1 00:00:00,000 --> 00:00:02,000 I 2 00:01:00,000 --> 00:01:18,040 You ready for the explosion special, maybe you can give me a minute. Ah you big baby 3 00:01:30,000 --> 00:01:46,400 Jamie when we're all done making mythbusters, how would you like us to be remembered? 4 00:01:46,400 --> 00:01:53,040 How about for our promotion of critical thought and how do you think we will be remembered for blowing crap up? 5 00:01:53,040 --> 00:01:59,060 Yep, that is why and this our final season. We're devoting an entire episode to an explosion special 6 00:01:59,060 --> 00:02:05,020 What's on the docket? Well, we are finally going to tackle an explosive. We have never had any experience with before 7 00:02:05,860 --> 00:02:07,860 Landmines like this 8 00:02:09,560 --> 00:02:17,440 But first we have a new twist on perhaps mythbusters most favorite and famous explosion that would be the cement truck 9 00:02:18,380 --> 00:02:24,500 Yes, it would and it stars our favorite fictional honorary mythbuster Angus MacGyver. Let me set you the scene 10 00:02:25,380 --> 00:02:30,140 A mail truck has been fitted with a bomb full of dynamite keep it coming 11 00:02:30,580 --> 00:02:35,380 MacGyver brings a cement truck over to the mail truck and starts filling it with wet concrete 12 00:02:36,540 --> 00:02:38,940 When he gets it above the bomb the bomb goes off 13 00:02:40,820 --> 00:02:45,080 The cement seems to prevent the bomb from causing any real damage it worked 14 00:02:45,740 --> 00:02:50,260 I honestly don't know what would actually happen which makes it a perfect myth for us to test 15 00:02:50,940 --> 00:02:52,000 three 16 00:02:52,000 --> 00:02:58,680 When it comes to countdown to the mythbusters one have an explosive 14-year history 17 00:03:01,680 --> 00:03:04,680 And to sign off their final season in style 18 00:03:06,680 --> 00:03:12,360 They're putting a MacGyver spin on an old mythbusters favorite 19 00:03:16,960 --> 00:03:21,440 To get things rolling the team to cab to a much loved location 20 00:03:22,040 --> 00:03:26,800 If you're gonna blow something up and you need more than just a few pounds of explosives to do it 21 00:03:27,080 --> 00:03:33,000 Generally the neighbors don't like it and that's why we've come to one of our favorite places to blow large things up 22 00:03:33,320 --> 00:03:35,040 I own California 23 00:03:35,040 --> 00:03:37,040 That seems about right 24 00:03:39,040 --> 00:03:45,840 Our plan today is pretty straightforward we're going to be detonating two mail trucks why two mail trucks well one 25 00:03:45,840 --> 00:03:49,720 Obviously will be full of wet cement, but their first class will be empty. Yes 26 00:03:49,960 --> 00:03:54,560 The mythbusters postal service the Skeletal Bird with dynamite in his talents 27 00:03:55,840 --> 00:04:01,920 Why are we detonating an empty mail truck? Well, that's because we can't know if MacGyver's actions had any effect on the blast 28 00:04:01,920 --> 00:04:05,000 Unless we have something to compare it to that's our control 29 00:04:05,520 --> 00:04:10,120 For scent dressing the carb car that MacGyver hides behind is dropped into place 30 00:04:10,240 --> 00:04:14,280 But the key to this myth is the mail trucks explosive cargo 31 00:04:15,280 --> 00:04:19,600 By looking at the clip we've determined that they used about 84 pounds of dynamite 32 00:04:19,760 --> 00:04:27,040 Now this right here may look a little bit more festive, but this is actually what 84 pounds of dynamite looks like 33 00:04:28,000 --> 00:04:34,780 To quantify and compare the damage between the control and the concrete blasts. They'll measure two parameters 34 00:04:35,680 --> 00:04:40,640 First the shrapnel we want to know how dangerous the shrapnel might be so we are implementing 35 00:04:41,560 --> 00:04:47,800 Shrapnel catchers we have cut out a ton of plywood dudes that we are going to place on a 30 foot radius 36 00:04:48,160 --> 00:04:54,120 Between us and the blasts so that we can see if chunks of metal fly off. Well, it kills someone standing that far away 37 00:04:56,120 --> 00:04:58,120 Let's mull it up 38 00:05:01,080 --> 00:05:04,680 Well, it's universally agreed that MacGyver brought 39 00:05:05,800 --> 00:05:11,280 Ingenuity and cool problem-solving and network television. It's not often discussed what he's done for the mullet 40 00:05:12,440 --> 00:05:14,200 business in the front 41 00:05:14,200 --> 00:05:15,880 party in the real 42 00:05:15,880 --> 00:05:18,240 The second parameter is the pressure wave 43 00:05:18,440 --> 00:05:23,960 We'll be gathering precise data on the strength of our blasts using one of these this is a pressure transducer 44 00:05:23,960 --> 00:05:29,280 Our blasts obviously will put out a tremendous amount of energy most of it in the form of a blast pressure wave 45 00:05:29,280 --> 00:05:32,120 That way we'll meet our pressure transducer 46 00:05:32,120 --> 00:05:39,000 It'll exert a little mechanical energy on a tiny crystal inside the transducer called a piezo when we hook it up to a computer 47 00:05:39,000 --> 00:05:45,040 It gives us exactly how strong the blast pressure wave was where that pressure transducer was placed 48 00:05:45,480 --> 00:05:52,360 Having all three of these data points for both blasts ought to give us a really good picture to see if MacGyver cement made a difference 49 00:05:52,360 --> 00:05:54,660 Between