Challenge: Better japanese performance WWII

I've been neglecting the Kamikaze part of this thread. Time to remedy that.

elkarlo...

First, resorting to such attacks brings back the Japanese problem of losing pilots faster than they can be replaced. Every professional who does this is not going to be around for many other operations.

True. I did have training more pilots starting before Pearl Harbor as one of my suggestions for the Japanese, but I wasn't thinking in terms of using them for kamikaze missions. More on that later.

Second, it implies acceptance by Japan's leadership astoundingly early that the situation is so hopeless that such attacks must be considered.

It does take a shift in Japanese thinking, but not necessarily one of realizing that the situation was hopeless. The Japanese were incredibly cavalier with the lives of their soldiers early on, as evidenced by their practice of sending 'human bullets' against Soviet tanks as early as Nomanham.

Pilots were initially in a different category because of their elite status as aerial samurai. The shift in Japanese thinking would have needed to be something along the line of deciding that people not as elite as those chosen to be pilots could be of use as flying human bullets. They were certainly callous enough to do that. I'm not sure they would have done so early enough to have made a difference, at least partly because their aircraft production wasn't high enough to make one-ways worthwhile until later.


Third, this requires the Japanese leadership to somehow conclude that their torpedo and dive bomber pilots have suddenly become incapable of doing the job, this after several sweeping victories early in the war.

True. Kamikaze attacks are less likely during the "victory disease" phase of the war. They become more likely after Midway. On the other hand, people like Yamamoto were quite aware of how much more the Japanese had bitten off than they could chew. I could see him thinking in terms of what happens after the six months he predicted that the Japanese would run amok.

Fourth, the idea of concentrating on capital ships simply won't work. Japan had no intention of sending out thousands of aircraft to target any but the most lucrative targets but massive numbers were shot down by American anti-aircraft and fighter cover trying to get to such targets and many of those which may have gone for the first available target were likely damaged or low on fuel or had other sound reasons to assume that a smaller ship on the perimeter was the only target they could hope to reach.

Informing the pilots that they must go for only certain ideal targets will cause grave suspicion that the kamikazes have been dying in droves for little success and then lead to even more being shot down as they search for something on the list of acceptable targets.
Yeah. Going strictly after capital ships has it's downside.


DaleCoz, except that once the USN could field a substantial force after the battle for Guadalcanal the losses in the air favored the USN to a massive degree, such that a handful of suicide planes in the hands of marginally competent pilots are extremely unlikely to achieve anything in the face of USN airpower and anti-aircraft. For that matter, why would a dozen suicidal incompetents who have to actually touch the target to achieve anything be more likely to succeed than scores or hundreds of professional torpedo and dive bomber pilots available for a single battle?

As I recall Japan threw away @5000 aircraft to sink 34 American ships off Okinawa, a single light carrier being the worst loss. That isn't trading 12 for a carrier but 150 for any possible target.

Again, I agree with most of what you're saying here. At some point the US preponderance in--well pretty much everything--meant that the kamikaze tactic (and pretty much anything else the Japanese could do) was futile, though the kamidazes did give the US fits. How many ships did the US lose to conventional Japanese attacks off of Okinawa?

Where this tactic would be helpful would be during the period between mid-1942 and mid-to-late 1943 where the US/Japanese balance of power wasn't too far tilted toward the US, and when the Japanese still had significant conventional naval airpower.

Another possible use, though I haven't thought this through completely, is for surprise raids on targets that are out of range of conventional attacks. No need to return means double the effective range, though that sort of thing would require a fair amount of training.


As for this discussion about the search function, hasn't that already been done to death?;)

I'm done with it.;)
 
One of the simplest ways for the Japanese to do better in WW2 is for Germany to decide that Japanese military strength is likely to be good for Germany and that some risks to secrecy must be taken and some profits deferred in order to increase Japanese military strength. Thus, for example, Hitler orders that Japanese officers be offered Germany technology at low cost and given as much help as possible in utilizing German ideas.

