1 00:00:00,520 --> 00:00:03,600 Speaker 1: Welcome to brain Stuff from house stuff works dot com 2 00:00:03,600 --> 00:00:14,560 Speaker 1: where smart happens. Hi. I'm Marshall Brain with today's question, 3 00:00:15,080 --> 00:00:19,960 Speaker 1: what is a semi submarine? So we've all seen submarines, 4 00:00:20,079 --> 00:00:23,600 Speaker 1: and almost always their military submarines, and there's a reason 5 00:00:23,640 --> 00:00:28,000 Speaker 1: for that. Submarines tend to be quite expensive. There's two 6 00:00:28,040 --> 00:00:32,600 Speaker 1: reasons why they're expensive. First, any sealed container full of 7 00:00:32,680 --> 00:00:35,559 Speaker 1: human beings presents problems. You have to deal with the 8 00:00:35,560 --> 00:00:39,320 Speaker 1: oxygen supply. You have to deal with this carbon dioxide removal, 9 00:00:39,400 --> 00:00:42,880 Speaker 1: and you have to worry about humidity from the error 10 00:00:43,400 --> 00:00:46,159 Speaker 1: that we exhale from our lungs. So it takes a 11 00:00:46,200 --> 00:00:49,400 Speaker 1: fairly precise system to keep the oxygen level at about 12 00:00:50,600 --> 00:00:52,839 Speaker 1: You have to have chemical scrubbers that remove all the 13 00:00:52,880 --> 00:00:55,000 Speaker 1: carbon dioxide, and you you need to do something with the 14 00:00:55,080 --> 00:00:58,800 Speaker 1: humidity or you get all this condensation on the inside 15 00:00:58,800 --> 00:01:02,480 Speaker 1: walls of your submarine makes a mess. The second reason 16 00:01:02,560 --> 00:01:05,720 Speaker 1: why submarines tend to be expensive is that when you 17 00:01:05,880 --> 00:01:10,000 Speaker 1: stick that sealed container underwater in the form of a submarine, 18 00:01:10,319 --> 00:01:14,160 Speaker 1: the problems multiply. You have to deal with water pressure now, 19 00:01:14,560 --> 00:01:17,759 Speaker 1: so the container, including its windows, has to be strong 20 00:01:17,880 --> 00:01:20,880 Speaker 1: enough to handle depth and it doesn't take much depth 21 00:01:20,959 --> 00:01:23,679 Speaker 1: to create a lot of water pressure, and then you 22 00:01:23,760 --> 00:01:27,120 Speaker 1: also have to worry about how you're gonna dive and surface, 23 00:01:27,200 --> 00:01:29,679 Speaker 1: So you have to have ballast tanks, and you have 24 00:01:29,760 --> 00:01:31,720 Speaker 1: to be able to fill those tanks with water or 25 00:01:31,760 --> 00:01:34,200 Speaker 1: blow the water out of them. And you have to 26 00:01:34,200 --> 00:01:38,160 Speaker 1: make your container completely leak free, obviously, and that's not 27 00:01:38,280 --> 00:01:40,880 Speaker 1: a simple thing, especially if you're gonna put windows in it, 28 00:01:40,920 --> 00:01:43,360 Speaker 1: and that's why a lot of military submarines don't have 29 00:01:43,400 --> 00:01:47,160 Speaker 1: any windows at all. So what's the solution. What if 30 00:01:47,160 --> 00:01:49,880 Speaker 1: you would like to create a submarine, but you'd like 31 00:01:49,960 --> 00:01:52,760 Speaker 1: the lower the costs so that normal people can afford them, 32 00:01:53,320 --> 00:01:55,520 Speaker 1: One thing you could do is you could eliminate the 33 00:01:55,720 --> 00:01:59,480 Speaker 1: sealed part of the container. Second, you could eliminate the 34 00:01:59,560 --> 00:02:03,200 Speaker 1: problems with pressure by controlling how deep your submarine can 35 00:02:03,240 --> 00:02:06,720 Speaker 1: go and keeping it really shallow. And third, you could 36 00:02:06,760 --> 00:02:09,480 Speaker 1: eliminate the need for diving and surfacing, and therefore you 37 00:02:09,480 --> 00:02:11,600 Speaker 1: can get rid of all the ballast tanks and blowing 38 00:02:11,639 --> 00:02:13,560 Speaker 1: the tanks and everything that has to go with that. 39 00:02:14,320 --> 00:02:17,440 Speaker 1: Almost all the problems go away if you start putting 40 00:02:17,480 --> 00:02:20,680 Speaker 1: these constraints on your submarine. And that's the idea behind 41 00:02:20,919 --> 00:02:26,079 Speaker 1: a semi submarine. A semi submarine lets you, as a passenger, 42 00:02:26,440 --> 00:02:31,079 Speaker 1: ride around underwater, but the depth is very limited. It 43 00:02:31,160 --> 00:02:35,160 Speaker 1: might be six feet at most, and the submerged part 44 00:02:35,160 --> 00:02:37,960 Speaker 1: of the submarine remains open to the air above, so 45 00:02:38,000 --> 00:02:41,040 Speaker 1: you don't have to worry about pressurizing the container or 46 00:02:41,600 --> 00:02:44,080 Speaker 1: keeping the leaks out like you do with a submarine 47 00:02:44,080 --> 00:02:46,720 Speaker 1: that goes down a hundred feet. So here's one way 48 00:02:46,720 --> 00:02:49,560 Speaker 1: to think