Rn vs IJN

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See the Tabulated Record of Movements over on the Combined Fleet site
 
HMS Warspite says: "Hold my beer".
 
Carrier War
Japanese fighters (A6M) are significantly more effective than the British carrier fighters (Fulmars, Rocs, Sea Hurricanes) and significantly out-range them.

The same can be said about the F4F-3/4 yet they fought the A6M to a draw, despite a crushing defeat now and again. The Roc is unlikely to be a carrier borne fighter in 1942.

Japanese have seaplane fighters (A6M2-N) which are also (probably) superior to British carrier fighters

Seaplane fighters were a very minor factor in the PTO.

Japanese carrier strike aircraft are also vastly superior (D3A and B5N vs Skua and Swordfish) And better (?) air-launched torpedoes (?)
The D3A and Skua (and a bomb armed Fulmar) are about equal in overall capability and not much different than the SBD which proved to be the scourge of the KB in 1942. There's really no difference in IJN and FAA air launched torpedoes in 1941/42. The Albacore would be the frontline torpedo-divebomber in FAA carrier service with the Barracuda coming along in mid/late 1942. The evidence suggests that by May 1941 the RN Mk XII had a 440lb warhead:
"A Note on Sources: Although this weight of 388 lbs. (176 kg) appears in almost all references for the 18" (45 cm) Mark XII torpedo, a memo from DNC Stanley Goodall dated 13 February 1942 states that the warhead weight was 440 lbs. (200 kg)." (Navweaps)

"Enclosure 4

An extract from D.N.C's dealing specifically with para. 8 of First Sea Lord's minute of 1st February (Enclosure 2.)

... British aircraft torpedoes that struck "BISMARCK" contained an explosive charge of 440lbs., whilse those fired by Destroyers contained an explosive charge of 750lbs..."




Japanese aircraft carriers carry more aircraft (60-70 vs 40-50)
The KB carried an average of 55 aircraft/carrier in the IO in April 1942 and ~57 (operational) at Midway. They did carry an overload number of aircraft at PH but this wasn't repeated. After Midway, the Zuikakus began to increase their complement from ~62 at Coral Sea to 72 at Eastern Solomons. IJN aircraft/aircrew production/training was insufficient in 1942 and couldn't replace losses.

Japanese land based strike aircraft have long range and can sink enemy ships in daylight
The same was true for Coastal Command and RAF/FAA maritime strike aircraft. *(see below)

British have radar and some aircraft that can fly strikes at night with radar (Swordfish) albeit at very short range
The IJN had considerable difficulty in locating enemy carrier formations even in daylight. Radar equipped Albacores and Swordfish could carry DTs and internal aux tanks, so night range was similar to daylight range, however ASVII conferred advantages even in daylight as it could see through cloud. Night range and daylight range was constrained by recon and navigation capabilities and the IJN's recon wasn't outstanding in 1942.

British have Wellingtons which can also drop torpedoes at night and have very long range
* Yes and other aircraft and they can be used in daylight!


Surface Sea War
Japanese have the largest and most powerful battleshps in the world (Yamato and Musashi)
Yamato was available in Mid 1942 by which time all five KGVs would be in service (with no ETO war). Musashi not till early 1943 by which time 2 Lion class battleships (9x16in guns/30 knots) would be in service.
Japanese have (arguably) more modern battleships and battle cruisers, and better cruisers
Hood would be reconstructed with no ETO war.
6 Dec 1941 the IJN has 6 battleships and 4 battlecruisers. The RN would have 3 new KGVs, 2 Nelsons, 3 rebuilt QE class and 7 older battleships with Renown (rebuilt) and Repulse with rebuilt Hood nearing completion. Advantage seems to be with the RN.
Japanese light cruisers are very effective torpedo platforms
With two notable exceptions (Oi and Kitikami) this is untrue. The RN C, D and E class have more torpedo tubes/ship than their IJN counterparts. All the modern light cruisers from the Leander class forward carry TTs. The older IJN light cruisers generally carry 21in torpedoes,
Japanese have seaplane tenders and seaplane cruisers
No real world advantage over RN cruisers if they are used as per their full aircraft capacity. The BCE has the aptly named HMAS Albatross...

Japanese ship-launched torpedoes with twice the range of the British and much greater speed
Yes, this is an advantage, but the RN torpedoes actually work and they were vastly superior to USN torpedoes. In the close range surface engagements around Guadalcanal RN torpedoes, (and flashless propellant) would have been devastating to the IJN.
Japanese have superior night training and optics
Debatable about night training.