Ideally this should start from the Anti-Comintern Pact of 1936 but even as late as 1940, we could imagine the raider Komet arriving in Japan in September 1940 after being loaded with the latest radar and sonar, machine tools for making fuel injection equipment for aero-engines [1], a DB-601E [2] engine (assuming those were bench running) and a prototype Fw190, magnetic and acoustic mines (possibly magnetic were on board OTL) and no doubt many other neat ideas such as the shaped charges used at Eben Email. They could even put a He 178 prototype on board and some details of the Fritz-X and Hs-293 projects. Giving details of how sorting machines could be used to attack the British naval codes might also have been helpful if the IJN could take a hint about the possibility of a similar attack on JN 25.

Naturally if we go back to 1936 or even earlier there is time to build a few synthetic oil plants or to use the German ST 52 steel to enable warships to be easily welded [3].

1. Daimler Benz had licensed the DB 601 to both the IJA and the IJN (separately!!!) but Bosch had refused to supply details of how to make the fuel injectors. Thus the injectors for the Atsuka were hand made by Mitsubishi. Mitsubishi added fuel injection to the 14 cylinder Kinsei and the first application, the Ki-46 III, was introduced in 1943. However, production of the Ha 112 II or Kinsei 60 series was so slow that it was 1945 before it was tried in two prototype A6M8 Zeros.
2. The DB 601E had repositioned sparking plugs and altered valve timing allowing the max revs to increase and power was 1350 hp rather than the 1175 hp of the DB 601 Aa copied by Japan with the same 87 octane. On reflection, the Japanese would have hit problems with the bearings, so they needed to realise that shell bearings could replace the DB 601's roller bearings as DB later did with late war 605s. The extra power would have been useful for the Ki-61 for example.
3. Dale had earlier suggested adopting welded mass production of ships but there was a problem for the British and Japanese that D steel was hard to weld. Mild steel was used in the Tachibana class and some British constructors believed the easier welding of mild steel made up for the heavier weight needed to give the same strength. Unfortunately, ST 52 contained more nickel than D steel, so perhaps the IJN might not be enthusiastic.
 
One of the simplest ways for the Japanese to do better in WW2 is for Germany to decide that Japanese military strength is likely to be good for Germany and that some risks to secrecy must be taken and some profits deferred in order to increase Japanese military strength. Thus, for example, Hitler orders that Japanese officers be offered Germany technology at low cost and given as much help as possible in utilizing German ideas.

Ideally this should start from the Anti-Comintern Pact of 1936 but even as late as 1940, we could imagine the raider Komet arriving in Japan in September 1940 after being loaded with the latest radar and sonar, machine tools for making fuel injection equipment for aero-engines [1], a DB-601E [2] engine (assuming those were bench running) and a prototype Fw190, magnetic and acoustic mines (possibly magnetic were on board OTL) and no doubt many other neat ideas such as the shaped charges used at Eben Email. They could even put a He 178 prototype on board and some details of the Fritz-X and Hs-293 projects. Giving details of how sorting machines could be used to attack the British naval codes might also have been helpful if the IJN could take a hint about the possibility of a similar attack on JN 25.

That would take a lot more trust and cooperation than the Axis powers were likely to exhibit, but given a bit more realistic view of the odds they were up against....extremely unlikely but not not completely out of bounds for an alternate history site. I'm not sure your choices are all going to be useful for the Japanese. Their need for very long range in their planes colored their decisions on aircraft engines and design. Getting German aircraft engines to the Italians earlier might be more directly useful to the Germans. Now if the Germans and Italians got their hands on Long Lance torpedoes...that could be fun, though I'm not sure westerners would accept something that dangerous on ships or subs.

Naturally if we go back to 1936 or even earlier there is time to build a few synthetic oil plants or to use the German ST 52 steel to enable warships to be easily welded [3].
Yeah, cooperation on synthetic oil plants would probably help.


3. Dale had earlier suggested adopting welded mass production of ships but there was a problem for the British and Japanese that D steel was hard to weld. Mild steel was used in the Tachibana class and some British constructors believed the easier welding of mild steel made up for the heavier weight needed to give the same strength. Unfortunately, ST 52 contained more nickel than D steel, so perhaps the IJN might not be enthusiastic.
Ah. I wasn't aware of that issue.
 