the control and the cement blast 50 00:05:58,720 --> 00:06:02,800 Mr. Heidemann you ready? Okay arming and ready 51 00:06:03,840 --> 00:06:10,240 This is MacGyver control empty postal van 84 pounds of TNT in three 52 00:06:11,760 --> 00:06:13,520 two 53 00:06:13,520 --> 00:06:15,020 one 54 00:06:15,020 --> 00:06:17,020 two 55 00:06:18,020 --> 00:06:20,020 Boo 56 00:06:24,100 --> 00:06:31,260 That I think there's still some stuff flying through the air. Yeah, nobody go outside yet. No what goes up comes down 57 00:06:37,780 --> 00:06:39,780 Yep, you've got hail 58 00:06:39,780 --> 00:06:41,780 a 59 00:06:42,300 --> 00:06:44,300 Hail of metal shrapnel 60 00:06:44,580 --> 00:06:50,660 Look the eagle has landed and plywood shrapnel catchers that's gotta hurt 61 00:06:53,020 --> 00:06:55,300 It's pure carnage for our 62 00:06:57,300 --> 00:06:59,820 Legs and hands and mullets everywhere 63 00:06:59,820 --> 00:07:13,060 The blast was significantly more powerful than expected at 30 feet the shrapnel damage was clearly catastrophic 64 00:07:13,660 --> 00:07:15,660 But what about the pressure sensors? Oh? 65 00:07:18,660 --> 00:07:23,780 It looks like all three of the sensors we had out here are totally busted 66 00:07:24,700 --> 00:07:28,340 with the cables for the pressure transducers shredded even at 67 00:07:28,940 --> 00:07:34,020 250 feet they have no control data and the next step will take some figuring out 68 00:07:34,740 --> 00:07:39,900 So it's on to story to where the guys are breaking new ground by going underground 69 00:07:40,700 --> 00:07:45,980 So landmines yep the myth is if you want to cross a minefield and you want to do it safely 70 00:07:45,980 --> 00:07:49,540 Which I assume you do the vehicle of choice is a hovercraft 71 00:07:50,060 --> 00:07:55,260 And that would be because the hovercraft doesn't set them off. That's the myth. That's what I think we should test 72 00:07:55,340 --> 00:07:59,900 You know, I don't think I've ever driven a hovercraft especially over a minefield 73 00:08:02,260 --> 00:08:04,260 This is a story of firsts 74 00:08:05,700 --> 00:08:10,200 Over the years the team has tackled every conceivable explosive tech 75 00:08:12,260 --> 00:08:14,500 Except one landmines 76 00:08:18,020 --> 00:08:23,060 But first this story's other first the state of the art craft in question 77 00:08:26,260 --> 00:08:30,380 Supposedly a hovercraft is perfect for safely traversing a minefield 78 00:08:31,020 --> 00:08:34,420 Because it evenly distributes its weight on a cushion of air 79 00:08:36,620 --> 00:08:40,540 To find out the truth our novice riders require lessons 80 00:08:40,540 --> 00:08:46,380 We got the left and the right steering and we have the throttle that provides both the lift and the thrust 81 00:08:55,900 --> 00:08:58,620 Once in the driver's seat Adam discovers 82 00:09:00,220 --> 00:09:02,580 It's surprisingly easy to handle 83 00:09:04,980 --> 00:09:06,980 These haven't way too much fun 84 00:09:07,260 --> 00:09:12,200 Yep, and they're also starting to get a feel for how 600 pounds of man and machine 85 00:09:12,820 --> 00:09:16,620 Could possibly power through a minefield without mishap 86 00:09:19,180 --> 00:09:24,860 Well, they're basically boats that float on a cushion of air and that cushion of air is retained underneath the boat 87 00:09:24,900 --> 00:09:29,420 By a flexible skirt and there's an engine that's pumping air down into that skirt 88 00:09:37,740 --> 00:09:45,620 That same fan and engine though are also pushing air out the back through these fins and that provides it with propulsion and steering 89 00:09:45,620 --> 00:10:00,340 As far as operating this thing in a minefield, I think this is gonna be kind of like operating a boat in a marina. I 90 00:10:02,380 --> 00:10:06,060 Think it can be done, but you have to plan ahead that's gonna be the key 91 00:10:09,020 --> 00:10:12,580 That's my friends is the sound of Jamie Hahneman being enthusiastic 92 00:10:15,660 --> 00:10:21,220 Well, I don't know about you, but I feel ready to drive this across the minefield. Let's go make a minefield. Let's do it 93 00:10:23,540 --> 00:10:25,540 Coming up on mythbusters 94 00:10:26,220 --> 00:10:28,220 This explosive 95 00:10:30,980 --> 00:10:32,980 Final season spectacular 96 00:10:35,780 --> 00:10:42,460 Turns back the clock hey welcome 1987 and tests the team's limits. Whoo. All right 97 00:10:42,820 --> 00:10:44,820 Of acrobatic ingenuity 98 00:10:54,980 --> 00:10:56,980 Back at the beginning go 99 00:10:58,260 --> 00:11:03,220 That is not enough to blast somebody off the seat the big booms weren't so big 100 00:11:06,620 --> 00:11:08,620 Or 101 00:11:09,860 --> 00:11:11,860 Often didn't go according to plan 102 00:11:13,100 --> 00:11:20,020 Is my missing an eyebrow over a decade later 103 00:11:21,620 --> 00:11:24,540 And the mythbusters have up the explosive anti 104 00:11:25,420 --> 00:11:26,700 and 105 00:11:26,700 --> 00:11:29,940 covered every combination of tech and target 106 00:11:32,780 --> 00:11:34,780 Except one 107 00:11:35,060 --> 00:11:40,500 Landmines and the myth that a minefield can be crossed by hovercraft 108 00:11:40,620 --> 00:11:47,260 How they go about testing one of the world's deadliest military devices is a tricky task 109 00:11:48,300 --> 00:11:50,300 PVC tubing 110 00:11:51,380 --> 00:11:58,980 We obviously need mines to