The Daily Bounce

WOT Leaks, WOWS Leaks, News and much more!

TDB Home » Supertest: Japanese Tier X Freemium Battleship Yashima

Supertest: Japanese Tier X Freemium Battleship Yashima

8 min read

The Design A-150 was the last design of battleships made by the Imperial Japanese Navy. Design studies for this new class began in 1938 with the idea being to build battleships that would even dwarf the Yamato-class and that would outclass anything that the U.S. or British Navies could build in case the specifications of the Yamato-class where revealed.

Battleship Design A-150. Detail from a painting by Richard Allison. Scanned from “Battleships: Axis and Neutral Battleships in World War II.”

The initial plans were calling for ships that would displace over 90 000 tons with an armament consisting of 8 or 9 510 mm guns in twin or triple turrets. This would have been completed by a secondary battery consisting of multiple dual-purpose twin turrets with 100 mm guns.
The armor protection would have been just as impressive with what could have possibly been a 460 mm main belt.

The design was later revised as it was judged too large and too expensive so it was brought down to the size of a Yamato-class. This version would have kept the 510 mm guns but this time, limited to 6 guns in 3 twin turrets. The armor was also be brought down to the 410 mm main belt that was already present on their predecessor. This design would have basically been a modernized version of the Yamato-class and if Japan ever went through with it, they would have most likely completed already laid-down hulls. Of course, this implies that Japan would have kept building Yamato-class ships but since war broke out, such work was delayed to focus on smaller ships and carriers.

For as much as we know, 2 ships were planned to be built with the first “Number 798” that would have been built in Yokosuka, in the same shipyard as Shinano and “Number 799” in Kure.

The biggest problem of this design is the limited information on it. At the end of the war, the Japanese Navy destroyed a lot of documents on possible designs they worked on and this included the A-150 design.

For the guns themselves, 2 guns and a gun mount were ordered at the Kure Navy Yard in June 1941 but construction was halted with the start of the Pacific War.

In World of Warships, the Yashima presents what would have been the “Modernized Yamato” A-150. She carries 3 twin turrets with 510 mm guns and a secondary battery with a mix of 155 mm guns and 100 mm guns. For the anti-air, it’s a bit awkward because she is armed with both 40 mm AA guns that were copied from stolen 40 mm Bofors and the completely obsolete 25 mm AA guns that were as effective as insulting the pilots of enemy planes. Then again… It’s not the first time that we see that kind of thing in the game.

Another thing, the Yashima has the “Battlecruiser” dispersion formula that can be found on Alaska, Stalingrad, Georgia or Thunderer for example.
These guns are also supposed to have a new unique gun sound and I hope that it will actually sound like you are shooting 2 tons heavy shells at the enemy.


Gun Fire Control System
Main battery


Propulsion: 158 000 hp

Type10 mod. 1

510 mm/45 Type 98
GeneralMain BatterySecondariesAir DefenseConsumables
Health97 200 HP
Displacement72 800 tons
Main Armament
Maximum Firing Range26.630 km
510 mm/45 Type 983 x 2 510 mm
Secondary Armament
Maximum Firing Range7.000 km
155 mm/60 3rd Year Type
100 mm/65 Type98
2 x 3 155 mm
10 x 2 100 mm
Maximum speed27 kts
Turning Circle Radius900 m
Rudder Shift Time18.7 s
Surface Detectability18.0 km
Air Detectability12.78 km
Detectability After Firing Main Guns in Smoke20.92 km


3 x 2 510 mm/45 Type 98
 Reloading Time35 s
180 Degree Turn Time60.0 s
Optimal firing angles at the front34°
Optimal firing angles at the rear30°
Sigma2.1 sigma
Maximum Dispersion272 m
Type of Projectile HE – 510 mm HE Type 98
Alpha Damage8 100 HP
Damage6 060 HP
Penetration capacity 84 mm
Explosion size3.27
Fire chance40 %
Projectile Speed720 m/s
Air Drag0.32
Projectile Mass1 985
Type of ProjectileAP – 510 mm AP Type 98
Alpha Damage19 400 HP
Chance to Cause Fire-0.5 %
Projectile Speed720 m/s
Air Drag0.32
Projectile Mass1 984
Projectile Krupp2 850
Projectile Detonator0.033 s
Detonator threshold170 mm


2 x 3 155 mm/60 3rd Year Type
Reloading Time12.0 s
Sigma1.00 sigma
Type of ProjectileHE – 155 mm HE Type0
Alpha Damage2 600 HP
Damage630 HP
HE penetration25 mm
Explosion Size0.55
Chance to Cause Fire10 %
Projectile Speed925 m/s
Air Drag0.335
Projectile Mass55.87
10 x 2 100 mm/65 Type98
Reloading Time3.0 s
Sigma1.00 sigma
Type of ProjectileHE – 100 mm HE Type98
Alpha Damage1 700 HP
Damage280 HP
HE penetration24 mm
Explosion Size0.28
Chance to Cause Fire6 %
Projectile Speed1 000 m/s
Air Drag0.331
Projectile Mass13


10 x 2 100 mm/65 Type98
Sector range0.1 km – 5.8 km
Hit chance75 %
Sector’s damage67
Sector’s damage frequency0.29 s
Sector’s damage per second235
Flak clouds number10
Flak cloud damage1 540
24 x 2 40 mm/60 Type5
Sector range0.1 km – 3.5 km
Hit chance75 %
Sector’s damage125
Sector’s damage frequency0.29 s
Sector’s damage per second438
16 x 3 25 mm/60 Type96 Triple
Sector range0.1 km – 2.5 km
Hit chance 85 %
Sector’s damage29
Sector’s damage frequency0.29 s
Sector’s damage per second102
Slot 1
Slot 2
Slot 3
Damage Control Party I
Work time: 10 s
Cooldown: 120 s
Repair Party I
Number of charges: 3
Work time: 28 s
Cooldown: 120 s
HP regeneration speed: 0.5% HP/s
Spotting Aircraft I
Number of charges: 3
Work time: 100 s
Cooldown: 360 s
Bonus: +20% Maximum firing range
Damage Control Party II
Work time: 10 s
Cooldown: 80 s
Repair Party II
Number of charges: 4
Work time: 28 s
Cooldown: 80 s
HP regeneration speed: 0.5% HP/s
Spotting Aircraft II
Number of charges: 4
Work time: 100 s
Cooldown: 240 s
Bonus: +20% Maximum firing range
Fighter I
Number of charges: 2
Work time: 60 s
Cooldown: 135 s
Patrol radius: 3.0 km
Squadron size: 4 planes
Fighter II
Number of charges: 3
Work time: 60 s
Cooldown: 135 s
Patrol radius: 3.0 km
Squadron size: 4 planes

The armor


The Yashima presents almost the same armor scheme as our beloved Yamato. There are a few differences that I will detail during this small analysis.

The bow section



The bow is protected by 32 mm of armor with the exception of a part of the deck that is 50 mm thick. This 50 mm section will at least provide some additional protection against HE shells from cruisers in general.


For the citadel’s athwartship, it’s the same as Yamato with the infamous cheeks. The lower part is 350 mm thick and heavily sloped and the upper part is 340 mm thick, also with a slop that can prove itself to be useful against penetrations through the bow.

For the cheeks, I guess that by now, everyone knows how they work. Wait for the ship to be a bit angled and the AP shells from the large-caliber guns will be able to go through the bow and then penetrate the angled plates on each side.

Above the citadel, there is a small 25 mm casemate on each side of the barbette.

The middle section


The deck of the Yashima is 57 mm thick which means that most HE shells from cruisers will shatter outside of the ones from the British 234 mm guns or from supercruisers and German cruisers using IFHE.

The sides are only 32 mm thick which means that even though they are quite thin, they won’t protect the ship from HE shells of cruisers.

For the main belt, it’s 410 m thick which is very good and it’s sloped at 19° to increase the effective thickness.


For the horizontal protection, outside of the weather deck, she only has her main armor deck. It is 200 mm thick except for the sloped sides that are 235 mm thick. This means that she is protected against AP bombs of the Enterprise and the Shokaku but Hakuryu will still be able to score citadels reliably.

