# How did the planes on submarine aircraft carriers not get destroyed by water? **URL:** \ **Category:** Factual Questions\ **Created:** [October 15, 2015, 6:22am UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706 "2015-10-15T06:22:16Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![Aeschines](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aeschines/32/16251_2.png) [@Aeschines](https://boards.straightdope.com/u/Aeschines)\ **Post date:** [October 15, 2015, 6:22am UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/1 "2015-10-15T06:22:16Z")
> **[Submarine aircraft carrier](https://en.wikipedia.org/wiki/Submarine_aircraft_carrier)** > > A submarine aircraft carrier is a submarine equipped with aircraft for observation or attack missions. These submarines saw their most extensive use during World War II, although their operational significance remained rather small. The most famous of them were the Japanese I-400-class submarines and the French submarine Surcouf, although small numbers of similar craft were built for other nations' navies as well. > Most operational submarine aircraft carriers, with the exception of the I-400 and ... I had never heard of such ships until recently. My google fu has failed me in this instance. It seems that the planes were just sitting there on the top of the submarine and would have been filled with seawater once the ship submerged. I don’t see how the plane’s engine wouldn’t have been filled with water and basically ruined–at the very least requiring extensive drying out in order to use. Any knowledge out there? ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [October 15, 2015, 6:39am UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/2 "2015-10-15T06:39:28Z")
I’ve read about some of the Japanese submarine aircraft carriers from WWII before. I’m not familiar with any of the others. On the Japanese WWII subs, they basically shoved the bridge of the sub over to one side and installed a big tube to put the aircraft in on the other side. The tube wasn’t much wider than the airplane’s fuselage, so I’m assuming they took the wings off when they shoved it into the tube. The planes were probably designed so that the wings could be attached or detached relatively quickly. ---
**Author:** ![MichaelEmouse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/michaelemouse/32/101_2.png) [@MichaelEmouse](https://boards.straightdope.com/u/MichaelEmouse)\ **Post date:** [October 15, 2015, 6:46am UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/3 "2015-10-15T06:46:35Z")
Watertight hangars. “Located approximately amidships on the top deck was a cylindrical watertight aircraft hangar, 31 m (102 ft) long and 3.5 m (11 ft) in diameter. The outer access door could be opened hydraulically from within or manually from the outside by turning a large hand-wheel connected to a rack and spur gear. The door was made waterproof with a 51-millimetre-thick (2.0 in) rubber gasket.” > **[I-400-class submarine | Design features and equipment](https://en.wikipedia.org/wiki/I-400-class_submarine#Design_features_and_equipment)** > > Each submarine had four 1,680 kW (2,250 hp) engines and carried enough fuel to go around the world one-and-a-half times—more than enough to reach the United States travelling east or west. Measuring more than 120 m (390 ft) long overall, they displaced 5,900 t (6,500 short tons), more than double their typical American contemporaries. The cross-section of its pressure hull had a unique figure-of-eight shape which afforded the necessary strength and stability to handle the weight of a large on-dec... I don’t know how much more prone submarine aircraft carriers were to accidental self-sinking than ordinary submarines of the time. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [October 15, 2015, 6:47am UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/4 "2015-10-15T06:47:23Z")
I went looking for some pics, and found this video instead. [![]( " - YouTube") ](https://www.youtube.com/watch?v=mBx2Bu-jnOs) Fast forward to about the 17 minute mark. They show the hangar, and show how the plane folded to fit into it. They didn’t take the wings off. They folded them back and folded down the fail. ---
**Author:** ![Aeschines](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aeschines/32/16251_2.png) [@Aeschines](https://boards.straightdope.com/u/Aeschines)\ **Post date:** [October 15, 2015, 7:08am UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/5 "2015-10-15T07:08:58Z")
Thanks, that video is quite informative! ---
**Author:** ![Kevbo](https://avatars.discourse-cdn.com/v4/letter/k/e47774/32.png) [@Kevbo](https://boards.straightdope.com/u/Kevbo)\ **Post date:** [October 15, 2015, 2:28pm UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/6 "2015-10-15T14:28:27Z")
These didn’t run very deep, and like most subs of the era were not so much submarines as ships that could hide briefly underwater, and maneuver a bit while down there. Also, as no personnel needed to be in the hanger while submerged, they could be pressurized to match the depth, or even a little higher to mitigate any leakage, so the construction didn’t need to be nearly as stout as the boat itself where the one atmosphere interior made implosion a real threat. ---
