Rn vs IJN

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I'm not sure they will use the submarines "smarter".
USN could and did implement USW from practically 8/Dec/'41, but the last thing the UK wants is any current or future implementing that on them. (I recognize the KM was treading very thin line, but they weren't going all out at USW right out of the blocks)

Yeah I surmised as much

Same goes for RADAR and by extension homing beacons/radio communications/IFF: From posts here and on the navweaps site, it appears RN was so concerned with their enemy using SIGINT, that they didn't use the advantages that they had.

This is a very interesting point

While PoW did have legit issues with her RADAR operating in tropical conditions, it is looking more and more to me that it was also a conscientious decision to leave it turned off to prevent IJN forces from homing on it. If it isn't turned on, it isn't providing an advantage.

Very interesting. Always an issue with radar.

RN had Catalina fly over Bismarck to "relocate" her rather than provide Germany with inkling that their RDF was what gave Lütjens away. While if you're maintaining silence you're not giving your location away, you're also not providing your forces updates on your situation.

I didn't realize they tracked Bismarck via the radio direction finder

Without homing beacons allowing FAA aircraft to locate the carrier, a navigator is a critical to RN requirements.*
Up until the end of the Anglo-Japanese Alliance, IJN is partial to all the RN development in these area, so RN has legit concern.

So that is the reason why Fulmar and Firefly are required to have a second crewmember while nobody else's naval fighters do.

Without ETO/MTO experience, will FAA be operating Blackburn Rocs as its primary fighter? Will the follow on even be the Fulmar, but rather a next generation turret fighter - there were enough spec being floated for one. Does the Spitfire end after initial production as Hawker has Tornado/Typhoon as the RAF primary fighter.

Seems like the good characteristics of the Spitfire would be obvious even without combat, while the teething issues of the Tornado and Typhoon were well known. And certainly the first hint of combat anywhere around Europe, no matter how small, would reveal the merits of the Spitfire.

On other hand, Commonwealth forces fight such a different war that its hard to control all the butterflies.

Keep in mind, the Commonwealth did fight in the Pacific, not only the British but also in a big way, the Australians, and to a slightly lesser extent the New Zealanders. Even the Canadians even got involved a bit.
 
The more I think about the RN deploying Blackburn Rocs against the Japanese, the more I'd love to see that. Who knows? Maybe turret fighters are more viable against slower but more maneuverable, and more vulnerable Japanese aircraft. I doubt it, but I'd still like to see it. :)
 
RN had Catalina fly over Bismarck to "relocate" her rather than provide Germany with inkling that their RDF was what gave Lütjens away. While if you're maintaining silence you're not giving your location away, you're also not providing your forces updates on your situation.
Not sure about that.

There is a detailed account of the activities of the 3 Catalinas involved in post #3 here

This is the report that Ensign Smith submitted to the USN of his experience in finding the Bismarck

Note none of these aircraft were radar equipped.
Same goes for RADAR and by extension homing beacons/radio communications/IFF: From posts here and on the navweaps site, it appears RN was so concerned with their enemy using SIGINT, that they didn't use the advantages that they had.
While PoW did have legit issues with her RADAR operating in tropical conditions, it is looking more and more to me that it was also a conscientious decision to leave it turned off to prevent IJN forces from homing on it. If it isn't turned on, it isn't providing an advantage.

Without homing beacons allowing FAA aircraft to locate the carrier, a navigator is a critical to RN requirements.*
Up until the end of the Anglo-Japanese Alliance, IJN is partial to all the RN development in these area, so RN has legit concern.

It is worth while remembering that the RN attitude to radio emissions inter-war was born out of their experience in WW1. The RN established a series of Y stations around the world simply to glean intelligence from wireless traffic. As I noted in a previous post the FECB from 1936 obtained much information about the Japanese navy from radio transmissions. The USN also devoted much time to this work.

For the RN it was not simply not transmitting, but only transmitting when advantageous to do so, or not transmitting when there was no advantage to be gained. The use of radar in the Med in 1941 is a good example. The RN knew the Italians could detect Type 279/281 radar emissions at distances far greater than the RN could detect an attacker. That's radio signals for you. They just keep on going but getting weaker. Damned inconvenient really. In that period there was little night flying by the Italians. So the RN didn't use the radars at night so denying the enemy details of its movements until morning. But when there was an advantage in using it at night, as at Matapan, they didn't hesitate.

