WEBVTT 1 00:00:00.080 --> 00:00:03.319 I want you to just close your eyes per second 2 00:00:03.319 --> 00:00:07.200 and put yourself in a very specific, like incredibly terrifying scenario. 3 00:00:07.280 --> 00:00:08.000 Okay, I'm ready. 4 00:00:08.279 --> 00:00:12.000 So you are sitting in the cabin of a Boeing 5 00:00:12.160 --> 00:00:15.880 seven forty seven. You are thirty seven thousand feet up, 6 00:00:16.079 --> 00:00:19.559 flying through the pitch black night over the vast, totally 7 00:00:19.640 --> 00:00:21.480 empty expanse of the Indian. 8 00:00:21.160 --> 00:00:23.399 Ocean, just miles of dark water below. 9 00:00:23.359 --> 00:00:25.600 Right exactly, And you look at your window and instead 10 00:00:25.600 --> 00:00:28.879 of just darkness, you see this shimmering, ghostly white light 11 00:00:29.000 --> 00:00:31.079 just kind of clinging to the wings of the airplane. 12 00:00:31.239 --> 00:00:34.600 Oh wow, But it actually gets worse because a few 13 00:00:34.600 --> 00:00:38.719 seconds later you see forty foot jets of solid flame 14 00:00:38.840 --> 00:00:40.719 shooting straight out of the back of the engines. 15 00:00:40.920 --> 00:00:43.880 I mean, the visual alone is horrifying. Yeah, and the 16 00:00:43.920 --> 00:00:47.640 physical sensation inside that cabin would have been just as alarming, 17 00:00:47.880 --> 00:00:48.039 you know. 18 00:00:48.240 --> 00:00:49.439 Yeah, I can't even imagine. 19 00:00:49.479 --> 00:00:53.520 Because the deafening, steady roar of those massive jet engines, 20 00:00:53.759 --> 00:00:57.439 it starts to grind and choke. Survivors actually later describe 21 00:00:57.479 --> 00:01:00.719 it sounding like a concrete mixer just grinding up, and. 22 00:01:00.679 --> 00:01:03.359 Then absolute dead silence. All four engines are gone. You 23 00:01:03.399 --> 00:01:04.840 are literally falling out of the sky. 24 00:01:05.000 --> 00:01:08.879 It's the ultimate nightmare scenario, it really is. And well, 25 00:01:09.239 --> 00:01:12.879 welcome to this deep dive today. We are stepping into 26 00:01:12.879 --> 00:01:16.760 the rolls of aviation experts and accident investigators and we 27 00:01:16.840 --> 00:01:18.719 have a very specific mission. 28 00:01:18.640 --> 00:01:23.159 Right We're going to forensically examine three harrowing true stories 29 00:01:23.159 --> 00:01:25.480 of mid air emergencies from the nineteen seventies and eighties. 30 00:01:25.560 --> 00:01:28.680 Yeah, and we're doing this because, frankly, every single time 31 00:01:28.719 --> 00:01:31.599 you board a commercial flight today, the safety features you 32 00:01:31.680 --> 00:01:35.079 take conpolitely for granted, from the tiny lights on the 33 00:01:35.120 --> 00:01:37.760 floor aisle to the hidden mechanics of the cargo doors 34 00:01:37.840 --> 00:01:40.439 right below your feet, they were all paid for by 35 00:01:40.480 --> 00:01:43.120 the terrifying ordeals of the passengers and crews in the 36 00:01:43.159 --> 00:01:44.480 stories we're unpacking today. 37 00:01:44.599 --> 00:01:47.920 Exactly, the safety of modern air travel is quite literally 38 00:01:47.920 --> 00:01:49.599 written in blood and near misses. 39 00:01:49.719 --> 00:01:50.239 Yeah. 40 00:01:50.280 --> 00:01:53.519 It is an incredibly robust system today precisely because it 41 00:01:53.560 --> 00:01:58.040 was built on learning from these catastrophic, just unthinkable failures 42 00:01:58.079 --> 00:01:58.640 of the past. 43 00:01:58.799 --> 00:02:00.760 So let's start with that silence seven four to seven 44 00:02:00.799 --> 00:02:03.920 falling over the ocean. This is British Airways flight nine 45 00:02:04.120 --> 00:02:05.359 June nineteen eighty two. 46 00:02:05.560 --> 00:02:09.479 It's a routine flight cruising over Indonesia heading to Australia, 47 00:02:09.759 --> 00:02:13.680 the crew is fresh, everything seems completely fine. Radar actually 48 00:02:13.680 --> 00:02:16.879 shows smooth sailing for hundreds of miles. 49 00:02:16.560 --> 00:02:18.120 Ahead, nothing on the screens at all. 50 00:02:18.439 --> 00:02:23.039 Nothing. But then the passengers start noticing this ominous creeping 51 00:02:23.159 --> 00:02:25.400 haze just kind of filling the cabin. 