"Japan's Monster Sub" Topic

"Jules Verne's fictional "Nautilus" submarine had every comfort, including a pipe organ and picture windows. But even Verne's fertile imagination would have been overtaxed by the possibility of submarines large enough to have hangars that could each carry and launch three bomber aircraft. It's a notion that wouldn't even have appeared in the daydreams of an errant 20th century schoolboy. But born of desperation, just such a monster submarine actually made its little-known appearance in World War II.

The Allied successes in the naval battles of Guadalcanal convinced the Japanese General Staff that the war was going badly and that November 1942 had marked a turning point for the worse. Drastic action was needed, and Japanese naval planners realized they must play into their strength. They knew they were ahead of the Allies in many elements of submarine technology, having far more classes of submarines in addition to the world's most effective torpedo, the Type 95. They were also convinced that their air power capability was superior. But they had no illusions about what they were up against in having taken on the world's mightiest industrial power. They decided that the war must now be taken to the enemy, and to do that successfully it must be taken simultaneously to the air and underseas. This would be the empire's salvation. And the imaginative plan would be an achievement that would stun the world…."
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Amicalement
Armand

Those I-400 class subcarriers are fascinating.

Would have been really interesting if they'd been started earlier, so as to take down the Panama Canal at about the same time as the Pearl Harbor attack.

The ship I sailed on in the late 1960's, the submarine rescue ship USS Greenlet (ASR-10), convoyed the surrendered I-400s to Pearl Harbor after the war. I didn't realize Greenlet's hisoric role until many years later. We decommissioned the Greenlet in 1970. It was sold to Turkey, where it remained in service for nearly another three decades.

Thanks!

Amicalement
Armand

Interesting, although the notion that they could easily put the Panama Canal out of commission is probably wishful thinking. A handful of small bombers carrying a few tons of bombs or torpedoes against a huge structure like the canal would have little chance of doing crippling damage. Even their most vulnerable part, the locks, are massively constructed and yet not that easy a target.

The targets would have been the lock doors.

Yes. Not easy targets, and considering their construction, it might take a number of torpedoes to wreck them. And to do more than cause a minor inconvenience, you need to puncture the doors at both ends of the lock to get a flow from the lake.

Actually, I was just looking at the specs on the canal locks and there are multiple safety features and back-ups that would make a breaching by a few dozen planes virtually impossible. The upper end of each lock has two sets of gates 70 feet apart, so while torpedoes might pierce the first set of gates (might, the lock doors are hollow and weigh over 600 tons each), they couldn't get to the second set. Also, each lock has a set of additional gates in the center of each lock which can divide the lock into two smaller locks. Finally, there is an emergency gate at the upper end of each lock, normally kept open, which could be swung shut to stop the flow of water in an emergency.

So no, there is simply no way the few planes that the subs could carry could do more than temporary minor damage to the canal.

Still got one of those not done in 1/700 around here somewhere…