The stern section


For the stern, it’s the same as the bow. The biggest portion is protected by 32 mm of armor except for the deck above the hangar that is 50 mm thick.


The citadel’s athwartship is also the same as the one at the front. 340 mm upper part and 350 mm lower part with the big cheeks on each side. As you can see, the steering gears are also protected by 350 mm of armor.

The superstructure


For the superstructure, there are some small differences with the Yamato because of the different secondary and AA armament but overall, it’s not smaller or bigger. This superstructure is protected by 19 mm of armor except for the barbettes of the 155 mm secondaries that are 75 mm thick and for the funnel that is 50 mm thick.

That funnel is actually quite different from the one on the Yamato and Musashi. It is going inside the ship and goes all the way to the deck level whereas, on the Yamato, it stops on the “floor” of the superstructure. The barbettes of the 155 mm secondaries are also connected to the citadel deck while on the Yamato, they are stopping on the weather deck.


The turrets


The turrets have a few differences with those of Yamato. The face remains the amazing plating of 650 mm with a 45° slope. The sides are for the first part 250 mm thick and for the second part 225 mm thick compared to the constant 250 mm on Yamato. However, while on Yamato, the back of the turret is only protected by 190 mm of armor, on Yashima, it’s 250 mm thick.
For the roof, the Yashima has better protection with 290 mm of armor with the exception of the backend that is only 270 mm thick. On Yamato, it’s a constant 270 mm of armor.

Finally, the barbette is 510 mm thick which is more than enough to resist most AP shells that could possibly hit it.

Personal opinion

For now, I’m slightly interested in how the Yashima could possibly perform. The thing is that the guns don’t gain any overmatch capability compared to the Yamato (unless all of sudden, ships with 35 mm external plating appear) and the alpha damage per volley is lower (116 400 vs 133 200). Also, the Yashima has the problem of having a much longer reload of 35 seconds. However, the ship has an absolutely ridiculous penetration power that beats every other battleships in the game. There aren’t many platings that can effectively resist her.

When it comes to the super high armor threshold of 170 mm… for now, I will wait because I highly expect that value to go down. It basically means that the ship will get overpenetrations very often on anything that isn’t heavily armored which… isn’t very good, especially with only 6 guns.

Also… when I see her secondaries, I’m almost tempted to meme around with a secondary build just to experience having a Harugumo strapped on each side of the ship.

Now as a side note, when I was looking at her 3D model, I found this:


It’s definitely an easter-egg and not just a random pattern. My personal guess was that it’s a coastline somewhere but I really can’t find something that corresponds.

If anyone on Reddit knows what/where it could possibly I would really appreciate knowing the answer.

15,466 thoughts on “Supertest: Japanese Tier X Freemium Battleship Yashima

  1. you are wrong – its proposed project A-140F7 ( Yamato ) and nothink more. A-150 was a 4 turret design.
    In game the ship has normal IJN BB dispersion formula.
    bro, you are starting being worse and worse.
    I´d rather not read everythink, dont have so much time.
    But you trust me, ST here, so I know, what I am talking abut.

  2. Well hello Schneider or should I call you bismarck381mm.

    While I may be wrong regarding the origin of the Yashima (even though you are also wrong because the 4 turrets design was only one of the proposals), I think that for the dispersion, I already proved you by A+B that you are wrong.
    I gave you the proofs for it, but somehow, you manage to still come back without anything to back up your affirmation except for the fact that apparently, for you 276 m and 272 m are the same value.

    What about you finally admit that you are wrong and stop your dumb parade?

    Ah and… “YourCorrector”? Seriously? Start by writing properly and then we can talk.

  3. Halloo again,
    After what we ( with your friend ) debated on Reddit about this stuff, I realised that you are right in the dispersion fromula case.
    What I forgot, was came here and check your answer, cause I expected somethink to be in my mailbox.
    Apologise for that.
    Well, my english is not the best, but hopefully good enough to apologise you for these inconveniences.
    While we cleared up all the stuff on Reddit, plss, just delete this conversation, its pointless.
    Have a nice evening, good bye.

Comments are closed.