52 00:02:25.719 --> 00:02:28.439 And you know, in nineteen eighty two, smoking was actually 53 00:02:28.520 --> 00:02:29.719 still allowed on airplanes. 54 00:02:29.879 --> 00:02:31.439 Oh right, I always forget that. 55 00:02:31.759 --> 00:02:35.080 Yeah, so a little haze wasn't immediately alarming to people, 56 00:02:35.280 --> 00:02:39.719 but the cabin crew quickly realized this smoke was entirely different. 57 00:02:39.800 --> 00:02:42.680 Oh so, well, it was thick, and it smelt heavily 58 00:02:42.719 --> 00:02:46.319 of sulfur, almost like a really strong electrical fire mixed 59 00:02:46.319 --> 00:02:47.280 with struck matches. 60 00:02:47.520 --> 00:02:49.240 That is not what you want to smell at thirty 61 00:02:49.280 --> 00:02:50.400 seven thousand feet. 62 00:02:50.240 --> 00:02:54.039 Definitely not. So they initiated this quiet, intense search for 63 00:02:54.080 --> 00:02:58.199 a fire inside the cabin, pulling up carpets and checking laboratories, 64 00:02:58.560 --> 00:03:01.599 but they couldn't find a single lane anywhere. 65 00:03:01.159 --> 00:03:04.199 Because the problem wasn't actually inside the plane. Right up 66 00:03:04.199 --> 00:03:07.439 in the cockpit, the flight crew start seeing these intense, 67 00:03:07.560 --> 00:03:11.439 blinding pricks of light completely covering the windshield, which is terrifying. 68 00:03:11.680 --> 00:03:14.000 It looks exactly like Sane Almo's fire, which is a 69 00:03:14.039 --> 00:03:18.039 phenomenon you usually only see when flying through highly charged thunderclouds. 70 00:03:18.080 --> 00:03:19.520 Yeah, it's electrical discharge. 71 00:03:19.560 --> 00:03:21.840 But they are looking at their weather radar and the 72 00:03:21.919 --> 00:03:24.919 screen is completely clear, like there is not a single 73 00:03:25.000 --> 00:03:26.120 rain cloud in the sky. 74 00:03:26.439 --> 00:03:29.439 The psychological toll of that confusion is just it's hard 75 00:03:29.479 --> 00:03:34.479 to overstate. You have a brilliant white, shimmering light essentially 76 00:03:34.520 --> 00:03:38.400 blinding the pilots, right yeah, and passengers are watching massive 77 00:03:38.439 --> 00:03:41.000 flames shoot out of the engines, but the instruments are 78 00:03:41.039 --> 00:03:43.599 telling the crew that the sky is perfectly clear. It 79 00:03:43.639 --> 00:03:46.560 makes no sense none, And then one by one the 80 00:03:46.560 --> 00:03:50.840 engine surge make that horrible concrete mixer grading sound, and 81 00:03:50.879 --> 00:03:54.000 they simply die, all four of them, all four within 82 00:03:54.039 --> 00:03:55.719 a minute and a half. They go from a healthy 83 00:03:55.800 --> 00:03:59.680 four engine jumbo jet to a three hundred ton metal. 84 00:03:59.360 --> 00:04:03.439 Glider plunging from thirty seven thousand feet and you know, 85 00:04:03.520 --> 00:04:06.080 the autopilot doesn't even disengage the way it's supposed to 86 00:04:06.120 --> 00:04:08.439 do in the training simulators. Oh really, Yeah, So the 87 00:04:08.479 --> 00:04:11.039 crew has to start a manual engine restart drill, which 88 00:04:11.080 --> 00:04:15.439 is this incredibly complex checklist that normally takes three full 89 00:04:15.479 --> 00:04:16.839 minutes to execute. 90 00:04:16.759 --> 00:04:19.279 And time is the one thing they don't have exactly. 91 00:04:19.560 --> 00:04:22.399 They calculate their descent rate and figure they only have 92 00:04:22.439 --> 00:04:26.560 about ten chances to get an engine going before they 93 00:04:26.680 --> 00:04:28.600 hit the freezing waters of the Indian Ocean. 94 00:04:28.800 --> 00:04:32.480 And compounding all of this is the immediate loss of cabin. 95 00:04:32.120 --> 00:04:35.199 Pressure, right because the engines control that exactly. 96 00:04:35.720 --> 00:04:38.800 The jet engines are what actually pump pressurized air into 97 00:04:38.839 --> 00:04:42.360 the cabin to keep everyone breathing at high altitudes. So 98 00:04:42.519 --> 00:04:46.439 without the engines, the cabin pressure drops rapidly to match 99 00:04:46.519 --> 00:04:48.000 the deadly thin air outside. 