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Old 12-22-05, 05:04 PM   #1
donut
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Default For those whom wish to play IJN.

From site http://www.combinedfleet.com/ss.htm Japan had what was easily the most diverse submarine fleet of any nation in the Second World War. These included manned torpedoes, midget submarines, medium-range submarines, purpose-built supply submarines (many for use by the Army), long-range fleet submarines (many of which carried an aircraft), submarines with high submerged speed, and submarines that could carry multiple bombers.

Because of the vastness of the Pacific, Japan built many boats of extreme range and size, many of which were capable of cruises exceeding 20,000 miles and lasting more than 100 days. In fact, Japan built what were by far the largest submarines in the world, indeed, the only submarines over 5,000 tons submerged displacement, or submarines over 400 feet in length until the advent of nuclear power. These same boats were credited with a range of 37,500 miles at 14 knots, a figure never matched by any other diesel-electric submarine. These large boats could each carry three floatplane bombers, the only submarines in history so capable. Japan built 41 submarines that could carry one or more aircraft, while the vast submarine fleets of the United States, Britain, and Germany included not one submarine so capable.

During the Second World War, there were 56 submarines larger than 3,000 tons in the entire world, and 52 of these were Japanese. Japan built 65 submarines with ranges exceeding 20,000 miles at ten knots, while the Allies had no submarine capable of this feat. By 1945, Japan had built all 39 of the world's diesel-electric submarines with more than 10,000 horsepower, and all 57 of the world's diesel-electric submarines capable of 23+ knots surface speed.

The Japanese navy also built submarines with the fastest underwater speeds of any nation's combat submarines. They employed 78 midget submarines capable of 18.5 to 19 knots submerged, and built 110 others capable of 16 knots. As the war was ending they completed four medium-sized submarines capable of 19 knots submerged. This exceeds the 17.5-knot performance of the famed German Type XXI coming into service at the same time. As early as 1938, Japan completed the experimental Submarine Number 71, capable of more than 21 knots submerged.

Japanese submarines employed the best torpedoes available during the Second World War. The Type 95 torpedo used pure oxygen to burn kerosene, instead of the compressed air and alcohol used in other nation's torpedoes. This gave them about three times the range of their Allied counterparts, and also reduced their wake, making them harder to notice and avoid. The Type 95 also had by far the largest warhead of any submarine torpedo, initially 893 pounds (405 kg), increased to 1210 pounds (550 kg) late in the war. All Japanese torpedoes made during the war used Japanese Type 97 explosive, a mixture of 60% TNT and 40% hexanitrodiphenylamine. Most importantly, the Type 95 used a simple contact exploder, and was therefore far more reliable than its American counterpart, the Mark 14, until the latter was improved in late-1943. Japan also developed and used an electric torpedo, the Type 92. This weapon had modest performance compared to the Type 95, but emitted no exhaust and, therefore, left no wake to reveal its presence. Similar electric torpedoes were used by several nations.

Given their size, range, speed, and torpedoes, Japanese submarines achieved surprisingly little. This was because they were mainly employed against warships, which were fast, maneuverable, and well-defended when compared to merchant ships. Japanese naval doctrine was built around the concept of fighting a single decisive battle, as they had done at Tsushima 40 years earlier. They thought of their submarines as scouts, whose main role was to locate, shadow, and attack Allied naval task forces. This approach gave a significant return in 1942 when they sank two fleet carriers, one cruiser, and a few destroyers and other warships, and also damaged two battleships, one fleet carrier (twice), and a cruiser. However, as Allied intelligence, technologies, methods, and numbers improved, the Japanese submarines were never again able to achieve this frequency of success. For this reason, many argue that the Japanese submarine force would have been better used against merchant ships, patrolling Allied shipping lanes instead of lurking outside naval bases. Bagnasco credits the Japanese submarine fleet with sinking 184 merchant ships of 907,000 GRT. This figure is far less than achieved by the Germans (2,840 ships of 14.3 million GRT), the Americans (1,079 ships of 4.65 million tons), and the British (493 ships of 1.52 million tons). It seems reasonable that an all-out blitz of the American west coast, the Panama Canal, and the approaches to Hawaii, New Zealand, Australia and India would have caused the Allies more difficulty than did the naval deprivations that were actually achieved. Losing a significant number of merchant ships, and also needing to spread meager defenses even more thinly along two coasts, would surely have had some substantial consequences for the United States in 1942.

