WEBVTT 1 00:00:00.120 --> 00:00:04.719 Picture the sky over southern California back in September of 2 00:00:04.799 --> 00:00:08.000 nineteen seventy eight. You're just looking up on this crisp, 3 00:00:08.240 --> 00:00:11.320 perfectly clear morning in San Diego. You know, the kind 4 00:00:11.320 --> 00:00:14.960 of sun drenched blue that just feels totally limitless. 5 00:00:15.000 --> 00:00:17.679 Oh yeah, those classics Southern California morning exactly. 6 00:00:17.879 --> 00:00:21.839 And gliding down through that pristine air is Pacific Southwest 7 00:00:21.879 --> 00:00:25.519 Airlines Flight one eighty two. It's this massive Boeing seven 8 00:00:25.679 --> 00:00:30.039 twenty seven, gracefully descending over the bustling city, and inside 9 00:00:30.079 --> 00:00:32.719 the cabin, I mean, the vibe is incredibly. 10 00:00:32.200 --> 00:00:34.600 Relaxed, right because a lot of them were actually airline staff, 11 00:00:34.640 --> 00:00:35.079 weren't they. 12 00:00:35.479 --> 00:00:37.439 Yeah. Out of the one hundred and twenty eight passengers 13 00:00:37.439 --> 00:00:40.119 on board, thirty of them are actually PSA employees just 14 00:00:40.200 --> 00:00:43.240 heading home after a shift. So the crew is joking around, 15 00:00:43.240 --> 00:00:45.359 people are looking out the windows at the neighborhoods below. 16 00:00:45.399 --> 00:00:48.520 It is the absolute picture of routine. But at exactly 17 00:00:48.640 --> 00:00:51.719 nine am, that calm is just violently. 18 00:00:51.280 --> 00:00:52.840 Shattered, completely shattered. 19 00:00:52.520 --> 00:00:54.960 And that patch of blue sky becomes the site of 20 00:00:55.000 --> 00:00:57.479 the worst aviation disaster in US history. 21 00:00:57.520 --> 00:00:59.560 At the time, it really was a morning that just 22 00:00:59.640 --> 00:01:02.479 fracked sure, the reality of everyone on the ground, you know, 23 00:01:03.039 --> 00:01:06.200 the aftermath of what happened in those few seconds. It 24 00:01:06.239 --> 00:01:09.480 didn't just leave a massive scar on San Diego. It 25 00:01:09.560 --> 00:01:13.239 actually forced a total ground up rewrite of how human 26 00:01:13.280 --> 00:01:14.480 beings navigate the sky. 27 00:01:14.719 --> 00:01:17.040 And that is exactly our mission for this deep dive. 28 00:01:17.159 --> 00:01:20.879 We are going to deconstruct this tragic mid air collision 29 00:01:20.920 --> 00:01:25.120 between a ninety one ton commercial jetliner and a tiny 30 00:01:25.159 --> 00:01:25.840 little cessna. 31 00:01:26.040 --> 00:01:28.719 It's just such an unbelievable mismatch in size. 32 00:01:28.319 --> 00:01:31.040 Right, and we're looking at this terrifying chain of entirely 33 00:01:31.159 --> 00:01:33.719 mundane events. I mean, we're talking about a single misheard 34 00:01:33.760 --> 00:01:37.560 syllable over a radio, a pilot adjusting a seat for comfort, 35 00:01:38.200 --> 00:01:41.439 and just a momentary distraction in the cockpit. We'll explore 36 00:01:41.480 --> 00:01:44.239 how those tiny human factors doomed one hundred and forty 37 00:01:44.280 --> 00:01:46.879 four people, and how investigators, you know, peace through the 38 00:01:46.959 --> 00:01:49.439 ashes to create the rigid rules that keep you safe 39 00:01:49.439 --> 00:01:51.079 on every single flight you take today. 40 00:01:51.200 --> 00:01:54.079 Yeah, to really grasp how this disaster materialized, you have 41 00:01:54.159 --> 00:01:57.480 to first picture the chaotic environment of San Diego's Lindbergh 42 00:01:57.519 --> 00:02:01.319 Field back in nineteen seventy eight. Because this wasn't your 43 00:02:01.480 --> 00:02:04.519 standard sprawling international airport out in the suburbs. 