But there are other issues in relation to radio transmission from aircraft at this time. Firstly it was Morse Code based. HF voice radio came along in the early 1930s but was very short ranged (the RAF experience was c35 miles ground to air which they solved by repeater stations which was not possible for a fleet at sea, c5 miles air to air). VHF, which produced better range, was only introduced by the RAF in 1939/40 (8 squadrons by May 1940). The USN were even later. To make a Morse transmission at any distance a trailing aerial had to be wound out and in.

Think about the process for a moment. An aircraft needs to be sent out to detect an enemy. It spots it. A position has to be plotted and a signal created and coded. An aerial run out and the actual transmission made in dots and dashes. Wait for a response to ensure it has been picked up. Other signals will be made periodically until the limit of endurance is reached. And as for fighters, their role in the RN was not limited to patrolling around the fleet. They were intended to accompany the torpedo bombers and use MG fire and light bombs to attack escort ships (SEAD in today's terms). That is why in the 1930s there were single seater Hawker Nimrods and two seat Hawker Ospreys. Two aircraft for two different roles and the need for the second seat. From that came the dive bomber and the requirement for the Skua.

Then the Type 72 homing beacon equipment was not easy to use.

First hand account of radio use in aircraft at start of the war.

The USN YE homing system which entered service after the RN one proved much easier to use and in developed form was adopted by the RN in WW2.

It is interesting to note that while the Japanese were not so advanced in WW2 in developing radar, they did much more work in relation to detecting US radars and plotting their weak spots for exploitation in attacks.
 
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Then the Type 72 homing beacon equipment was not easy to use.

First hand account of radio use in aircraft at start of the war.

The USN YE homing system which entered service after the RN one proved much easier to use and in developed form was adopted by the RN in WW2.

It is interesting to note that while the Japanese were not so advanced in WW2 in developing radar, they did much more work in relation to detecting US radars and plotting their weak spots for exploitation in attacks.
Well it just goes to show you, every technology has it's flip side doesn't it? Radar isn't "just" an all-seeing eye, it also makes you shine in the dark. This was a big issue all through the Cold War when I was in the military and still is today, such as in Ukraine.

So of course the Japanese would try to exploit that side of it. It makes the whole thing trickier and ads another nuance to the story.

The whole aspect of the RDF is also fascinating to me. I know that US aircraft made wide use of these not just in the Pacific but also ... I think by around 1943, in China. You see planes, including single seat fighters with those little loop antennas on the back. Very helpful when trying to find your way home when low on fuel in the Himalayas. But I can definitely understand how for carriers it is a decidedly mixed blessing.

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Anyway I think those are RDF... or are they IFF? That's another pretty important and oft neglected issue especially for carriers...
 
I'm not sure they will use the submarines "smarter".
USN could and did implement USW from practically 8/Dec/'41, but the last thing the UK wants is any current or future implementing that on them. (I recognize the KM was treading very thin line, but they weren't going all out at USW right out of the blocks)

I'm confused, what does the USN have to do with this scenario?

As for RN using their subs smarter, I'm pretty sure they would, given that doctrinally the IJN saw their subs as part of the combat fleet, to be used whittling down the enemy forces prior to main combat.

Without homing beacons allowing FAA aircraft to locate the carrier, a navigator is a critical to RN requirements.*

It was my impression that the RN had homing beacons on some carriers by 1940, but I'm not well-read on the matter.
 
I'm confused, what does the USN have to do with this scenario?

As for RN using their subs smarter, I'm pretty sure they would, given that doctrinally the IJN saw their subs as part of the combat fleet, to be used whittling down the enemy forces prior to main combat.



It was my impression that the RN had homing beacons on some carriers by 1940, but I'm not well-read on the matter.

I think the point was they had it, but they were very aware of the downside of using it. And they were very good at exploiting the use of such technologies themselves (like tracking the Bismarck).

Ultimately I think RDF became pretty ubiquitous for naval aviation but I'm not sure of precise timelines.
 
See the link I posted. First fit of Type 72 was in Courageous in 1936, with Glorious, Furious & Ark Royal having Type 72 by outbreak of WW2. Eagle got hers in her Oct 41 - Jan 1942 but it had been planned for her Singapore refit that occurred just as war broke out. Hermes, it's not clear if she got it or not, although photos of her sinking appear to show it. Only Argus went without.

