Imperial Japanese Equipment

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The Empire of Japan: the first East Asian country to successfully industrialize in the late 19th century and from the 1930s to 45 the scourge of the Pacific. The second most powerful Axis nation and had their own theatre. While better off than Italy (which isn't saying much...), Japan still lagged behind in a lot of fields and had major raw materials and fuel shortages.

Generally speaking Imperial Japanese gear generally falls into four categories...

• Solid by Great War and Inter-War standards but out of date for WWII.
• Good, if made with some weird logic or specific bit of Min-Maxing in mind.
• Unusable/near unusable garbage due to cost cutting and bizarre moon logic.
• Really rough and dirty stuff cludged together as Japan got a major beat down.

Small Arms

Japan's small arms were generally less advanced than that of other countries at the time; while most countries still relied on bolt-action rifles as their service weapon, many countries still produced decent quantities of SMGs as well as self-loading rifles in more limited numbers. Japan however focused primarily on bolt-action rifles, with fewer automatic weapons to back them up. Weapon quality also suffered later in the war as well.

Rifles and SMGs

The Arisaka rifle, not to be confused with rifles made by Arasaka

• Type 30 Arisaka: Japan's old rifle, designed by Arisaka Nariakira and put into service in 1899, it saw use in the Russo-Japanese War and the Great War. Fired a 6.5x50mm bullet. Generally a solid five-shot bolt action for it's day, if a bit underpowered.
  • As a side note, the 6.5x50mm Arisaka bullet was better suited for a man-portable automatic weapon than the typical over-charged full rifle rounds of the late 19th/early 20th century, which were made with accuracy and stopping power in mind. The Russian Fedorov Avtomat used them.
• Type 38 Arisaka: Update on the Type-30. Used primarily in WWI, and partially replaced by the Type 99 in WWII. Had utterly shit sights and a weird safety.
• Type 97 Arisaka: Type 38 rifle adapted for sniper use, usually with a 2.5x power scope. 6.5x50mm produces very little flash and smoke when coming out of a long barrel, making Japanese snipers difficult to spot.
• Type 99 Arisaka: Built to replace the Type 30 and Type 38 by firing a 7.7x58mm cartridge. Improvements to the sights also made it the preferred rifle for snipers. That said, the Japanese still had a lot of Type 38s and 6.5x50mm, so it never fully replaced the Type 38. The sniper variant of the Type 99 was one of the more sensible snipers of the war, as the scope was mounted offset so that strip mags could still be inserted, resulting in a faster overall rate of fire. Also had a terrible trigger and the same shit sights from the Type 38.
• Type 4 Rifle: It became apparent to the Japanese that many countries were now adopting semi-auto rifles, including the German G43, the Russian SVT40, but especially the American M1 Garand. Since they didn't have the time or resources to develop a brand-new rifle during the war, they basically reverse-engineered the Garand and built it to use the same 7.7mm stripper clips as the Type 99. A few hundred were made but were never deployed before the war ended.
• Pedersen Rifle: This semi-automatic rifle had competed with the M1 Garand for adoption in the US Military; when it failed trials, a number had been sold to the Japanese government before the war. This gun uses the same toggle-action used on the luger pistol, making it more prone to mechanical failure. While the Japanese didn't have many of these rifles, they were used in the Battle of Okinawa. An attempt at copying it, the Type Ko, never left the prototype stage.
• SIG Bergmann Model 1920: A common export SMG made under license that copied the Bergmann MP18, this updated version replaced the side-loading Luger snaildrum magazine with a straight magazine. The Japanese purchased the version in 7.63x25mm Mauser and used it as their primary SMG for the Sino-Japanese war.
• Type 100 Nambu: The only production SMG made by the Japanese, and made in more limited numbers compared to other militaries. The Nambu SMG fired the same 8x22mm cartridge as the standard Nambu pistol. It had sideloading magazine much like the earlier MP18 and contemporary Sten; while side-loading magazines had fallen out of favor by this time due to the unbalanced weight, it was a hell of lot better than the other experimental Nambu SMGs that had been made at the time.
• Nambu Experimental Model 2: One of the experimental SMGs developed before the war; it was initially rejected, but the urgency for more SMGs pushed the design into production. However, because it was being produced in Manchuria, the Chinese Communists took the design and used it during the Chinese Civil War, these being converted to use .45 ACP Thompson magazines.
• Murata Rifle: The OG of Japanese military rifles, first put into production back in 1880 and used during the Russo-Japanese war. Originally single shot, latter got a tube-mag upgrade. Only used on the home islands for the civilian reservists.
• Last Ditch Guns: In the late war, Japanese manufacturing had been effectively crippled and resources were in short supply, so these so-called "Last Ditch Rifles" were made to arm what military forces remained, as well as civilians for the upcoming invasion of the Japanese home islands. These ranged from simplified versions of the Type 99 to very crude single-shot musket-things to give to civvies. Most of the stereotypical garbage that would explode at the slightest touch issues occurred here. While they didn't issue guns that would actually explode (that dishonor would go to the poor abused things Kijiro Nambu's pistols were reduced to by the late war) much more than normal, quality control rapidly went down the drain and reliability issues really did go up a lot. Most likely they jest wouldn't fire or get jammed far earlier than early war guns.