conduct our test and out of this I will produce a set of artificial mines 111 00:11:59,620 --> 00:12:01,620 Now they won't blow up 112 00:12:01,820 --> 00:12:04,660 But that's only half of what a mine does the other thing it does is 113 00:12:04,980 --> 00:12:12,100 Register a certain amount of pressure in order to tell it to blow a mine is really effectively a scale a scale that says blow up when a 114 00:12:12,180 --> 00:12:14,180 Person steps on it like 150 pounds 115 00:12:15,780 --> 00:12:22,620 Or a truck 700 pounds and the soul of our fake minds will be this little metal button 116 00:12:22,620 --> 00:12:30,060 This is in fact a pressure transducer and it will allow my fake minds to behave just like the real thing in every way 117 00:12:30,420 --> 00:12:31,860 except for explosives 118 00:12:31,900 --> 00:12:35,460 While Adam makes the housing for the programmable pressure trigger 119 00:12:37,980 --> 00:12:44,860 Jamie replaces the C4 with an air powered mortar designed to give off a safe movie effect blast 120 00:12:45,900 --> 00:12:52,380 That right there is the tank and we'll have a funnel on the end of it filled with stuff that's gonna get shot up in the air 121 00:12:53,620 --> 00:12:58,740 Pretty simple and straightforward. We step on the landmine and off she goes go boom 122 00:12:59,060 --> 00:13:04,380 Right with Jamie's mortar assembled and loaded with fake rubble. It's ready for a demo 123 00:13:10,100 --> 00:13:12,100 That's great looks pretty good to me 124 00:13:14,620 --> 00:13:21,060 That's the film effect explosion back inside Adam has a prototype of the pressure pad ready for demo 125 00:13:21,580 --> 00:13:24,780 So here is the function of our mine 126 00:13:24,980 --> 00:13:31,400 We've got the body that is the casing and we've got our pressure rod here and down at the bottom 127 00:13:31,400 --> 00:13:36,220 Is that little pressure transducer screwed into the bottom of our ABS pipe cap and? 128 00:13:36,980 --> 00:13:38,980 That will work just like a real thing 129 00:13:40,460 --> 00:13:45,460 So while the team mass produces 20 accurate and programmable landmines 130 00:13:47,100 --> 00:13:49,100 It's back to the MacGyver myth 131 00:13:49,580 --> 00:13:52,540 Adam and Jamie want to know if this cement solution is 132 00:13:53,300 --> 00:13:55,300 cinematically scientific 133 00:13:56,060 --> 00:13:58,600 Or a made for TV tall tail 134 00:14:11,220 --> 00:14:14,540 So far the control blast didn't exactly go to plan 135 00:14:15,140 --> 00:14:22,620 Well, we like to say failure is always an option and it has to be because we had a total failure of our pressure transducer system 136 00:14:24,700 --> 00:14:27,620 But we do have a plan B 137 00:14:28,700 --> 00:14:34,780 Yep, we're gonna focus on the physical evidence our cutouts tells the shrapnel was catastrophic at 30 feet 138 00:14:36,140 --> 00:14:42,900 But we can also compare the strength of the control to the concrete covered blast by measuring how far the shrapnel flow 139 00:14:42,900 --> 00:14:46,580 That's a heavy thing and it shot it about 150 feet 140 00:14:48,100 --> 00:14:50,740 First we marked out the more sizable pieces on foot 141 00:14:51,260 --> 00:14:55,620 That's got to be one of the farthest chunks and then we get the big picture by air 142 00:14:55,860 --> 00:15:02,420 This right here is the newest piece of amazing camera equipment that myth busters has brought to bear on shooting our episodes over the past 143 00:15:02,420 --> 00:15:05,860 Couple of years. This is called a DJI inspire one 144 00:15:06,420 --> 00:15:11,060 And we use the inspire to witness our entire debris field in one shot 145 00:15:11,780 --> 00:15:17,540 Yep from this birds eye view the debris field can be mapped at a maximum radius of 146 00:15:18,500 --> 00:15:20,500 675 feet 147 00:15:21,700 --> 00:15:24,820 That stat replacing the pressure transducer data 148 00:15:27,460 --> 00:15:29,460 Qtruck number two 149 00:15:33,180 --> 00:15:35,740 This is our 84 pounds of dynamite and 150 00:15:35,980 --> 00:15:41,100 The reason I'm locking all this stuff down is that this stuff is lighter than concrete and it might float 151 00:15:41,980 --> 00:15:46,140 Now wait these detonation cords and things like that won't come out. Hopefully 152 00:15:46,860 --> 00:15:49,020 Similar to the shelves in the original clip 153 00:15:49,420 --> 00:15:53,500 Janie's placed one bundle of dynamite down low and one up top 154 00:15:54,460 --> 00:15:59,660 And screwing them to the wooden frame should prevent them from floating free when the concrete flows 155 00:15:59,980 --> 00:16:05,180 Meaning it's time for man of the moment. How you doing? 156 00:16:07,420 --> 00:16:09,420 MacGyver 157 00:16:10,940 --> 00:16:12,940 I like this one maybe I'm gonna try it out 158 00:16:13,580 --> 00:16:17,820 Our mulleted hero springs into action and perfect right there 159 00:16:18,780 --> 00:16:25,980 Matching the clip he directs the dump truck to unload eight cubic yards or 32 000 pounds of wet cement 160 00:16:27,660 --> 00:16:29,500 It's coming out 161 00:16:30,380 --> 00:16:32,780 It looks kind of like a cow taking a dump 162 00:16:37,420 --> 00:16:40,620 It really does look like a cow taking a dump and I've never even seen that 163 00:16:41,980 --> 00:16:47,900 Wow, it'll take 30 minutes to fill her up, but there's a problem kill it. What's up? 164 00:16:50,300 --> 00:16:55,340 Look at the uh back of explosives that came out from under the table 165 00:16:56,220 --> 00:16:57,820 Oh 166 00:16:57,820 --> 00:17:00,300 Despite jamie's precautions. What do we do? 167 00:17:01,580 --> 00:17:07,420 What can we do 40 odd pounds of prime to explode dynamite is dangerously detached 168 00:17:08,380 --> 00:17:10,860 It has to be secured and fast 169 00:17:11,580 --> 00:17:13,820 We can cut a bigger hole and crawl through this 170 00:17:15,980 --> 00:17:18,940 Ironically they've got a MacGyver the situation 171 00:17:20,060 --> 00:17:23,900 With the cement already 12 inches deep they can't go through the doors 172 00:17:24,300 --> 00:17:27,740 I'm sorry, I'm gonna have to take off the MacGyver 173 00:17:29,580 --> 00:17:36,380 The cement is rapidly setting the sun is heating the truck interior to a stifling 150 degrees 174 00:17:37,820 --> 00:17:42,140 And there's an unexploded bomb to be manhandled. All right, I'm in 175 00:17:45,980 --> 00:17:47,980 Oh 176 00:17:49,020 --> 00:17:51,900 All in a dangerous day's work for the myth busters 177 00:17:52,700 --> 00:17:56,300 All right, I just remember this is 40 some odd pounds of tnt 178 00:17:57,020 --> 00:17:59,020 Gonna handle it gently 179 00:17:59,340 --> 00:18:01,420 All right to make sure they match the clip 180 00:18:02,380 --> 00:18:03,340 Thank you 181 00:18:03,340 --> 00:18:06,300 The loose bag has to be submerged under the concrete 182 00:18:07,020 --> 00:18:11,500 So adam boxes it in and with some two by four screws it down 183 00:18:12,460 --> 00:18:14,460 Yeah, you aren't going anywhere 184 00:18:14,540 --> 00:18:18,380 Before escaping with a brand new pair of concrete boots 185 00:18:22,140 --> 00:18:24,140 Oh 186 00:18:24,460 --> 00:18:26,460 Yes 187 00:18:28,140 --> 00:18:30,140 Yes 188 00:18:30,220 --> 00:18:32,220 Nice work Houdini. Thank you 189 00:18:33,020 --> 00:18:36,940 How to escape upside down out of a container full of concrete and explosive 190 00:18:37,900 --> 00:18:44,940 And with that let's clear the area. Let's start pumping MacGyver is back on track to save the day or is he 191 00:18:45,580 --> 00:18:51,100 This is a new problem like we needed more it might be pushing out the sides of our truck and leaking out 192 00:18:52,860 --> 00:18:58,860 32 000 pounds that's 16 tons. I guess is that's more than this truck was built to take 193 00:18:59,660 --> 00:19:01,420 Wow 194 00:19:01,420 --> 00:19:03,420 That is a lot of pressure on those doors 195 00:19:04,060 --> 00:19:05,340 It's a lot of mail 196 00:19:05,340 --> 00:19:11,980 In the clip the truck wasn't affected by the extra weight, but in real life. It's only just holding together 197 00:19:12,220 --> 00:19:15,820 Let's kill it. The team has to move fast before it fails 198 00:19:16,860 --> 00:19:18,860 So where we are right now is that we have just 199 00:19:19,260 --> 00:19:25,660 Just just covered the bomb with concrete and we are working very hard to as the bomb techs would say de-ask the area 200 00:19:26,140 --> 00:19:29,420 Trying to get all the equipment out then we'll get all the people back to the bunker. Then we're gonna blow this 201 00:19:41,820 --> 00:19:44,780 Hey welcome to 1987 here's the problem 202 00:19:45,660 --> 00:19:49,820 MacGyver is confronted with an 84 pound bomb keep it coming 203 00:19:50,460 --> 00:19:54,300 He convinces a local cement mixer to back up to the mail truck and fill it full of cement 204 00:19:59,020 --> 00:20:01,020 The question we want to answer is 205 00:20:01,660 --> 00:20:07,340 You ready to do this? Would his cement have made any difference? Are you ready? I'm totally ready 206 00:20:08,300 --> 00:20:14,460 In the clip it looks like almost nothing happens at all. Okay wet concrete explosion in 207 00:20:15,100 --> 00:20:20,220 Three like there's a boom and the truck jumps. There's a little fire and that's it two 208 00:20:21,020 --> 00:20:23,580 That would be the most ideal outcome one 209 00:20:27,020 --> 00:20:29,020 Wow 210 00:20:32,780 --> 00:20:36,300 That totally went up and all the dummies are standing 211 00:20:42,060 --> 00:20:44,060 It worked 212 00:20:45,740 --> 00:20:48,060 That were gang blusters it did 213 00:20:49,180 --> 00:20:55,260 It's an astonishing result as per the clip the explosion was almost completely smothered 214 00:20:56,620 --> 00:20:59,420 That is amazing. I'm completely blown away 215 00:21:00,620 --> 00:21:04,060 Let's face it some of the stuff we've seen on MacGyver is downright silly 216 00:21:05,020 --> 00:21:13,420 but this one turned out to be actually darned impressive because you know it looks exactly like what we saw in the clip 217 00:21:13,740 --> 00:21:20,300 Most of it appears to have been absorbed by the mass of the concrete it it just absorbed it 218 00:21:21,820 --> 00:21:27,340 This is our debris field. It's one big thing a darned effective technique. I never would have thought it 219 00:21:28,380 --> 00:21:31,980 After inspecting the onlookers the news keeps on getting better 220 00:21:32,860 --> 00:21:39,420 Well, I'm standing here with our shrapnel catchers and what you might notice is there's a great difference between them for this blast and the previous one 221 00:21:39,580 --> 00:21:48,380 Yep, every single one of them is still standing. That was incredible 222 00:21:49,980 --> 00:21:53,100 Maybe the most surprising result we've had in a long time 223 00:21:54,140 --> 00:21:55,740 but 224 00:21:55,740 --> 00:22:00,300 Oh shoot a couple of unexploded sticks of tnt there 225 00:22:00,860 --> 00:22:08,780 Cancel the cake and put the confirmed party on hold a closer look reveals the mutant explosion was down to a misfire 226 00:22:09,020 --> 00:22:14,220 Not MacGyver it seems the concrete dislodged the detonation cord from the dynamite 227 00:22:14,540 --> 00:22:19,900 Remember how I said that failure is always an option. It is starting to feel like the only option 228 00:22:21,420 --> 00:22:27,980 We found a garbage bag full of unexploded dynamite and then Jamie like a surgeon used a forklift to peel the front 229 00:22:28,460 --> 00:22:30,460 off of this mail van 230 00:22:30,540 --> 00:22:32,540 Stop stop 231 00:22:32,620 --> 00:22:36,860 And that's when we found another garbage bag full of unexploded dynamite 232 00:22:37,740 --> 00:22:39,740 Is that the other bag? Yep 233 00:22:40,300 --> 00:22:46,940 Our best guess is that we detonated two sticks of dynamite. That's not the blast we were looking for so 234 00:22:47,580 --> 00:22:50,540 Here's what we've got to do. We have to come up with a methodology for making 235 00:22:51,260 --> 00:22:56,220 Absolutely sure that dynamite goes off when it's under the cement once we have that methodology worked out 236 00:22:56,220 --> 00:22:57,980 We are going to implement it 237 00:22:57,980 --> 00:23:02,860 Bring back in a cement truck fill another mail truck with cement and try this for real 238 00:23:03,660 --> 00:23:07,020 Come on up on mythbusters. We test deja vu all over again 239 00:23:09,180 --> 00:23:11,980 While the guys get set to fix their MacGyver missteps 240 00:23:12,620 --> 00:23:17,180 Over at Alameda, it's time to lay the minefield for their hovercraft to cross 241 00:23:17,980 --> 00:23:22,220 So we've chosen a minefield that is about 50 feet long and about eight feet wide 242 00:23:22,780 --> 00:23:26,940 This is not testing whether we can invade these mines. This is testing 243 00:23:27,420 --> 00:23:30,460 What happens when we go over them with the hovercraft? 244 00:23:30,780 --> 00:23:36,780 So we feel that this configuration should guarantee we're going to do that every three feet. Okay, there you go 245 00:23:37,660 --> 00:23:44,460 Yep, this deadly dollar sign design will ensure that when the hovercraft crosses it'll hit most of the mines 246 00:23:48,380 --> 00:23:50,380 Now can janey dig it? 247 00:23:54,380 --> 00:23:56,380 Yes, he can 248 00:23:57,340 --> 00:24:00,700 Nothing makes the Heinemann happier than the right tool for the job 249 00:24:02,300 --> 00:24:04,300 Beautiful 250 00:24:04,780 --> 00:24:09,020 Now you may be wondering why we're doing all of this digging. That is a beautiful machine 251 00:24:09,580 --> 00:24:15,820 Because mines usually just put them in and they're sitting there waiting to release their horror upon the world 252 00:24:16,300 --> 00:24:18,860 Our mines are not autonomous mines, right? 253 00:24:18,860 --> 00:24:25,020 Because we actually have to wire them up to a system allowing them to be switches for our air mortars. So 254 00:24:25,820 --> 00:24:28,860 Allow me to introduce you to our mines. Yes 255 00:24:29,660 --> 00:24:34,300 Remember me building this in the shop. Well now it's got a paint job and a title and 256 00:24:34,940 --> 00:24:39,580 A wiring bus so that we can wire these mines to our central system 257 00:24:39,900 --> 00:24:43,660 Which will allow us to adjust the pressures they go off at and set off our mortars 258 00:24:45,100 --> 00:24:49,740 And while janey spends the day digging the trenches for the 20 mortars and mines 259 00:24:51,340 --> 00:24:53,340 Adam 260 00:24:55,340 --> 00:24:57,340 Decides to test drive the hovercraft 261 00:25:00,140 --> 00:25:02,140 One or two 262 00:25:03,740 --> 00:25:07,660 Or six or seven more times 263 00:25:14,140 --> 00:25:19,660 I keep waiting for janey to come on over and go stop screwing around i'm doing all this digging 264 00:25:19,740 --> 00:25:23,420 It's time to get to work. I'll be like i am working walrus 265 00:25:25,020 --> 00:25:30,940 Hovercraft high jinx aside laying this high tech minefield is a mammoth two-day undertaking 266 00:25:37,340 --> 00:25:40,940 I have to tell you this is one of the more complicated builds we have ever embarked upon 267 00:25:41,020 --> 00:25:44,860 We've spent a couple of days now digging pressurizing mining 268 00:25:44,940 --> 00:25:50,620 Mordering wiring and testing all to what end to build a functional yet non-lethal 269 00:25:50,700 --> 00:25:54,380 Minefield we can test with and the most important part of this minefield is this 270 00:25:54,860 --> 00:25:58,780 The mines they are activated by a small pressure transducer that acts like a scale 271 00:25:58,860 --> 00:26:06,540 And we can have it set off the mine at whatever pressure we decide and when they're activated these fancy mortars that we bury go poo 272 00:26:08,220 --> 00:26:12,940 At the beating heart of this operation the thing that joins all of our mines and all of our mortars together 273 00:26:12,940 --> 00:26:19,100 It makes them functional is about a half mile of cat five cable all terminating here in this rats nest 274 00:26:19,260 --> 00:26:23,580 Which our honorary myth buster and electronics and metering specialist david hearting claims 