The Illustrious/Implacable classes all received a modified version allowing a mast to be carried above the Type 72.

Note Hermes had been in reserve or in use as a training ship since returning from the Far East in 1937. Shevwas hurriedly reactivated as a carrier in Aug 1939. Argus, after nearly a decade in reserve, from 1938 was a Queen Bee carrier until start of WW2. So no real need for Type 72.
 
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See the link I posted. First fit of Type 72 was in Courageous in 1936, with Glorious, Furious & Ark Royal having Type 72 by outbreak of WW2. Eagle got hers in her Oct 41 - Jan 1942 but it had been planned for her Singapore refit that occurred just as war broke out. Hermes, it's not clear if she got it or not, although photos of her sinking appear to show it. Only Argus went without.

The Illustrious/Implacable classes all received a modified version allowing a mast to be carried above the Type 72.

Note Hermes had been in reserve or in use as a training ship since returning from the Far East in 1937. She was hurriedly reactivated as a carrier in Aug 1939. Argus, after nearly a decade in reserve, from 1938 was a Queen Bee carrier until start of WW2. So no real need for Type 72.

Are you referring to direction finder system or radar?
 
RDF became pretty ubiquitous for naval aviation but I'm not sure of precise timelines.
RDF or radar first began to be fitted in British naval aircraft in spring 1941. 825 squadron in Victorious was lucky enough to have all its aircraft fitted with ASV II by the time of the Bismarck chase. Ark Royal's squadrons only had a few sets which went to flight leaders.

For undefined technical reasons it was not able to be fitted to Albacores until nearly the end of 1941. Even well into1942 it was not "pretty ubiquitous".
 
Ultimately I think RDF became pretty ubiquitous for naval aviation but I'm not sure of precise timelines.
from https://j-aircraft.com/research/gregspringer/radios/radio_systems.htm
The radio systems installed in the early A6M2 and A6M3 variants of the Zero were the Type 96 ku (aviation) Model 1 voice/telegraph system and the Type 1 ku Model 3 Radio Compass or Radio Direction Finder. The Type 1-3 was the standard RDF unit for most carrier-borne IJN aircraft. The Type 96-1 system was previously used in the A5M4 fighter series. The Type 96-1 system consisted of three components, all of which were installed in the cockpit. The transmitter and receiver were separate units that were placed low on the right side of the cockpit. They were hung in the standard shock mount that consisted of frames above and below the radio which had bungee cords secured to them. The bungees were looped around spools mounted on the radio casing. The suspended radio was protected from shocks by the flexibility of the cords.
The dynamotor module that powered the radios was mounted on a shelf in the left rear corner of the cockpit behind the pilot's elbow, as seen in the rough sketch. Dynamotors are generators that are driven by electric motors. They were a common means of powering aircraft radio equipment for several nations during World War Two as they avoided current fluctuations that occurred in the main electrical system of an aircraft. The type 96-1 operated in the frequency range of 3.8 to 5.8 megahertz. This is the lower end of the High Frequency or Short Wave band. Quartz crystal oscillators controlled frequencies. Power of the transmitter was 8 to 10 watts in voice mode and 30 watts in telegraph mode, called CW for 'continuous wave'. In 'At Dawn We Slept' Gordon Prange relates that one of the problems encountered in the IJN's preparation for Pearl Harbor was that they had never operated fighters farther than 90 miles from their carriers. 50 miles was the practical limit of utility of the voice radios under optimum conditions. Since the fighters would be venturing around 250 miles outbound on the mission it was necessary to initiate a training program in the use of the longer ranged telegraph code communication. It may be seen in the photo that Hirano's A6M2 did not have a code key installed and his transmitter is set to voice function. It seems that not all fighter pilots were trained in code transmission. Perhaps only unit leaders were supplied with the necessary equipment. The receiver circuit was a superheterodyne type. Total weight of the system was 38 pounds.

The control box for the Type 1-3 RDF was mounted above and between the two Type 96 sets. The control for rotating the RDF antenna was directly to the rear of the control box. The directional loop antenna was mounted in the fuselage deck beneath the canopy behind the rollover pylon. It consisted of two round stamped-metal frames with a center post. The actual antenna was made of insulated wire wrapped around and between the frames. Cloth was then applied over the wire and doped. This gave the assembly the appearance of a thick loop with a center post. ... The drive motor for rotating the loop antenna is contained in a box inside the fuselage just below the antenna and the large central unit for processing the radio signals was housed in the rear fuselage behind the rear cockpit bulkhead. The dynamotor power supply for the RDF system was likewise located in the rear fuselage. A visual indicator for flying along a directional radio range signal was mounted in the lower left corner of the instrument panel. The face of this instrument has an arc painted on it with characters for 'right' and 'left'. A needle indicated the relative position of the aircraft to the signal. One further control is a round switch box mounted next to the pilot's right shoulder. This was for switching the antenna's reception function between the communication radio and the RDF system. This was to allow the RDF operator to use the antenna to monitor AM radio broadcasts. Commander Fuchida used this feature on December 7 1941 as he approached Oahu. The regular music broadcast from Honolulu assured him that the American forces were unaware of his impending attack. I am informed that many pilots still engage in this practice to fight boredom on long flights.

The interesting thing about the Type 1-3 is that it was a copy of the Fairchild Aero Compass, manufactured in New York by the Fairchild Aerial Camera division of Fairchild Aircraft Company. The Zero coded AI-154, which was shot down at Fort Kamehmeha during the Pearl Harbor attack had a Fairchild-built direction finder Model RC-4, serial number 484 installed in it, as did the Zero, which was captured in the Aleutian Islands seven months later. Illustration 4 (see below) shows the faces of the Fairchild control box and one manufactured by the Naval Aerial Navigation Technical Depot. .... According to the TAIC manual these units operated in the 160 to 385 kilohertz range, which is in the Low to Medium Frequency bands. The selector switches on a captured unit are labeled from 170 to 1200 kHz, however. In the IJN the Type 1-3 was known as the 'Kruesi' after its designer, Geoffrey Kruesi of Dayton, Ohi
o.

part 22
Zero-Tooby--1024x550.jpg
 
RDF or radar first began to be fitted in British naval aircraft in spring 1941. 825 squadron in Victorious was lucky enough to have all its aircraft fitted with ASV II by the time of the Bismarck chase. Ark Royal's squadrons only had a few sets which went to flight leaders.

For undefined technical reasons it was not able to be fitted to Albacores until nearly the end of 1941. Even well into1942 it was not "pretty ubiquitous".
This is from Howse:

"The ASV I proved in service to be very fragile and its unreliability was not
helped by a lack of instructional handbooks and maintenance manuals at squadon
level. It also had a number of undesirable characteristics, not the least of which
was interference with the parent aircraft's W /T reception. By February 1940,
however, a full production model had been designed and engineered and two
firms were asked to produce 4,000 ASV Mark II sets, for delivery from 1 August
1940. Unfortunately, the Air Ministry bureaucracy failed to recognise the
importance of the programme and the formal order was not placed until April.
A month later, AI (air to air radar) production was given precedence over that of ASV, even to the
extent of 80 ASV I transmitters being diverted. By the end of 1940, Coastal
Command had only 49 aircraft equipped with ASV, while the Royal Navy had
only its trials aircraft. The Admiralty itself contributed to the delay in availability
of the ASV II, for it provided the basis of the type 286 radar, fitted in small surface
ships from the late autumn of 1940. Production increased rapidly early in 1941
and during the first three months of that year components for 1,000 complete sets
of ASV II were delivered to the Services.
ASV II remedied most of the pre-production Mark I's shortcomings and, with
minimal development, the Royal Navy's variant, ASV IIN, remained in front-line
service throughout the war. Operating in the ultra-high-frequency band, on
214MHz (the RAF's ASV 11 was tuned to 176MHz), with an initial peak power
output of 7kW, it could give a range of up to 15 miles against a medium-sized
ship and, under good conditions, up to 4 miles against a surfaced submarine.
Fitted to the inter-wing struts of the Walrus and Swordfish aircraft, the distinctive
splayed dipole antennae had little effect on the performance of biplanes which
rejoiced in the Service nicknames of 'Shagbat' and 'Stringbag'.
The first naval front-line unit to be fitted with ASV IIN was the spotterreconnaisance
catapult flight embarked in HMS King George V, which received
two radar-equipped Walrus amphibians in mid-March 1941. Other Home Fleet
Walrus flights quickly followed and as individual Swordfish were fitted with
radar they were delivered piecemeal to squadrons. In April 1941, 825 became the
first Swordfish squadron to be entirely re-armed with ASV Swordfish and it was
the nine aircraft of this unit which, flying from HMS Victorious to the south-west
of Iceland, first used ASV UN in anger, to locate and attack the Bismarck, just after
midnight on 25 May 1941...