Pistols

• Type 26 Revolver: A simple break-action hammerless revolver, chambered in 9mm Japanese revolver. Was invented back in 1893 but was still used in WWII to supplement weapon stockpiles.
• Nambu Type 14: The standard sidearm of the IJA following WWI, replacing the Type 26. Chambered in 8x22mm, it wasn't as strong as contemporary pistols, but was solidly built, and later became the inspiration for the Ruger .22 pistol. A common misconception is that the Type 14 was dangerous to shoot, which is only half true. It won't explode, but it will sometimes go off when clearing a jam(more on that below). Another is that the Nambu was a cheaper knockoff of the Luger, which is untrue. The Type 14 is a series of improvements of an earlier weapon commonly called "Grandpa Nambu", a firearm which appeared in production at roughly a similar time to the Luger. While not objectively terrible, it was nothing compared to the Italian Berreta or Browning's 1911. It frequently jammed as well due to the springs not being able to keep up with the bolt, and was compounded by the bullets being angled up. The magazine release is also difficult to clear without adjusting your grip. However to the weapon's credit it had a very light trigger pull and had a trigger guard designed to allow troops wearing gloves to use them without removing said gloves.
• Nambu Type 94: A smaller, lighter-weight pistol compared to the Type 14. It was called the "Surrender Pistol" because it had an exposed sear, meaning that pressing down on the sear could fire the gun without pulling the trigger, so supposedly a Japanese soldier could fake surrendering so that they could shoot their captors up close. While this may have happened on occasion, stories of surrendering troops regularly firing using the sear are probably unsubstantiated, as it takes a considerable amount of force to squeeze the sear hard enough to fire the pistol. The Type 94 was used primarily by officers, army airmen, tankers, and paratroopers due to the lighter weight. If the safety was not on, the exposed seer could lead to accidental discharge if it was bashed into something and occasionally they blew up in people's hands when fired.
• Hamada Type Pistol: a Browning-style pistol that was developed after Japan could no longer import foreign pistols. While cheaper and more reliable than the Nambu pistol, it arrived late into the war. The Type 1 was chambered in .32 ACP, and the Type 2 was chambered in 8x22mm.

Machine Guns

The lengths some people will go for cross-compatibility

• Type 11 Light Machine gun: Put into service in 1922, this gun is weird. It's like the gun equivalent of putting a USB port on an iPhone so you can use the same flash drive in it and your laptop. Basic idea, make a machine gun that could use the 5 round stripper clips used by Arisaka Rifles. That means you don't have to make special magazines for it or ship them to the front, while regular infantry dudes can supply it with bullets in a pinch. So it has this weird hopper magazine that takes up to 6 clips. This also meant putting the stock off to the side for balance. While it worked, it was heavy, awkward and not terribly reliable, especially in the dirty jungles where the open hopper was vulnerable to dirt getting in. The Soviets captured a few and actually made a few prototypes with a copied mechanism before realizing that it was more hassle than it was worth.
• Type 96 Light Machinegun: to address the problems with the Type 11, the Japanese replaced it with a different model that used a top-loading magazine, based on the Czech ZB VZ 26 (which also inspired the Bren Gun).
• Type 97 Light Machine Gun: Another machinegun based on the VZ 26, but more heavily built as it was intended for mounting on tanks. Rarely deployed as an infantry machinegun due to the extra weight, it featured an integrated scope and heavy barrel jacket to give it a distinctive appearance.
• Type 99 Light Machine Gun: Visually similar to the Type 96 but chambered in the same 7.7x58mm ammo as the Type 99 Arisaka. Other than that, it and the Type 96 were one of the few LMGs with a bayonet mount.
• Type 3 Heavy Machinegun: Static machinegun mounted on a tripod. Based loosely on the Hotchkiss machinegun in that its barrel has large cooling rings and feeds from 30 round feed strips. Chambered in 6.5mm. Just like the original Hotchkiss gun, the feed strips may be faster to load than an ammo belt and are reuseable, but any dirt or warping in the strips makes them unusable.
• Type 92 Heavy Machinegun: overall shares the same layout as the Type 3, but chambered in 7.7mm.

Anti-Tank Infantry Weapons

• Type 4 70 mm AT rocket launcher: Introduced in 1944 as an answer to the American Bazooka. Fairly basic but still a reusable item, a rocket was slotted into the front and set up by a simple percussion lock. A few thousand of these were made before the war ended and they saw only limited use. Never the less the PLA copied them for their first generation of RPGs.
• Lunge Mine: Somehow the Japanese figured out a way to banzai charge tanks of all things. Little more than a shape charge attached to a pole, the idea was that a soldier would wait in ambush for an enemy tank to get close enough; the attacker would then charge at the tank’s side armor and strike it with the lunge mine to set it off; of course, at that range the explosion would more than likely kill or maim the user, if they weren’t already killed from trying to charge a friggin tank.
• Type 97 Automatic Cannon: The Japanese version of the AT-rifle concept. Hilarious because they considered it a cannon and less of an AT-Rifle. Shot 20mm ammo. So did the Finnish AT-rifles, but it is more hilarious because Japan also built Yamato(more on that below). What was unique is that they ended up getting used on some Japanese aircraft as a form of cannon. Overall not a terrible weapon, but quickly became outdated and was abandoned after 1200 total units due to the sheer complexity, but it certainly puts a massive dent in the "Japan just built shitty stuff" myth.

