WEBVTT 1 00:00:00.160 --> 00:00:04.360 So I want you to picture this. Yeah, it is 2 00:00:04.360 --> 00:00:06.960 December twenty seventh, nineteen ninety one. You're sitting at the 3 00:00:07.000 --> 00:00:10.039 cockpit of a state of the art sixty ton McDonald 4 00:00:10.039 --> 00:00:11.039 Douglas DC. 5 00:00:10.960 --> 00:00:14.000 Nine oh man, a total classic aircraft, right. 6 00:00:13.960 --> 00:00:16.480 And you're at an altitude of about three two hundred feet. 7 00:00:16.920 --> 00:00:19.839 Just seconds ago, you know, you're climbing into this really 8 00:00:19.920 --> 00:00:24.440 bitter winter sky over Sweden. But right now your reality 9 00:00:24.519 --> 00:00:27.920 is defined by this violent, just deafening roar. 10 00:00:27.920 --> 00:00:31.000 Because the engines are just violently shaking the entire airframe 11 00:00:31.000 --> 00:00:32.159 at this point exactly. 12 00:00:32.200 --> 00:00:34.960 And you can smell it too, that sharp, acrid scent 13 00:00:35.039 --> 00:00:37.719 of electrical smoke. It's just bleeding through the air vents. 14 00:00:37.880 --> 00:00:41.039 And then suddenly you hear the most terrifying sound in all. 15 00:00:40.880 --> 00:00:43.079 Of aviation, total absolute silence. 16 00:00:43.159 --> 00:00:46.320 Yeah, the engines are completely dead. That roaring vibration is 17 00:00:46.359 --> 00:00:49.520 just instantly replaced by this eerie, hollow, rushing sound of 18 00:00:49.560 --> 00:00:49.880 the wind. 19 00:00:49.920 --> 00:00:52.399 I mean, in a fraction of a second, this massive 20 00:00:52.479 --> 00:00:55.799 passenger jet has just become a powerless glider. It is 21 00:00:55.920 --> 00:00:58.280 dropping out of the sky at twenty feet per second. 22 00:00:58.479 --> 00:01:02.119 It's truly a nightmare scenario. And when you sent over 23 00:01:02.159 --> 00:01:05.680 this stack of raw flight data, you know, the transcripts 24 00:01:05.719 --> 00:01:09.519 and the forensic field notes regarding Scandinavian Airlines flight seven 25 00:01:09.640 --> 00:01:13.239 fifty one, our mission for today became really clear. 26 00:01:13.439 --> 00:01:16.200 Oh absolutely, we are pulling up a chair and acting 27 00:01:16.239 --> 00:01:19.439 as real life aviation accident investigators for this one. 28 00:01:19.480 --> 00:01:22.159 We really are. We're going to reconstruct a moment in 29 00:01:22.280 --> 00:01:26.159 history that completely defied the laws of logic. So pull 30 00:01:26.239 --> 00:01:28.439 up a chair, sit across the desk with us, and 31 00:01:28.560 --> 00:01:32.280 let's look at the facts. Because there is no journalistic 32 00:01:32.400 --> 00:01:33.519 dryness here today. 33 00:01:33.760 --> 00:01:37.480 No, definitely not. This is a very visceral story of survival, 34 00:01:37.799 --> 00:01:41.239 the terrifying laws of physics, and well quite literally a 35 00:01:41.280 --> 00:01:42.159 ghost in the machine. 36 00:01:42.280 --> 00:01:45.159 Yeah, here's where it gets really interesting. We're looking at 37 00:01:45.159 --> 00:01:47.760 a flight crew that did absolutely everything right. I mean, 38 00:01:47.799 --> 00:01:50.359 they followed their training to the letter, they executed every 39 00:01:50.439 --> 00:01:54.760 checklist flawlessly, and yet the plane's own hidden systems fundamentally 40 00:01:54.799 --> 00:01:55.359 betrayed them. 41 00:01:55.480 --> 00:01:58.519 Yeah, it's incredibly unsettling. But to understand the mechanics of 42 00:01:58.519 --> 00:02:01.079 how a pristine aircraft just falls out of the sky 43 00:02:01.239 --> 00:02:03.680 like that, we really need to examine the environment on 44 00:02:03.719 --> 00:02:04.879 the ground that morning. 45 00:02:04.719 --> 00:02:07.400 Right, because the weather was a huge factor huge factor. 46 00:02:07.840 --> 00:02:11.759 The conditions at Stockholm Orlanda Airport were to put it 47 00:02:11.800 --> 00:02:16.759 mildly miserable. You've got sleet, snow and slush just coming 48 00:02:16.800 --> 00:02:18.400 down in this freezing mix. 49 00:02:18.520 --> 00:02:21.280 Yeah, it's two days after Christmas, right, the temperature's hovering 50 00:02:21.360 --> 00:02:24.759 right around freezing. Yeah. But based on the cabin logs 51 00:02:24.800 --> 00:02:27.800 you provided in the source material inside this brand new 52 00:02:27.879 --> 00:02:31.439 DC nine, it is a completely different extreme. 