100 00:04:48.120 --> 00:04:52.480 So absolute panic sets in the yellow oxygen masks drop 101 00:04:52.519 --> 00:04:55.639 from the ceiling. But and this is just the worst timing, 102 00:04:56.120 --> 00:04:59.199 the first officer's mask is broken. Oh no, yeah, the 103 00:04:59.240 --> 00:05:02.160 tube literally separates from the mask right in his hands. 104 00:05:02.360 --> 00:05:05.079 So the captain is forced to make a terrifying maneuver. 105 00:05:04.720 --> 00:05:06.000 To get to lower altitude right. 106 00:05:06.040 --> 00:05:08.560 Yeah, to save his co pilot from passing out. He 107 00:05:08.560 --> 00:05:11.800 has to put this massive engineless plane into a steep 108 00:05:12.000 --> 00:05:15.680 roller coaster dive, dropping six thousand feet in a single. 109 00:05:15.439 --> 00:05:17.439 Minute, just to reach an altitude where the air is 110 00:05:17.480 --> 00:05:20.000 thick enough for his crew to actually breathe exactly. I mean, 111 00:05:20.000 --> 00:05:23.959 that is an incredible display of airmanship, just acting entirely 112 00:05:24.000 --> 00:05:29.839 on instinct. But dropping altitude forces another terrifying geographic reality 113 00:05:29.839 --> 00:05:30.160 on them. 114 00:05:30.399 --> 00:05:31.120 The mountains. 115 00:05:31.519 --> 00:05:37.279 Yes, yeah, there is a massive jagged mountain range stretching 116 00:05:37.279 --> 00:05:40.519 across the island of Java, directly in their flight path. 117 00:05:40.600 --> 00:05:40.720 Right. 118 00:05:41.120 --> 00:05:43.480 They need to be at least eleven five hundred feet 119 00:05:43.560 --> 00:05:46.360 high just to clear those peaks. But they are bleeding 120 00:05:46.399 --> 00:05:47.800 altitude so fast. 121 00:05:48.079 --> 00:05:50.360 So Captain has to make an impossible choice. Does he 122 00:05:50.519 --> 00:05:53.079 ditch the plane and the pitch black ocean, which is 123 00:05:53.079 --> 00:05:56.160 a maneuver he has literally never practiced outside of a simulator, 124 00:05:56.800 --> 00:06:01.160 or does he risk crashing blindly into the mountains. He decides, 125 00:06:01.199 --> 00:06:02.800 if they don't get an engine started in the next 126 00:06:02.839 --> 00:06:04.920 few minutes, he will turn the plane around and take 127 00:06:04.920 --> 00:06:06.079 his chances with the ocean. 128 00:06:06.160 --> 00:06:06.639 Wow. 129 00:06:06.759 --> 00:06:09.120 So they are running the restart drill over and over 130 00:06:09.439 --> 00:06:13.000 fifty times, maybe more, and then a miracle happens. 131 00:06:13.040 --> 00:06:13.680 They get one going. 132 00:06:13.920 --> 00:06:16.920 Yes, just as they're running out of altitude, engine number 133 00:06:16.920 --> 00:06:19.399 four suddenly roars back to life, and then a few 134 00:06:19.399 --> 00:06:22.560 moments later engine through kitches. Then the final two. 135 00:06:22.639 --> 00:06:23.839 That is unbelievable. 136 00:06:23.920 --> 00:06:26.680 Yeah, they are back in business. They divert to Jakarta, 137 00:06:27.040 --> 00:06:31.399 and somehow, despite their windshield being completely sand blasted opaque, 138 00:06:31.399 --> 00:06:34.720 and their ground guidance equipment failing at the airport, they 139 00:06:34.759 --> 00:06:36.759 manually land the plane safely. 140 00:06:37.000 --> 00:06:42.079 So everyone survives. But the mystery for the accident investigators 141 00:06:42.120 --> 00:06:43.680 was really just beginning. 142 00:06:43.759 --> 00:06:45.480 Yeah, because they had no idea what happened. 143 00:06:45.560 --> 00:06:47.360 Right when they looked at the plane the next morning 144 00:06:47.360 --> 00:06:50.279 on the tarmac, the paint was completely stripped off the 145 00:06:50.360 --> 00:06:53.639 leading edges. The windshield was deeply scarred and frosted over. 146 00:06:53.759 --> 00:06:56.199 So I'm putting myself in the shoes of investigator Malcolm 147 00:06:56.240 --> 00:06:59.959 Greyburn here. He strips down these massive engines and finds 148 00:07:00.079 --> 00:07:04.120 the internal components completely choked with fine dust, ground up 149 00:07:04.240 --> 00:07:05.639 rock and sand. 150 00:07:05.519 --> 00:07:08.879 Which points to one very specific geological event. 