Misc

• Type 89 and Type 10 Grenade dischargers, aka "Knee Mortars": A nifty little Japanese design, these are basically miniature man-portable mortars. Lightweight (around 5 kg) and nominally requiring only a single soldier to use , they were capable of chucking a hand grenade up to 200 meters away, which came in pretty handy in the often close and cramped firefights in the jungle. As an amusing sidenote, the name 'Knee Mortar' comes from a mistranslation of a Japanese manual on how to use the thing: American soldiers first believed they were supposed to be braced against one's leg due to the curved butt-plate (which in reality is to make it easier to rest against tree roots or rough ground). While the error was quickly discovered (it was obvious from the recoil that bracing it on your leg would break your femur at best), the name stuck.
• Guntō: Bargain Basement knock-off katanas. It was a regulation that all IJA officers were required to carry a sword and to that end a large number of these swords were made. Since Japan was raising a fuck-huge army under the militarists, they dispensed with the old arts of Sword Production and instead produced lots of blades quickly with modern milling/grinding/quenching techniques. For this reason, such 'modern' blades aren't considered traditional swords in Japan and they can be confiscated by the government for recycling. Real traditional katanas were a very rare sight on the battlefields of WWII, for even those officers that came from an old samurai family and possessed a genuine one often left the priceless family heirloom at home and carried a fancied-up Guntō (that would do the job in a pinch anyway) in battle. A lot of the surviving ones today are trophies collected by US Army soldiers and Marines (and often misidentified for genuine katanas by the uninformed).
• Bayonets: The IJA stuck bayonets on everything. Not just rifles, but also their LMGs and SMGs. Bayonet charge had fallen out of favor with everyone else, and bayonets were only a last ditch weapon for everyone else, but bayonet fighting was still a mainstay of the IJA and had some success on the Chinese front. Against the Americans, however, who possessed significantly more automatic weapons and Garands, it had been rendered a useless tactic. They did gain some amount of utility when used in conjunction with night attacks, but as the war went on the number of seasoned troops who could pull this off had been drowned, killed in dumbass final charges to redeem their honor, or killed in any other ways the Pacific and Asia had to offer, including but not limited to Malaria, Malnutrition, Naval bombardment, Aerial Bombardment, Flamethrowers, Flamethrowers in Tanks, Indian Crocodiles, Angry Gurkhas and even Angrier Aussies.

Vehicles

Tanks

The Tank Fleet of the Imperial Japanese Army was not that great. Our dear friends had experimented with the tank concept pretty early on; they were the first nation to make a tank with a diesel engine, but much like the rest of the world took the wrong lessons from Spain. They also failed to integrate the weapons into divisions properly. The skirmishes with the Soviet Union and visits to Germany in the late 30s pretty much proved that the concept worked different than they thought, and they tried to catch up. However, tanks take a lot of money, labour and equipment to produce and a lot of fuel to operate, and the thing you need to know about the Empire of Japan is that above all else, the army and the navy literally without question hated each other. So every time the Army wanted to start production of tanks they had to compete for steel, manpower, labour, and everything else. Given that in China 1930s era tanks were still quite effective and if war happened with the United States the fleet and air forces obviously took priority, the navy generally won these fights. So most of the "good" tanks ended up in the homeland because of the logistics strain, and the far cheaper Type 95 Ha-go/Kyugo were far more common by virtue of being lighter and thus less of a bother to send to shitty undeveloped island #273.

Imperial Japanese Tanks were given a designation based on the Imperial Japanese Calendar, which starts counting at 660 BCE.

• Type 95 Ha-go/Kyugo: Named Ha-go after the manufacturer but called the Kyugo by troops, either name is correct, but Ha-go is more familiar to western audiences. Japan had looked into the land battleship concept, but decided to make a tank that could both be speedy and provide infantry support. The 95 were vastly faster than equivalent infantry support tanks like Matildas or Churchills. They even were cheaper to make, and were cushioned against heat and bumps...by asbestos. In Burma, one was captured and is still at Bovington, and a contemporary report indicated that there were design elements that were quite good, especially the bogie wheel suspension. However, the cannon became rapidly outdated, and the machine guns were only ok, being fed by hoppers and not belts, and the commander was cramped and somewhat overwhelmed. Perhaps worst of all was that crews were strongly frowned upon for adding on armor or boxes for ammo, though logs to allow troops to sit on the back were considered acceptable. The turret could also could be jammed with a knife, and there are allegations that American .30-06 ammo was able to penetrate the side armor, though these reports are not fully substantiated.
• Type 2 Ka-Mi: One of the world's first true Amphibious tanks that originated out of the Army-Navy rivalry. The IJN wanted their light infantry to have some Amphibious tanks, so they modified a Type 95 chassis to have releasable pontoons and even a propeller. Were hand crafted, so production was far slower than the Navy wanted. Interesting, but woefully outdated once American LVTs arrived. Mostly saw defensive action as mobile pillboxes and defensive emplacements at IJN installations.
• Type 97 Chi-Ha: The main medium tank of the IJA during WWII. It weighed 14.3 tonnes, a 127kW engine, armor 8-26mm thick and was armed with a 57 mm main gun and a couple of machine guns. When it was introduced in 1936 the Chi-Ha was pretty good and it was often effective in China. When the US came around, not so much. A command variant, the Shi-Ki, mounted the cannon in the hull to make room for the officer's radio.
  • Type 97 ShinHōtō Chi-Ha: A Chi-Ha with more armor and a higher velocity 47mm gun better for anti-tank work introduced in 1942.
• Type 1 Chi-He: Another upgrade on the Chi-Ha with some more armor and a better engine. About 170 were made and they stayed on the Home Islands.
• Type 3 Chi-Nu: Another upgrade on the Chi-Ha, with up to 50mm of armor and a 75mm anti-tank gun. It was designed to take out Shermans in 1943 and put into production in 1944 when Japan was getting a serious ass whoopin by US Bombers. The most advance Japanese Tank to see even limited mass production. Stayed in the Home Islands.
• Type 4 Chi-To: Not an update on the Chi-Ha, but an entirely new vehicle from the ground up. A couple of Prototype vehicles which were broadly speaking in the T-34/Sherman's ballpark. The Cheeto's legacy is mostly preserved by World of Tanks and Alternate History nerds.
• Type 5 Chi-Ri: A single prototype that, had it been completed would have been more heavily armored than a Sherman with a new powerful 75mm gun, plus a 37mm secondary cannon. If the M6's trials are any indication the 37mm would've been superfluous, though it isn't like Japan had access to Aberdeen proving grounds or anything so how would they have known?

Tank Destroyers/Assault Guns

Similarly to the whole tank thing, Japanese Tank Destroyers and Assault guns suffered from the Navy and Army thing. When they did finally start producing them, they were rushed, too late to make a difference, relatively poor in quality, and facing off against an incredibly pissed off enemy that had goddamn howitzers mounted in tank turrets.