275 00:26:23,980 --> 00:26:27,820 Will allow us to adjust our minds to be set off by any pressure that we choose 276 00:26:28,380 --> 00:26:31,340 And to find out if their complicated setup is working 277 00:26:31,740 --> 00:26:36,700 They're first testing it on foot cue the designated dead man walking 278 00:26:37,340 --> 00:26:41,100 Now I could just walk out there and step on one, but where's the fun in that? 279 00:26:41,420 --> 00:26:46,780 I'm going to walk this minefield blindfolded while being guided to doom by mr. Heineman 280 00:26:47,260 --> 00:26:49,260 Don't worry. I'll watch your step 281 00:26:55,100 --> 00:27:00,380 All right, okay david armed the system system is armed 282 00:27:01,820 --> 00:27:07,340 From the control center each mine is calibrated to go boom at 35 pounds of pressure 283 00:27:07,900 --> 00:27:13,180 One light step and adam will field a full force of a movie effect explosion 284 00:27:14,140 --> 00:27:16,140 This is weird 285 00:27:16,940 --> 00:27:19,660 I gotta say I uh know this is totally safe 286 00:27:20,220 --> 00:27:26,300 Commencing walking the minefield like I won't get hurt by the mortars that we made but it's a little very cracking 287 00:27:35,740 --> 00:27:37,900 I'll guarantee your right a little bit 288 00:27:43,180 --> 00:27:45,180 Oh 289 00:28:00,380 --> 00:28:07,340 All right, okay, there's just a flesh one the minefield is scarily accurate and completely safe 290 00:28:13,500 --> 00:28:15,500 There goes the leg 291 00:28:17,420 --> 00:28:20,620 And when adam recovers from his gruesome fake death 292 00:28:23,580 --> 00:28:25,980 They can reset the field for vehicles 293 00:28:36,300 --> 00:28:42,540 Let me remind you we're testing the myth that a hovercraft can traverse a minefield without incident that it won't set off any of the mines 294 00:28:43,900 --> 00:28:45,180 Woo 295 00:28:45,180 --> 00:28:49,100 But this required us to answer the question of what in fact is a mine 296 00:28:49,420 --> 00:28:53,420 There are thousands of different kinds and they're set off by many different things 297 00:28:53,580 --> 00:28:56,460 Some are set off by electromagnetism some by vibration 298 00:28:56,540 --> 00:29:01,420 But the most common of all mines is set off by pressure. That's the kind we decided to go 299 00:29:02,140 --> 00:29:03,660 Oh 300 00:29:03,660 --> 00:29:06,860 It's effectively a scale with a bomb attached to it 301 00:29:08,620 --> 00:29:10,620 Oh 302 00:29:10,700 --> 00:29:12,300 Oh, you big baby 303 00:29:12,300 --> 00:29:18,380 So after their successful systems test the team recalibrates the mines to an anti vehicle setting 304 00:29:19,580 --> 00:29:26,780 And prepares for a control comparison. All right, david. So we set the mines to 300 pounds. All right 300 pounds excellent 305 00:29:27,820 --> 00:29:34,620 Before the hovercraft is sent into battle adam's jeep with fake plastic minigun will be used as a control 306 00:29:35,020 --> 00:29:40,060 This is where the rubber meets the road. It's time to do our vehicle versus mines test 307 00:29:41,420 --> 00:29:43,420 All right, jayme you ready 308 00:29:43,500 --> 00:29:45,020 Starting the engine 309 00:29:45,020 --> 00:29:50,540 And after we see what happens with that it'll be time to move on to sending our hovercraft across the same course 310 00:29:51,180 --> 00:29:56,700 Commence the vehicle mine setting test in three two one go 311 00:29:59,020 --> 00:30:02,060 The jeep weighs in at just over 3 000 pounds 312 00:30:06,860 --> 00:30:08,380 There goes one 313 00:30:08,380 --> 00:30:11,660 And one quarter of its weight 750 pounds 314 00:30:13,500 --> 00:30:19,100 Is focused through the relatively small contact area of each tire easily setting off 315 00:30:19,580 --> 00:30:22,620 Get my car dusty any of the mines they cross 316 00:30:23,980 --> 00:30:29,100 Now in the case of the hovercraft not all of its weight is concentrated into one small area 317 00:30:29,340 --> 00:30:32,940 Well, that worked quite well, didn't it? I guess now it's time for the hovercraft 318 00:30:33,580 --> 00:30:38,940 So the question here is is that weight or that down pressure that it's exerting on the ground 319 00:30:39,340 --> 00:30:41,340 Enough to set off one of these mines 320 00:30:43,340 --> 00:30:46,940 My prediction is that the hovercraft is going to make it just fine 321 00:30:47,180 --> 00:30:50,700 Even though it weighs fully loaded with the person over 600 pounds 322 00:30:51,020 --> 00:30:56,940 I don't see it exerting 300 pounds down on its underskirt. It's just I don't it's not going to happen 323 00:30:57,900 --> 00:31:05,100 We're about to find out with janey in the hot seat and a high tech minefield rigged and ready to blow 324 00:31:05,740 --> 00:31:12,060 Can a hovercraft really float through an anti vehicle minefield? Oh, yeah, here it goes 325 00:31:14,300 --> 00:31:16,300 Oh, yeah 326 00:31:17,740 --> 00:31:19,500 Yeah 327 00:31:19,500 --> 00:31:22,460 It didn't set up a thing that was awesome. Yeah 328 00:31:23,420 --> 00:31:26,620 That was smooth explosion-free sailing 329 00:31:27,180 --> 00:31:28,940 Oh, yeah 330 00:31:28,940 --> 00:31:32,940 The s-curve layout ensured janey crossed a majority of the mines 331 00:31:33,660 --> 00:31:41,500 But not a single one went boom. Yeah, you want to come back around for a second run on my way? Maybe a little slower this time 332 