53 00:02:31.520 --> 00:02:33.199 Oh, it's basically a sauna in there. 54 00:02:33.360 --> 00:02:37.080 Exactly the overnight ground crews had left the cabin heaters 55 00:02:37.240 --> 00:02:40.599 running full blast. So when these passengers step out of 56 00:02:40.599 --> 00:02:44.000 the freezing Swedish winter and start boarding, they are walking 57 00:02:44.039 --> 00:02:45.080 into a wall of heat. 58 00:02:45.360 --> 00:02:47.680 It is sweltering. I mean, you have passengers who are 59 00:02:47.759 --> 00:02:51.240 dressed for a heavy winter, thick coats, heavy boots, layers 60 00:02:51.280 --> 00:02:53.319 of scarves, and they are instantly sweating. 61 00:02:53.439 --> 00:02:55.039 Right, They're probably miserable, they are. 62 00:02:55.120 --> 00:02:57.879 People are immediately stripping off their winter jackets, throwing them 63 00:02:57.879 --> 00:03:00.360 into the overhead bins and just settling into the seats, 64 00:03:00.400 --> 00:03:03.000 wearing t shirts and light clothing just to escape the heat. 65 00:03:03.120 --> 00:03:05.599 Which you know, seems like a minor detail now, but 66 00:03:05.639 --> 00:03:07.639 that is going to become a literal matter of life 67 00:03:07.639 --> 00:03:08.520 and death later. 68 00:03:08.319 --> 00:03:11.719 On, it really is. Now. Meanwhile, up in the cockpit 69 00:03:11.960 --> 00:03:15.759 you have Captain Sten Rasmussen. He is a thirty four 70 00:03:15.840 --> 00:03:18.759 year veteran of the Skies, started in the Air Force 71 00:03:18.800 --> 00:03:20.199 before moving to commercial aviation. 72 00:03:20.400 --> 00:03:21.680 A very experienced guy. 73 00:03:21.680 --> 00:03:25.280 Fairy, and he genuinely loves his job. He even has 74 00:03:25.319 --> 00:03:27.800 this quirk where he insists on flying with the cockpit 75 00:03:27.840 --> 00:03:30.000 door open just so the passengers can see the crew. 76 00:03:30.639 --> 00:03:32.280 He really wants that human connection. 77 00:03:32.520 --> 00:03:33.639 That's actually really nice. 78 00:03:33.759 --> 00:03:37.439 Yeah, But above all else he is incredibly meticulous about safety. 79 00:03:37.879 --> 00:03:40.919 Seeing the miserable weather outside, he orders the ground crew 80 00:03:40.960 --> 00:03:43.479 to de ice the wings not just once, but twice. 81 00:03:43.599 --> 00:03:45.520 Okay, Wait, I gotta stop you right there and just 82 00:03:45.759 --> 00:03:47.879 push back on this a little bit, okay, because I 83 00:03:47.960 --> 00:03:50.120 was looking at these ground logs and the materials you 84 00:03:50.159 --> 00:03:53.800 sent over and I'm genuinely lost here. How so, Well, 85 00:03:53.800 --> 00:03:56.120 if he ordered a double the icing and they blasted 86 00:03:56.120 --> 00:03:58.879 the plane with what over eight hundred and fifty liters 87 00:03:58.879 --> 00:04:03.360 of chemical fluid and a trained technician physically looked at 88 00:04:03.360 --> 00:04:06.000 the wing and signed the release saying it was clean, 89 00:04:06.759 --> 00:04:08.960 how on earth did ice bring this plane down? 90 00:04:09.479 --> 00:04:12.680 It's a great question. And what's fascinating Here is the 91 00:04:12.680 --> 00:04:16.160 fatal physics of how the aircraft spent the previous night. 92 00:04:17.240 --> 00:04:20.240 The plane had arrived from Zurich the evening before, and 93 00:04:20.279 --> 00:04:22.920 it arrived with its wing tanks more than half full 94 00:04:22.959 --> 00:04:23.839 of reserve fuel. 95 00:04:23.920 --> 00:04:25.680 Okay, so he had a lot of fuel left. 96 00:04:25.439 --> 00:04:27.959 Over, right, And because they had been cruising at high 97 00:04:28.000 --> 00:04:31.600 altitude for hours, that aviation fuel was cold soaked. It 98 00:04:31.680 --> 00:04:35.160 was sitting at a core temperature of negative twenty degrees celsius. 99 00:04:35.279 --> 00:04:39.199 Wow. So those fuel tanks, which are structurally built right 100 00:04:39.199 --> 00:04:43.319 into the wings, they're basically acting like massive negative twenty 101 00:04:43.319 --> 00:04:46.439 degree ice packs pushed right up against the aluminum. 102 00:04:46.000 --> 00:04:49.839 Skin exactly that. The superchilled fuel cooled the upper metal 103 00:04:49.879 --> 00:04:53.920 skin of the wings to well below freezing through conductive cooling. 