...The intended replacement for the Swordfish, the Fairey Albacore, had been in
service since the summer of 1940 but had won its laurels in the eastern
Mediterranean without the benefit of ASV. Indeed, it was not until the end of 1941
that the problem of serious interference between the aircraft compass and the
radar alternator was solved. Thereafter, the aircraft were equipped as quickly as
possible and in March 1942 Victorious's two squadrons used their radar to good
effect in a torpedo attack on the Tirpitz which narrowly failed to score hits.
Priority for Albacore re-equipment went to the Home Fleet squadrons and thus,
when Formidable sailed for the Indian Ocean in February 1942, her squadron, like
all but a handful of the Albacores aboard the Indomitable, which was already on
station, lacked ASV and she had to 'borrow' a pair of ASV-fitted Swordfish. As
Admiral Somerville's plan for dealing with the Japanese carrier fleet relied
primarily on night search and strike, this was hardly a satisfactory state of
equipment. In the event, one of the Indomitable's radar-equipped Albacores did
make the only contact between Somerville's carriers and ship of the Japanese fleet,
as the latter was withdrawing beyond air torpedo striking range.
By mid-1942, sufficient ASV II sets were available to equip all embarked
aircraft...
"

However I suspect that it was a lack of incentive that delayed solving the Albacore issues as much as anything else.
 
Battle of Balkpapan
Some histories of this battle have things going a bit differently although the end result was the same.
the American destroyers
800px-USS_Parrott_%28DD-218%29_c1920.jpg

used torpedoes at fairly close range at times and did not use their guns (4 4in) until late.
They also had the older MK 12 torpedoes which lower performing and using lighter warheads at least seemed to work, of course Jan of 1942 the US had no idea of how the MK 14 would work let alone what the Japanese torpedoes would do.
this was pretty much an "old school" torpedo attack. Helped by the defending Japanese ships (at least the ones that actually engaged the US ships) being 750 ton (?) Patrol boats and not destroyers. Once the torpedoes were gone out of 3 of the ships they left (under orders) while 4th made one more attack to use the last of it's torpedoes and then used a gun attack on another two ships. It rejoined the other ships about 3 hours later.

A few reasons for the "old school" attack are that the 4in guns used 33lb shells and fired at about 8-9 rounds per minute. while useful this is not the firepower of more modern destroyers. By not using the guns the US ships were able to make several torpedo attacks on different targets at different times without getting into gun duals.
It appears that all of the transports such were sunk by torpedoes although several were damaged by gun fire as the US ships left the area. The US ships had little or no damage ?
 
I accidentally posted this into the other (Japanese aviation) thread, but it was meant for this one so I'm reposting here:

Ok so here are the 13 major surface actions of the early Pacific war, from Jan 1942 to August 1943. In cases where the range of the Japanese torpedoes played a factor, I put an asterix in red. This amounts to 5 of the 13.

Battle of Balkpapan
Jan 1942, Dutch East Indies
US destroyers caught Japanese invasion fleet by surprise at night, launched torpedoes but the torpedoes failed. (Correction per SR6 above- apparently the US mark 12 torpedoes did work after all and are what sunk the Japanese transports)
Result: 4 IJN transports sunk. US victory.

Battle of Badung Strait
Feb 1942 - Dutch East Indies near Bali
After an ineffectual exchange of gunfire from 3 allied (Dutch, English and US) cruisers and 7 destroyers, 4 Japanese destroyers launched torpedoes from ~ 1,000 yards.
Result: 2 Allied destroyers sunk (one was heavily damaged and later scuttled). Japanese victory.
Detailed account here