British have less-flash powder (unlike the Americans)
The RN has flashless powder - I've proven that. The USN didn't have a reduced flash propellant until early 1943.


Submarine War
Japanese probably better sub-launched torpedoes (I actually haven't checked this)
If we replaced USN torpedoes with RN torpedoes in Dec 1941 then the war in the PTO would probably have ended a year sooner as the IJ MM would have been destroyed that much sooner.



Land War
Japanese tanks have HE capability
No advantage as IJA tanks were pretty useless anyways.

Japanese Army is unusually fanatical and creative
Japanese resoundingly beat the British in land battles in 1942 (in the r
eal world)
The IJA was generally fighting ill equipped 2nd line UK and Empire units and they had the advantage of bases in FIC.
 
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My assumptions per the list above that you were having some trouble with was based on the idea of a war happening from late 1941 - mid 1943, per previous discussions, though I'm willing to be flexible. The kit I mentioned was mostly what looked like was available in late 1941 through 1942.

As far as the Roc, someone upthread suggested that they might still have them if they hadn't been tested against the Germans and found wanting. Skuas would probably at least still be available, they had better range than the Swordfish.

As for striking during the day, I just think Wellingtons and Swordfish are going to be dead meat if they run into Zeros or Ki-43s during daytime. Probably Ki-27 or A5M as well.

I also don't discount British torpedoes at all, as noted they were certainly better than the US type. But the Japanese types are not only twice the range but 25% faster. And they carry plenty of them.

Basically in this scenario, it looks to me like the British need to try to fight at night, but probably also need to avoid surface battles, at least until their radar (and associated procedures) become sophisticated and reliable enough to really give them an edge.
 
All of the ships took several months to go on first war cruise.
Other wise all 5 would be repeating the PoW first war cruise (against the Bismarck and we know how that went)

To clarify - when I mentioned KGV, I meant as a class. And I know the British had some other modern battleships, (just as the Japanese had more than just Yamato and Musashi) but I think the Japanese had a few more of the more modern heavy surface combat vessles (BBs, BCs, and CAs)
 
That's a far cry from one modern BB and a bunch of oldies.

I didn't actually say that

With radar, weather (in SEA a major factor) and to a lesser extent night battles are more promising from the Brit angle.

I disagree. The Japanese superiority in optics is pretty telling, though it would depend on specific conditions. The Brits best bet is probably during poor weather or a new moon. They would need to plan their attacks very carefully..


I don't know why you think the Brits would be able to attack three on one. I think that is highly unlikely. They had roughly parity in battleships, first of all. Second, the British would have to run a gauntlet of Japanese carrier and land based strike aircraft to even make it to the battle. Third, they would be facing type 93 torpedoes even before they got into gun range, in all probability.
 

I think that is a a stretch. The F4F-3/4 was inferior to the A6M, but nowhere near to the extent of the Fulmar which was 50-60 mph slower among other problems, and the A6M had as we well know, much greater range / flight endurance than the more evenly matched (at least in terms of speed) Sea Hurricane. And we also know that Hurricanes did very poorly against both A6Ms and Ki-43s, much worse than F4Fs did.

Japanese have seaplane fighters (A6M2-N) which are also (probably) superior to British carrier fighters

Seaplane fighters were a very minor factor in the PTO.

Seaplane fighters were maybe not quite as trivial as you seem to think, but they were at a substantial speed disadvantage vs. an F4F or say, a P-40. They could just about catch a SBD but not by a wide margin.

None of this would not be the case against most of the RN aircraft. A6M2-N was just as fast as a Fulmar, still had a maneuverability and climb advantage

A6M2-N was, needless to say, much faster than a Skua, let alone a Swordfish or Albacore. It was also a good bit faster than a Wellington.
Even the F1M was a much faster than a Swordfish or Albacore and could probably shoot them down pretty easily. They were fast enough to catch Wellingtons too.

I'd say the long range land-based Ki-45 heavy fighters would also be quite a major problem for British carrier aircraft and long range land based strike aircraft and bombers, though they might be able to alleviate that somewhat with the Beaufighter.


That is an absurd joke. The SBD was an extremely accurate dive bomber by the standards of WW2, and sunk more actual warships (in deployment, not just sitting in a harbor) than just about any other plane in the war. The D3A is in fact the only one which compares to it. The Skua doesn't even come close to either of them. The SBD could somewhat hold it's own against a Zero. The Swordfish did well but is a lot less impressive if you don't count Tarranto.