• Type 4 Ho-Ro: Based off the Type 97 chassis and studies of the German Grille. Mounted a respectable 105mm cannon in an open topped casemate design. Few (12) were produced, with the ones that were facing off against the M7 Priest, M1, and M101. So yeah, they were having a fun day every time they were deployed.

• Type 97 Chi-Ha, 120mm cannon: Based again off the Type 97 chassis. The Short Barrel variant has the "most" documentation, being just a Chi-Ha with a 120mm goddamn anti-submarine cannon mounted to it. Fitted to fire HE shells, it was able to fire AP shells as well. Primarily used in the infantry support role. A variant appears in War Thunder called the Type 97 Long Barreled, fitted with a long barreled 120mm cannon that left the crew exposed to fire, though documentation is even rarer and thus it is unknown how prolific the latter of these truly were.

Halftracks and armored cars

Much like the rest of the powers involved in the second world war, the Imperial Japanese Army did have a pool of halftracks and armored cars. Uniquely among most powers, most of the Japanese armored cars had a rather unique feature; they could be deployed on both roadways and rail lines. This is similar to modern railway utility trucks, except they arent armored or armed.

The Imperial Japanese Army, while stereotyped for having terrible equipment, did at least have some innovation through their armored cars in that the wheels that allowed them to be used on railways could be switched to different rail gauges and did develop one of the first ancestors to modern fully tracked armored personnel carriers.

A major fail was that the IJA did not prioritize infantry transports as much as other more mechanized militaries did and as a result they where outclassed by allied forces and superior designs.

Some of the more famous examples of armored cars and half tracks most of which were based on 1920s interwar British designs.

• Chiyoda armoured car/ Type 2592: Offically the first domestically made armored car that was produced for both the IJA and the IJN, was armed with 3 Type 11 6.5mm machine guns. Only truly notable feature is it was a six wheeled design, a distinction that was shared with the American M8 and Soviet BA series of armored cars.

• Sumida M.2593: Made a year after the Chiyoda, this was the first armored car in the IJA and IJN, that could be used on both roadways and railways. The crew could change between the two in little less than half an hour, and the wheels for rail use could even be adjusted for different railway gauges. Another unique feature to this armored car was while it was used on railways it could be linked with others to form a type of rolling stock. They could be armed with either a 6.5mm machine gun or a 7.7mm machine gun with gun slits cut into the armor for its crew to use infantry weapons. Unique, but irrelevant when the Allies started deploying Greyhounds and Daimlers.

• Type 1 Ho-Ha: One of the only true halftracks produced for use by the IJA, developed in 1941, but did not reach production until 1944, it was partially based on the Germans Sd.Kfz. 251 with some American M3 influence as well. It carried 3 type 97 machine gun in constricted fire arcs leaving it exposed to attacks from the direct front and direct rear.

• Type 1 Ho-Ki: An honest ancestor of the fully tracked APC, and an example of too little too late for the imperial japanese military. Developed in 1941 but only began mass production in 1944, it was made originally as a heavily armored artillery tractor that was adapted to carry up to 13 infantry. It was unarmed but provisions were made to mount a type 92 infantry machine gun.

Ships

Of all the Axis powers, the Empire of Japan had the strongest navy. Germany had to rebuild its fleet effectively from scratch and Italy... was Italy. Japan, on the other hand, was THE major ally of Great Britain in East Asia after World War 1 and was "permitted" to expand its fleet up to two-thirds the tonnage of Great Britain and the United States through the 1920s and '30s. As might be expected, the Japanese resented the tonnage restrictions and basically tried to circumvent or design their way around them until they eventually repudiated the naval treaties entirely. What they never really understood was that the naval treaties tied one hand behind the backs of their naval rivals, as both Great Britain and obviously the United States were able to outproduce Japan's shipbuilding industry pretty handily in World War II. The Japanese Navy was extremely effective through 1943, and it was really only after devastating losses at the Battle of Midway, where 2/3rds of their primary carrier fleet were sunk (which they didn't tell the army about for a while), that they began their decline. Good luck trying to look up a Japanese ship name without being bombarded by pictures of anime girls though.

Aircraft Carriers

Japan entered World War II with the most experienced sea aviation force in the world, with a total of 8 carriers constructed before 1940. They soon learned the lessons America and Britain eventually did, that larger carriers are better and that superimposed decks (multiple flight decks stacked like cake tiers) are a bad idea. However, they failed to anticipate the scale of their losses and were unable to complete replacement carrier construction for much of the war. One achievement that highlights this failure was the construction of the carrier Shinano, a converted Yamato-class battleship and thus the largest aircraft carrier built during the war. Because she was a conversion of a half-finished battleship hull that had been hastily chosen after the disaster of Midway, the IJN couldn't actually convert her to a full fleet carrier and settled for making one of their most expensive assets (in terms of time, money, and resources invested) into a support carrier that would focus on repairing and resupplying the air arms of full fleet carriers that, by the time she was launched in 1944, had all been annihilated. She was sunk less than two months after being launched by an American submarine, and had only ever carried 50 Ohka flying bombs.