151 00:07:09.160 --> 00:07:12.399 Yeah. It turns out that exact night, Mount glongung, a 152 00:07:12.480 --> 00:07:16.560 volcano like one hundred and sixty kilometers away, had erupted violently. 153 00:07:17.000 --> 00:07:20.160 Flight nine had flown blindly into a massive ash. 154 00:07:19.839 --> 00:07:21.759 Cloud, completely invisible to them. 155 00:07:21.879 --> 00:07:23.480 Right, but wait, I have to stop you here. I've 156 00:07:23.480 --> 00:07:26.199 always wondered about this volcanic ash is just rock dust. 157 00:07:26.120 --> 00:07:28.839 Right, Basically, yes, shouldn't. 158 00:07:28.399 --> 00:07:31.720 A massive jet turbine spinning at thousands of RPMs just 159 00:07:31.759 --> 00:07:34.399 blow that dust straight out the exhaust? Like? Why would 160 00:07:34.399 --> 00:07:35.240 it kill the engine? 161 00:07:35.279 --> 00:07:37.600 Well, that is the logical assumption. But let's look at 162 00:07:37.600 --> 00:07:40.639 the temperatures inside a jet engine. An engine is essentially 163 00:07:40.639 --> 00:07:44.199 a continuous explosion. Okay, It sucks in air, compresses it, 164 00:07:44.480 --> 00:07:47.319 and ignites it with jet fuel at around two thousand 165 00:07:47.319 --> 00:07:51.680 degrees celsius. Now, volcanic ash is composed of pulverized rock 166 00:07:52.040 --> 00:07:52.680 and glass. 167 00:07:52.879 --> 00:07:54.079 Oh I see where this is going. 168 00:07:54.279 --> 00:07:56.680 Yeah, the melting point of that specific ash is around 169 00:07:56.720 --> 00:07:58.199 thirteen hundred degrees celsius. 170 00:07:58.319 --> 00:08:01.240 Oh wow, So the engine is actual burning hotter than 171 00:08:01.240 --> 00:08:03.600 the melting point of the rock. It's like a giant 172 00:08:03.639 --> 00:08:06.000 blast furnace inhaling pulverized glass. 173 00:08:06.120 --> 00:08:09.199 Precisely, the ash ended the engine as a dry dust 174 00:08:09.560 --> 00:08:12.959 hit the combustion chamber and instantly melted into a sticky 175 00:08:13.120 --> 00:08:14.240 molten glass goo. 176 00:08:14.879 --> 00:08:16.199 That sounds disastrous. 177 00:08:16.360 --> 00:08:19.720 It was this molten rock completely coated the turbine blades, 178 00:08:20.000 --> 00:08:23.000 disrupting the precise aerodynamics needed to keep the engine running 179 00:08:23.279 --> 00:08:26.839 and ultimately suffocated the combustion process. That's what caused the 180 00:08:26.839 --> 00:08:27.879 engines to flame out. 181 00:08:28.040 --> 00:08:30.879 Okay, but that brings up an even bigger question. If 182 00:08:30.879 --> 00:08:34.519 the engines were choked with melted rock, how on earth 183 00:08:34.600 --> 00:08:37.480 did they magically restart before the plane hit the ocean. 184 00:08:37.759 --> 00:08:41.000 That is the ultimate aha moment of this investigation, and 185 00:08:41.039 --> 00:08:42.799 it all comes down to the physics of cooling. 186 00:08:43.000 --> 00:08:44.159 Okay, explain that. 187 00:08:44.200 --> 00:08:47.320 When the engines flamed out, they obviously stopped burning fuel 188 00:08:47.600 --> 00:08:50.600 right because they were no longer generating that two thousand 189 00:08:50.679 --> 00:08:54.440 degree heat. The internal metal rapidly cooled as the plane 190 00:08:54.440 --> 00:08:56.279 fell through the freezing high altitude air. 191 00:08:56.519 --> 00:09:00.000 Let me guess the molten glass goo cooled down right 192 00:09:00.080 --> 00:09:00.879 along with it. 193 00:09:00.879 --> 00:09:04.519 It did. The sticky ash solidified back into solid rock. 194 00:09:05.000 --> 00:09:07.519 But here's the trick. Because the metal engine blades and 195 00:09:07.559 --> 00:09:10.639 the glass ash contract at totally different rates. As they 196 00:09:10.679 --> 00:09:13.919 cool down, the ash became incredibly. 197 00:09:13.320 --> 00:09:16.039 Brittle, like hard candy exactly. 198 00:09:15.960 --> 00:09:18.080 So the sheer force of the air rushing through the 199 00:09:18.120 --> 00:09:21.639 dead wind milling engines simply shattered the brittle glass off 200 00:09:21.679 --> 00:09:22.200 the blades. 