44 00:02:04.799 --> 00:02:06.359 It was right in the thick of it, wasn't it. Oh? 45 00:02:06.400 --> 00:02:08.919 Absolutely. It was the busiest single runway airport in North 46 00:02:08.919 --> 00:02:12.120 America and it was pretty notorious among pilots for its 47 00:02:12.240 --> 00:02:17.039 unforgiving geography. You had this very drastic terrain drop off 48 00:02:17.360 --> 00:02:20.599 just before the runway, and well, it was situated right 49 00:02:20.599 --> 00:02:21.840 in the heart of the city. 50 00:02:21.840 --> 00:02:24.840 Like flying right past skyscrapers. 51 00:02:24.080 --> 00:02:29.280 Exactly incredibly close to downtown high rises and dense residential neighborhoods. 52 00:02:29.439 --> 00:02:31.560 Man, it sounds like trying to land a commercial jet 53 00:02:31.639 --> 00:02:35.159 in a crowded football stadium. And you're not just dealing 54 00:02:35.199 --> 00:02:39.159 with the tricky geography, right, the airspace itself was just swarming. 55 00:02:39.360 --> 00:02:41.560 Swarming is the perfect word for it. You had heavy 56 00:02:41.560 --> 00:02:46.360 commercial jets, private student planes, military aircraft from nearby bases, 57 00:02:46.680 --> 00:02:50.560 all just funneling into this exact same small bowl of sky. 58 00:02:50.680 --> 00:02:53.199 The traffic volume was honestly staggering. 59 00:02:52.840 --> 00:02:54.120 Like how many flights are we talking? 60 00:02:54.439 --> 00:02:57.159 That confined space handled around six hundred flights a day. 61 00:02:57.360 --> 00:03:00.280 And the craziest part is air traffic control was operating 62 00:03:00.319 --> 00:03:04.800 under a system that seems well completely unthinkable now. It 63 00:03:04.840 --> 00:03:08.479 was essentially a first come, first serve shared airspace. 64 00:03:08.639 --> 00:03:12.280 Wait, first come, first serve. Imagine navigating a packed multi 65 00:03:12.360 --> 00:03:14.960 lane highway at two hundred miles per hour where you've 66 00:03:14.960 --> 00:03:19.400 got massive eighteen wheelers and tiny little sedans all weaving 67 00:03:19.439 --> 00:03:22.199 through the exact same lanes, but there are no lane 68 00:03:22.199 --> 00:03:25.240 markers and there are no stoplights. I mean, how was 69 00:03:25.280 --> 00:03:27.960 a system like that ever considered saved by anyone? 70 00:03:28.080 --> 00:03:30.039 I know it sounds insane to us now, but at 71 00:03:30.039 --> 00:03:33.759 the time, radar technology and ATC infrastructure, they just simply 72 00:03:33.800 --> 00:03:36.360 couldn't micro manage every single aircraft all the way to 73 00:03:36.400 --> 00:03:39.639 the ground. So the system relied heavily on the actual 74 00:03:39.759 --> 00:03:42.000 eyes of the pilots to maintain order. 75 00:03:42.240 --> 00:03:44.479 Just looking out the window and hoping for the best. 76 00:03:44.199 --> 00:03:47.319 Pretty much, and flying into this intense, high stakes environment 77 00:03:47.439 --> 00:03:50.439 is our cast of characters. So PSA Flight one eighty 78 00:03:50.439 --> 00:03:53.000 two was commanded by Captain Jim McFerrin, who was this 79 00:03:53.159 --> 00:03:54.960 highly regarded seventeen year veteran. 80 00:03:55.080 --> 00:03:57.400 Yeah, he was known to his peers as a born pilot. 