104 00:04:54.519 --> 00:04:57.160 So as the plane sat parked on the tarmac overnight, 105 00:04:57.439 --> 00:04:58.120 this weather. 106 00:04:57.920 --> 00:04:59.519 Front moved in the rain and the sleep. 107 00:04:59.639 --> 00:05:02.720 Yeah, it rained, it sleated, and then it snowed, and 108 00:05:02.759 --> 00:05:05.480 this created a deadly layer cake effect on the top 109 00:05:05.519 --> 00:05:08.240 of the wings at the very bottom right against the 110 00:05:08.240 --> 00:05:11.800 freezing aluminum. The moisture froze from the bottom up. It 111 00:05:11.879 --> 00:05:14.720 formed this thick layer of solid, clear. 112 00:05:14.560 --> 00:05:17.319 Ice Okay, And then on top of that clear ice 113 00:05:17.600 --> 00:05:19.720 sat the slush and the visible. 114 00:05:19.360 --> 00:05:22.480 Snow precisely so when the d icing trucks came around 115 00:05:22.480 --> 00:05:25.240 in the morning, the hot fluid melted all the visible 116 00:05:25.279 --> 00:05:29.199 snow and slush on that top layer. The fluid sheared off, 117 00:05:29.319 --> 00:05:31.920 so the wing looked wet and perfectly. 118 00:05:31.439 --> 00:05:35.639 Clean, but that bottom layer of clear ice remained completely 119 00:05:35.680 --> 00:05:37.040 bonded to the freezing metal. 120 00:05:37.240 --> 00:05:41.680 Yes, it was perfectly transparent, completely invisible to the naked 121 00:05:41.720 --> 00:05:44.959 eye under the wet fluid, and because the airline didn't 122 00:05:45.000 --> 00:05:47.439 require the mechanics to use a ladder to climb up 123 00:05:47.480 --> 00:05:49.879 and physically touch the top of the wing, that clear 124 00:05:49.920 --> 00:05:51.839 ice was just completely miss man. 125 00:05:51.959 --> 00:05:55.720 That is chilling, literally, So they are cleared for takeoff 126 00:05:55.839 --> 00:05:58.079 with a hidden solid sheet of ice clinging to the 127 00:05:58.079 --> 00:05:58.600 wing roots. 128 00:05:58.720 --> 00:06:01.920 That's right. As they taxed out, the first officer ULF 129 00:06:01.959 --> 00:06:05.720 seater runs through the final checklists. Everything is green. The 130 00:06:05.759 --> 00:06:08.600 engines spool up and the plane accelerates down the runway, 131 00:06:08.879 --> 00:06:09.240 and the. 132 00:06:09.160 --> 00:06:13.079 Takeoff roll is completely routine. But the moment the aircraft 133 00:06:13.079 --> 00:06:16.360 lifts off the ground, the aerodynamics change dramatically, don't they 134 00:06:16.759 --> 00:06:17.120 They do. 135 00:06:18.000 --> 00:06:21.319 As the massive plane leaves the runway, the wings naturally 136 00:06:21.360 --> 00:06:24.160 flex and bend upward to take the sixty ton weight 137 00:06:24.199 --> 00:06:25.240 of the aircraft. 138 00:06:24.920 --> 00:06:26.199 Right, they have to support all that. 139 00:06:26.120 --> 00:06:29.560 Weight exactly, And the dihedral flex of the DC nine 140 00:06:29.600 --> 00:06:33.920 wing acts exactly like twisting a plastic ice tray. That 141 00:06:34.040 --> 00:06:36.959 invisible sheet of clear ice on the wing roots just 142 00:06:37.079 --> 00:06:38.879 shatters under the structural tension. 143 00:06:38.959 --> 00:06:41.360 Oh man, like an ice tray. That's such a perfect 144 00:06:41.360 --> 00:06:42.040 way to picture it. 145 00:06:42.199 --> 00:06:45.240 Yeah, And so these chunks of solid ice break loose 146 00:06:45.279 --> 00:06:49.079 and slides straight back off the aerodynamic surface of the wings. Now, 147 00:06:49.120 --> 00:06:51.560 on most commercial jets, where the engines are mounted beneath 148 00:06:51.560 --> 00:06:53.800 the wings, this wouldn't be a catastrophe, right, they just 149 00:06:53.800 --> 00:06:57.800 fall away exactly. But the DC nine features two engines 150 00:06:57.839 --> 00:07:00.439 mounted at the rear of the fuselage. 151 00:07:00.079 --> 00:07:03.079 Right in the firing line. So the shattered ice slides 152 00:07:03.120 --> 00:07:05.839 off the trailing edge of the wings and is inhaled 153 00:07:05.879 --> 00:07:08.079 directly into both rear engine collings. 