201 00:09:22.360 --> 00:09:22.840 Oh wow. 202 00:09:22.960 --> 00:09:25.919 Yeah, the cooling down process actually cleared the airflow just 203 00:09:25.960 --> 00:09:28.440 in time for the crew to successfully re ignite the fuel. 204 00:09:28.759 --> 00:09:32.679 That is an unbelievable piece of luck driven by pure physics. 205 00:09:33.000 --> 00:09:37.600 It makes total sense why this altered global aviation volcanic 206 00:09:37.679 --> 00:09:41.159 ash is dry rock, It doesn't contain water, and standard 207 00:09:41.200 --> 00:09:44.159 weather radar on airplanes bounce as signals off moisture like 208 00:09:44.320 --> 00:09:48.759 rain or hail. So this massive, deadly cloud was totally 209 00:09:48.799 --> 00:09:50.679 invisible to their instruments, which. 210 00:09:50.519 --> 00:09:53.840 Is why today we have the volcanic ash Advisory Centers. 211 00:09:53.919 --> 00:09:54.720 Well that makes sense. 212 00:09:54.840 --> 00:09:57.679 Yeah, this single incident forced a brand new line of 213 00:09:57.720 --> 00:10:02.720 communication between geologists whom want seismic activity and the international 214 00:10:02.720 --> 00:10:05.720 airlines that actually fly over those regions. 215 00:10:05.759 --> 00:10:08.879 So BA Flight nine is a story about trusting instruments 216 00:10:08.919 --> 00:10:12.639 that simply cannot see the invisible forces of nature. But 217 00:10:12.720 --> 00:10:15.480 our next case transitions us into something much. 218 00:10:15.360 --> 00:10:16.559 Darker, definitely darker. 219 00:10:16.840 --> 00:10:19.759 What happens when the hazard isn't an unpredictable act of nature, 220 00:10:19.840 --> 00:10:23.120 but a deliberate human choice. What happens when the instruments 221 00:10:23.120 --> 00:10:25.840 are literally lying to the pilots because of a fatal 222 00:10:25.879 --> 00:10:26.480 design flaw. 223 00:10:26.600 --> 00:10:29.000 Right, we're talking about the McDonald Douglas DC ten and 224 00:10:29.080 --> 00:10:31.720 a disaster driven entirely by corporate bureaucracy. 225 00:10:32.039 --> 00:10:34.799 So to understand this, we go back to June nineteen 226 00:10:34.799 --> 00:10:39.200 seventy two, American Airlines Flight ninety six, a brand new 227 00:10:39.440 --> 00:10:43.039 DC ten literally just the fifth one ever built, takes 228 00:10:43.080 --> 00:10:43.600 off from. 229 00:10:43.399 --> 00:10:45.000 Detroit, just a normal flight. 230 00:10:45.200 --> 00:10:48.360 Yeah, it's climbing through eleven five hundred feet when suddenly 231 00:10:48.600 --> 00:10:52.759 the pilots here a massive bang followed by an explosive decompression. 232 00:10:53.000 --> 00:10:56.120 It's pure chaos in the cabin. The floor in the 233 00:10:56.120 --> 00:11:00.200 rear passenger section literally collapses downward into the cargo hold. 234 00:11:00.240 --> 00:11:01.240 I can't even picture that. 235 00:11:01.440 --> 00:11:04.360 It gets worse a coffin being transported down There is 236 00:11:04.399 --> 00:11:06.879 suck completely out of the airplane and falls to the earth. 237 00:11:06.919 --> 00:11:08.080 That is insane. 238 00:11:08.159 --> 00:11:10.559 But the most terrifying part isn't the hole in the plane. 239 00:11:11.080 --> 00:11:13.720 The severed floor takes out the vital control cables running 240 00:11:13.759 --> 00:11:14.279 underneath it. 241 00:11:14.399 --> 00:11:16.759 Oh no, so they can't steer right. 242 00:11:16.840 --> 00:11:19.559 The crew loses control of the tail engine, the elevators, 243 00:11:19.759 --> 00:11:22.399 and the rudder, which is jammed hard to the right. 244 00:11:22.600 --> 00:11:25.679 Under normal circumstances, an aircraft with a jammed rudder and 245 00:11:25.759 --> 00:11:29.879 severed elevator cables is a boomed aircraft absolutely. But Captain 246 00:11:29.919 --> 00:11:33.799 Bryce McCormick performed an absolute masterclass and emergency flying with 247 00:11:33.879 --> 00:11:37.200 his primary control severed. He used differential engine thrust to 248 00:11:37.240 --> 00:11:38.480 steer the crippled plane. 249 00:11:38.799 --> 00:11:42.440 Explain how that works, because visualizing that is just wild. 250 00:11:42.600 --> 00:11:44.679 Okay, So think of it like being in a rowboat. 251 00:11:45.279 --> 00:11:48.639 If you pull both oars equally, you go straight right. 