81 00:03:57.159 --> 00:04:00.479 Right, exactly real natural and he was flying alongside First 82 00:04:00.520 --> 00:04:01.479 Officer Bob. 83 00:04:01.240 --> 00:04:04.039 Fox, and PSA had this really unique corporate culture back 84 00:04:04.080 --> 00:04:06.759 then too, I mean their official motto was literally catch 85 00:04:06.800 --> 00:04:09.719 our smile, and they actually painted huge smiles on the 86 00:04:09.759 --> 00:04:10.680 noses of their planes. 87 00:04:10.960 --> 00:04:13.479 Yeah, the crews were known for being incredibly professional, but 88 00:04:13.520 --> 00:04:17.639 also highly personable and just laid back. They wanted the 89 00:04:17.680 --> 00:04:21.480 flying experience to be fun and stress free for everyone. Right. 90 00:04:21.759 --> 00:04:25.079 But meanwhile, flying right below that descending seven twenty seven, 91 00:04:25.120 --> 00:04:28.120 sharing that exact same patch of sky, is a tiny 92 00:04:28.120 --> 00:04:31.639 Cessna one seventy two. It belonged to a local flight training. 93 00:04:31.319 --> 00:04:35.160 School, and inside that Sessna are an instructor and a 94 00:04:35.199 --> 00:04:38.079 student pilot just out on a routine training flight. 95 00:04:38.240 --> 00:04:41.279 Okay, so let's track the chronological timeline here, because the 96 00:04:41.279 --> 00:04:44.680 way this nightmare unfolds is just chilling. The approach controller 97 00:04:44.759 --> 00:04:47.160 on the ground spots the tiny Cessna on his radar, 98 00:04:47.519 --> 00:04:50.560 sees it's ahead of the descending jet, and he radios 99 00:04:50.560 --> 00:04:52.199 the PSA crew to warn them. 100 00:04:52.120 --> 00:04:53.279 Right, standard procedure. 101 00:04:53.399 --> 00:04:55.639 So the jet crew looks out the window, they spot 102 00:04:55.680 --> 00:04:58.480 the Cessna and they reply, got it, traffic in sight. 103 00:04:58.600 --> 00:05:01.040 And once they say that, the controller tells them to 104 00:05:01.120 --> 00:05:02.639 maintain visual separation. 105 00:05:02.959 --> 00:05:06.279 And that phrase right there, visual separation is the entire 106 00:05:06.439 --> 00:05:07.879 folkrum of this tragedy. 107 00:05:07.879 --> 00:05:10.519 Because it shifts the blame, right or the responsibility. I 108 00:05:10.519 --> 00:05:11.920 should say, yes, exactly. 109 00:05:12.279 --> 00:05:15.040 In the Aviation Protocols of nineteen seventy eight, the moment 110 00:05:15.079 --> 00:05:18.439 a jet pilot acknowledges they have visual contact with another plane, 111 00:05:18.839 --> 00:05:22.399 the legal and practical responsibility to avoid a collision shifts entirely. 112 00:05:23.000 --> 00:05:25.160 It goes from the air traffic controller looking at a 113 00:05:25.160 --> 00:05:28.519 safe radar screen directly to the pilot looking out the windshield. 114 00:05:28.600 --> 00:05:30.279 So they're on their own pretty much. 115 00:05:30.519 --> 00:05:33.480 It's basically a maritime rule applied to the sky. The 116 00:05:33.480 --> 00:05:37.079 faster overtaking vessel is solely responsible for steering clear of 117 00:05:37.120 --> 00:05:38.439 the slower one wow. 118 00:05:38.639 --> 00:05:41.199 So the controller on the ground just steps back. The 119 00:05:41.240 --> 00:05:44.959 PSA crew is now one hundred percent responsible for avoiding 120 00:05:44.959 --> 00:05:47.439 the Sessna. They know it's there, they explicitly confirmed they 121 00:05:47.439 --> 00:05:51.120 saw it. But at exactly nine am, this ninety one 122 00:05:51.199 --> 00:05:54.000 ton Boeing flying at almost three hundred kilometers per hour 123 00:05:54.360 --> 00:05:56.519 just runs down the tiny sessa from right behind. 