154 00:07:08.199 --> 00:07:09.920 It's a worst case scenario, and. 155 00:07:09.839 --> 00:07:13.120 At exactly twenty five seconds into the flight, the passengers 156 00:07:13.120 --> 00:07:16.639 and the crew hear it a massive, violent boom, you know. 157 00:07:16.759 --> 00:07:19.519 One survivor in the nose described the sheer concussive force 158 00:07:19.560 --> 00:07:22.800 as sounding like a bomb detonating inside the cabin. 159 00:07:23.160 --> 00:07:25.879 I can't even imagine how terrifying that must have been. 160 00:07:26.199 --> 00:07:30.000 The aircraft starts violently shaking, and then another bang follows. 161 00:07:30.199 --> 00:07:32.839 Right. Because the fan blades at the very front of 162 00:07:32.879 --> 00:07:37.160 the jet engines are spinning at thousands of revolutions per minute. 163 00:07:37.319 --> 00:07:40.959 When solid ice impacts them at those speeds, the titanium 164 00:07:41.000 --> 00:07:44.519 blades become dented, They warp, and they physically. 165 00:07:44.040 --> 00:07:46.000 Deform, so they can't do their job anymore. 166 00:07:46.120 --> 00:07:49.519 Exactly. They can no longer cleanly slice through the air 167 00:07:49.639 --> 00:07:53.439 to push it backward into the compressor stages. This creates 168 00:07:53.439 --> 00:07:57.639 a catastrophic disruption in the high pressure airflow, which leads 169 00:07:57.680 --> 00:07:59.040 to a compressor surge. 170 00:07:59.279 --> 00:08:01.959 Okay, the impact this for a second, because a compressor search. 171 00:08:02.199 --> 00:08:03.720 It makes sense if you think about it like an 172 00:08:03.759 --> 00:08:05.800 Olympic sprinter running it all out dash. 173 00:08:06.079 --> 00:08:07.319 Okay, I like that analogy. 174 00:08:07.399 --> 00:08:10.800 Yeah, So the runner is gasping for air, right, breathing heavily. 175 00:08:11.160 --> 00:08:13.519 If someone suddenly clamps a hand over their mouth, the 176 00:08:13.560 --> 00:08:14.600 whole system. 177 00:08:14.360 --> 00:08:17.959 Just jokes, right, They can't get the oxygen they need exactly. 178 00:08:18.560 --> 00:08:22.519 Jet engines work by continuously sucking in air, compressing it, 179 00:08:22.920 --> 00:08:25.879 mixing it with fuel and igniting it to shoot out 180 00:08:25.920 --> 00:08:29.000 the back. But when those front blades are warped, it's 181 00:08:29.000 --> 00:08:31.959 like clanning a hand over the intake. The continuous airflow 182 00:08:32.000 --> 00:08:32.799 breaks down. 183 00:08:32.679 --> 00:08:34.559 And that's when things get really violent. 184 00:08:34.399 --> 00:08:37.559 Right, because the incredibly high pressure air and ignited fuel 185 00:08:37.600 --> 00:08:40.799 from the combustion chamber in the back, it violently backfires 186 00:08:40.840 --> 00:08:42.720 and shoots forward out the front of the engine. 187 00:08:42.840 --> 00:08:46.840 It is an incredibly destructive event. And Captain Rasmussen recognizes 188 00:08:46.879 --> 00:08:49.919 the acoustic signature immediately. He knows his engines are surging. 189 00:08:50.519 --> 00:08:54.279 So he does exactly what decades of aviation training and 190 00:08:54.320 --> 00:08:56.639 simulator drills have hardwired. 191 00:08:56.159 --> 00:08:58.159 Him to do, which is to pull back on the 192 00:08:58.200 --> 00:08:59.360 throttle right exactly. 193 00:08:59.759 --> 00:09:02.799 The buy the book procedure for a compressor surge is 194 00:09:02.840 --> 00:09:04.840 to pull back on the throttle. You have to reduce 195 00:09:04.840 --> 00:09:07.519 the fuel flow to allow the engine to catch its breath, 196 00:09:07.879 --> 00:09:10.559 match the disrupted airflow, and stabilize. 197 00:09:10.799 --> 00:09:13.600 But looking at the flight data recorder trace you provided, 198 00:09:14.240 --> 00:09:17.159 this is where it gets absolutely crazy. Rasmusen pulls the 199 00:09:17.240 --> 00:09:20.519 right throttle back, but the engine doesn't slow down, No, 200 00:09:20.600 --> 00:09:24.519 it doesn't. Instead, the engine's rpm starts accelerating on its own. 201 00:09:25.000 --> 00:09:28.440 He is pulling the throttle lever physically back toward him, 202 00:09:28.679 --> 00:09:31.519 and the engines are just whining louder and louder. He 203 00:09:31.600 --> 00:09:35.360 reduces the throttle again, and the engine pumps even more power. 204 00:09:35.759 --> 00:09:38.399 It's an unexplainable phenomenon in the moment. I mean, he 205 00:09:38.480 --> 00:09:41.000 is pulling back, but the engine is acting as if 206 00:09:41.000 --> 00:09:43.639 the throttle is being shoved all the way to the firewall. 