252 00:11:48.679 --> 00:11:51.200 If you only pull the left or the boat turns 253 00:11:51.240 --> 00:11:54.639 to the right. McCormick did the exact same thing with 254 00:11:54.720 --> 00:11:55.399 his wing. 255 00:11:55.200 --> 00:11:56.720 Engine, using the engines to steer. 256 00:11:56.879 --> 00:12:00.519 Yeah, by throttling up the left engine and throttle down 257 00:12:00.559 --> 00:12:04.159 the right engine, the asymmetric thrust pushed the nose of 258 00:12:04.200 --> 00:12:06.399 the plane around, fighting the jammed rudder. 259 00:12:06.519 --> 00:12:07.360 That is brilliant. 260 00:12:07.559 --> 00:12:10.240 Using only engine power, he actually managed to muscle that 261 00:12:10.279 --> 00:12:12.480 plane back to Detroit for a safe landing. 262 00:12:12.639 --> 00:12:17.320 Absolute hero, So naturally the NTSB, the National Transportation Safety Board, 263 00:12:17.320 --> 00:12:20.720 gets involved. Investigator Chuck Miller looks at the plane and 264 00:12:20.799 --> 00:12:25.720 realizes the rear cargo door just blew completely off the hinges. 265 00:12:25.320 --> 00:12:26.240 And why did that happen? 266 00:12:26.679 --> 00:12:29.559 The reason comes down to a structural design choice. To 267 00:12:29.639 --> 00:12:33.240 maximize cargo space inside the belly of the plane, McDonald 268 00:12:33.240 --> 00:12:36.200 Douglas designed the cargo door to open outward like a 269 00:12:36.200 --> 00:12:37.000 normal house. 270 00:12:36.799 --> 00:12:39.480 Door, which is a highly dangerous design choice. For a 271 00:12:39.519 --> 00:12:41.799 pressurized toobe right, very dangerous. 272 00:12:42.559 --> 00:12:45.799 Most aircraft doors are what we call plug doors. To 273 00:12:45.879 --> 00:12:49.159 visualize a plug door, think of a bathtub stopper. Okay, 274 00:12:49.240 --> 00:12:51.600 you put it in from the inside. The more water 275 00:12:51.600 --> 00:12:54.399 pressure pushes down on it, the tighter it actually seals 276 00:12:54.440 --> 00:12:55.000 into the drain. 277 00:12:55.200 --> 00:12:57.200 Oh, like it seals itself exactly. 278 00:12:57.600 --> 00:13:00.360 A plug door on an airplane works the exact same way. 279 00:13:00.799 --> 00:13:04.120 The massive air pressure inside the cabin pushes the door 280 00:13:04.159 --> 00:13:07.679 tighter into the frame. It's physically impossible for it to. 281 00:13:07.600 --> 00:13:09.360 Blow out, right, That makes total sense. 282 00:13:09.600 --> 00:13:12.519 But an outward opening door is like trying to hold 283 00:13:12.559 --> 00:13:15.519 that baptub stopper from underneath the drain while the tub 284 00:13:15.600 --> 00:13:19.000 is full of water. It relies entirely on its mechanical 285 00:13:19.080 --> 00:13:22.679 locking latches to hold back thousands of pounds of outward. 286 00:13:22.360 --> 00:13:25.759 Pressure, and Chuck Miller finds the fatal flaw in those latches. 287 00:13:25.840 --> 00:13:26.200 He does. 288 00:13:26.559 --> 00:13:29.039 Baggage handlers on the ground had to close a lever 289 00:13:29.159 --> 00:13:31.720 on the outside of the door to engage these locking pins, 290 00:13:32.240 --> 00:13:34.519 but the internal linkage was made of really thin. 291 00:13:34.440 --> 00:13:35.720 Metal, so it could bend. 292 00:13:36.120 --> 00:13:40.000 Yeah. If the pins didn't ligne perfectly, a baggage handler 293 00:13:40.039 --> 00:13:43.480 could physically force the exterior lever down, sometimes literally using 294 00:13:43.480 --> 00:13:47.279 their knee for leverage and bend the internal metal rod, and. 295 00:13:47.240 --> 00:13:50.080 The lever would sit flush on the outside, making it look. 296 00:13:49.919 --> 00:13:53.759 Locked exactly and even worse, forcing the handle triggered the 297 00:13:53.799 --> 00:13:56.399 electronic sensor to turn off the warning light in the cockpit, 298 00:13:56.840 --> 00:13:59.399 so the pilot's instruments told them it was locked, but 299 00:13:59.440 --> 00:14:02.799 the door was essentially a ticking time bomb. 300 00:14:02.960 --> 00:14:06.759 And this explains the collapsed floor perfectly. An airplane cabin 301 00:14:06.879 --> 00:14:09.320 is pumped full of pressurized air so you can breathe. 