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