• Akagi: An Amagi-class battlecruiser hull converted to an aircraft carrier after Japan entered into the 1922 Washington Naval Treaty. Akagi was completed with three flight decks, from which planes could theoretically be launched simultaneously. In practice, the bottom and top decks worked well while the middle flight deck was less than 1/10th the length of the top flight deck and was flanked by two twin 8" gun turrets that prevented the deck's use in battle. The lowest flight deck was also small, being only 1/3rd the length of the uppermost flight deck; both the middle and lower decks, as a result, could only be used for small, light, and increasingly obsolete aircraft. The remaining armament consisted of six casemate 8" guns, as well as six 4.7" guns for anti-ship and anti-aircraft duty. Much like the USS Langley, this early and pioneering design lacked an island for command and control arrangements. Eventually the ship was completely refit to the iconic aircraft carrier design recognized today: all major gun turrets were removed, the top flight deck was extended, and the lower decks were eliminated in favor of increased hanger space for more aircraft. An island bridge allowed for better aircraft coordination and fire control, especially for the new 25mm autocannons that were fitted to the ship. These improvements did have a negative effect on her speed, though she could now theoretically launch 80 aircraft, most of which would be A6M Zeroes.
  • Akagi carried a weakness common to most early aircraft carriers: Usually made from converted warships built for entirely different purposes, they possessed the armor specifications of a battleship against direct and indirect gunfire, but none against air attack. Their decks were especially vulnerable to enemy aerial attacks, with the American Lexington-class carriers also sharing this characteristic. Akagi was sunk by aerial divebombs during the Battle of Midway in 1942, partly because tired ordnance crews left explosives strewn throughout the open hangar and most of her planes were being pumped full of aviation fuel in preparation for a strike against the American carriers.
• Sōryū:
• Kaga: Kaga was planned to be the second of the Tosa-class battleships, but after the Washington Naval Treaty she was intended to be scrapped before being completed. Akagi's sister Amagi was wrecked while under construction in the Great Kanto Eartquake, so Kaga was converted instead.
• Shokaku and Zuikaku
• Hiyō and Jun'yō
• Taihō: An object lesson in damage control.
• Unryū, Amagi and Katsuragi (+ whole host of cancelled ships in this class):
• Shinano:

Battleships

Japanese Battleships are an interesting lot. Unlike the funny spider people or the Pizzas, the IJN actually had a decent number of Battleships that got to participate in the war. They were also rather impressive on a technological level, being well armed and well built. This is all moot though, because by the time of their arrival, it was the twilight of the Battleship era and the beginning of the Carrier era.

• Yamato class: The single largest series of battleships ever built at 263 meters, and the wet dream of any naval enthusiast, weeaboo, and big gun fan everywhere. But before we get excited, we need to make it clear that no, the Yamato was objectively the wrong ship in the wrong war. The age of the battleship, with rare exception for shore bombardment, was pretty much over. Worse of all Japan was somewhat aware of this, with foremost officers like Yamamoto outright saying Naval airpower is the future, and was proven largely correct as the only engagement Yamato or Musashi (Shinano was another ship of the line that was converted partway through construction, see her section in the carriers) ever participated in where they actually got to fire their weapons at anyone turned out to be Leyte gulf in 1944, and both were sunk by angry American dive and torpedo bombers by 1945.
  • With that boring disclaimer out of the way, let's get to the meat and potatoes. The thing had nine 480mm cannons and was housed in a turret that weighed as much as a small destroyer. On top of that, each turret could fire AA shells that would explode after a time fuse delay, and the few test photographs we have show they were a sight to behold, though US pilots reported not being too afraid of them, and they tended to damage the barrels. The class had an incredible number of medium and light weapons that could be brought to bear against lighter targets and fighters as well, with as many as 100 of these lighter weapons, though the 25mm autocannons were reportedly some of the worst in the war. There were some additional 13mm machine guns thrown on the bridge for good measure, but this was more like a desperate afterthought than a concerted effort to add additional AA protection. Still, a Yamato could still cause a small Titan or knight to sweat a little, because those main armaments are utterly insane.
  • Yamato had a ludicrous 410-650mm armor in some places, making her an armored behemoth. However, it is important to remember that Japanese steel historically sucks. The torpedo defense system was hoped to protect the ships, but was often troublesome and thus never really as effective as hoped. A prime example of this is when an American submarine hit Yamato and forced her to return to port for repairs, and the outright sinking of the Shinano by the USS Archerfish, a Yamato modified to be a "carrier support vessel". Don't forget that US Torpedoes were shit. It was more often a surprise when the Mark 48 actually did damage instead of just harmlessly bouncing off the hull of the ship.

• Kii Class: Four fast battleships planned for the eight-eight battlefleet program intended to succeed the Tosa class, cancelled after the Washington Naval Treaty, along with planned successor Number 13 class.

• Tosa Class: Essentially a better post World War 1 version of the Nagato with an extra turret, cancelled with the Washington Naval Treaty. Tosa's hull was used to test armor against ordnance and was scuttled, while Kaga was converted into an aircraft carrier after battlecruiser Amagi's hull that was planned to be converted originally was wrecked in the Great Kanto earthquake.

• Nagato class: The Nagatos were two dreadnought class vessels that served as the heaviest warships in the IJN until the arrival of the Yamatos. They came as a result of the Russo-Japanese War, and were part of a massive armament effort in light of the development of the HMS Dreadnought. The class was armed with four twin 41cm turrets and twenty casemate 5" cannons for dealing with lighter vessels and four 3" guns. They copied American belt armor designs that allowed for additional speed that made them fast for the time. Modernization added new mgs and 25mm cannons, as well as bulges for anti-torpedo duties and equipment replacement. However the class saw relatively little service throughout the war.
  • Nagato's sister ship Mutsu saw little service and coincidentally blew up and sank in harbor. The Government covered up the details so little is known to this day, but the best guess we have is that a fire got out of control and the ammo rolled a one on it's existence save. As a side-note, Mutsu was slated to be scrapped per the Washington Treaty, but internal political considerations (made a show of it being partially funded by schoolchildren' donations) made that unacceptable for Japan, so they conceded for US and UK to get extra battleships of their own to keep the ratio on.
  • Nagato herself saw very little service as well, despite being the flagship of the Pearl Harbor attacks. She fought the Americans in a few battles, but was bombed and forced to return to Japan. She then stayed in harbor as a AA gun as there wasn't enough material to get her into fighting condition again. After the war the Americans captured her and tested nukes on her, before ultimately letting her capsize. If nothing else, Nagato gets credit where it is due: The thing lasted longer than the Yamato and actually survived to be captured by the Americans, rather than being sunk by a squillion angry pilots still pissed off about the boats that they blew up. . .And America then promptly blew it up twice with Atomic Bombs in the Operation Crossroad tests. Amusingly its radiation has faded enough to seemingly become a popular diving site.

