The Largest Submarines in World War II

[GT182]

These subs were the precursor to our own 50's cold war Regulus Class subs and the Nuke subs of today. The Japanese I-400 and I-401.

https://www.youtube.com/watch?v=OPC51Mh-jtU

Imagine a sub simulation using these two subs.

[Kptlt. Neuerburg]

I recently read a book titled Operation Storm which talks about what the Japanese planned to do with the I-400 submarines. I've even seen the only remaining Seiran aircraft which where built for the I-400s at the Uvdar- Hazy Center in Chantilly, VA.

In 1941, the architects of Japan's sneak attack on Pearl Harbor planned a bold follow-up: a potentially devastating air raid—this time against New York City and Washington, DC. The classified Japanese program required developing a squadron of top secret submarines—the Sen-toku or I-400 class—designed as underwater aircraft carriers, each equipped with three Aichi M6A1 attack bombers painted to look like U.S. aircraft. The bombers, called Seiran (which translates as “storm from a clear sky”), were tucked in a huge, water-tight hanger on the sub’s deck. The subs' mission was to travel more than halfway around the world, surface on the U.S. coast, and launch their deadly air attack. This entire operation was unknown to U.S. intelligence. And the amazing thing is how close the Japanese came to pulling it off. http://www.amazon.com/Operation-Storm-Japans-Secret-Submarines/dp/0770435734

[Commander Wallace]

These subs were the precursor to our own 50's cold war Regulus Class subs and the Nuke subs of today. The Japanese I-400 and I-401.

https://www.youtube.com/watch?v=OPC51Mh-jtU

Imagine a sub simulation using these two subs.


I remember a documentary on these Submarines. The Sen Toku class were essentially aircraft carrier submarine that carried 3 Aichi M6A sea planes. (https://en.wikipedia.org/wiki/Aichi_M6A)

https://en.wikipedia.org/wiki/I-400-class_submarine

Only 3 were ever built but it showed the Japanese military were forward thinkers. The I class could carry enough fuel to circumnavigate the globe 1 and one half times.The U.S took possession of them after WW2 concluded to study them. The Soviet Union learned of them and demanded one or more be turned over to them . The U.S instead took the Subs and used them for gunnery practice, destroying them all.

Fantastic read and video.

[Stealhead]

They actually just took them to sea and scuttled them not as gunnery targets.

I think they are very interesting concepts however they realistically could not do very much with just three aircraft and they where too large to be effective in the type of submarine warfare that was effective during WWII. Though they did give the US Navy the idea to design hangers for early post war cruise missiles. So the I-400s did have an influence upon the advancement of post war subs.

[CaptainRamius]

They actually just took them to sea and scuttled them not as gunnery targets.

I think they are very interesting concepts however they realistically could not do very much with just three aircraft and they where too large to be effective in the type of submarine warfare that was effective during WWII. Though they did give the US Navy the idea to design hangers for early post war cruise missiles. So the I-400s did have an influence upon the advancement of post war subs.

But imagine this: your driving along in your nice Gato class when suddenly this monster surfaces next to you. It's the size of a ballistic missile submarine. It's huge. :arrgh!:

[Commander Wallace]

They actually just took them to sea and scuttled them not as gunnery targets.

I think they are very interesting concepts however they realistically could not do very much with just three aircraft and they where too large to be effective in the type of submarine warfare that was effective during WWII. Though they did give the US Navy the idea to design hangers for early post war cruise missiles. So the I-400s did have an influence upon the advancement of post war subs.


No. Actually as I said, they were destroyed in weapons exercises by the U.S Navy.

https://en.wikipedia.org/wiki/I-400-class_submarine

under Artifacts in the wikipedia.org article is this .

quote :
Artifacts

The wreckage of I-401 was discovered by the Pisces deep-sea submarines of the Hawaii Undersea Research Laboratory (https://en.wikipedia.org/wiki/Hawaii_Undersea_Research_Laboratory) in March 2005 at a depth of 820 meters.[34] (https://en.wikipedia.org/wiki/I-400-class_submarine#cite_note-34)[35] (https://en.wikipedia.org/wiki/I-400-class_submarine#cite_note-35)[36] (https://en.wikipedia.org/wiki/I-400-class_submarine#cite_note-36) It was reported that the I-400 was later found by the same team off the southwest coast of the Hawaiian island of Oahu in August 2013[37] (https://en.wikipedia.org/wiki/I-400-class_submarine#cite_note-37)[38] (https://en.wikipedia.org/wiki/I-400-class_submarine#cite_note-fly2015-05-38) at a depth of 700 m (2,300 ft).[39] (https://en.wikipedia.org/wiki/I-400-class_submarine#cite_note-39) Jim Delgado, a researcher working aboard the Pisces V (https://en.wikipedia.org/wiki/Pisces_V), told the Chicago Tribune (https://en.wikipedia.org/wiki/Chicago_Tribune) "It was torpedoed, partially collapsed and had sunk at a steep angle."[40]
(https://en.wikipedia.org/wiki/I-400-class_submarine#cite_note-40)


I read an account where officers on board a Navy destroyer reported shelling the Submarine. At the very least, according to the article, I-400 had been hit by a torpedo and sunk.

You had said it had been scuttled at sea. I said this as well. The article however suggests I-400 had help being " scuttled " in the form of live fire exercises, specifically torpedoed. I should have specified torpedoed . This article however doesn't address the demise of the other 2 subs.

[Aktungbby]

http://www.operationstormbook.com/i400_images.html (http://www.operationstormbook.com/i400_images.html)

[CaptainRamius]

http://www.operationstormbook.com/i400_images.html (http://www.operationstormbook.com/i400_images.html)

Great photos. The I-400 performs well, travels well, fights well, and looks great!
I think it's one of the best looking subs of WW2 (apart from the Gato and Type VII) :salute: