IJN Musashi found

[Thanas]

CNN

(CNN)Microsoft co-founder Paul Allen says he has found the wreck of a long-lost World War II Japanese battleship near the Philippines.

The philanthropist posted images on Twitter that appeared to show the Musashi, once one of the two largest warships in the world. The discovery was made aboard his superyacht, the MY Octopus, as part of an expedition that Allen launched.

The search has taken Allen and his team of researchers more than eight years.

The images and video were taken by an unmanned submersible deployed from the vessel.

"Since my youth, I have been fascinated with World War II history, inspired by my father's service in the U.S. Army," Allen said in a statement.

"The Musashi is truly an engineering marvel and, as an engineer at heart, I have a deep appreciation for the technology and effort that went into its construction. I am honored to play a part in finding this key vessel in naval history and honoring the memory of the incredible bravery of the men who served aboard her."

He used his Twitter account to publicize the find. In one tweet, he said one image showed the bow of the ship, which features a distinctive chrysanthemum -- the flower is the emblem of Japan's royal family -- and a huge anchor.

The other underwater photograph shows one of the Musashi's valves on which the Japanese characters for "main valve handle" and "open" are legible.

He said the writing on the valve was proof that the ship was of Japanese origin.

The director of Japan's Kure Maritime Museum told CNN after viewing the information posted by Allen that it appeared that the vessel was the Musashi, although further pictures were needed to know for sure.

The Musashi was one of two Yamato-class battleships constructed by the Imperial Japanese Navy.

Launched in 1940, it was, at the time, the largest class of warship ever constructed, displacing more than 69,000 tons.

The Musashi sank on October 24, 1944, during the Battle of the Sibuyan Sea, part of the Battle of Leyte Gulf, in the central Philippines. According to U.S. Navy documents, torpedo planes from U.S. aircraft carriers scored at least 10 hits on the battleship over the course of four hours. Navy dive bombers also hit the ship 16 times, but it was the torpedo hits that doomed the Musashi.

"She went down by the bow, capsizing when the forward flying (U.S. forecastle) deck was submerged," said the Navy report, based on survivor accounts.

Two of those survivors, the executive officer and the chief engineer, told how they escaped the sinking.

"The executive officer swam off from one of the upper levels in the tower. He saw the propellers as Musashi disappeared," the Navy report said. "The chief engineer climbed over the side amidships as Musashi lurched to port. He walked and scrambled around the girth against the roll, climbing over the bilge keel. Finally, he was thrown off into the water and swam away to port. There were no explosions."

More than 1,000 of the Musashi's crew were killed during the battle and sinking. The 1,300-plus survivors were taken aboard by other Japanese warships, according to the U.S. Navy report.

Allen said that his superyacht, the MY Octopus, had found the wreck at a depth of around 1 kilometer (3,281 feet).

A statement released by Vulcan, Allen's company, said that the team combined historical data with advanced technology to narrow the search area, and that Allen had "commissioned a hypsometric bathymetric survey of the ocean floor to determine the terrain" before searching the area with a Bluefin autonomous underwater vehicle.

Kazushige Todaka, the maritime museum director, said that, given the location and the depth at which the wreck was found, he was "90% sure" that the ship was the Musashi.

"I was really surprised because the location of the sunken ship has never been identified since it went down. I have heard countless stories in the past that the ship was discovered, but they all turned out not to be true."

Todaka said Allen's team had been in contact with the museum about the ship's potential location and its expedition.

"It's a wonderful discovery, if it's true, as we have long been looking for the battleship," he said.

"It's fateful that the discovery was made on the 70th anniversary of (the end of) World War II. The memory of the war has been fading away after 70 years, and the survivors of the war are disappearing. It is very meaningful discovery and a good chance for us to remind ourselves about the war and its tragedy."

He added that images of the entire body of the ship will be needed to be 100% sure that the discovery is indeed the Musashi.

The Vulcan statement added that the team is "mindful of the responsibility related to the wreckage of the Musashi as a war grave and intend to work with the Japanese government to ensure the site is treated respectfully and in accordance with Japanese traditions."

[Thanas]

More info:
http://www.paulallen.com/Interests/Expl ... Expedition
http://propnturret.com/tully/viewtopic.php?f=6&t=2489

[Sea Skimmer]

I highly recommend the book Battleship Musashi by Akira Yoshimura for background on this ship and the shear paranoid insanity that was involved in creating her in near completely secrecy on the edge Hiroshima. Such that many details of the class have been lost completely and all of about a dozen photos exist of both ships.

Poorly designed, conceived on an extremely flawed basis and maybe the stupidest steel warship class ever laid down, let alone completed, Yamato and Musashi are damn incredible things anyway.

Since she didn't explode going down unlike Yamato and appears to be in excellent condition, and most importantly upright, we might learn a few new things about the class from her wreck. Of course the looting will soon follow too, but that's life. At least nobody is likely to blow up the entire wreck with explosives unlike certain ships lost in the North Sea and other shallow water wrecks. Though given what she represented and the colossal scope of her failure perhaps being looted is a fitting fate anyway.