Paul MacQ

Donor
One of the simplest ways for the Japanese to do better in WW2 is for Germany to decide that Japanese military strength is likely to be good for Germany and that some risks to secrecy must be taken and some profits deferred in order to increase Japanese military strength. Thus, for example, Hitler orders that Japanese officers be offered Germany technology at low cost and given as much help as possible in utilizing German ideas.

Ideally this should start from the Anti-Comintern Pact of 1936 but even as late as 1940, we could imagine the raider Komet arriving in Japan in September 1940 after being loaded with the latest radar and sonar, machine tools for making fuel injection equipment for aero-engines [1], a DB-601E [2] engine (assuming those were bench running) and a prototype Fw190, magnetic and acoustic mines (possibly magnetic were on board OTL) and no doubt many other neat ideas such as the shaped charges used at Eben Email. They could even put a He 178 prototype on board and some details of the Fritz-X and Hs-293 projects. Giving details of how sorting machines could be used to attack the British naval codes might also have been helpful if the IJN could take a hint about the possibility of a similar attack on JN 25.

Naturally if we go back to 1936 or even earlier there is time to build a few synthetic oil plants or to use the German ST 52 steel to enable warships to be easily welded [3].

1. Daimler Benz had licensed the DB 601 to both the IJA and the IJN (separately!!!) but Bosch had refused to supply details of how to make the fuel injectors. Thus the injectors for the Atsuka were hand made by Mitsubishi. Mitsubishi added fuel injection to the 14 cylinder Kinsei and the first application, the Ki-46 III, was introduced in 1943. However, production of the Ha 112 II or Kinsei 60 series was so slow that it was 1945 before it was tried in two prototype A6M8 Zeros.
2. The DB 601E had repositioned sparking plugs and altered valve timing allowing the max revs to increase and power was 1350 hp rather than the 1175 hp of the DB 601 Aa copied by Japan with the same 87 octane. On reflection, the Japanese would have hit problems with the bearings, so they needed to realise that shell bearings could replace the DB 601's roller bearings as DB later did with late war 605s. The extra power would have been useful for the Ki-61 for example.
3. Dale had earlier suggested adopting welded mass production of ships but there was a problem for the British and Japanese that D steel was hard to weld. Mild steel was used in the Tachibana class and some British constructors believed the easier welding of mild steel made up for the heavier weight needed to give the same strength. Unfortunately, ST 52 contained more nickel than D steel, so perhaps the IJN might not be enthusiastic.

The Japanese already ordered He100d Tooling and these did not get to Japan due to start of the war,

Many respects a far reaching design not just in performance bit also for the sake of ease of Manufacture, One of the failing points of the earlier He112 against the BF109 was, it took long to make. The structure of the HE100d had as many productions short cuts possible was built for mass production.

Early Zeroes being a complete bitch top manufacture 10s of thousands more Rivets than late war designs. Very much hand built sports car.

Now getting the Japanese a Fighter with at least one cannon and a cople MG's to the army that can do over 400 mph and had reasonable range that is takes less than 1 quarter the man hours of a Zero would be a good start

Man hours to produce early war BF109 was 6,000 man hours Henkel’s target for the HE100 was 2/3 rds that. The Mitsubishi Zero was and extremely complicated structure to make it as incredibly light as possible.

The Ki 44 would have been a good candidate to replace with a Japanese HE100D.

Late war with something like the simple R4M rocket that is a very simple weapon that has no tech in it the Japanese do not have access too. even lightly gun arm aircraft like a Ki43 can take down the likes of a B17 and Faster flyers have been given much better chances against a B29

http://en.wikipedia.org/wiki/R4M_(rocket)
http://www.stormbirds.net/tech_r4m_rocket.htm
 
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IMO what really killed any chance of Japanese success was their decision to take China through brute force. Once that happens, the IJA gets stuck fighting against an undefeatable enemy, and because they themselves cannot be defeated by the KMT, this only serves to prevent any initiative for exit.
And Japan's war in China just leaves them weak on a global scale - the USA will take advantage of the situation by supplying China and santioning Japan, Russia is a constant threat to be defended against, and the war causes problems domestically (i.e. all the manpower being killed off, leading to economic and demographic issues).