00:31:46,380 --> 00:31:48,380 Yeah 333 00:31:48,940 --> 00:31:56,300 Despite reducing speed giving the mines more time to register the passing hovercraft the hinderman gets away unharmed 334 00:31:57,580 --> 00:31:59,820 Not a thing that was beautiful 335 00:32:01,180 --> 00:32:03,180 Yeah 336 00:32:04,300 --> 00:32:09,820 Well, there you have it we drove across the minefield with the vehicle and we're setting off the mines 337 00:32:12,380 --> 00:32:14,380 The hovercraft not so much 338 00:32:18,060 --> 00:32:21,660 I was right. I like being right every now and then 339 00:32:21,660 --> 00:32:29,900 Well, it may seem counterintuitive to you that a 600 pound hovercraft can't set off a mine engineered to go off at 300 pounds 340 00:32:29,900 --> 00:32:33,900 But this myth is all about the exact kind of pressure a human foot 341 00:32:34,540 --> 00:32:35,980 A car tire 342 00:32:35,980 --> 00:32:37,980 Those are point sources of pressure 343 00:32:38,140 --> 00:32:45,660 But the hovercraft is distributing its weight across its entire footprint across the entire cushion of air that it's riding on 344 00:32:45,980 --> 00:32:48,300 That's why it can't set off our minds 345 00:32:49,180 --> 00:32:53,500 That's why it is the perfect craft for making its way across a minefield 346 00:32:54,380 --> 00:32:56,620 But it still weighs 600 pounds 347 00:32:58,380 --> 00:33:04,460 How well does it spread that load and can a hovercraft cross any minefield at any pressure setting 348 00:33:04,860 --> 00:33:09,260 Now it's the moment of truth our minefield is set to an anti-personnel pressure 349 00:33:09,340 --> 00:33:15,900 That is 35 pounds to trigger our minds. I've already walked it and shown that i'm plenty to trigger it 350 00:33:16,700 --> 00:33:19,580 Okay, adam you're good to go 351 00:33:20,380 --> 00:33:24,460 All right, here we go traversing a minefield in a hovercraft 352 00:33:25,500 --> 00:33:30,140 Set the anti-personnel setting in three two here we go 353 00:33:45,980 --> 00:33:50,300 Same thing no mine action. Yeah, that is awesome 354 00:33:51,900 --> 00:33:56,700 The lines set to go off at the lightest footstep are once again unmoved 355 00:33:57,900 --> 00:34:04,540 Adam then does his best to linger with several 360s. Yeah, can you hold it in one spot? 356 00:34:09,900 --> 00:34:14,060 But the hovercraft at its cushion of air defies death from below 357 00:34:16,620 --> 00:34:18,620 Ha ha ha ha 358 00:34:21,500 --> 00:34:24,940 At this point it's looking mighty good for this myth, but are we done? 359 00:34:25,740 --> 00:34:27,740 Come on, you know us 360 00:34:28,060 --> 00:34:32,700 You know, we're gonna take it to the most extreme place we can that's what we're about to do 361 00:34:33,100 --> 00:34:35,660 So we've set this to go off at five pounds 362 00:34:36,380 --> 00:34:38,380 The easter bunny could set this off 363 00:34:39,100 --> 00:34:41,100 Ha ha 364 00:34:44,060 --> 00:34:47,900 Okay, here we go, it's the ultimate test for this myth 365 00:34:48,700 --> 00:34:54,460 The Heinemann and hovercraft are 120 times heavier than each mine's threshold 366 00:34:58,940 --> 00:35:02,640 But once again they float serenely across unharmed 367 00:35:09,020 --> 00:35:14,060 Didn't set off a single mine that is beautiful. I love it. So how does this work? 368 00:35:14,700 --> 00:35:16,700 Well, the answer is in the numbers 369 00:35:16,860 --> 00:35:24,060 If you divide the weight of the hovercraft by the contact area you get about 0.06 pounds per square inch of downward pressure 370 00:35:24,460 --> 00:35:27,020 So there's not nearly enough pressure per square inch 371 00:35:31,420 --> 00:35:37,020 Well, I gotta say I think this is about as easy a myth to call as we've ever encountered. Yeah, it's confirmed 372 00:35:37,180 --> 00:35:45,820 Totally confirmed the hovercraft is the absolute vehicle of choice for traversing a minefield sure is I gotta figure out how to get myself one of these 373 00:35:53,740 --> 00:35:56,220 How am I supposed to get out of this minefield? 374 00:36:03,100 --> 00:36:06,380 Coming up on this explosive final season farewell 375 00:36:06,780 --> 00:36:09,500 84 pounds of dynamite 185 pounds of pure man 376 00:36:10,540 --> 00:36:13,660 Jamie brings the big boom one go 377 00:36:15,180 --> 00:36:17,180 Yep 378 00:36:21,100 --> 00:36:25,980 To celebrate the final season, this is the myth busters number crunching countdown 379 00:36:28,540 --> 00:36:30,540 Synonymous with the show 380 00:36:30,540 --> 00:36:33,500 The teams racked up an impressive number of countdowns 381 00:36:34,460 --> 00:36:36,460 920 of them 382 00:36:38,460 --> 00:36:46,300 They've used 18 tons and more than eight types of explosive the most famous was 850 pounds of anphal 383 00:36:48,060 --> 00:36:50,060 And the biggest 384 00:36:51,740 --> 00:36:59,660 5 000 pounds, Jamie wants big bones, but mostly it's been an epic orgy of operatic carnage 385 00:37:03,500 --> 00:37:05,500 So 386 00:37:27,020 --> 00:37:29,020 Looks good. All right 387 00:37:29,340 --> 00:37:35,260 It's the last thing that truck will ever do if you're just tuning in we've been messing stuff up all over the place 388 00:37:37,100 --> 00:37:42,540 Unexploded tnt there and in the process have had a few of our own MacGyver moments 389 00:37:43,740 --> 00:37:48,620 Yes, that's a male truck inside of it 84 pounds of dynamite any minute now 390 00:37:49,820 --> 00:37:51,820 We're gonna find out just how MacGyver we are 391 00:37:52,460 --> 00:37:56,620 But first this time they got to ensure everything goes boom 392 00:37:56,940 --> 00:38:02,780 The last time we had some bundles of dynamite that were sitting underneath a table. Well, it didn't work so well 393 00:38:03,740 --> 00:38:07,500 Our best guess is that we detonated two sticks of dynamite 394 00:38:08,380 --> 00:38:12,460 This time around i'm going to be putting our dynamite inside a box 395 00:38:12,540 --> 00:38:16,940 It's made out of one inch plywood and it's going to be completely sealed and anchored 396 00:38:17,660 --> 00:38:19,660 It's going to work this time 397 00:38:20,060 --> 00:38:23,260 It will explode, but will the cement smother the blast? 