Lets compare

Stats----------------SBD--------TBF-----Swordfish----Albacore---Skua----Barracuda----D3A------B5N----D4Y----B6N
Top Speed(MPH)---250--------270--------143-----------161--------225--------240----------270-------235-----340-----300
Range---------------1100-------900--------552----------710--------760--------686-----------915------600------910-----1,085
Bomb Load---------2,250------2,000-------1670--------2000--------500-------1600----------810------1760----1800----1760
Max bomb----------1,000------Torp--------Torp---------Torp-------500--------Torp----------550------Torp----1100----Torp


I'll deal with the air launched torpedoes in another post. I already did some work on that one.

"Couldn't replace losses" depends on them taking a lot of losses, like sunk carriers. And it's not the same as carrying fewer aircraft.


I think opportune fowl weather was probably the only hope for the British in this scenario. Certainly their best bet, for a variety of reasons.

British have Wellingtons which can also drop torpedoes at night and have very long range
* Yes and other aircraft and they can be used in daylight!

So long as they are nowhere near any Japanese fighters.
 
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For myself the big difference is the aircraft. I don't believe for a second that the Hurricane had any real chance against the Zero. The Skua was a dive bomber that was probably as good as the Japanese but the Swordfish had no hope in air combat against the Japanese and the B5 was a good aircraft.

The one salvation was the British had much better radar and what I don't think has been mentioned AA weapons and directors. Japanese warships in December 41 were very poorly armed, and effectively had no Radar.

Yamato 12 x 5in DP, 24 x 25mm, 4 x HMG
Fleet Carriers were roughly similar.
8in cruisers normally had 8 x 5inDP and 8 x 25mm

All the above were considerably exceeded by any RN equivalent and had the FAA managed to break through or avoid the fighter cover the Japanese could have been in serious trouble.

In surface combat the British BB's excluding the R class were at least as good as the Japanese battleships with the obvious exception of the Yamato class. They were either new (KGV class) or well modernised (Nelson and QE) with very good fire control and well equipped with radar which in all but perfect calm conditions would give the RN a good advantage.

Battlecruisers - The Repulse, Renown and Hood all modernised would be capable of taking on the Japanese BC's which were all modernised WW1 battleships, without the radar and AA defences of the British ships.

Cruisers. The Heavy Cruisers were a good match and the British light cruisers were considerably better than the Japanese vessels.

A note about Radar. Even the Royal Sovereign by 1942, (Infuriatingly I don't quite know when) had the following, a Type 279 air warning radar, a Type 273 surface-search radar, a Type 284 gunnery radar and two Type 285 anti-aircraft gunnery radars were installed. Not bad, and with this, even the RS would have stood a good chance against the Japanese BB's.
 

I did mention the British air defense radar in my list. I think it would help in terms of attrition, but I don't think it could save Capital ships and Carriers from being sunk by IJN aircraft.
 
For myself the big difference is the aircraft. I don't believe for a second that the Hurricane had any real chance against the Zero. The Skua was a dive bomber that was probably as good as the Japanese

I don't necessarily disagree with your assessment of the ships, it's arguable but you make fair points. The Skua vs. the D3A though I think is a wash. Same with Skua vs SBD. It's not even close.
 
I think once the British have the longer range Spit VIII around they will be in much better shape. And I think Mosquito could help a lot but they didn't do so well in tropical climates (I think they had trouble with them de-laminating in India)
 
I didn't actually say that

You only mentioned the King George for modern BBs. Sorry I didn't read your mind that you meant all of them, but you not mentioning them at all is, at best, quirky, considering how detailed your rundown purported to be.

I disagree. The Japanese superiority in optics is pretty telling, though it would depend on specific conditions. The Brits best bet is probably during poor weather or a new moon. They would need to plan their attacks very carefully..

Optics are easily defeated by weather. They also are less efficient at night-time and long range, depending on moon.

I don't know why you think the Brits would be able to attack three on one. I think that is highly unlikely.

Because by the middle of 1942, when both Yamato are afloat, the Brits will have five, count 'em five, modern battleships. Put QEs and Rs against Nagatos, and Kongos *snort* and the others. Three moderns on Yamato, two on Musashi.

What's the issue with understanding this?

They had roughly parity in battleships, first of all.

lol, are you counting Kongos as battleships? Mistake there. 8" of armor ain't a BB. You got 4 WWI hulks against 7, three rebuilt WWI BBs against two, and 5 moderns against 2 Yamatos. The Kongos, as shown OTL, were fragile. One got shot the TF up by Laffey, to be hors d'aircraft the next day.