So you have to ensure that Japan does not plunge itself head-on into China proper. Like I suggested in this thread, you could have Japan try more subtle means of winning China (perhaps the KMT) over to become a puppet ally, while making sure that China can never be fully united and thus go its own way (perhaps this could be done by always having a military presence in trouble areas, annexing small regions (such as Hainan) for itself, etc.
It's a bit tricky to have a KMT allied to Japan as a puppet, but there was a lot of infighting in China and it seems to me that the Japanese would have an easier time manipulating Chinese politics than doing what they did historically.
 
IMO what really killed any chance of Japanese success was their decision to take China through brute force. Once that happens, the IJA gets stuck fighting against an undefeatable enemy, and because they themselves cannot be defeated by the KMT, this only serves to prevent any initiative for exit.
And Japan's war in China just leaves them weak on a global scale - the USA will take advantage of the situation by supplying China and santioning Japan, Russia is a constant threat to be defended against, and the war causes problems domestically (i.e. all the manpower being killed off, leading to economic and demographic issues).

So you have to ensure that Japan does not plunge itself head-on into China proper. Like I suggested in this thread, you could have Japan try more subtle means of winning China (perhaps the KMT) over to become a puppet ally, while making sure that China can never be fully united and thus go its own way (perhaps this could be done by always having a military presence in trouble areas, annexing small regions (such as Hainan) for itself, etc.
It's a bit tricky to have a KMT allied to Japan as a puppet, but there was a lot of infighting in China and it seems to me that the Japanese would have an easier time manipulating Chinese politics than doing what they did historically.

I doubt that the Japanese could make the core of the KMT a puppet regime. They could probably turn some of the northern warlords into puppets with the right manipulation. In the period before all-out war they could probably have managed a kind of tacit alliance with the Nationalists where the Nationalists got a free hand against the Communists and the Japanese got a free hand against the northern warlords as long as the Japanese didn't grab something as symbolically important as Peking. The Nationalists claimed to rule all of China and letting the Japanese take Peking without a fight would have scuppered that pretension.

Later on, a fairly major former KMT figure did form a puppet government under the Japanese, but was given so little real power for his trouble that there was little incentive for other figures to join him. I suppose giving him more real power might have made a difference.
 
There is a very minor way for Germany to have helped Japan at no cost in 1939. Had Germany on 24th August 1939 ordered those merchant ships that could not return to Germany to sail to a Japanese controlled area, Japan would have gained some extra ships and many would not have been captured and used by the Allies. For example, I have listed below some ships, with the gross registered tonnage in brackets, that were left in ports around the Indian Ocean. The list is not complete and there were also many (about 85 ships?) around the Americas.

Captured or scuttled 10.5.1940 in Netherlands East Indies
Nordmark (7749), Rendsburg (6200), Vogtland (7106), Bitterfeld (7659), Franken (7789), Rheinland (6622), Wuppertal (6737), Soneck (2191), Cassel (6047), Essen (5158), Naumburg (5878), Friderun (2464), Scheer (8142), Sophie Rickmers (7033), Moni Rickmers (5272), Wasgenwald (4990), Werdenfels (6318), Lindenfels (8457), Stassfurt (7395)

Captured or scuttled March/April 1941 Italian East Africa
Oder (8516), Bertram Rickmers (4188), Crefeld (8045), Frauenfels (7487), Gera (5155), Lichtenfels (7566), Liebenfels (6318), Oliva (7885), Niobe (1765)

Captured or scuttled 25.08.41 Iran
Hohenfels (7682), Marienfels (7575), Sturmfels (6288), Weissenfels (7861), Wildenfels (6224)

Attacked at Goa 09.03.43
Braunfels (7846), Drachenfels (6342), Ehrenfels (7752)

Even if Germany had not got its act together in 1939, they should have tried to sell the ships in the Netherlands East Indies to Japan before May 1940 (what can they lose?).

Note that Italy also lost a similar number of ships in June 1940.

Everyone is going to say that this is only going to give the Japanese the equivalent of the tonnage lost in under two months during 1943-4, so it makes little difference. However, the ships in the NEI alone could deliver one IJA division in 1942, for example, to Port Moresby at the same time as the Rabaul invasion at the end of January 1942 covered by the Kido Butai.

ps. Above is mostly recycled from http://forum.axishistory.com/viewtopic.php?f=11&t=159856&p=1419180#p1419180
 
Where this tactic would be helpful would be during the period between mid-1942 and mid-to-late 1943 where the US/Japanese balance of power wasn't too far tilted toward the US, and when the Japanese still had significant conventional naval airpower.
And the potential Kamikaze pilots still had the skills to consistently hit ships.The Japanese, however, would have needed to build a high quality Kamikaze plane.