Battle of Java Sea *
Feb 1942, Dutch East Indies near Java
Large, 7 hour long daylight encounter between IJN force (2 x CA, 2 x CL, 14 x DD) and Dutch-American-British fleet (2 x CA, 3 x CL, 9 x DD). Both gunfire and torpedoes were exchanged, with the Japanese CL Naka starting the engagement with the launch of type 93 torpedoes. IJN launched three large spreads of torpedoes at ranges between 14,000 - 28,000 yards. One IJN destroyer launched from 6,500 yards. The range was beyond what the Allies thought was effective range, and they thought they were being attacked by submarines. Only the third wave, launched from 14,000 yards, scored hits, but the hits were telling.
During the battle the Japanese launched 152 type 93 torpedoes, mostly from long range, and got 3 hits. They also shot 1,619 8" shells and got 5 hits. The Allies shot a similar number of shells and got only one direct hit. Allied torpedoes made no hits.
Result: 2 Allied CL and 3 Destroyers sunk, 1 Japanese Destroyer damaged. Japanese victory.
Detailed account here

Battle of Sunda Strait
Feb 1942, Dutch East Indies near Java
Japanese vessel DD Harukaze launched nine type 93 torpedoes from 3,000 yards. Perth (CA) and Houston (CA) ultimately sunk.
Result: Japanese victory

Battle of Bawean island (aka "Second battle of the Java Sea")
March 1942, Dutch East Indies near Java
Japanese attacked crippled RN CA Exeter and two US destroyers. Initial exchange was with cruiser gunfire, then torpedoes at short range.
Result: All Allied vessels sunk. Japanese victory.

Battle of Savo Island *
August 1942 - Solomon Islands
First attack of the battle was as Chokai launched torpedoes at 17,000 yards at 01:30. Five minutes after that Chokai opened fire with 8" guns. Canberra was hit by twenty 8" shells and one torpedo - but it was an American one! Chicago was then hit by a torpedo. This may have been from Chokai.
Result: 4 Allied (US and Aus) cruisers sunk, other ships damaged. 2 Japanese cruisers damaged. Japanese victory.
Detailed account here

Battle of Cape Esperance
Oct 1942 - Solomons
USN detected Japanese with radar from the Helena. There was an exchange of gun and torpedo fire from short range. Some friendly fire on the US side. Damage was mostly by gunfire, but one US torpedo from Buchanan hit Furutaka and crippled her. Furutaka was also further damaged by her torpedoes catching fire.
Result: 1 Japanese CA sunk, 1 DD sunk, 1 CA heavily damaged. USN Victory

Naval Battle of Guadalcanal (first)
Nov 1942 - Solomons
Japanese and US fleet encountered each other at short range. Confused action with torpedoes and gunfire on both sides. Most US losses due to torpedoes.
Multiple Allied ships crippled, one Japanese Battle cruiser crippled and then sunk. Japanese Victory

Naval Battle of Guadalcanal (Second)
Nov 1942 - Solomons
Washington with the help of radar and visual sighting opens fire from 11,000 yards and sinks Kirishima. US destroyers hit by gunfire and torpedoes.
Result: Japanese battleship and one destroyer sunk, three US destroyers sunk, US Battleshp South Dakota damaged. USN victory

Battle of Tassafronga *
Nov 1942- Solomons
Eight Japanese destroyers vs 4 US heavy cruisers, 1 light cruiser, and 6 US destroyers. US commanders believed that a range of 12,000 yards was safely beyond torpedo range. Japanese destroyers launched torpedoes from 9 - 14,000 yards. US destroyers requested permission to launch torpedoes at 7,000 yards which is initially denied as being too far. US finally launched torpedeos at 5,000 yards. Gunfire from heavy cruisers opened up at ~ 9-10,000 yards. All Japanese damage was due to torpedoes.
Result: US gunfire sunk one IJN destroyer. One US CA sunk and 3 heavily damaged (blown off bows etc.). Japanese Victory.
Detailed account here

Battle of Komandorski Islands
March 1943 - Aleutians
Daylight surface battle with heavy cruisers on both sides, US had 2 CA and 2 CL, Japanese had one of each, both sides had 4 destroyers. Gunfire exchange at long range. Some hits with 6 inch guns. Most damage was by 8" guns. Japanese launched at least 30 torpedoes but all missed. US launched torpedoes from 10,000 yards but also missed.
Result: One USN CA heavily damaged, one IJN CA moderately damaged, but IJN fleet retreats. USN Victory.