Second, the British would have to run a gauntlet of Japanese carrier and land based strike aircraft to even make it to the battle. Third, they would be facing type 93 torpedoes even before they got into gun range, in all probability.

Really? Like the Brits didn't sit upon the Straits of Macassar? Like their lines of communication through the IO and back to Suez Canal ran through Japanese waters? This is a silly "point". It's like you haven't looked at a map.

If the Japanese wish to interdict the Brits, they will have break through. to break into the IO. Supply lines for both sides are going to be hard to hit.

As for the torpedoes, sure, they're dangerous. But they're not infallible, they depend upon the crewmen shooting them, and the spotters targeting them. How many hit Washington or SoDak? How many hit their own transports? Yeah, they ain't silver bullets.

I think your bias is painting your vision. Slow down a little and actually think about this.
 
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I think the Japanese had a few more of the more modern heavy surface combat vessles (BBs, BCs, and CAs)
end of 1941 no European war
British...............................................Japanese
BBs...8 modern................................2?
BBs...7 old.........................................4
BCs...2 modern...............................4
BCs....1 old.......................................0
CAs....15..........................................18
CLs....15 Large modern................0
CLs ....18 Small modern...............0
CLs......24 small old......................17

Discounting the modern CLs is a bit disingenuous. Ask the Graf Spee


British modern BBs, 3 KGVs, 2 Rodney's, 3 QEs
British old BBs, 2 QEs and 5 Rs
British modern BC, modernized Hood, Renown
British old BC, Repulse.

Japanese Modern BB, 2 Nagatos.
Japanese old BBs, the four 14in gun ships, maybe they fall in-between?)
Japanese modern BCs, only in comparison to the Repulse.


Cruisers should be fairly clear from earlier postings.

Preliminary gun stats in early post. British 15in guns are very dangerous.

Difference from the US ships is that the worst British cruisers had 6 torpedo tubes. The Leander's (small modern) had 8 tubes.
No US CA had torpedoes (older ones were removed in pre-war refit) so only the old Omaha's and the New Atlanta's had them. A rather small percentage of the American cruiser fleet so it didn't really matter if they had them or not or good they were. Counted a lot for the US destroyers.

British 1941 AA was not good, Japanese 1941 AA sucked.

For a end of 1941 match up with a European war that was less intense than historic, deduct appropriate number of British ships.
 
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The Japanese had no other modern battleships aside from the Yamatos.
I am going to give him this one. The Nagato's weren't laid down until 1919-1920 so definitely post Jutland.
Just under 3,000 tons of armor added, New boilers slightly upgraded, modified turrets installed with increase elevation and ammo so that ranged increased by 7,500 yds, not that it mattered. The old range was longer than the record (?) held by the British 15in gun for longest ship to ship hit.
 
The limitations of navigation and recon seldom permitted carrier strikes longer than 250nm.

The effective range of the SBD-3 with a 500/1000lb bomb was about 250/280nm. Typical range figures quoted for USN (and sometimes IJN) aircraft are theoretical, no reserve ranges, at low altitude and are not real ranges. The SBD-3 never carried a bomb load larger than 1000lb from a carrier, and SBD-3s ranged forward had to have their bomb load progressively reduced to 500/2x100 and then to a single 500lb bomb, depending on weather conditions.
Max speed for a TBF-1/1C was 257/254 mph at 12K ft effective range was about 250nm which was similar to a Albacore with a torpedo and Aux tanks. The TBF-1 couldn't carry DTs and a torpedo when operating from a carrier. Albacore max speed with a torpedo was ~170mph; 161mph was with 6 x 250lb bombs.
The IJN used the D3A-1 until late 1942; max speed was 240mph with a typical 550lb bomb load as the D3A-1 appears to have only carried a single bomb at Coral Sea and Midway. The Skua could carry a 500lb bomb and additional wing mounted bombs but typically carried a single 500lb bomb while the Roc could be used as a DB. D4Y and B6N were late 1943/44 aircraft. The KB was handicapped because no IJN carrier had a catapult.

The Fulmar II was cleared to carry a 500lb bomb in June 1942 but this was a latent capability that always existed in the Fulmar II. Proposals by Fairey to strengthen Fulmar flaps for use as dive brakes were scuttled by the FAA upon the outbreak of the ETO conflict due to the urgent need for a folding wing carrier fighter.
 
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