207 00:09:43.720 --> 00:09:45.759 It's doing the exact opposite of what he's telling it 208 00:09:45.799 --> 00:09:46.000 to do. 209 00:09:46.200 --> 00:09:49.919 Exactly. The engine is choking, it's starving for oxygen, and 210 00:09:50.000 --> 00:09:53.559 yet it is being flooded with maximum fuel. It literally 211 00:09:53.600 --> 00:09:56.519 begins tearing itself apart from the inside out under the 212 00:09:56.519 --> 00:09:58.080 thermal and mechanical stress. 213 00:09:58.240 --> 00:10:01.360 And just ninety seconds into the flight, first officer Seater 214 00:10:01.600 --> 00:10:04.519 sees the exhaust gas temperature gauge for the left engine 215 00:10:04.759 --> 00:10:08.879 skyrockets past eight hundred degrees celsius. Smoke is pouring into 216 00:10:08.919 --> 00:10:09.759 the passenger cabin. 217 00:10:09.799 --> 00:10:11.000 It's a full blown emergency. 218 00:10:11.039 --> 00:10:14.200 Now, yeah, the left engine is officially on fire. Seat 219 00:10:14.279 --> 00:10:18.039 makes a split second, just agonizing decision. He reaches up 220 00:10:18.080 --> 00:10:21.000 and pulls the fire extinguisher handle for the left engine. 221 00:10:20.559 --> 00:10:23.159 Which you know is the absolute right call to save 222 00:10:23.399 --> 00:10:25.879 the wing structure from melting off. But it's a permanent action. 223 00:10:26.240 --> 00:10:29.360 Once you pull that fire handle, you sever all fuel 224 00:10:29.399 --> 00:10:33.000 lines and hydraulics at the firewall. That engine is dead 225 00:10:33.039 --> 00:10:34.840 and cannot be restarted in the air. 226 00:10:34.960 --> 00:10:37.799 Right, it's a one way street. So the left engine dies, 227 00:10:38.559 --> 00:10:43.080 and then two seconds later, the severely overstressed right engine 228 00:10:43.519 --> 00:10:47.240 violently gives up and dies too. Total structural failure. 229 00:10:46.960 --> 00:10:49.639 And that brings us to that terrifying silence we talked about. 230 00:10:49.840 --> 00:10:52.320 Yeah, they are three two hundred feet in the air, 231 00:10:52.399 --> 00:10:54.480 just dropping like a stone. 232 00:10:54.279 --> 00:10:58.480 And the cockpit is instantly plunged into a cascading secondary crisis. 233 00:10:59.000 --> 00:11:02.080 Losing both engines means they instantly lose the main engine 234 00:11:02.159 --> 00:11:05.320 driven generators, So this is power total electrical failure. The 235 00:11:05.320 --> 00:11:08.559 electrical buses die, the primary flight instruments freeze in place, 236 00:11:09.080 --> 00:11:12.320 the radios to air traffic control go completely dark. They're 237 00:11:12.399 --> 00:11:16.200 essentially flying blind, deaf, and powerless. 238 00:11:15.799 --> 00:11:19.559 And First Officer Sedter is frantically running through emergency checklists, 239 00:11:19.559 --> 00:11:21.960 you know, trying to force the engines to restart, but 240 00:11:22.039 --> 00:11:24.639 it's utterly futile. The engines are basically chewed to pieces. 241 00:11:24.759 --> 00:11:29.080 Yeah they're gone, but at this exact moment. Captain Perl Holmberg, 242 00:11:29.279 --> 00:11:31.559 another pilot who just happened to be commuting as a 243 00:11:31.600 --> 00:11:34.679 passenger on this flight. He rushes into the cockpit right. 244 00:11:34.519 --> 00:11:37.639 He's sitting in the cabin here's the explosions, feels the 245 00:11:37.679 --> 00:11:41.200 negative G force of the drop and immediately unbuckles. He 246 00:11:41.399 --> 00:11:44.279 bursts through that open cockpit door, looks at the dark 247 00:11:44.320 --> 00:11:48.240 instrument panels, reaches right over Rasmussen's shoulder without saying a word, 248 00:11:48.480 --> 00:11:51.440 and blindly hits the switch to start the APU. 249 00:11:51.360 --> 00:11:54.440 The auxiliary power unit and the tail exactly. 250 00:11:54.120 --> 00:11:58.000 And it takes vital agonizing seconds to spool up. But 251 00:11:58.080 --> 00:12:01.039 when it does, it restores justin off electrical power to 252 00:12:01.080 --> 00:12:04.799 bring the primary flight displays and the radios back online. 