Battle of Kula Gulf *
July 1943 - Solomons
Both Japanese and Americans had radar. Three Japanese DDs launch first volley of 14 torpedoes from 'long range' (Wikipedia says 20km). One hit US DD Strong. Wikipedia says this was the longest successful torpedo attack of WW2. USN was still not expecting torpedoes to travel this far. US ships open fire from 15km, sinking a Japanese destroyer. Helena was out of flashless powder, and was targeted by 16 torpedoes from Suzukaze and Tanikaze, being hit and sunk by at least two type 93 torpedoes. They took light damage from gunfire. Another Japanese DD was grounded and later abandoned.
Result: One USN CL sunk, 2 IJN DDs sunk. Japanese land some troops. Inconclusive.
Detailed account here The Wiki also has a lot on this one.

Battle of Kolombangara (aka Second Battle of Kula Gulf) *
July 1943 - Solomons
Small battle with three (US and New Zealand) light cruisers with 10 destroyers intercepting a 'Tokyo Express' force of one CL and 9 destroyers. Both US and Japanese launched torpedoes at roughly 10,000 yards, but the Japanese launched first and then turned away. US still thought Japanese torpedo range was about 10,000 yards. Both sides exchanged gunfire at 9,000 yards Spotting aircraft were being used to help sight in the rounds. US launched a second volley of torpedoes from 7,900 yards. Japanese light cruiser Jintsu was hit by gunfire and at least two US torpedoes, and sunk. New Zealand cruiser Leander was hit by a type 93 torpedo and badly damaged, as was DD Gwin which sunk.
Result: One US destroyer sunk, New Zealand cruiser badly damaged, 1 Japanese light cruiser sunk.
Detailed account here

Battle of Vella Gulf
August 1943 - Solomons
Japanese evaded 30 torpedoes from US PT boats (PT 109 is sunk in a collision). Four Japanese destroyers are then intercepted by six US destroyers which detect them with radar. US commander (Moosbrugger) disabled the magnetic detectors and set this torpedoes to run at 5 feet depth and 36 knots. With these modifications he trusted his torpedoes and decided to use them in preference to long range gunfire, against advice of his superior. He also had good radar. US destroyers fired 24 torpedoes at 6,300 yards. Only one Japanese destroyer returned fire.
Result: Three Japanese destroyers sunk. US victory.
Detailed account here
 
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We are debating a lot about a no European war Scenario however the two are linked.

If there is no European war the Japanese would probably not have attacked. Tensions in the area were going up considerably in late 30s.

For the Japanese to get to their Dec 1941 start positions might have triggered armed confrontations with France if France was not taken out by Germany.
The British had taken a number of ships/submarines out of Singapore.
The Dutch were trying to build up naval strength in the area. Also stopped by the Germans.

The actual triggers (Japanese actions) for the US embargoes don't happen until after the Battle for France Although the US was not happy with the Japanese actions in 1939 and the US was moving towards the sanctions in 1939. I have no idea if the Japanese would have backed off with the US imposing trade sanctions and the British, Dutch and France ( the major colonial powers in the area) not being taken out or otherwise busy with Germany.

A likely scenario (to me anyway) is that Germany goes to war in 1939, France and Holland get overrun, somewhat historically, France lasts a few weeks longer? Some French colonies join the Free French?
Which emboldens Japan to take some the steps or at least not back down in 1940.
Italy is the wild card. If Italy can be taken out in late 1940/or early 1941 or at least neutralized the British can free up a lot of stuff from the Med to go to the Far East in time to actually do things in Malaya. But if the Japanese don't back down the embargo train keeps going forward triggering the Japanese attack in the winter of 1941/42.
Crate loads of butterflies here.
Doesn't do a lot for the British carrier aviation.
Does free up a lot of subs, cruisers and Destroyers which does change how such a war would be fought.
There is no climatic battle like the US sailing across the Pacific to save the Philippines.

There is a large campaign for the Japanese to try to take Burma (Rangoon) to isolate the Chinese Army. But aside from aircraft that is not a good use of Japanese ships.
If Japan tries to ignore the Philippines to keep the US out of the battle (and the US is the main driver of the embargo but they are running out of things to embargo) it is the Japanese that have to keep a lot of ships standing by incase the US does join in.

A lot may depend on how much "stuff" Britain can get into Malaya and how much stuff they can get into Java/Indonesia/New Guinea and turn this into a supply war.

Edit> The Greek/Crete Campaign cost the British 25-30,00(more?) troops. about 100 tanks, artillery??? planes and ships.