• Kongo class: The Kongo class is well known among naval combat nerds for being the ones that actually showed up and did the fighting, unlike the Yamatos. Construction of the IJN Kongo took place in Britain, but the remainder of these ships were built in Japan. Initially the primary armament was was eight 14" guns mounted in twin turrets, sixteen casemate 6" guns, as well as a token armament of four 3" guns. In addition the ship had eight torpedo tubes (four per side). The side armor was comparatively thin to the bridge, which had a whopping 355mm of armor compared to the rest of the ship having 203mm maximum belt armor. The Kongo class served quietly in WWI and were forced into training roles to conform with the Washington Naval treaty. A series of innovations during the interwar period included aircraft launchers, additional armor, a new propulsion system, and improvements and upgrades to the main and secondary armaments. This also included the installation of modern hardware like radio systems, searchlights, and fire control systems.
  • The Kongos served well and escorted convoys and aircraft carriers during the early conflict. A recurring problem for the class was once an enemy got close, all that armor didn't seem to do any good when the Americans started firing point blank into them. Half the class was sunk in engagements with other enemy ships at Guadalcanal, performing well during combat. Kongo would survive Leyte gulf until being unceremoniously demolished by American submarine USS Sealion. The last vessel of the class to fall, the Shinano, was sunk in 1945 by carrier aircraft while in harbor in Kure. Ironic that holdovers from WWI served with more distinction and service than the supposed mightiest battleships ever built.
  • There is some debate as to if the Kongos were "fast battleships" or "battlecruisers". While there is evidence to suggest the latter, they were classified as such in the IJN so that is why they are here. But for all intents and purposes they were closer to battlecruisers than true battleships.

Cruisers

The cruisers of the IJN were heavily influenced by the Battle of Port Arthur, with a preference for torpedo armed cruisers. Even within the IJN this policy was not without its detractors due to the risks of torpedo tactics. In practice, these torpedoes rarely contributed and were a frequent liability, with several cruisers being taken out of action due to their torpedoes being hit. Otherwise, Japan's cruiser force was generally well built but lacked modern fire control.

• Amagi Class: A battlecruiser class designed to capitalize on the new naval wartime technologies that emerged with the introduction of Dreadnought class warships and other post-WWI innovations. The intended armament was to be 5 twin 400mm cannons as the primary armaments, 16 5.5" casemate cannons, six 4.6" flak cannons, and 8 24" torpedo tubes. The armor was reduced to increase speed, and the overall purpose was to use them as cost effective battleships in support of Destroyer swarms. We will never really know how they performed, though two of the class were slated to be converted into Aircraft carriers, though only one would ever be completed as an aircraft carrier, the above mentioned Akagi, the Amagi's hull was severely damaged in the Great Kanto Earthquake and it had to be scrapped before completion.

Destroyers

Japanese destroyer construction after the Washington Naval Treaty emphasized fleet destroyers as a way to bulk out their navy while appearing to conform to the treaty. A series of classes were developed in the 20's and 30's but all were produced in small batches of no more than a couple dozen each. The IJN never settled on a common design for mass production like the USN did with the Fletcher. Throughout the 30's they had the A design, which was for general fleet support, the B design which was for carrier escort and AA, and the C class which would support battlefleets with torpedoes and cannons.

• Fubuki: A class of Destroyers were developed as a direct response to the Washington Naval treaty. They earned the Fubuki nickname long after they had been built. In short, they were designed to bring heavy dakka to the furthest possible distance as quickly as possible, with the heaviest armor they could get away with. They carried a whopping nine 24" torpedoes as well as some 5" cannons and some mgs, with the 5" cannons acting as AA guns as well as anti-ship weapons. 24 were built throughout the class, with only two surviving the war.
  • The Type II subclass were generally considered decent for their armament, but the Type III subclass had better power efficiency. The first ten ships were the Type I class and were particularly bad, though later ships improved on these flaws. Overall the Type III was preferred and many of the improvements found on them were given to the Type II class of ships.
  • The Fubukis suffered from being too light in weight and AA armament: the entire class had to have rebuilds to make them better at sea performance, and later in the war those lack of AA weapons bit them in the ass hard: it became so desperate that the rear primary turret was replaced with 25mm aa guns. However, they still served well in spite of these flaws, and was the class of ship responsible for stranding JFK at sea.
• Shimakaze: A planned class of destroyers that roughly fills the "C-class" of destroyers starting and ending with the namesake Shimakaze. The Shimakaze needed to be as fast as greased lightning and were armed with three 5" dual purpose cannons and three quintuple torpedo launchers using the infamous Type 93 long range torpedoes. Anti-aircraft guns...well, they were there, just not in quantity. The class was considered too expensive for general production, and Shimakaze herself saw very limited service in the war until being sunk while escorting some troop transports.

Airplanes

Contrary to American propaganda, poorly made history documentaries, or just outright misunderstanding Japanese air doctrine, Japanese aviation was pretty much some of the finest on earth at the time. See, when your empire is built upon island chains, naval and air supremacy kinda become very important. As a result Japanese aircraft, while very poorly armoured (especially by American standards) and not quite as heavily armed compared to the allies, were nevertheless actually very well built, just in a very different way. In gamer's terms (since we are on /tg/), the Japanese airplanes were heavily min-maxxed for their intended role, relying on superior training and coordination between different types to get maximal efficiency out of the whole lot. This went swimmingly for them early in the war...but ended up in catastrophe after both attrition and lack of resources took their toll on both the quality of aircrew and machines alike.

