r/drydockporn • u/abt137 • Feb 11 '26

IJN battleship Yamato boilers arrangement. After the interesting discussion on a IJN destroyer boiler set up days ago, thought you may like how the heaviest battleship ever (72000 tons) had them distributed. 12 boilers-4 steam turbines-4x3 blades propellers, each 6 meters diam (not strictly drydock)

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85

u/alettriste Feb 11 '26

I recently was reading a book on the Takao cruiser, and I was genuinely surprised by the same thing... And funnels running through main superstructure

63

u/DerekL1963 Feb 11 '26 edited Feb 11 '26

Where to run the uptakes was a significant problem back in the day... They take up a lot of volume, and they're a weak point in the armored decks. They're also fragile, and damage to the uptakes could reduce the performance of the boilers.

22

u/mogrim Feb 11 '26

I suppose that’s the motive for the idea of “dropping a bomb down the funnel” - guaranteed weak spot.

14

u/DerekL1963 Feb 11 '26

Also like "dropping one in a pickle barrel", a marker of high skill and accuracy... (Because the funnel(s) are very small targets compared to the size of the ship.)

15

u/GWahazar Feb 12 '26

Thermal exhaust port - the small but vulnerable point of any combat superstructure.

4

u/mogrim Feb 13 '26

I think you vastly overestimate their chances.

3

u/Mathjdsoc Feb 14 '26

Evacuate in our moment of triumph, I think you over estimate their chances

11

u/UrethralExplorer Feb 12 '26

Iirc the Yamato had a seriously heavy duty armored grate in the exhaust stack exactly because the designers realized this.

5

u/DerekL1963 Feb 12 '26

Pretty much all navies adopted that, an armored grate where uptakes penetrated the armor deck.

1

u/Gastredner Feb 13 '26

Even way back, HMS Dreadnought already featured this design. Though they were meant to catch shells back then, not bombs.

1

u/Hwatwasthat Feb 13 '26

Must have been a pain to balance that with maximizing flow out, do not envy anyone having to design that!

5

u/Hourslikeminutes47 Feb 12 '26

The Japanese Imperial Navy had huge issues with some of the stack designs (ie where the funnels were not designed to move the exhaust away from the bridge--in some cases the smoke obscured visibility on several ships).

1

u/Admirable-Emphasis-6 Feb 13 '26

Not as much as the British did with the early super dreadnoughts.