This is another crate of butterflies. But the investment in Greece may have cost the British the ability to capture Libya in late winter, early spring of 1941.
 
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We are debating a lot about a no European war Scenario however the two are linked.

If there is no European war the Japanese would probably not have attacked. Tensions in the area were going up considerably in late 30s.

For the Japanese to get to their Dec 1941 start positions might have triggered armed confrontations with France if France was not taken out by Germany.
The British had taken a number of ships/submarines out of Singapore.
The Dutch were trying to build up naval strength in the area. Also stopped by the Germans.

The actual triggers (Japanese actions) for the US embargoes don't happen until after the Battle for France Although the US was not happy with the Japanese actions in 1939 and the US was moving towards the sanctions in 1939. I have no idea if the Japanese would have backed off with the US imposing trade sanctions and the British, Dutch and France ( the major colonial powers in the area) not being taken out or otherwise busy with Germany.

A likely scenario (to me anyway) is that Germany goes to war in 1939, France and Holland get overrun, somewhat historically, France lasts a few weeks longer? Some French colonies join the Free French?
Which emboldens Japan to take some the steps or at least not back down in 1940.
Italy is the wild card. If Italy can be taken out in late 1940/or early 1941 or at least neutralized the British can free up a lot of stuff from the Med to go to the Far East in time to actually do things in Malaya. But if the Japanese don't back down the embargo train keeps going forward triggering the Japanese attack in the winter of 1941/42.
Crate loads of butterflies here.
Doesn't do a lot for the British carrier aviation.
Does free up a lot of subs, cruisers and Destroyers which does change how such a war would be fought.
There is no climatic battle like the US sailing across the Pacific to save the Philippines.

There is a large campaign for the Japanese to try to take Burma (Rangoon) to isolate the Chinese Army. But aside from aircraft that is not a good use of Japanese ships.
If Japan tries to ignore the Philippines to keep the US out of the battle (and the US is the main driver of the embargo but they are running out of things to embargo) it is the Japanese that have to keep a lot of ships standing by incase the US does join in.

A lot may depend on how much "stuff" Britain can get into Malaya and how much stuff they can get into Java/Indonesia/New Guinea and turn this into a supply war.

Edit> The Greek/Crete Campaign cost the British 25-30,00(more?) troops. about 100 tanks, artillery??? planes and ships.

This is another crate of butterflies. But the investment in Greece may have cost the British the ability to capture Libya in late winter, early spring of 1941.

This is all quite interesting, (sincerely) but the point of the thread was really just to compare and contrast the naval resources, fleets and fighting machines (in the air, on the water, under the water etc.) of the two nations. And I think it's already pretty clear: The IJN was superior, even if you brought most of the RN over to contend with them. Numbers are really the main advantage the British have. Radar and functional torpedoes will help, superior cryptography will help more, but not enough to overcome the clear and blatant inferiority in aircraft, and (the more arguable but I think also pretty clear) disadvantage in warships.

And the whole point of that is just to show that the Japanese were not, in fact behind technologically or militarily. In 1941 they probably had the best, (if not the largest) navy in the world. They did gradually fall behind and stumbled in some of their weapon development in 1943, but they were still quite formidable on the world stage even into 1944, probably until after the Battle of Leyte Gulf. Only the USN could stand up to them (with the help of USAAF and RAAF air assets, and RN and RAN as well). Victory over the Japanese was neither easy nor (in my opinion) a foregone conclusion. Yes they looked weak in 1945. They had lost the war by then. Most of their fighting age men, cities, and all of their major war machines had been annihilated.

They did not look so weak in 1941, 1942, or even 1943. To the contrary, they looked terrifying.

As for scenarios, it does seem like oil in Brunei and / or Dutch East Indies would be pretty tempting. I think that was the whole point behind their attempt to push into Russian Siberia prior to Kalninin Gol (oil, I mean). Rubber in Indochina looks pretty tempting too. Bauxite (aluminum ore), copper and iron etc. in Malaya as well.
 
Victory over the Japanese was neither easy nor (in my opinion) a foregone conclusion.

I don't agree. Absent a negotiated peace by 1942, Japan was toast. And the very nature of the attack on PH meant that America would not negotiate. The Two-Ocean laws and the rearmament of the Army and Air Corps were harnessing America's latent industrial strength at a time when the Japanese economy was about maxed out.
 

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