[Purple]

Honestly I'd love to see her raised, rebuilt and refloated.

[Captain Seafort]

Honestly I'd love to see her raised, rebuilt and refloated.

Though given what she represented and the colossal scope of her failure perhaps being looted is a fitting fate anyway.

No, no, no. She's a war grave. End of story.

[Eternal_Freedom]

Honestly I'd love to see her raised, rebuilt and refloated.

Though given what she represented and the colossal scope of her failure perhaps being looted is a fitting fate anyway.

No, no, no. She's a war grave. End of story.

^This. Let the dead rest in peace.

That being said, I woudl be very interested in more detailed images/videos of the wreck.

Oh and Purple? You seriously want to try raising a 70,000 ton wreck from a kilometre down...and then rebuild her, a type of ship not constructed for 70+ years? Dream on.

[Purple]

But... but... how will we save the earth?

[Isolder74]

Awesome. This reminds me to bug my brother to finish the Musashi Model that I gave him years ago. He keeps telling me he can't do it because he has nowhere to display it. Maybe I should just build the kit myself.

They may have been dead weight in the Carrier age but man did they take a ton of munitions to put down.

[Borgholio]

This is fantastic. I'm glad they finally found her. Too much about the Yamato-class remains unknown due to the level of secrecy that was involved in their construction. The fact that the Yamato was blown to bits didn't help matters. Hopefully they can learn a great deal by studying Musashi.

Oh and Sea Skimmer, you think the Yamato-class was stupid? Think about what they were planning to build had Midway not turned against them? The A-150 class with 18" side armor and 20" guns. Talk about crazy.

[Pelranius]

As I recall, the 18" armor for the A-150 was actually planned to be two sheets of thinner steel pressed together, since Japanese mills couldn't roll steel that thick.

Besides, didn't the Yamato class already have trouble keeping up with the IJN's carriers due to somewhat slower speeds (you'd think someone would have noticed during the design phase, and the IJN was supposed to be the grown ups in the Japanese military).

[Vendetta]

Besides, didn't the Yamato class already have trouble keeping up with the IJN's carriers due to somewhat slower speeds (you'd think someone would have noticed during the design phase, and the IJN was supposed to be the grown ups in the Japanese military)

It was common at the time for carriers to be faster than battleships. The difference in speeds between the Yamato and Japanese carriers was a little greater than that between US carriers and battleships, but not amazingly so (a few knots).

[Isolder74]

For ships of their size and tonnage the Yamato-class ships were surprisingly fast. Compared to the Akagi and the Kaga, arguably the best of the Japanese carriers, it was close enough in speed to be able to support them in combat.

[Thanas]

Wouldn't designed cruising speed be more important than top speed? Because the main job would be to travel with the carriers. Does anybody know the designed cruising speed for the Yamato and Japanese CVs?

[Borgholio]

I don't know what the designed cruising speed is, but both the Yamato class and carriers such as the Sōryū had roughly the same "most efficient" speed (16 knots vs 18 knots). Max speed though put the Soryo at 6 or 7 knots faster though.

[Thanas]

Thanks.

[Sea Skimmer]

Since Kaga could only make 28 knots on a really good day by ~1940 the top speed of Yamato actually wouldn't have been a real problem accompanying Japanese fast carriers groups in the early war. US ships of similar speed could usually keep up too, only falling slightly behind if the carrier did go to top speed for a short period to launch planes or evade attack.

Japan did not consider accompanying carriers a relevant design requirement at any point though.

Prior to 1940 all Japanese carrier doctrine called for dispersed single carrier task groups to operate ahead of the main body with no more then cruisers for escort. Only in 1940 did they radically change doctrine and form Kido Butia which was accompanied by battlecruisers formally intended to be the main body vanguard. Better battlecruisers were planned ~1940 in the form of the B-65 class, but this was in reply to the announcement of the US Alaska class and part of the Japanese Circle 5/6 building programs which had just about zero connection to industrial realities. Those are also the programs that give us the plan for five Yamatos to be followed by at least two with 50cm guns. That was magically supposed to be done alongside a mountain of other hulls by something like 1947.

Kido Butai replaced the original cruiser-battlecruiser vanguard force and the dispersed carrier groups, though a smaller surface action vanguard was kept in virtually all Japanese operations between the opening strike on Oahu and the disaster at Midway. The main body of battleships remained center to strategy right up to that point. Anyway the foolishness of this is long discussed.

The 28 knot speed was intended to give Yamato absolute superiority over the old US battleships, which Japan hoped Yamato could beat two to one, and be equal in speed to any reasonable 35,000 ton treaty battleship. They had wanted 31 knots because 45,000 ton ships could certainly be faster but this turned into either very big ships, or ships which didn't have a wide immunity zone against 18in gunfire the way Yamato did.

Speeds over about 30-31 knots are very expensive in any surface warship design though. Going 33 knots can involve twice the power as 30, and 30 knots twice the power of 25 knots. The Iowa class vs South Dakota is a pretty good example of this in action, though the .7in increase in deck armor adds up to a lot of weight too, more so then the 50cal guns IIRC. Aircraft carriers can get away with being fast because the actual aircraft payload is fairly light, and while the heavy aero fuel and munitions can be stored very low in the ship. Armor and heavy guns are on average high, demanding bigger hulls to support the same mass. Thus its harder to make the ship go fast.