Another quirk of Japanese military aviation had to do with internal bickering between the Navy and Army. The United States had a similar problem, but lessened the problem by delegating some roles to Navy, some to Army, with the rest of these problems being solved by not being a military dictatorship. For Japan meanwhile. . .well you could write an entire essay on the Imperial Japanese army and navy but the short answer is: They HATED each other and not only could not work together they sometimes undermined each other; for example with the navy for example not telling the army about how bad Midway was, screwing up the army plans in thinking there team had more carriers. The rivalry was so bad that when the military dictatorship was established the factions were essentially Army and Navy, and it wasn't uncommon for officers to murder each other and soldiers and sailors to get into knife fights before the war. In short, there was no Imperial Japanese Air Force, both the Navy and the Army kept their own air-wings and mostly they each had their own models of planes.

Also quick note about the "Kamikaze" or 'special attack force' strikes. The reason those strikes were even considered is that by the time, 1944. . . attacking a US naval task by air was already suicide. The sheer amount of Dakka that a US task group could out put was overpowering. By one count a single ship could launch over a thousand pounds of bullets into the air, per minute, and that doesn't even consider the introduction of proximate fuses. So if your going to die either way, may as well go for a one way trip as it increases your odds of something getting through.

Fighters

• Mitsubishi A5M "Claude": The less iconic, but still just as important naval aviation fighter designed by the same man who would develop the Zero: Jiro Horikoshi. Claudes were exclusively Navy aircraft that far excelled navy expectations, and helped end biplanes in IJN aviation service on Aircraft carriers. Early armament was two humble mgs, but variants after the A5M1a incorporated two 20mm Oerlikon cannons. Claudes were largely replaced by the Zero by the time the war broke out, but some were used in Kamikaze attacks in the latter part of the war. The design was so good that the IJA took a break from the dick slapping contest they had with the Navy to consider it, though they felt the maneuverability was lacking. Japanese aviators disliked closed cockpit designs on the A5M because they hindered visibility, so for the most part the aircraft were open topped, with all the positives and negatives that implied.
• Mitsubishi A6M "Zero": The Zero was the iconic aircraft of the war for Japan and served in every theatre, though it was first and foremost a Navy Fighter. It was designed so that a well trained pilot could fully utilize the aircraft and outmatch most anything in the world at the time. It was even good enough that the basic airframe (made from high-end alumuminum alloys and with revolutionary structures such as smoothed rivets) could be recycled for carrier use with minor modifications. This did have the downside of sometimes removing radios for increased range or due to them just not working, and by late war America and Britain started topping them with better armored and easier to fly designs. However, bear in mind that the Zero could achieve ranges of 1,870 km and was still able to accept upgrades until the end of the war, a feat not shared by every fighter.
• Kawasaki Ki-61 "Tony": When it was clear the Allies would not meekly stand down but come back to reclaim the ground Japan seized, the IJA requested a air superiorit fighter to protect their gains. Entered the "Tony", a radically different design from the other Japanese airplanes (so different, in fact, it was first believed to be an Italian airplane, hence, "Tony"). A decent albeit finicky design, its main achievement was to get the Americans to shit their bricks reconsider their approach, retire their P-40's and replace them with P-38's. Ultimately, a larger industrial base and better logistics won out, and the "Tony" was grinded away or bombed into oblivion.
• Nakajima Ki-84 "Frank": An Army Fighter that was put into service in 1944, designed specially to defend the homeland. Performance-wise, it was competitive with to superior to any other piston plane of the late war with its great blend of high speed, good maniability and hard-hitting armament. A solid design that nevertheless suffered from a tricky to nurse engine and finicky landing gear; problems that were compounded by lack of training for the pilots and materials shortages from the American bombing campaign.
  • Mitsubishi J2M "Jack": In a sense the Frank's 'little brother': a competitor design, decent but overall not as good. It was put into production alongside the "Frank" anyway since it used a different engine and few of the same resources; and the Japanese concluded that more airframes to try and intercept those pesky B-25's and B-29's simply couldn't hurt. No turbocharger on the engine meant it struggled to reach the bomber's operational altitude in time, but its quartet of hard-hitting 20mm cannons made it a dangerous opponent when it managed to properly intercept.
• Kyushu J7W Shinden: A high speed (750kph) short range prototype interceptor made in the last days of the war. Notably it had a pusher prop in the back and four 30mm cannons in the nose. Designed for the express purpose of ruining the day of those pesky American B-29's bombing the everloving shit out of Japan, but never saw more than a couple of test flights.
• Nakajima Kikka: A prototype Jet Fighter built by the IJN, similar in general shape to the ME 262 (albeit slimmer and lankier) with ten of them being built. It first flew on August 7th 1945, just after the American Atomic bombing of Hiroshima and eight days before Emperor Hirohito surrendered. Here more as credit to Japanese Engineers than anything.

Bombers

• Nakajima B5N "Kate": A torpedo and tactical bomber used by the navy and army starting in 1937. The B5N was one of the more advanced designs in the world at the time and was responsible for the sinking of Lexington and Hornet, and contributed to the sinking of the Yorktown. Possessing an impressive range of 1992 kilometers, a decent top speed of over 300kph and carrying an advanced long range torpedo they were able to launch from a further distance than equivalent weapons from other nations (or alternatively three 250kg bombs); they were a force to be reckoned with early into the war. But by 1943 fighter superiority was being steadily eroded from Japan, so the lack of defensive armament and armor started to bite the Japanese hard in the butt and even an improved version called the B6N "Jill" made to keep the design relevant couldn't invert the tendency.
• Mitsubishi G4M "Betty": A Bomber commissioned by the navy that could launch torpedoes as well, filling a similar role to the American B-25. Absolutely absurd, these vehicles had 3700km range at the expense of armament, bomb bay doors, and self-sealing fuel tanks in order to maximize range. The theory was that the Zeros would cover them so that being shot down wouldn't be a problem, but the harsh reality is that if anything with more than four light mgs (or anything heavier like Ma Deuces or 20mm cannons) shot at it, they tended to explode into flame, much earning them the nickname "the Honorable One-Shot Lighter" among allied pilots. Later variants added improved protection and armament at the expense of range, something Japan was not worried about in the latter part of the war. There was even a limited production run that was used to ferry Ohka flying bombs to launch positions, but these sucked ass. Yamamoto infamously was shot down in one of these by USAAF P-38 fighters, and you can still visit the wreckage in the jungle to this very day.