253 00:12:04.879 --> 00:12:07.919 So air traffic Control finally reconnects with them. And I 254 00:12:08.039 --> 00:12:10.919 was reading the ATC transcripts here, and the controller immediately 255 00:12:10.960 --> 00:12:13.159 instructs them to make a one hundred and eighty degree turn. 256 00:12:13.399 --> 00:12:16.440 They head back to the runway at ORLANDA, but Rasmussen 257 00:12:16.519 --> 00:12:17.960 completely ignores the order. 258 00:12:18.279 --> 00:12:21.000 And if we connect this to the bigger picture of aerodynamics, 259 00:12:21.320 --> 00:12:24.799 Rasmusen's refusal to turn is the single decision that saves 260 00:12:24.840 --> 00:12:28.559 their lives really how so well, when you are flying 261 00:12:28.559 --> 00:12:32.600 a heavy, unpowered aircraft, your altitude is your only currency. 262 00:12:33.279 --> 00:12:36.120 If you bank a sixty ton glider into a sharp turn, 263 00:12:36.519 --> 00:12:39.440 you increase the load factor on the wings and create 264 00:12:39.639 --> 00:12:41.399 massive aerodynamic drag. 265 00:12:41.519 --> 00:12:43.279 Oh I see, you lose your speed right. 266 00:12:43.159 --> 00:12:47.679 You bleed away that precious kinetic energy exponentially. If he 267 00:12:47.720 --> 00:12:50.120 had tried to turn that plane around at low altitude, 268 00:12:50.480 --> 00:12:53.639 the wings would have lost their lift, aircraft would have stalled, 269 00:12:53.639 --> 00:12:55.679 and they would have dropped straight down like a rock. 270 00:12:55.919 --> 00:12:58.000 He knew he had to keep the wings perfectly level 271 00:12:58.200 --> 00:13:00.360 and manage his glide path straight ahead, So. 272 00:13:00.399 --> 00:13:02.399 He is aiming for what he thinks is a clearing 273 00:13:02.440 --> 00:13:05.279 on the horizon, which he thinks is the frozen Baltic Sea, 274 00:13:05.799 --> 00:13:08.360 because ditching on a flatshet of ice is obviously a 275 00:13:08.440 --> 00:13:11.240 much better option than what's immediately below them, much better. 276 00:13:11.399 --> 00:13:14.200 But as they drop below one thousand feet, the cloud 277 00:13:14.279 --> 00:13:17.840 layer breaks the visual clears, and his heart just sinks. 278 00:13:18.320 --> 00:13:23.200 It's not the sea. It's a dense, unforgiving Swedish pine forest. 279 00:13:23.159 --> 00:13:26.440 And there is nowhere else to go. Captain Holmberg is 280 00:13:26.480 --> 00:13:28.919 standing right behind the pilots, screaming at them to look 281 00:13:28.960 --> 00:13:32.399 straight ahead, focusing their visual field entirely on the flight 282 00:13:32.480 --> 00:13:34.240 path so they don't fixate on the ground. 283 00:13:34.399 --> 00:13:37.000 And meanwhile in the back, the cabin crew has the 284 00:13:37.000 --> 00:13:41.360 passengers braced heads between their knees, just waiting for the impact. 285 00:13:41.440 --> 00:13:44.639 At just five hundred feet above the ground, Rasmussen makes 286 00:13:44.639 --> 00:13:47.799 his final brilliant move. He hauls back on the yoke 287 00:13:47.879 --> 00:13:49.840 to flare the nose of the aircraft up. 288 00:13:50.000 --> 00:13:52.639 He's intentionally trying to bleed off as much airspeed as. 289 00:13:52.519 --> 00:13:56.000 Possible yeah exrectly increasing the angle of attack and essentially 290 00:13:56.159 --> 00:13:59.399 using the dense canopy of pine trees as a giant 291 00:13:59.480 --> 00:14:02.519 kinetic energy dissipator like a forest pillow. 292 00:14:02.600 --> 00:14:05.240 And the impact is brutal. The plane rips through the 293 00:14:05.240 --> 00:14:09.320 tree tops, shearing the right wing completely off. It smashes 294 00:14:09.360 --> 00:14:11.919 into the forest floor, plowing through one hundred and twenty 295 00:14:11.919 --> 00:14:14.039 five meters of snow, dirt and timber. 296 00:14:14.200 --> 00:14:17.759 The sheer violent force snaps the fuselage into three separate, 297 00:14:18.000 --> 00:14:20.120 jagged pieces before grinding to a halt. 298 00:14:20.519 --> 00:14:24.720 And inside the wreckage it is just pure chaos. The 299 00:14:24.799 --> 00:14:29.159 smell of highly flammable jet fuel is overpowering. People are terrified. 300 00:14:29.159 --> 00:14:31.759 The plane is going to explode. And remember those passengers, 301 00:14:31.759 --> 00:14:33.519 the ones who stripped down to their t shirts because 302 00:14:33.559 --> 00:14:34.519 the cabin was a sauna. 