Most utter economical cruising speeds are actually generally not that relevant to combat service, because they are too slow to avoid diesel submarines. They also often require running just one or two shafts on a big ship which is undesirable least you be hit the wrong spot and suddenly have no engines online at all. If you have all four shafts going your best cruising speed can actually be higher without wasting fuel. It can actually be hard to go slow, because of the minimal throttle settings for good running of the turbines. The Iowa class had something crazy like 20,000nm range at 13 knots on just one shaft, but nobody would ever actually do that in wartime. 17-20 knots would be a typical cruising speed for warships, while sustaining speeds over about ~25 knots would be avoided except in immediate action because of the fuel consumption.

Generally fuel burn on your destroyers was by far the main limitation anyway. Early war though some carrier groups operated with only cruiser escorts, such as the Doolittle Raid on Japan. Destroyers could never have kept up.

[Sea Skimmer]

As I recall, the 18" armor for the A-150 was actually planned to be two sheets of thinner steel pressed together, since Japanese mills couldn't roll steel that thick.

They managed to roll 25in thick faceplates!

As far as I can tell rolling thickness wasn't the issue, they'd already built some heavier machinery for Yamato anyway and could have built more for such a project. It was instead a broader quality control problem and a problem encountered by other navies too, an ongoing one in fact. Over about 13-14in quality of face hardened armor started to drop off because it was too difficult with the technology and steels of the era to control the face hardening process with accuracy. As the plate got bigger the margin of error scaled up too and the impurity of the material counted for more.

For turret faceplates which already had to be cut for gunports the solution was a large increase in thickness to compensate for the loss of strength. These special plates also got extra quality checks (which turns into a lot of money resmelting the armor) not feasible in the much larger number of belt plates. They still had problems though, but in the end made up only a tiny portion of the ships target area anyway.

An alternative solution was to make two plates and bond them together, accepting a penalty of strength from that, two plates will always be weaker, but exploiting the chance to make the outer plate harder then it otherwise could be. Compound armor like this was made in the early era of steel warships, but replaced by face hardening processes. The principles behind it are the same as are behind modern composite armor for ground vehicles.

However it would only make sense with this kind of steel armor if you had a really stupid thick belt, and the A-150 was basically the only ship around to get big enough even on paper to seriously consider it in WW2. If you can call that ship serious. I'm sure it was from the designers standpoint.

At times it was also suggested for US ships, such as the infamous Tillman Maximum Battleships back around WW1, but not implemented in favor of limiting belts to 13.5in producable with good qaulity. Angling belt armor generally helped the situation anyway and appeared in this era, simply requiring a greater height of the same thickness of plate for improved protection rather then thicker plates. But again, get huge enough and that isn't going to work well, since it steadily increases the amount of the ships beam compartmentation which is not armored. Yamato had the armor belt as far outboard as possible and linked into the heavy anti torpedo-diving shell bulkhead.

Indications are A-150 would have been the same but we functionally know almost nothing about the project. Japan burned everything possible on the Yamato, A-150 and multiple cruiser and carrier projects when the war ended. Since they'd always kept tight information control on ship designs and the builders for these classes it was easy to destroy almost all information.

[Pelranius]

Ah, thanks Sea Skimmer.

I will have to stock up on IJN capital ship books one day.

[Sea Skimmer]

Not so many good books exist on them simple because of the information vacuum. At least I'm waiting to be pointed towards a really good one. Battleship Musashi is pretty interesting though for the civilian builders point of view of actually getting the ship built in secret on the edge of Nakagaki.
http://www.amazon.com/Battleship-Musash ... 4770024002

I've largely just collected bits of information from the internet and a myriad of books and sources and USN technical mission reports complied in 1945-46 over the years.

http://www.amazon.com/Japanese-Cruisers ... 0870213113
Keep an eye on this book though. The price appears to have skyrocketed from the print run being sold off, but the naval institute press puts old reference books back into print from time to time when they see the resale market surging on them.

Basically this is the best naval reference book EVER, and it would be utterly amazing if we were to get such works on anyone else's cruisers. Its not battleships, but the book explains a huge amount of the technical basis of the IJN and its battle strategy and operational planning. It covers the details of the ships designs, modifications and extensive service histories accounting for more or less everything they did. Since few operations of note in the Pacific didn't involve Japanese cruisers this is basically everything in the naval war touched on. And it has full plan views and cross sections of every ship actually built, and line drawings of a couple unbuilt projects of varying plausibility as well as the carrier conversion conducted on Ibuki.

[Isolder74]

Another good place to look for information on the Imperial Japanese navy is Combined Fleet a web site run by Jon Parshall one of the most read and researched writers about the Japanese Navy and the Pacific war.

[SAMAS]

Nice to know we're ready in case of Gamilan invasion.

[Pelranius]

Thanks again.

This will make for a refreshing break from my current habit of reading about oligarchical misrule and power structures in the post Soviet states.