124 00:05:56.639 --> 00:06:00.600 Yeah, the destruction was just instantaneous. The sheer energy of 125 00:06:00.639 --> 00:06:03.560 a Boeing seven twenty seven impacting a light aircraft midair. 126 00:06:03.680 --> 00:06:06.079 I mean it tore the cessant apart instantly. 127 00:06:05.920 --> 00:06:08.560 And thousands of people on the ground in San Diego 128 00:06:08.680 --> 00:06:12.439 just watched this happen above their heads. A massive mushroom 129 00:06:12.519 --> 00:06:15.519 cloud of smoke and fire or erupts in the morning sky. 130 00:06:16.319 --> 00:06:21.519 Pieces of the fuselage, passenger seats, and horrifyingly bodies rained 131 00:06:21.560 --> 00:06:24.800 down into this quiet residential neighborhood called North Park. 132 00:06:25.199 --> 00:06:27.480 It's just unfathomable for the people living there. 133 00:06:27.600 --> 00:06:31.279 The devastation on the ground was absolutely apocalyptic. Twenty two 134 00:06:31.319 --> 00:06:33.959 homes were completely destroyed by the falling wreckage. 135 00:06:34.279 --> 00:06:37.199 One hundred and forty four people died, and that toll 136 00:06:37.319 --> 00:06:41.480 included everyone on both of the aircraft, plus seven residents 137 00:06:41.519 --> 00:06:44.000 on the ground who were literally just going about their 138 00:06:44.040 --> 00:06:46.879 morning routines, drinking coffee, getting ready for work. 139 00:06:47.120 --> 00:06:50.040 Just awful. And when the National Transportation Safety Board the 140 00:06:50.120 --> 00:06:54.199 NTSB dispatched their lead investigator, Wally Funk, from Los Angeles, 141 00:06:54.480 --> 00:06:57.360 the scenes she arrived at basically resembled a war zone. 142 00:06:57.720 --> 00:07:01.120 It was a massive, horrific puzzle skadded across the city. 143 00:07:01.240 --> 00:07:03.360 The bulk of the jet came down at the intersection 144 00:07:03.399 --> 00:07:06.639 of Dwight and Nile Streets, leaving a huge crater, while 145 00:07:06.680 --> 00:07:09.199 the mangled remains of the cessena were actually found about 146 00:07:09.240 --> 00:07:10.120 six blocks away. 147 00:07:10.399 --> 00:07:13.720 And what's crazy is that the local media narrative formed 148 00:07:13.759 --> 00:07:17.399 before the fires were even put out. Everyone immediately blamed 149 00:07:17.439 --> 00:07:18.839 the student pilot in the Cessna. 150 00:07:19.079 --> 00:07:23.560 Of course they did. People naturally assume the massive commercial 151 00:07:23.560 --> 00:07:27.120 airliner on an assigned glide path has the right of way, 152 00:07:27.519 --> 00:07:30.560 and well, the amateur in the little plane must have 153 00:07:30.560 --> 00:07:33.160 done something incredibly reckless to get in their way. 154 00:07:33.120 --> 00:07:37.480 Right, But investigators don't deal in assumptions. They deal in data. 155 00:07:38.079 --> 00:07:40.759 When they pulled the secondary surveillance radar tracks from a 156 00:07:40.800 --> 00:07:44.639 station in Los Angeles and calculated the exact trajectories of 157 00:07:44.680 --> 00:07:48.319 the two planes, the math told a completely different story. 158 00:07:48.120 --> 00:07:49.319 A completely reverse story. 159 00:07:49.360 --> 00:07:52.399 Honestly, the Cessna didn't veer wildly into the jet. The 160 00:07:52.439 --> 00:07:54.879 seven to twenty seven ran straight through the back of 161 00:07:54.879 --> 00:07:55.720 the Cessna. 162 00:07:55.519 --> 00:07:59.000 Which opens up this truly terrifying mystery for the NTSB 163 00:08:00.040 --> 00:08:02.120 on Earth does a veteran jet crew run down an 164 00:08:02.160 --> 00:08:05.000 airplane they already explicitly confirmed they saw right. 