303 00:14:34.679 --> 00:14:36.519 Yeah, they're not dressed for this, not at all. 304 00:14:36.960 --> 00:14:41.080 They are now scrambling out of the cracked fuselage directly 305 00:14:41.159 --> 00:14:42.960 into the freezing Swedish snow. 306 00:14:43.159 --> 00:14:46.120 First responders arrive within minutes, and they are expecting a 307 00:14:46.159 --> 00:14:48.840 total loss of life. Yeah, I mean, looking at the wreckage, 308 00:14:48.879 --> 00:14:49.919 how could anyone survive? 309 00:14:50.080 --> 00:14:52.120 Right? It looks completely unsurvivable. 310 00:14:52.159 --> 00:14:54.559 But as they start pulling people from the wreckage and 311 00:14:54.600 --> 00:14:57.480 the crew conducts a frantic headcount, they are met with 312 00:14:57.559 --> 00:15:00.559 a completely impossible reality. Out of of the one hundred 313 00:15:00.559 --> 00:15:03.399 and twenty nine people who boarded flight seven fifty one, 314 00:15:03.720 --> 00:15:07.799 there are zero fatalities. Wow, every single person survived the impact. 315 00:15:08.000 --> 00:15:12.639 It's genuinely miraculous. The media, of course, immediately dubs Rasmusen 316 00:15:12.720 --> 00:15:15.519 the hero who landed a powerless jet in a forest. 317 00:15:15.960 --> 00:15:19.000 But for the crash investigators arriving on the scene, there's 318 00:15:19.080 --> 00:15:20.159 no time for celebration. 319 00:15:20.279 --> 00:15:20.360 Now. 320 00:15:20.480 --> 00:15:22.440 They've a lot of work to do because they have 321 00:15:22.559 --> 00:15:26.879 a glaring, terrifying question to answer. How did a perfectly 322 00:15:26.919 --> 00:15:32.360 maintain modern airliner lose both engines simultaneously on a routine climb. 323 00:15:32.039 --> 00:15:35.519 Right, and the forensic investigation on the ground is incredibly painstaking. 324 00:15:35.559 --> 00:15:39.159 They map the entire fifteen kilometer flight path and send 325 00:15:39.200 --> 00:15:42.559 search teams into the snowy fields beneath the approach. 326 00:15:42.360 --> 00:15:43.480 And they find a lot of debris. 327 00:15:43.559 --> 00:15:48.039 Right they do. They recover over five hundred fragmented pieces 328 00:15:48.080 --> 00:15:50.480 of engine debris that had rained down from the sky 329 00:15:50.600 --> 00:15:53.519 before the crash, and what they find on the metallurgical 330 00:15:53.559 --> 00:15:56.279 analysis of those pieces is alarming because. 331 00:15:56.039 --> 00:15:58.879 Some of the titanium fan blades show clear evidence of 332 00:15:58.919 --> 00:16:00.120 having been on fire. 333 00:16:00.039 --> 00:16:03.320 Which is huge. A titanium fire is an incredibly rare, 334 00:16:03.399 --> 00:16:07.480 extraordinarily violent event. Titanium doesn't just catch fire easily. It 335 00:16:07.519 --> 00:16:11.879 requires immense sustained pressure and astronomical heat in an oxygen 336 00:16:11.960 --> 00:16:12.639 rich environment. 337 00:16:13.000 --> 00:16:14.639 So it's not a normal engine fire. 338 00:16:14.759 --> 00:16:17.440 Not at all. The fact that these blades were burning 339 00:16:17.519 --> 00:16:20.200 proved that the engines weren't just failing, they were combusting 340 00:16:20.320 --> 00:16:22.120 under massive, abnormal stress. 341 00:16:22.440 --> 00:16:25.440 But the real bombshell drops when the investigators pulled the 342 00:16:25.440 --> 00:16:29.360 flight data recorder, they are expecting the data to show 343 00:16:29.399 --> 00:16:32.840 that Captain Rasmussen recognized the compressor surge and pulled the 344 00:16:32.879 --> 00:16:35.960 throttles back, just like he claimed he did in his interviews, and. 345 00:16:35.919 --> 00:16:39.039 The FDR data does show that Rasmussen did pull the 346 00:16:39.039 --> 00:16:40.399 throttles back to idle. 347 00:16:40.639 --> 00:16:41.960 But then something else happens. 348 00:16:42.120 --> 00:16:45.120 Yeah, less than a second later, the flight data recorder 349 00:16:45.159 --> 00:16:48.159 shows the throttles being mechanically driven forward, not just a 350 00:16:48.200 --> 00:16:50.919 little bit either, shoved forward to one hundred and ten 351 00:16:50.960 --> 00:16:52.519 percent maximum. 