Plan (the realistic part of it) battleships, cruisers, aircraft carriers and escorts, and the Royal Navy had built the Lion Class battleships and other units to counter it, would the Germans have ever been able to dominate the Royal Navy in the Atlantic?

[Olefin]

2) At what point during WW2 did the US Navy overtake the Japanese Navy in the Pacific?

The US Navy was always larger than the Japanese Navy but was it was split between the Atlantic and Pacific oceans. The Japanese Navy was all in the Pacific. Would early 1943 be right?

Actually the US Navy in some ways was deficient to the IJN at the start of the war - the IJN actually had more carriers in commission - 6 fleet carriers and 4 light fleet carriers versus the US with 7 fleet carriers and 1 escort carrier - and they actually added several light and escort carriers early in the war and they basically were at parity with the USN in numbers of cruisers (but Japanese light cruisers were inferior to US ones in terms of guns and size)

Keep in mind that Japan and the Allies were actually very even at the start of the war as far as in terms of deployed ships in the Pacific but that Japan's initial victories gave them superiority in the Pacific which lasted until basically the end of the Guadalcanal battles - 1943 was where the US managed to rebuild their fleet, especially in carriers, to be able to take back the advantage in the Pacific by late 1943

The early battles gave them a big advantage sinking or disabling 9 battleships, one battlecruiser and basically destroying just about everything the Allies had in the Western Pacific. If they hadnt lost all four carriers at Midway it might have been mid 1943 before they lost naval superiority over the Allies.

As for the British Navy and when the US surpassed it - once the US really got going on building ships in 1943, along with the losses they had taken earlier in cruisers and destroyers, they were eclipsed by the USN. It was one reason that they conceded the Indian Ocean for so long to the Japanese - i.e. they literally didnt have the ships to risk there - not until after the Italians and Germans were out of the game.

Looking at Hitler's navy I dont think plan Z would have been the war winner - they certainly could have hurt the British more with the new ships - the real way they could have won was if Hitler had actually built a lot more submarines earlier and had been able to give the Kriegsmarine and effective naval arm. One of Goering's big mistakes - and he made a bunch - was not supporting the naval effort. Given more fighters to defend the subs and especially more patrol bombers and long range naval seaplanes even the force they had could have done a lot more damage to the RN. Add in the submarine numbers they had by early 1943 at the war start and the RN would have most likely lost.

[Olefin]

FYI this brings back memories of the discussions on ShatteredWorld on the fleets there - especially since there many of the proposed ships of WWII were actually built and used in combat - miss the days of my Scipione Africano stories about the Italian Navy in the IO and off East Africa in the alternate timeline of that site

[Adm.Lee]

Sometime around the middle of 1943 is when I'd say the USN bypassed both other navies, that's when the bigger ships from the 1940 Two-Ocean Navy were commissioned.

I can't recall the details of Plan Z, but if the Germans had the time to build more warships (presumably not when locked in a death struggle with the rest of the world), then the British would have had the time to wake up and build comparable numbers of ships.

[Olefin]

Originally Posted by Adm.Lee

Sometime around the middle of 1943 is when I'd say the USN bypassed both other navies, that's when the bigger ships from the 1940 Two-Ocean Navy were commissioned.

I can't recall the details of Plan Z, but if the Germans had the time to build more warships (presumably not when locked in a death struggle with the rest of the world), then the British would have had the time to wake up and build comparable numbers of ships.

That was one thing that was assumed in ShatteredWorld - i.e. that the German build up didnt happen in a vacuum - the Allies saw the size of their new BB's and their fleet and built up accordingly - of course there the Japanese also started with a much bigger fleet as well including the Design A-150 battleship - i.e the Super Yamato

[RN7]

Its hard trying to find accurate comparisons for fleet sizes during WW2. Data for the British and other European navies generally start in 1939, but the American and Japanese navies start from the end of 1941. So we have a gap of two years or more were the British are building/losing a lot of ships before America and Japan join the war.

Originally Posted by Olefin

2) Actually the US Navy in some ways was deficient to the IJN at the start of the war - the IJN actually had more carriers in commission - 6 fleet carriers and 4 light fleet carriers versus the US with 7 fleet carriers and 1 escort carrier - and they actually added several light and escort carriers early in the war and they basically were at parity with the USN in numbers of cruisers (but Japanese light cruisers were inferior to US ones in terms of guns and size).

The Japanese had more carriers than the US and Britain in 1941.

At the time of Pearl Harbour estimated US, British and Japanese naval strengths in the Atlantic and Pacific were...

Atlantic Ocean
Britain
12x Battleships (including 1 Battlecruiser)
8x Aircraft Carriers (including 2 Escort Carriers)
12x Heavy Cruisers
28x Light Cruisers
235x Destroyers (including Escorts)
80x Submarines

US
6x Battleships (excluding North Carolina and Washington on trials)
4x Aircraft Carriers (excluding Hornet on trials)
5x Heavy Cruisers
8x Light Cruisers
92x Destroyers (including Escorts)
58x Submarines

Pacific Ocean
Britain
4x Battleships (including 1 Battlecruiser)
1x Aircraft Carrier
4x Heavy Cruiser
10x Light Cruiser
13x Destroyers (including Escorts)
Unknown Submarines

US
9x Battleships
3x Aircraft Carriers)
13x Heavy Cruisers
11x Light Cruisers
80x Destroyers
53x Submarines

Japan
10x Battleships
9x Aircraft Carriers
18x Heavy Cruisers
17x Light Cruisers
103x Destroyers
74x Submarines

Plus Dutch (3x Light Cruisers, 7x Destroyers and 15 Submarines)


On a side note excluding the 2 Japanese Yamato Class battleship the broadside weight of a full salvo from American battleship guns from 1939-45 was superior to all other battleships during WW2 including the big British Nelson Class battleships. That's why the Japanese went for them at Pearl Harbour. If the British had built the Lion Class with upgraded 16inch guns they might have closed the gap with the American battleships.

I'm still on the fence with the German Z-Plan. Some good designs but also some unrealistic ones, and the Germans had no aircraft carrier experience.