165 00:08:05.079 --> 00:08:07.600 It makes no sense. So what was the first clue. 166 00:08:07.720 --> 00:08:09.680 Well, the first piece of that puzzle was actually found 167 00:08:09.759 --> 00:08:13.399 inside the tiny Cessna. Because it was a training flight. 168 00:08:13.839 --> 00:08:17.480 The student pilot was practicing flying strictly by instruments, and 169 00:08:17.560 --> 00:08:20.439 to do that, the student was wearing a specific device 170 00:08:20.519 --> 00:08:22.079 called a training hood. 171 00:08:22.560 --> 00:08:24.759 A training hood is that kind of like putting blinders 172 00:08:24.759 --> 00:08:26.519 on a horse, so they only look straight ahead. 173 00:08:26.680 --> 00:08:30.439 It's very similar in design, yeah, but the physiological effect 174 00:08:30.439 --> 00:08:33.600 on a human pilot is much more profound. It's basically 175 00:08:33.679 --> 00:08:37.120 a physical shield that extends out from the forehead and 176 00:08:37.240 --> 00:08:41.000 completely blocks out the side windows and the natural horizon. 177 00:08:40.720 --> 00:08:42.399 So they can't see the sky at all. 178 00:08:42.639 --> 00:08:45.879 Exactly. The pilot can only see the glowing dials on 179 00:08:45.919 --> 00:08:48.720 the instrument panel in front of them. But the problem 180 00:08:48.840 --> 00:08:52.000 is humans rely heavily on the visual horizon to maintain 181 00:08:52.039 --> 00:08:54.879 our sense of balance. Without it, the fluid in your 182 00:08:54.919 --> 00:08:57.639 inner ear can play some really dangerous tricks on your brain. 183 00:08:57.799 --> 00:08:59.679 Oh, like spatial disorientation. 184 00:09:00.039 --> 00:09:03.159 Exactly. A pilot can feel like they're flying perfectly straight 185 00:09:03.200 --> 00:09:06.399 and level while the aircraft is actually entering a slow 186 00:09:06.519 --> 00:09:07.279 banking turn. 187 00:09:07.559 --> 00:09:10.960 Okay, so the student pilot got disoriented because of the hood, 188 00:09:11.399 --> 00:09:14.480 and the radar data confirms this. Right. The Cessna was 189 00:09:14.480 --> 00:09:18.039 assigned to hold a strict seventy degree heading, but they 190 00:09:18.120 --> 00:09:22.039 drifted slightly off course, essentially turning right into the direct 191 00:09:22.039 --> 00:09:23.799 flight path of the descending bowing. 192 00:09:24.159 --> 00:09:28.799 The drift definitely happened. However, when the NTSB plotted those 193 00:09:28.879 --> 00:09:31.960 radar tracks and meticulously calculated the viewing angles from the 194 00:09:31.960 --> 00:09:35.320 seven to twenty sevens cockpit, they made a really stunning discovery, 195 00:09:35.399 --> 00:09:38.679 which was, even with the cessna's drift, the small plane 196 00:09:38.720 --> 00:09:41.679 was technically visible through the jets windshield for one hundred 197 00:09:41.679 --> 00:09:43.519 and seventy seconds leading up to the impact. 198 00:09:43.600 --> 00:09:46.240 Hey, one hundred and seventy seconds. That's almost three full 199 00:09:46.360 --> 00:09:50.000 minutes of clear visibility in an aircraft traveling at three 200 00:09:50.039 --> 00:09:53.559 hundred kilometers per hour. Three minutes is an absolute eternity. 