398 00:38:23,980 --> 00:38:25,980 Oh 399 00:38:26,300 --> 00:38:28,300 That's our package 400 00:38:28,940 --> 00:38:33,500 And the first is that that concrete is heavy and it's gonna absorb a lot of the explosion 401 00:38:33,820 --> 00:38:39,500 84 pounds of dynamite 185 pounds of pure man on the other hand. There's something known as water hammer 402 00:38:39,740 --> 00:38:44,220 Push good and that's what happens if you close a tap really quickly and it can deliver a 403 00:38:44,780 --> 00:38:48,620 Hydraulic shock to the plumbing which can actually rupture it. Ha ha ha ha 404 00:38:49,340 --> 00:38:50,940 That is beautiful 405 00:38:50,940 --> 00:38:57,980 Now this concrete could deliver something like a water hammer to the exterior of the truck and busted up really efficiently 406 00:38:58,300 --> 00:38:59,980 There we go 407 00:38:59,980 --> 00:39:06,780 Now whether that does it more efficiently than it did without any concrete in the mail truck. That's what we're about to test 408 00:39:07,660 --> 00:39:08,860 That's it 409 00:39:08,860 --> 00:39:10,860 Let's cap in get out of here. Okay 410 00:39:11,820 --> 00:39:15,820 It's been one of the most testing test setups in myth busters history 411 00:39:17,260 --> 00:39:19,740 All right, sorry you ready i'm ready. I'll go ahead and arm it 412 00:39:20,940 --> 00:39:25,180 But they're primed to finally find out if magaibur's quick thinking cement solution 413 00:39:26,780 --> 00:39:28,780 Would have saved the situation 414 00:39:29,020 --> 00:39:33,740 This is magaibur mail truck filled with cement and 84 pounds of dynamite 415 00:39:35,340 --> 00:39:37,340 And three 416 00:39:37,740 --> 00:39:39,740 two 417 00:39:39,980 --> 00:39:41,980 One go 418 00:39:46,140 --> 00:39:48,140 It made a jet straight up 419 00:39:51,180 --> 00:39:53,180 That was a thud 420 00:40:06,540 --> 00:40:08,540 Truck's all gone 421 00:40:11,900 --> 00:40:14,380 The truck was completely destroyed 422 00:40:15,020 --> 00:40:17,020 Well, there's your problem 423 00:40:17,020 --> 00:40:22,860 But there is evidence that the concrete altered the characteristics and intensity of the explosion 424 00:40:23,980 --> 00:40:28,380 This is really interesting. Jamie and that first blast there was a shock wave 425 00:40:32,140 --> 00:40:35,180 And it knocked all the legs of our shrapnel catchers off 426 00:40:36,060 --> 00:40:38,620 But i'm looking at the shrapnel catchers that are nearby 427 00:40:39,180 --> 00:40:45,180 They're mostly intact. So i'm going to go out on a limb and say there was not a significant shock wave emanating out 428 00:40:45,180 --> 00:40:49,420 It looks like probably most of that force went up and what was coming out was all shrapnel 429 00:40:51,740 --> 00:40:53,740 This is interesting 430 00:40:55,100 --> 00:40:59,180 Unlike the control this time there's a hole in the ground where the truck used to be wow 431 00:40:59,580 --> 00:41:05,660 We made a crater and the debris field had 250 feet. It's not nearly as widespread 432 00:41:05,820 --> 00:41:07,820 It's less than half the size of the control 433 00:41:09,820 --> 00:41:11,820 And it makes sense if you think about it 434 00:41:11,820 --> 00:41:18,780 Most of the concrete surrounded the explosive meaning that the energy was directed up and down instead of outward towards the shrapnel catchers 435 00:41:19,820 --> 00:41:23,420 Yep, but although the plywood passers-by weren't ripped apart 436 00:41:25,260 --> 00:41:27,260 They were peppered 437 00:41:28,860 --> 00:41:32,380 Let's face it the concrete may have altered the direction of the pressure wave 438 00:41:34,140 --> 00:41:40,460 But it didn't save the day the shrapnel catchers are riddled with holes the aggregate in the concrete the loose rocks 439 00:41:40,540 --> 00:41:47,180 It all became a lethal shower of death and the truck did not survive in any way like it did in the clip 440 00:41:47,820 --> 00:41:49,820 found the back door 441 00:41:50,220 --> 00:41:52,220 This one's pretty easy to call 442 00:41:56,540 --> 00:42:03,420 All right, mr. Heidemann time to call this did macgyver's concrete technique alter the blast it did indeed 443 00:42:03,900 --> 00:42:06,620 Did it protect people in the vicinity? 444 00:42:07,180 --> 00:42:08,060 Not at all 445 00:42:08,060 --> 00:42:11,340 No, does it match the clip that we saw on the tv show? 446 00:42:12,140 --> 00:42:16,460 No, no, I think the call on this one is pretty clear. It's busted. It's totally busted 447 00:42:21,660 --> 00:42:26,060 You know at this point we've probably blown up more weird crap than anybody alive