The Japanese did, of course, make some attacks on merchant shipping in the Pacific and Indian Oceans, but these were the minority of missions. Frequently, they waited for fleets that were never seen, supported spectacularly brave but inconsequential reconnaissance flights, or toted midget submarines about, all of which achieved rather less than was possible with so valuable a resource as the Japanese submarine fleet. Worse from a naval perspective, Japanese submarines were increasingly employed in running supplies to the starving garrisons of isolated islands. The Japanese expended hundreds of sorties in this way, which might have otherwise been used offensively against the Allied war effort. A submarine's cargo capacity was much less than that of a relatively inexpensive freighter. However, Japan was understandably reluctant to let island garrisons starve. Additionally, many practically unarmed submarines (including 26 built for Army use) were built specifically for the supply role, consuming production resources as well.

For their disappointing achievements, Japanese submarines paid heavily. Japan started the war with 63 ocean-going submarines (i.e., not including midgets), and completed 111 during the war, for a total of 174. However, three-quarters of these (128 boats) were lost during the conflict, a proportion of loss similar that experienced by Germany's U-Boats. Most of the surviving boats were either dedicated to training roles or were recently completed and never saw combat. Of those which saw significant combat, the toll was very grim indeed. For example, of the 30 submarines that supported the Pearl Harbor attack, none survived the war.

Compared to German submarines, Japan's huge boats were relatively easy to sight visually and with radar, slow to dive, hard to maneuver underwater, easy to track on sonar, and easy to hit. Japanese hulls were also not as strong as those of German boats, and therefore could not dive as deeply nor survive such rough treatment. Also, they lacked radar until the first sets were installed in June 1944, and never had sets as good as the Allies possessed.

Compounding these deficiencies, Japan was at war with the United States and the United Kingdom, two nations embroiled in a vast conflict with hundreds of U-Boats in the Atlantic, and hence two nations which poured lavish resources into anti-submarine warfare (ASW) research and development. As an example of the fruits of this research, in June 1944 the US Navy sank the I-52 by using code-breaking to discover her schedule, finding her at night with radar-equipped carrier-based aircraft, tracking her underwater with sonobuoys dropped by those aircraft, and sinking her with acoustic homing torpedoes dropped by the same aircraft. The Japanese could achieve none of these technological feats at that time.

In the face of such disadvantages, morale declined within the Japanese submarine force. This is reflected in a post-war report prepared by the US and British Navies which states, "It was frankly impossible to believe that submarines could spend weeks on the US west coast 'without contacts,' or spend more than 40 days running among the Solomons during the Guadalcanal campaign 'without seeing any targets.' Even the Japanese commanding officers could not disguise their embarrassment when recounting these tales. Further enlightenment is found in the extremely large number of times the target was 'too far away to attack.'"

Sources:

Polmar, Norman and Dorr B. Carpenter. Submarines of the Imperial Japanese Navy, Conway Maritime Press, 1986.

Boyd, Carl and Akihiko Yoshida. The Japanese Submarine Force and World War II, Naval Institute Press, 1995.

Bagnasco, Erminio. Submarines of World War Two, Naval Institute Press, 1977.



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Old 12-24-05, 04:17 PM   #2
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a few years ago , i converted a few of the IJN subs from DC , tweaked em a bit, made em work in sh2. I find it to be a heckuva challenge.
Dual deck guns on a couple of em and the midget subs are a hoot
As long as i dont get worried about surviving regularly, its fun ...

I'm surprised with all the potential sh2/dc had in terms of VARIETY,
IJN vs dutch, us or brit; brit vs ijn german or italian ETC
that they continue to make such short sighted products instead.

mandatory "these guys vs those guys" instead of whoever vs whoever

i would prefer to see an sh4 / dc2 solely focused on multi play
with the ability to play as VARIOUS nations and submarines vessels
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Old 01-07-06, 08:29 PM   #3
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I completely agree with you.

This is the problem with conventional marketing, is it can only predict how known products sell. Something which concentrates soley on multiplay is really a new product, and nobody seems to see the potential a geared multiplayer-war-simulation like that would have.

The sad part is, especially with SH3, is the multiplay aspect is THERE, it just hasn't been tweaked in ANY WAY to take advantage of the capabilities it offers.

It's definitely a completely neglected potential.
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Old 01-07-06, 09:18 PM   #4
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Here's a painting (The Final Act -Artist: John Meeks) of the Japanese submarine I-25 capable of carrying aircraft. It provides a good aspect point to convey the huge size of the sub. Yeah, try to model one of these in the game.




"The story behind the painting...
Designed to attack the Panama Canal (an act which would have given the allies a few problems!), the I400 class boats of the Imperial Japanese Navy were the largest submarines of WWII - and never saw combat ! Of this class, only two or three appear to have survived until the end of the war. I404 was destroyed in a bombing raid, and I405 was never completed.