302 00:14:09.960 --> 00:14:13.279 The cargo hold below is also pressurized, right, But when 303 00:14:13.279 --> 00:14:15.799 that cargo door bleue open, the pressure in the hold 304 00:14:15.919 --> 00:14:19.000 instantly vanished, So you suddenly had a cabin full of 305 00:14:19.039 --> 00:14:22.600 high pressure air sitting directly above a low pressure hole. 306 00:14:22.720 --> 00:14:24.120 So the air just rushes down. 307 00:14:24.240 --> 00:14:27.320 Yes, the air rapidly sought the exit, and the sheer 308 00:14:27.360 --> 00:14:30.960 force of that pressure equalization crushed the passenger floor downward, 309 00:14:31.279 --> 00:14:32.879 taking all those control cables with it. 310 00:14:32.960 --> 00:14:36.519 Okay, So the NTSB discovers this catastrophic mechanical flaw and 311 00:14:36.559 --> 00:14:39.320 the vulnerability of the floor in nineteen seventy two. My 312 00:14:39.399 --> 00:14:41.759 immediate thought is like, if I buy a new car, 313 00:14:41.879 --> 00:14:44.720 and the manufacturer finds out the brake lines can easily snap. 314 00:14:44.960 --> 00:14:46.799 There is a mandatory recall. 315 00:14:47.000 --> 00:14:48.200 Right, you ground the cars. 316 00:14:48.679 --> 00:14:52.039 Yeah, the FAA has the power to issue an airworthiness 317 00:14:52.039 --> 00:14:55.440 directive which legally forces all DC tens out of the 318 00:14:55.480 --> 00:14:57.399 sky until the locks and floors are fixed. 319 00:14:57.559 --> 00:15:01.159 And the NTSB strongly recommended the f do exactly that. 320 00:15:01.279 --> 00:15:02.519 But they didn't know. 321 00:15:03.240 --> 00:15:05.360 We have to look at the economic reality at the 322 00:15:05.399 --> 00:15:09.159 aviation industry at the time. Grounding a brand new billion 323 00:15:09.200 --> 00:15:12.919 dollar fleet of aircraft overnight would have crippled airlines and 324 00:15:12.960 --> 00:15:15.159 sent shockwaves through the global economy. 325 00:15:15.200 --> 00:15:17.200 So what do they do instead? Just let them fly? 326 00:15:17.600 --> 00:15:21.519 They engaged in what investigators later bitterly referred to as 327 00:15:21.720 --> 00:15:22.919 a gentleman's agreement. 328 00:15:23.200 --> 00:15:24.200 Oh that's sound shady. 329 00:15:24.320 --> 00:15:26.960 It was the head of the FAA and the president 330 00:15:26.960 --> 00:15:31.159 of McDonald douglas made a backroom deal. An airworthiness directive 331 00:15:31.159 --> 00:15:33.799 would have been a pr nightmare for McDonald douglas, who 332 00:15:33.879 --> 00:15:36.679 was locked in a fierce existential sales war against Boeing 333 00:15:36.720 --> 00:15:37.279 and Lockheed. 334 00:15:37.399 --> 00:15:39.320 Ah, so it was about money totally. 335 00:15:39.639 --> 00:15:42.919 So McDonald douglas promised to implement a fix voluntarily during 336 00:15:43.000 --> 00:15:46.840 routine maintenance, and the FAA agreed not to ground the planes. 337 00:15:46.559 --> 00:15:49.120 A voluntary fix for a door that blew off in midair. 338 00:15:49.159 --> 00:15:51.759 I'm sorry, but that is just infuriating, it really is, 339 00:15:52.039 --> 00:15:55.519 and it leads right into the tragedy. Two years later, 340 00:15:55.919 --> 00:16:00.639 March nineteen seventy four, Turkish Airlines Flight ninety one takes 341 00:16:00.639 --> 00:16:03.840 off from Paris. It's packed with three hundred and forty. 342 00:16:03.559 --> 00:16:05.879 Six people and we know what happens next. 343 00:16:06.000 --> 00:16:08.759 As it climbs through eleven thousand feet, the exact same 344 00:16:08.799 --> 00:16:13.080 cargo door with the exact same bent locking mechanism blows off. 345 00:16:13.279 --> 00:16:14.720 The floor collapses again. 346 00:16:14.840 --> 00:16:15.799 But this time it's worse. 347 00:16:15.879 --> 00:16:19.039 Yeah. This time, the collapsing floor severs all the redundant 348 00:16:19.080 --> 00:16:19.919 hydraulic lines. 349 00:16:19.960 --> 00:16:23.159 And without hydraulics, the crew had absolutely no way to 350 00:16:23.200 --> 00:16:26.559 move the flight control surfaces. Differential thrust just couldn't save. 351 00:16:26.440 --> 00:16:28.039 Them, so they were totally helpless. 