Japanese planes made poor Kamikaze air craft because they were light, un armoured and carried a minimum bomb load. A design centered around an american heavy fighter such as the P-47 "jug" would be ideal. Skilled kamikaze pilots flying a Japanese jugs would have made a huge difference tactically in 1942 to late 43.
There is a very minor way for Germany to have helped Japan at no cost in 1939. Had Germany on 24th August 1939 ordered those merchant ships that could not return to Germany to sail to a Japanese controlled area...
That is very interesting and really illustrates that the Germans and Japanese were more acquantiances than allies.
 
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Paul MacQ

Donor
And the potential Kamikaze pilots still had the skills to consistently hit ships.The Japanese, however, would have needed to build a high quality Kamikaze plane.

Japanese planes made poor Kamikaze air craft because they were light, un armoured and carried a minimum bomb load. A design centered around an american heavy fighter such as the P-47 "jug" would be ideal. Skilled kamikaze pilots flying a Japanese jugs would have made a huge difference tactically in 1942 to late 43.

That is very interesting and really illustrates that the Germans and Japanese were more acquantiances than allies.

So the Japanese using something like German guided weapons is out FritzX had it's issues, Still think far better track the Kamikaze.
http://en.wikipedia.org/wiki/Henschel_Hs_293
http://en.wikipedia.org/wiki/Fritz_X
Or even better a Weapon like the US BAT
http://en.wikipedia.org/wiki/Bat_(guided_bomb)

Something that could be used out of the Range of the Proximity Fuse Ammo.

Or for that matter how about a US POD and no Proximity fuse in the first place.
 
Both the IJN and the IJA designed guided missiles http://www.fischer-tropsch.org/prim...Reports/USNTMJ-200D-0550-0575 Report 0-02.pdf. However, they seem to have only started working on them seriously from perhaps 1943. The Army's I-GO series (for some photographs see http://lemairesoft.sytes.net:1945/weben/avion/avion2/449.html or http://www.ww2aircraft.net/forum/weapons-systems-tech/hiryu-projects-9557.html) were produced and tested in some numbers. However, by 1945 it was clear that a weapon launched and guided from a bomber such as the Ki-67 Hiryu would not work because the launching aircraft would be shot down as had generally occurred in the case of the Yokosuka MXY-7 Ohka.

Thus infra-red guidance was tried in the Ke-Go missiles http://www.fischer-tropsch.org/prim...ports/USNTMJ-200J-0032-0065 Report X-02-1.pdf which could be used at night. The US investigators were quite impressed by the Japanese work but Yagi Hidetsugu was very critical of the officers unwillingness to reveal anything to the engineers asked to design the components, so that the components frequently did not work together (see “Japan in the Shadow of Big Science” by Walter E. Grunden, page 144). Another source is “Japanese Special Attack Aircraft and Flying Bombs” by Ryusuke Ishiguro and Tadeusz Januszewski.

For a POD, I was hoping that finding out about German projects such as Fritz-X, which started in 1938, might inspire the IJN to develop something that could be used in 1942 when the launching aircraft could either be escorted or might evade interception. However, there might be difficulties as most of these missiles need good gyroscopes and Japan had some problems such as difficulty in making small ball bearings to the precision achieved by the Swedish SKF. Interestingly, there had been some effort to persuade SKF to set up a plant in Manchukuo. Perhaps Japan should have offered good terms if SKF would build a plant in Japan.
 
For a POD, I was hoping that finding out about German projects such as Fritz-X, which started in 1938, might inspire the IJN to develop something that could be used in 1942 when the launching aircraft could either be escorted or might evade interception. However, there might be difficulties as most of these missiles need good gyroscopes and Japan had some problems such as difficulty in making small ball bearings...

In addition to the engineering difficulties, the U.S. and British were very strong in electronics and the possibility of rapidly developed counter measures was very strong.