352 00:16:52.000 --> 00:16:56.600 Power, pumping maximum fuel into engines that were already suffocated. Exactly, 353 00:16:57.080 --> 00:17:00.360 So what does this all mean. It's basically as if 354 00:17:00.399 --> 00:17:04.240 you're driving on a treacherous icy road, your car starts 355 00:17:04.279 --> 00:17:06.519 skidding out of control, you do the right thing and 356 00:17:06.519 --> 00:17:09.240 take your foot off the gas to regain traction, and 357 00:17:09.279 --> 00:17:13.079 your car's internal computer decides to just floor the accelerator instead. 358 00:17:13.440 --> 00:17:16.079 That's exactly what happened, and it makes absolutely no sense 359 00:17:16.119 --> 00:17:18.640 to the investigators. The only thing that should move those 360 00:17:18.640 --> 00:17:22.720 throttles is the pilot's physical hand. Ras Mussen swore he 361 00:17:22.720 --> 00:17:25.400 didn't push them forward. He said he felt them physically 362 00:17:25.440 --> 00:17:29.039 pulling away from him. So for two frustrating months, the 363 00:17:29.079 --> 00:17:33.079 investigation just hits a brick wall. They cannot figure out 364 00:17:33.119 --> 00:17:35.839 what commanded those engines to destroy themselves. 365 00:17:35.599 --> 00:17:39.119 Until the plane's manufacturer finally provides the missing puzzle piece. 366 00:17:40.359 --> 00:17:43.079 The culprit was a piece of software hidden deep within 367 00:17:43.119 --> 00:17:46.400 the plane's flight computers. It was a brand new feature 368 00:17:46.440 --> 00:17:50.319 called the Automatic Thrust Restoration System or ATR. 369 00:17:50.240 --> 00:17:53.440 Which raises a really important question. Why did this software 370 00:17:53.480 --> 00:17:54.759 even exist in the first place? 371 00:17:54.839 --> 00:17:55.960 Yeah, what was this purpose? 372 00:17:56.480 --> 00:17:59.559 Well, the manufacturer had recently designed the ATR system in 373 00:17:59.599 --> 00:18:04.000 response to strict noise abatement regulations from the Federal Aviation Administration. 374 00:18:04.480 --> 00:18:07.640 The FAA had noticed that some pilots were manually throttling 375 00:18:07.680 --> 00:18:10.559 back too much during takeoff to reduce engine noise over 376 00:18:10.640 --> 00:18:11.880 residential neighborhoods. 377 00:18:11.880 --> 00:18:16.319 Oh to be quiet, but that compromises the climb gradient exactly. 378 00:18:16.759 --> 00:18:19.799 To prevent this, the manufacturer coded the flight computer to 379 00:18:19.880 --> 00:18:22.880 monitor the RPM of the engines. If it detected the 380 00:18:22.920 --> 00:18:26.200 power dropping below a certain threshold during the climb phase, 381 00:18:26.680 --> 00:18:29.960 a servo motor would mechanically actuate the throttle cables and 382 00:18:30.039 --> 00:18:33.160 push them forward to ensure the plane kept climbing safely. 383 00:18:33.640 --> 00:18:36.640 And this is the ultimate betrayal of this entire story. 384 00:18:37.200 --> 00:18:39.759 Scandinavian Airlines didn't even buy this system. 385 00:18:39.839 --> 00:18:40.480 No, they didn't. 386 00:18:40.599 --> 00:18:43.640 They didn't escort it was secretly bundled into a larger, 387 00:18:43.799 --> 00:18:46.880 unrelated avionic software update for the aircraft. 388 00:18:47.160 --> 00:18:49.519 No one at the airline knew it existed. The maintenance 389 00:18:49.559 --> 00:18:52.799 crews didn't know, the flight instructors didn't know, and most tragically, 390 00:18:52.880 --> 00:18:54.839 Taptain Rasmussen had no idea. 391 00:18:55.039 --> 00:18:56.640 He was totally in the dark, totally. 392 00:18:57.039 --> 00:18:59.559 When his engines ingested the ice and began to surge, 393 00:18:59.599 --> 00:19:02.240 he did exactly what his lifetime of training taught him. 394 00:19:02.480 --> 00:19:05.519 He reduced power to save the engines, but the hidden 395 00:19:05.559 --> 00:19:09.400 lines of code in the computer simply registered low rpm 396 00:19:09.519 --> 00:19:10.200 during climb. 397 00:19:10.319 --> 00:19:12.960 It assumed he was throttling back for noise abatement. 398 00:19:13.440 --> 00:19:18.000 Exactly the ATR overrode his physical inputs, took control of 399 00:19:18.000 --> 00:19:21.599 the servos and pumped maximum fuel into the choking engines, 400 00:19:21.759 --> 00:19:25.799 ultimately causing those titanium fires and the total self destruction 401 00:19:25.880 --> 00:19:26.799