about a semi submarine. Think about creating a 49 00:02:49,680 --> 00:02:52,880 Speaker 1: small room. Say the size of a closet. It might be, 50 00:02:53,320 --> 00:02:55,800 Speaker 1: you know, four by four ft or four by six 51 00:02:55,840 --> 00:02:58,800 Speaker 1: ft or six by six feet in size, and it 52 00:02:58,919 --> 00:03:01,360 Speaker 1: might be six x or eight feet tall, just like 53 00:03:01,400 --> 00:03:04,280 Speaker 1: a normal closet in your house might be. You make 54 00:03:04,320 --> 00:03:08,040 Speaker 1: that closet out of a sealed container, either out of 55 00:03:08,040 --> 00:03:11,359 Speaker 1: fiberglass or out of steel, and you put great big 56 00:03:11,400 --> 00:03:13,720 Speaker 1: windows in it so that you can see out. Those 57 00:03:13,760 --> 00:03:17,239 Speaker 1: windows don't have to be exceedingly thick, because they're never 58 00:03:17,280 --> 00:03:20,519 Speaker 1: gonna be much more than six or eight feet underwater, 59 00:03:20,639 --> 00:03:22,359 Speaker 1: So you might make them an inch or an inch 60 00:03:22,400 --> 00:03:24,560 Speaker 1: and a half thick if their glass maybe about the 61 00:03:24,560 --> 00:03:27,079 Speaker 1: same if they're made out of acrylic. Now you put 62 00:03:27,080 --> 00:03:29,720 Speaker 1: a couple of comfy chairs in this closet so you 63 00:03:29,720 --> 00:03:32,680 Speaker 1: can sit and look out the windows. And now you 64 00:03:32,760 --> 00:03:35,760 Speaker 1: just have to get this closet submerged in the water 65 00:03:35,880 --> 00:03:38,960 Speaker 1: so that it's underwater but won't sink. And the most 66 00:03:39,000 --> 00:03:41,000 Speaker 1: common way to do that is to put some kind 67 00:03:41,000 --> 00:03:44,800 Speaker 1: of pontoons on top of the closet that will keep 68 00:03:44,840 --> 00:03:46,880 Speaker 1: the top of the closet up out of the water. 69 00:03:47,560 --> 00:03:52,160 Speaker 1: That is the basic configuration for some semi submarines. And 70 00:03:52,160 --> 00:03:54,280 Speaker 1: then you put a couple of electric motors on them, 71 00:03:54,360 --> 00:03:57,280 Speaker 1: or a little um gasoline motor or something so that 72 00:03:57,320 --> 00:03:59,480 Speaker 1: you can move it around through the water. And if 73 00:03:59,520 --> 00:04:03,600 Speaker 1: you're in a nice clear water, say around a coral reef, 74 00:04:03,720 --> 00:04:09,080 Speaker 1: you can paddle around with this with this floating closet underwater, 75 00:04:09,360 --> 00:04:12,400 Speaker 1: and you can see all kinds of stuff because the 76 00:04:12,440 --> 00:04:14,400 Speaker 1: water is nice and clear. You can look and see 77 00:04:14,440 --> 00:04:16,760 Speaker 1: the reef, you can see the fish swimming around the reef, 78 00:04:16,800 --> 00:04:20,559 Speaker 1: and so on. Without ever getting wet, and without ever 79 00:04:20,680 --> 00:04:24,080 Speaker 1: having to worry about scuba equipment or snorkels or anything 80 00:04:24,160 --> 00:04:26,680 Speaker 1: like that. You simply sit in your comfy chair, you 81 00:04:26,680 --> 00:04:29,920 Speaker 1: look out the window, and you steer the boat around 82 00:04:30,080 --> 00:04:35,000 Speaker 1: with some simple steering mechanism. Typically you find semi submarines 83 00:04:35,160 --> 00:04:38,279 Speaker 1: in resort areas. So if you go to Hawaii, for example, 84 00:04:38,320 --> 00:04:41,320 Speaker 1: you can find semi submarines that hold thirty or fifty 85 00:04:41,360 --> 00:04:45,040 Speaker 1: people and you go down below and you're about six 86 00:04:45,120 --> 00:04:48,040 Speaker 1: or seven feet underwater, sitting on a bench or a 87 00:04:48,120 --> 00:04:50,760 Speaker 1: chair looking out great big glass windows that are an 88 00:04:50,800 --> 00:04:54,159 Speaker 1: inch and a half thick. Or you can go to 89 00:04:54,320 --> 00:04:58,000 Speaker 1: resort areas and find little two persons semi submarines that 90 00:04:58,080 --> 00:05:01,320 Speaker 1: you can tool around with on your own. Semi submarines 91 00:05:01,400 --> 00:05:04,279 Speaker 1: were invented in the nineteen nineties and they've been pretty 92 00:05:04,320 --> 00:05:07,760 Speaker 1: popular since their invention. They're popular anywhere where you would 93 00:05:07,760 --> 00:05:13,080 Speaker 1: find things like glass bottomed boats. Be sure to check 94 00:05:13,120 --> 00:05:16,240 Speaker 1: out our new video podcast, Stuff from the Future. Join 95 00:05:16,320 --> 00:05:18,960 Speaker 1: how Stuffork's staff as we explore the most promising and 96 00:05:19,080 --> 00:05:24,719 Speaker 1: perplexing possibilities of tomorrow. The hau Steffork's iPhone app has arrived. 97 00:05:24,839 --> 00:05:26,760 Speaker 1: Download it today on iTunes.