Misc

• Body Armour: The IJA fielded a few types of body armour in the 1930s and 40s. Several variants existed, but in short the basic idea was steel plate in canvas with padding. This was good enough to stop shrapnel and maybe some pistol fire, but not full rifle bullets, which would be good enough since most casualtys in war are caused by shrapnel. In general they were onto a good idea but could not outfit everyone with it.

Wunderwaffen

Much like the Germans, the Japanese were trying to get their own nuclear weapons program going, though they didn’t make very much progress with it. In fact, when the Americans dropped their own atom bombs, the Japanese initially refused to believe they were real due to the sheer amount of resources needed to refine Uranium. The Japanese also had domestic copies of the Me-163 and Me-262 fighters as well, but lacked the means to put them into production to be able to affect the outcome of the war.

All that said, they also had some unique domestic programs:

• MXY-7 Ohka: the infamous kamikaze airplane, as in being purposely built for the task. An Okha was basically an anti-ship missile... except is was piloted by a live human being instead of automated systems. A wooden airframe encompassing a rocket engine, a basic cockpit an a 1.200kg bomb, it could (and did) ruin the day of any ship it hit. It was mostly used during the battle for Okinawa (with some success), but they were extremely short-ranged (37km) and had to be dropped by Betty bombers... who were more often than not intercepted before they could launch the suicide plane. In typical Japanese irony, 'Ohka' means 'cherry blossom petal', petal that can only fall down once it becomes separated from its tree... Yeah... Pretty poetic, if you can somehow accept the fact there's a goddamn human being committing suicide to crash a 1,200kg bomb on target.
• I-400 series: a series of submarines that were designed as goddamn aircraft carriers. Each one could only carry about three floatplanes. Were deployed on missions but never actually got any use. Were captured and tested on by the US post war. Sunk in the 50s by the USN to prevent the Soviets possibly getting any ideas from the class.
• Fu-Go Balloon Bombs: Very basic in concept, these were weather balloons carrying shrapnel and firebombs that would be released after a fixed period by a very rudimentary timer. Launched in Japan, they’d travel the jet stream to America and hopefully cause enough damage and mayhem to disrupt American offensive operations in the Pacific. Completely incapable of any targeting, a few civilians were killed and American authorities clamped down on reports to prevent panic amongst the populace. Ultimately, these were the first truly intercontinental weapons ever made, but with only 300 of 9,000 total balloons being confirmed to have survived the flight to the USA they were a total waste of limited time and resources, even considering how dirt-cheap and simple to produce they were. The balloon bombs did succeed in forcing the Americans to divert a tiny amount of effort to trying to track them and combat potential forest fires.
• Atomic Bomb Projects: There were several projects for uranium enrichment. The Japanese had some good nuclear scientists, but ultimately the familiar limitations of limited industry and resources kept them from success. The Nagasaki group dropped a letter from Luis Alvarez to Ryokichi Sagane in the hope he could explain to the government what they were now facing, although the army didn't give it to him until after the war had ended.

• O-I Super Heavy Tank: Much like its ally Nazi Germany, the Imperial Japanese Army did have plans and may have made a prototype for a Super Heavy Tank, the concept of which came to light after the defeat of the IJA at Khalkhin Gol. It was commissioned by Hideo Iwakuro and development was started by the Army Engineering Division and later resumed by Mitsubishi Heavy Industries. It was to be multi-turret design like those experimented with in the inter-war years. The main armament was to be a type 92 105mm gun, with a type 1 47mm and three 7.7mm type 97 machine guns serving as a secondary in at least four other turrets. Armor was to be up to 200mm and was to be powered by the same engines used in the Type 5 Chi-Ri medium tank. The reason this is considered a wunderwaffen is due to the rather lack of a complete history and outlandishness of the design. Documentation does exists of how it was to be designed. A tank track is on display at the JGSDF fiji school. A prototype was rumored to be made but like with some treasure trains of Nazi Germany it may have been lost and scrapped to history. In the end it remains an obscure tank, with the documentation and history lost in the post-war.

Other

• NIGHT VISION: One of the more outstanding technological advancements that Japanese boasted was their rather impressive use of powerful binoculars, specifically on their naval vessels. In the interwar period, Japan had developed a superb optics industry, ranging from cutting edge photographic lenses to powerful long range sights. Most famous of these was the Nikko Nikon 120mm "Big Eye" binoculars. A tripod mounted system with enormous lenses designed to capture as much light as possible, it had the capability to see distant objects upwards of 20 miles away in low light conditions. The Japanese Navy used this capability to devastating effect in 1942 at the 1st Battle of Tsavo Sound, moving a cruiser squadron in radio silence and under cover of darkness, they snuck past the cordon of Allied ships guarding the perimeter of the Guadalcanal landing force, and ambushed the main body of American and British escorts, forcing them to flee and leave the Marines on Guadalcanal without most of their supplies for three months. However, due to the Japanese being overly cautious of a carrier counterattack the following day, they failed to press their advantage and withdrew, leaving the US fleet and Marines the fighting chance they needed to eventually recover.

• RADAR: Yes, they had RADAR and this came a surprise to the allies in 1942 when they captured some Japanese RADAR sets. Not the best RADAR systems that were a few years behind what the Brits and Yanks were doing, but nevertheless functional. The problem was they didn't use them for fire control. Of Yamato's three sets, none of them was arranged for fire direction.