Monstrous vessels (with a submerged displacement in the order of 6000 tons, a crew of apparently 180-odd men, and...well, that hangar could take a London or New York subway train...!) they were true submersible aircraft carriers, each being equipped with three Aichi M6A1 "Seiran" floatplane attack bombers. "

http://www.subart.net/final_act.htm
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Old 01-07-06, 09:44 PM   #5
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That's insane. I didn't know anything about them.

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Old 01-07-06, 09:58 PM   #6
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They were both on their way to attack the U.S. carrier anchorage at Ulithi atoll just as the war ended. Fascinating as these monster subs were they are also very symbolic of how Japan frittered away her rather meager resources during the war. Even if they had managed to damage the Panama Canal locks at that point in the war it probably wouldn't have made much of a difference
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Old 01-09-06, 03:02 PM   #7
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Quote:
Originally Posted by ironkross
Here's a painting (The Final Act -Artist: John Meeks) of the Japanese submarine I-25 capable of carrying aircraft. It provides a good aspect point to convey the huge size of the sub. Yeah, try to model one of these in the game.




"The story behind the painting...
Designed to attack the Panama Canal (an act which would have given the allies a few problems!), the I400 class boats of the Imperial Japanese Navy were the largest submarines of WWII - and never saw combat ! Of this class, only two or three appear to have survived until the end of the war. I404 was destroyed in a bombing raid, and I405 was never completed.

Monstrous vessels (with a submerged displacement in the order of 6000 tons, a crew of apparently 180-odd men, and...well, that hangar could take a London or New York subway train...!) they were true submersible aircraft carriers, each being equipped with three Aichi M6A1 "Seiran" floatplane attack bombers. "

http://www.subart.net/final_act.htm
THAT IS NOT MY NAMESAKE!

thats clearly the I-400 the I-25 was a Single plane sub

aahh... i wanted to be the first to put this post up...
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Old 01-10-06, 04:15 PM   #8
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Ive occasionally used the NSSB2 in sh2 with an
airbase attached to it to have the scout plane.

really helps as one cant hear much at 23.5 kts
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Old 01-13-06, 12:10 AM   #9
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Hey guys do you know what words says?

It says 最期の幕 "saigo no maku"
That's mean Last chappter or Act on death
,end roll.

I don't know why this paiting say so.


This is now what I now maiking,1/700 scale
I-400, Ro-35, U type 7



How huge I-400 is!!!
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Old 01-14-06, 11:22 AM   #10
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Quote:
Originally Posted by I-25

THAT IS NOT MY NAMESAKE!

thats clearly the I-400 the I-25 was a Single plane sub

aahh... i wanted to be the first to put this post up...
Thanks for the correction. I'm ignorant of much of the IJN sub types. Just got that off a website.
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Old 01-17-06, 02:41 PM   #11
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I was investigating the Imperial Japanese Navy, and I found out that these guys were very serious

Take a look at the hardware:











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Old 01-17-06, 06:49 PM   #12
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Quote:
Originally Posted by zaza


How huge I-400 is!!!
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Old 01-17-06, 09:03 PM   #13
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Quote:
Originally Posted by VON_CAPO
I was investigating the Imperial Japanese Navy, and I found out that these guys were very serious

Take a look at the hardware:
Well...of course they were serious. When you consider what a large and well-trained carrier force the Japanese had the IJN was arguably the most powerful fleet in the world in 1941. Especially after Pearl Harbor and the sinking of Force Z off Malaysia. Plus, they only had to concentrate their efforts on dominating one ocean.

It was trying to replace this hardware with their slender industrial base as the war wore on that eventually did them in. They simply couldn't afford to just trade losses ship-to-ship with the Allies. The "Decisive Battle" that would decide the war in one stroke in their favor kept eluding them. That and the lack of a pilot program to produce enough well-trained naval aviators to make up for the heavy attrition at Coral Sea, Midway and all the other carrier battles was ultimately the undoing of the Imperial Japanese Navy.
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Old 01-17-06, 11:31 PM   #14
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Quote:
Originally Posted by Torplexed
It was trying to replace this hardware with their slender industrial base as the war wore on that eventually did them in. They simply couldn't afford to just trade losses ship-to-ship with the Allies. The "Decisive Battle" that would decide the war in one stroke in their favor kept eluding them. That and the lack of a pilot program to produce enough well-trained naval aviators to make up for the heavy attrition at Coral Sea, Midway and all the other carrier battles was ultimately the undoing of the Imperial Japanese Navy.
Excellent analysis.
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Old 01-18-06, 04:00 AM   #15
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Yeah....but you always wonder. If they hadn't blown it at Midway. If they had used their submarines more often for commerce-raiding. Had they rotated veteran pilots from front-line duty to train recruits. If somebody had fired Nagumo early on might things be different? Probably not much different...but it is fun to speculate.
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