352 00:16:28.080 --> 00:16:31.639 Completely. The plane pitched down, accelerated to five hundred miles 353 00:16:31.679 --> 00:16:34.799 per hour, and crashed into a forest outside Paris. It 354 00:16:34.879 --> 00:16:37.720 was the worst plane crash in aviation history at the time. 355 00:16:38.000 --> 00:16:40.679 When Chuck Miller from the NTSB went to France and 356 00:16:40.720 --> 00:16:43.320 looked at the wreckage, he must have been absolutely sick 357 00:16:43.360 --> 00:16:44.000 to his stomach. 358 00:16:44.080 --> 00:16:45.759 I can't even imagine. 359 00:16:45.279 --> 00:16:48.720 The voluntary fixes that McDonald douglas's promise. They were pathetic. 360 00:16:48.759 --> 00:16:51.480 They literally just added a tiny people for baggage handlers 361 00:16:51.480 --> 00:16:53.720 to physically look and see if the pins were engaged. 362 00:16:54.080 --> 00:16:56.039 But they didn't even explain what to look for. 363 00:16:56.399 --> 00:16:58.720 And the warning signs were written only in English. 364 00:16:59.000 --> 00:17:04.039 Right, baggage handler who closed the door spoke three languages, 365 00:17:04.359 --> 00:17:05.839 but none of them were English. 366 00:17:06.279 --> 00:17:10.240 The fallout from this was just monumental. During the massive 367 00:17:10.319 --> 00:17:14.200 lawsuits that followed, a journalist named Paul Eddie uncovered a 368 00:17:14.240 --> 00:17:15.839 document that changed everything. 369 00:17:15.960 --> 00:17:17.920 The Applegate Memo, yes. 370 00:17:17.759 --> 00:17:20.359 It became known as the Applegate Memo, was written by 371 00:17:20.440 --> 00:17:24.880 Don Applegate, the director of product engineering for Conveyor. They 372 00:17:24.880 --> 00:17:28.079 were the subcontractor that actually built the fuselage doors for 373 00:17:28.200 --> 00:17:29.160 McDonald douglas. 374 00:17:29.240 --> 00:17:31.799 And tell me the timeline of when this memo was written, 375 00:17:31.839 --> 00:17:33.440 because this is the part that just haunts me. 376 00:17:33.920 --> 00:17:37.519 Applegate wrote this memo just weeks after the first Windsor 377 00:17:37.519 --> 00:17:39.240 incident in nineteen seventy two. 378 00:17:39.279 --> 00:17:41.640 Wow, two years before Paris exactly. 379 00:17:42.160 --> 00:17:45.960 He explicitly warned his superiors that the outward opening door 380 00:17:46.240 --> 00:17:50.000 and the unvented floor above. It created an inherent susceptibility 381 00:17:50.039 --> 00:17:51.480 to catastrophic. 382 00:17:50.880 --> 00:17:53.039 Failure, so he knew exactly what was going to happen. 383 00:17:53.160 --> 00:17:56.079 He quite literally predicted that an airplane would be lost 384 00:17:56.359 --> 00:17:59.200 and a major disaster would occur if they didn't fundamentally 385 00:17:59.200 --> 00:17:59.960 redesign this aste. 386 00:18:00.440 --> 00:18:02.880 So they knew, They absolutely knew, and they pushed it 387 00:18:02.880 --> 00:18:06.200 through anyway because of the bottom line. During the trial, 388 00:18:06.359 --> 00:18:09.359 evidence actually came out that the cargo door had failed 389 00:18:09.599 --> 00:18:13.400 during a ground pressure test four years before the Paris crash. 390 00:18:13.799 --> 00:18:18.119 The industry later coined a term for this tombstone technology. 391 00:18:18.319 --> 00:18:22.640 It's such a dark it's this dark pragmatic calculus where 392 00:18:22.680 --> 00:18:27.160 a manufacturer essentially waits for enough people to die before 393 00:18:27.200 --> 00:18:30.359 the lawsuits cost more than simply spending the money to 394 00:18:30.400 --> 00:18:32.720 fix a hazard they already knew about, and. 395 00:18:32.640 --> 00:18:36.200 It ultimately cost McDonald douglas over eighty million dollars in damages. 396 00:18:36.720 --> 00:18:40.680 The FAA finally issued the legally binding airworthiness directive to 397 00:18:40.759 --> 00:18:43.680 fundamentally redesign the doors and vent the cabin. 398 00:18:43.440 --> 00:18:47.119 Floors, but their reputational damage was terminal, and McDonald douglas 399 00:18:47.160 --> 00:18:50.319 never fully recovered its dominance. No, they didn't, okay, so 400 00:18:50.359 --> 00:18:53.160 we've moved from the unpredictable forces of nature in our 401 00:18:53.200 --> 00:18:56.960