Sealion II hits Yamato instead of Kongo

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winterfell
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Sealion II hits Yamato instead of Kongo

Post by winterfell » Sun Aug 17, 2014 11:39 pm

On November 21, 1944 Sealion II hit Kongo with 2 torpedoes of the 6-torpedoes salvo running at the depth 8 feet. Kongo sunk 3 hours later.

However, Kongo wasn’t alone there as Yamato, Nagato and smaller ships were also present.

Let’s assume that Yamato was a target of aforementioned salvo and:
• was hit with four torpedoes running at the same depth of 8 feet,
• distribution of hits: 1 - 25 meters (80 feet) from the bow, 2 - below of second turret of main artillery, 3 – in area of machinery plant, 4 – aft, behind the citadel, but without any direct damage to propellers, rudders etc.

Was there any chance that Yamato would be sunk in the result? She was giant, but her system of underwater protection was far from being perfect. In December 1943, Skate hit Yamato with one torpedo in place where her underwater protection system was widest, but she ended with 3000 tons of water in hull.
Kongo aggravated her damages while trying to run from pursuing Sealion II. I believe that Yamato would try (would have to try) to do the same. I assume however that there would be no additional hits for Sealion II as all Japanese ships would be protecting Yamato.

In my opinion there are 30% chances that Yamato would be sunk (Shinano was sunk after 4 torpedo hits, but she had untrained crew, was only partially completed and definitely not battle ready).
However Yamato wouldn’t be able to get to Japan with such damages (if she try, she would eventually sink on the way). Only way to save her would be decision to steer to Formosa/Taiwan. I don’t know however if was there any port with infrastructure necessary to conduct repairs of such scope on such a big ship. If not, for some time she would face similar fate to Takao’s in Singapore. However, sooner or later American aircraft carriers would destroy her.

Garyt
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Re: Sealion II hits Yamato instead of Kongo

Post by Garyt » Wed Dec 10, 2014 8:39 pm

Can't compare the Yamato to the Shinano. Best comparison is to the Musahi, or even the Yamato herself when sunk.

The Yamato took 3 sets of about 4 torpedoes over a few hours. First set did little other than causing a slight list and require flooding. Second set slowed her and required more counterflooding, and the third set sunk her. This was in addition to the many bombs that struck her.

So in your scenario, the Yamato continues underway, counterfloods to correct a minor list, and loses little speed. Of course the repairs would be an issue as you suggest, she might be out of service for the war. But if need be, I don't think there would be a problem getting to Japan, other than she could not procede with much speed and maybe subject thereby to attacks from the air again.

Steve Crandell
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Re: Sealion II hits Yamato instead of Kongo

Post by Steve Crandell » Wed Dec 10, 2014 9:01 pm

There is a huge difference between 4 hits on the same side of the ship at the same time and a lot of hits on both sides over several hours. The eight foot depth would cause a lot less damage than a deeper running torpedo, but I suspect the eight foot setting was used because the submarine crew knew their torpedoes were actually running much deeper than the depth setting.

The post war study done by the US opined that 4 torpedoes on the same side of a Yamato class battleship would cause her to sink. I suspect that means over a short period so there is no time for effective counterflooding.

Garyt
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Re: Sealion II hits Yamato instead of Kongo

Post by Garyt » Wed Dec 10, 2014 9:27 pm

There is a huge difference between 4 hits on the same side of the ship at the same time and a lot of hits on both sides over several hours.
I understand that. The Yamato though took torpedoes concentrated on the port side in rapid sucession. THe attacks were roughly over 2 hours in total duration - but they were really 3 waves, and in each wave the Yamato was struck by 3-4 torpedoes to port.

The difference between the Yamato and the Musahi is that with the Musahi they did not concentrate on the port side, and that is why IMO it took 11-20 torpedoes to sink her.

Steve Crandell
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Re: Sealion II hits Yamato instead of Kongo

Post by Steve Crandell » Wed Dec 10, 2014 11:21 pm

When a ship is hit by 20 torpedoes and sinks, that does not mean it would take 20 torpedoes to sink the ship.

Garyt
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Re: Sealion II hits Yamato instead of Kongo

Post by Garyt » Thu Dec 11, 2014 12:56 am

When a ship is hit by 20 torpedoes and sinks, that does not mean it would take 20 torpedoes to sink the ship.
\

That is indeed true - however, as these were hits over time, not all at once, the Musahi had ample opportunity to sink between hits. I think she had taken around 15 by the last attack - and was still floating reasonably well. A bit low in the water, but very little list.

Steve Crandell
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Re: Sealion II hits Yamato instead of Kongo

Post by Steve Crandell » Thu Dec 11, 2014 1:00 am

Garyt wrote:
When a ship is hit by 20 torpedoes and sinks, that does not mean it would take 20 torpedoes to sink the ship.
\

That is indeed true - however, as these were hits over time, not all at once, the Musahi had ample opportunity to sink between hits. I think she had taken around 15 by the last attack - and was still floating reasonably well. A bit low in the water, but very little list.
A BIT low in the water? You mean the foc'sl being awash?

Garyt
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Re: Sealion II hits Yamato instead of Kongo

Post by Garyt » Thu Dec 11, 2014 2:22 am

Well, looking back at it, I was thinking when it was still making 20 knots, but that was after 11 torpedoes. She had lost about 12 feet of freeboard by this time.

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