**Author:** ![Razncain](https://avatars.discourse-cdn.com/v4/letter/r/9d8465/32.png) [@Razncain](https://boards.straightdope.com/u/Razncain)\ **Post date:** [October 15, 2015, 6:31pm UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/7 "2015-10-15T18:31:13Z")
> [@engineer\_comp\_geek](#): > > I went looking for some pics, and found this video instead. > [https://www.youtube.com/watch?v=mBx2Bu-jnOs](https://www.youtube.com/watch?v=mBx2Bu-jnOs) > > Fast forward to about the 17 minute mark. They show the hangar, and show how the plane folded to fit into it. They didn’t take the wings off. They folded them back and folded down the fail. I did, but the whole thing looks quite good, so I’m starting over. ---
**Author:** ![ElvisL1ves](https://avatars.discourse-cdn.com/v4/letter/e/5daacb/32.png) [@ElvisL1ves](https://boards.straightdope.com/u/ElvisL1ves)\ **Post date:** [October 15, 2015, 7:50pm UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/8 "2015-10-15T19:50:18Z")
The USN’s airborne-missile launching subs, like USS Growler at the Intrepid museum in New York, were similar. The missiles were kept in a watertight hangar next to the sail. To launch, the sub would surface, open the hangar door, and slide a missile out onto a launch rail, which would then be rotated to point the jet exhaust out over the water. Push the button, off she goes, close the door, and resubmerge. ---
**Author:** ![Hail\_Ants](https://avatars.discourse-cdn.com/v4/letter/h/dc4da7/32.png) [@Hail\_Ants](https://boards.straightdope.com/u/Hail_Ants)\ **Post date:** [October 16, 2015, 6:20am UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/9 "2015-10-16T06:20:44Z")
> [@engineer\_comp\_geek](#): > > I went looking for some pics, and found this video instead. > [https://www.youtube.com/watch?v=mBx2Bu-jnOs](https://www.youtube.com/watch?v=mBx2Bu-jnOs) I believe that was an episode of the PBS series \*NOVA \*from a couple years ago. It is well worth watching the entire thing. Although initially conceived by the Japanese to attack the Panama Canal it later became apparent that submersible aircraft carriers could be used to stealthily attack ports, military bases and even major cities around the world by air (possibly using biological weapons). Essentially it was the forerunner of today’s SSBN. ---
**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\ **Post date:** [October 16, 2015, 6:47am UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/10 "2015-10-16T06:47:41Z")
Also interesting were the French “Surcouf” class subs-which had a two gun turret. It was a battleship that could submerge. but they were never used in combat. ---
**Author:** ![snowthx](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowthx/32/10660_2.png) [@snowthx](https://boards.straightdope.com/u/snowthx)\ **Post date:** [October 16, 2015, 11:41am UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/11 "2015-10-16T11:41:16Z")
I think the OP assumed the plane was attached to the outer deck, as I did. I would think these subs would be very clumsy in battle. While the plane was readied and launched, the sub would be stopped and vulnerable. They would probably need to have calm waters and winds. Even if they had the element of surprise, unless they considered sacrificing the pilot and plane, they’d again be vulnerable when retrieving the plane, folding it up, and stowing it. Even if that only took a few minutes, the sub would need to be stopped at the surface - a sitting duck. ---
**Author:** ![Hail\_Ants](https://avatars.discourse-cdn.com/v4/letter/h/dc4da7/32.png) [@Hail\_Ants](https://boards.straightdope.com/u/Hail_Ants)\ **Post date:** [October 16, 2015, 12:25pm UTC](https://boards.straightdope.com/t/how-did-the-planes-on-submarine-aircraft-carriers-not-get-destroyed-by-water/734706/12 "2015-10-16T12:25:13Z")
> [@snowthx](#): > > I think the OP assumed the plane was attached to the outer deck, as I did. > > I would think these subs would be very clumsy in battle. While the plane was readied and launched, the sub would be stopped and vulnerable. They would probably need to have calm waters and winds. Even if they had the element of surprise, unless they considered sacrificing the pilot and plane, they’d again be vulnerable when retrieving the plane, folding it up, and stowing it. Even if that only took a few minutes, the sub would need to be stopped at the surface - a sitting duck. Well, all subs in WWII were extremely vulnerable on the surface. They would probably had always surfaced and launched their planes just after dusk or before dawn. And the Japanese didn’t have them close to ready until 1945 so yes, they were going to use kamikaze planes/pilots for the attacks. But they wouldn’t have had to sail all the way back to Japan, they would have rendezvoused with a surface attack group to be rearmed with more planes & pilots. They were very much a strategic weapon, not a tactical one, just like today’s SSBNs.