Subjective considerations aside, I think the only gudiance system guaranteed to hit american ships in 1942 / 43 was a skilled Japanese pilot. A heavy fighter (Corsair or Jug) would also carry a huge, ship destroying war head.
 
In addition to the engineering difficulties, the U.S. and British were very strong in electronics and the possibility of rapidly developed counter measures was very strong.

Subjective considerations aside, I think the only gudiance system guaranteed to hit american ships in 1942 / 43 was a skilled Japanese pilot. A heavy fighter (Corsair or Jug) would also carry a huge, ship destroying war head.

The Allies did tend to frustrate the Germans with their countermeasures. "We spend years developing this uber-weapon and they counter it with something cheap and simple."
 
Of course the US had a lot of spare capacity in almost every category by late 1944-45. A friend of mine used to respond to Axis win scenarios by saying "And then the US takes its other hand out from behind its back."
 

elkarlo

Banned
Let me add: develop an effective naval AA gun. OTL, all their ships carried a 75mm that was pretty much worthless.




Doug M.

The Japanese had terrible AA guns on their ships. Their 20mm and the such had a horrible rate of fire. They also didn't have any 5in that could elevate to be AAA AND reload at that elevation.
 
....

Let me add: develop an effective naval AA gun. OTL, all their ships carried a 75mm that was pretty much worthless.
.....
Doug M.
The Japanese had terrible AA guns on their ships. Their 20mm and the such had a horrible rate of fire. They also didn't have any 5in that could elevate to be AAA AND reload at that elevation.

I was going to say that no Japanese ship carried a 75 mm A.A. Gun but that is not quite true. The IJA's 75 mm type 88 http://en.wikipedia.org/wiki/Type_88_75_mm_AA_Gun was quite frequently mounted on merchant ships taken into Army service. The Type 88 was accepted in (yes you guessed) 1928, so by 1941 it was quite long in the tooth. The IJA planned to replace it with the Type 99 (accepted in 1939) http://en.wikipedia.org/wiki/Type_99_88_mm_AA_Gun which was reverse engineered from German guns captured in China. The IJA later reverse engineered the Bofors 75 mm http://en.wikipedia.org/wiki/Type_4_75_mm_AA_Gun. The IJA also designed larger 12 cm and 15 cm AA guns although these were only built late in the war.

The IJN meanwhile was producing its own wide range of heavy AA guns including 12 cm http://www.navweaps.com/Weapons/WNJAP_47-45_10ns.htm, 12.7 cm http://www.navweaps.com/Weapons/WNJAP_5-40_t89.htm, 10 cm http://www.navweaps.com/Weapons/WNJAP_39-65_t98.htm and 7.62 cm http://www.navweaps.com/Weapons/WNJAP_3-60_t98.htm. The 3rd year 12.7 cm http://www.navweaps.com/Weapons/WNJAP_5-50_3ns.htm was a dual purpose gun on most Japanese destroyers. This gun could elevate to 75 degrees in the later destroyers but is the gun perhaps referred to above that could not be loaded at high angle. The train and elevation rates of destroyer turrets were also poor for AA use. A new 12.7 cm gun was being designed but never made it into service http://www.navweaps.com/Weapons/WNJAP_5-50_t1.htm.

So what can we conclude about heavy AA guns?

Firstly, the IJA might have been wiser to have bought a licence from Germany for the 88 mm in the conventional way. They might even have acquired a good anti-tank gun at the same time! I have even heard that production of the 88 mm was stopped by the Tripartite Pact as the Germans objected to the Japanese production but I have not found evidence except that the Bofors copy was produced later. However, that 75 mm was also intended for anti-tank applications.

Secondly, the IJA and IJN could have saved themselves some work by cooperating. For example, both were producing 12 cm guns for land use over 1943-5 independently.

The IJN slightly lost in terms of performance by introducing their standard 12.7 cm gun much earlier than the British 4.5” and lost more relative to the USN's superb 5”/38. However, it was not hugely inferior to the British gun, which was introduced in 1938. They also lost by having a heavy secondary armament on their battleships which was intended to engage surface targets. Perhaps the 12.7 cm Type 1 should have been designed at a higher priority. This seems to have followed a similar logic to the USN's 5”/54, throwing a lighter 27 kg shell to 25,800 yards compared to 31.448 kg to 25,909 yards for the 5”/54. However, the complete round might have been hard to load by hand.

What did greatly reduce the effectiveness of the IJN's heavy AA was the failure to develop radar. From late 1941 or early 1942, the RN integrated radar ranges into its fire control. The USN started to do the same from late 1942 and ended with a much better system by 1944. The Luftwaffe was using its W[FONT=Times New Roman, serif]ü[/FONT]rzburg radar to direct land based AA guns in blind fire from late 1941. The US development of the proximity fuse was perhaps even more important. AFAIK, the Type 94 AA fire control on IJN ships could have accepted radar ranges and the 12.7 cm and 10 cm guns could have fired proximity fused shells. Such a system would have made attacking IJN warships in 1944 much more dangerous although it would not have changed the ultimate result.
 
The Japanese had terrible AA guns on their ships. Their 20mm and the such had a horrible rate of fire. They also didn't have any 5in that could elevate to be AAA AND reload at that elevation.
The only 20 mm AA guns likely to be found on a WW2 Japanese ship were the IJA's Type 98 guns http://en.wikipedia.org/wiki/Type_98_20_mm_AA_Machine_Cannon mounted on Army controlled merchant ships. It was an average land based 20 mm with a high velocity but a moderately low rate of fire. You are probably thinking of the IJN's type 96 25 mm gun. This had problems, partly because it was an attempt to fill what turned out to be two different roles with one gun.

The best approach to understanding WW2 automatic AA guns might be to read our own Tony Williams 's book “Rapid Fire” or look at his web site http://www.quarry.nildram.co.uk/index.htm. However, to summarise, there were two or perhaps three types of automatic AA gun mounts on WW2 warships: Power operated and generally water cooled guns such as the Bofors 40 mm, which was often used in twin or quadruple mounts; manually powered multiple mounts such as the German 20 mm C/38 Vierling; and simple hand swung single mounts such as the famous Oerlikon 20 mm. The IJN's Type 96 25 mm was deployed as singles, twins and triples. It was chosen over competition with the Oerlikon. The Oerlikon was essentially a revenge weapon that might hit an aircraft that had already dropped its bomb or torpedo. The IJN might have hoped that the Type 96 with a heavier shell and higher velocity could actually protect warships. In retrospect, they should have bought a licence for the Bofors 40 mm (note that the USN and RN also initially rejected it but eventually received it via the British Army and the Dutch). They might have also wanted a light weapon that would fit anywhere without needing power or water. For that job there was nothing special about the Oerlikon except that it was expensive and reliable as expected of a product of Switzerland. The IJN could have even used the IJA's Type 98 :D:D. Possibly the German C/38 was the best 20 mm but that was only available from 1938.

Finally a comparison between the Type 96 and the gun chosen by the USN, the 1.1” http://www.navweaps.com/Weapons/WNUS_1-1-75_mk1.htm. The Type 96 fired a 0.24 kg shell at 900 mps. The cyclic rate was 220 - 260 rounds per minute but the effective rate was only 110 - 120 rounds per minute. Single mounts weighed 785 kg, twins 1,100 kg and triples 1,800 kg. The 1.1” was heavier and was water cooled. It fired a 0.416 kg at 823 mps at a cyclic rate of 150 rounds per minute with a practical rate of about 100 rounds per minute. Quadruple mountings weighed between 4.7 and 6.25 tons. The Navy weapons site is less than flattering about both weapons. On the 1.1” it says “During early service use, it was found to be unreliable, prone to jamming and ineffective as an AA weapon”. However, the USN had the good sense and industrial strength to re-equip with the Bofors with the first mounting on a training ship in June 1942.
 

Geon

Donor
Pearl Harbor

If the attack on Peral Harbor would have worked, then the Jappanease would have had a very, very good chance of winning the Pacific War.

Dale and Don Lardo's back and forth discussions sort of crowded out any response to sportsfanatic's brief post. And since this thread has been bumped I feel comfortable responding to his earlier post.

The idea of the Japanese winning the Pacific War if they had managed to do better at Pearl Harbor, i.e. if they had been able to sink the carriers there and if they could have destroyed the fuel tanks and repair facilities with a third strike is a fallacy I'm afraid.

The Japanese entered World War II underestimating two things: the US industrial capacity and US resolve. Assuming that Japan met all of its victory conditions at Pearl Harbor (see above) it would have only delayed the U.S. victory by a few months at most.

The US Navy would have had carriers back in the Pacific within a few months to a year. While Japan could have taken more territory it would then be overextended and vulnerable to those carriers. Also remember, many of the ships reported "sunk" at Pearl Harbor were later repaired and continued to serve in the wars in the Atlantic and Pacific. A victory at Pearl might have butterflied away Midway and Coral Sea, but as Gridley pointed out in his recent masterful timeline December 28, 1941, it would have only delayed the inevitable reckoning for Japan.

Secondly,the Japanese totally underestimated the U.S. reaction to their surprise attack. The U.S. was completely and utterly furious at the Japanese for what they had done. The Pacific War matched the Eastern Front in Europe during World War II for shear ferocity. Stephen Ambrose put it best, Japan dealt the U.S. such a humiliating defeat that there was no question of anything but total victory from the U.S. point of view.

Japan might gain a few months from a total victory at Pearl Harbor but the end would be even worse for them.

Geon
 

elkarlo

Banned
The only 20 mm AA guns likely to be found on a WW2 Japanese ship were the IJA's Type 98 guns http://en.wikipedia.org/wiki/Type_98_20_mm_AA_Machine_Cannon mounted on Army controlled merchant ships. It was an average land based 20 mm with a high velocity but a moderately low rate of fire. You are probably thinking of the IJN's type 96 25 mm gun. This had problems, partly because it was an attempt to fill what turned out to be two different roles with one gun.

The best approach to understanding WW2 automatic AA guns might be to read our own Tony Williams 's book “Rapid Fire” or look at his web site http://www.quarry.nildram.co.uk/index.htm. However, to summarise, there were two or perhaps three types of automatic AA gun mounts on WW2 warships: Power operated and generally water cooled guns such as the Bofors 40 mm, which was often used in twin or quadruple mounts; manually powered multiple mounts such as the German 20 mm C/38 Vierling; and simple hand swung single mounts such as the famous Oerlikon 20 mm. The IJN's Type 96 25 mm was deployed as singles, twins and triples. It was chosen over competition with the Oerlikon. The Oerlikon was essentially a revenge weapon that might hit an aircraft that had already dropped its bomb or torpedo. The IJN might have hoped that the Type 96 with a heavier shell and higher velocity could actually protect warships. In retrospect, they should have bought a licence for the Bofors 40 mm (note that the USN and RN also initially rejected it but eventually received it via the British Army and the Dutch). They might have also wanted a light weapon that would fit anywhere without needing power or water. For that job there was nothing special about the Oerlikon except that it was expensive and reliable as expected of a product of Switzerland. The IJN could have even used the IJA's Type 98 :D:D. Possibly the German C/38 was the best 20 mm but that was only available from 1938.

Finally a comparison between the Type 96 and the gun chosen by the USN, the 1.1” http://www.navweaps.com/Weapons/WNUS_1-1-75_mk1.htm. The Type 96 fired a 0.24 kg shell at 900 mps. The cyclic rate was 220 - 260 rounds per minute but the effective rate was only 110 - 120 rounds per minute. Single mounts weighed 785 kg, twins 1,100 kg and triples 1,800 kg. The 1.1” was heavier and was water cooled. It fired a 0.416 kg at 823 mps at a cyclic rate of 150 rounds per minute with a practical rate of about 100 rounds per minute. Quadruple mountings weighed between 4.7 and 6.25 tons. The Navy weapons site is less than flattering about both weapons. On the 1.1” it says “During early service use, it was found to be unreliable, prone to jamming and ineffective as an AA weapon”. However, the USN had the good sense and industrial strength to re-equip with the Bofors with the first mounting on a training ship in June 1942.

My mistake, I meant the 25mm, which the fire rate for it was kinda bad.

I just read a book on Japanese Heavy Cruisers, and it seems as though their AA defense was pretty lacking in general. Firecontrol wasn't that great, and their weapons were just not up to snuff for WWII situations.

Will write a better response tmrw, off to bed. Sorry:(
 
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