201 00:09:53.600 --> 00:09:55.840 I mean, you can cover miles of sky in that time, 202 00:09:55.919 --> 00:09:56.559 you really can. 203 00:09:57.080 --> 00:09:59.519 So investigators had to figure out how something sitting in 204 00:09:59.559 --> 00:10:04.240 planes just becomes completely invisible to train professionals, and they 205 00:10:04.320 --> 00:10:07.879 uncovered this series of visual illusions that essentially deleted the 206 00:10:07.919 --> 00:10:09.840 Cessna from the pilot's perception entirely. 207 00:10:10.080 --> 00:10:11.840 That's terrifying. What was the first illusion? 208 00:10:12.120 --> 00:10:15.200 The first one is basically a biological quirk of the 209 00:10:15.240 --> 00:10:17.360 human eye regarding relative motion. 210 00:10:18.000 --> 00:10:20.600 Okay, so because both planes are flying in the same 211 00:10:20.679 --> 00:10:23.799 general direction and at roughly the same altitude at that 212 00:10:23.840 --> 00:10:28.759 specific moment, the cessna isn't actually moving across the jets windshield. Right, 213 00:10:28.840 --> 00:10:31.200 It isn't crossing from left to right or dropping from 214 00:10:31.200 --> 00:10:31.879 top to bottom. 215 00:10:32.000 --> 00:10:36.240 Exactly. Evolution wired are favile vision. You know, the sharp 216 00:10:36.519 --> 00:10:40.159 central part of our eyesight to detect motion. It's how 217 00:10:40.159 --> 00:10:42.879 our ancestors spotted predators hiding in the brush. 218 00:10:43.080 --> 00:10:45.159 Right. If it moves, you see it. If it stays still, 219 00:10:45.200 --> 00:10:45.799 it blends in. 220 00:10:46.039 --> 00:10:49.440 Exactly, when an object is completely static in your field 221 00:10:49.480 --> 00:10:52.360 of vision, it just slowly grows slightly larger as you 222 00:10:52.399 --> 00:10:56.720 approach it. The human brain naturally filters out static objects as. 223 00:10:56.679 --> 00:10:59.960 Background noise, so it literally becomes a blind spot generated 224 00:11:00.039 --> 00:11:02.840 by our own biology. But even if it's static, you'd 225 00:11:02.840 --> 00:11:05.120 think a plane against the open sky would stand out. 226 00:11:05.240 --> 00:11:07.919 You would think so, except they weren't looking at the 227 00:11:07.960 --> 00:11:08.720 open sky. 228 00:11:08.639 --> 00:11:10.360 Oh, right, because they were descending. 229 00:11:10.679 --> 00:11:13.559 Yes, the jet was in a descent, so the pilots 230 00:11:13.600 --> 00:11:16.559 were looking down over the sprawling urban grid of San Diego, 231 00:11:17.200 --> 00:11:20.519 and the cessna was flying low set against this chaotic, 232 00:11:20.639 --> 00:11:25.480 high contrast backdrop of white roofs, dark roofs, paved asphalt roads, 233 00:11:25.759 --> 00:11:26.639 and green trees. 234 00:11:26.960 --> 00:11:29.960 So the painted surface of the tiny cessna just perfectly 235 00:11:29.960 --> 00:11:32.639 blended into the visual clutter of the city below them. 236 00:11:32.720 --> 00:11:34.159 It was perfect camouflage. 237 00:11:34.200 --> 00:11:36.960 That is wild. It's like trying to spot a specific 238 00:11:37.080 --> 00:11:41.080 piece of gray confetti falling against a massive mosaic tile floor. 239 00:11:41.320 --> 00:11:43.960 You'd never see it unless it moved across the tiles. 240 00:11:44.039 --> 00:11:46.039 That's a great way to put it. But then you 241 00:11:46.120 --> 00:11:48.960 have to add a third, incredibly bizarre element into this 242 00:11:49.039 --> 00:11:51.480 psychological trap, the phantom plane. 243 00:11:51.639 --> 00:11:53.480 The phantom plane. Okay, tell me about this. 244 00:11:53.600 --> 00:11:56.120 When investigators listened to the cockpit voice recorder tape, they 245 00:11:56.120 --> 00:11:58.840 heard the captain say, about thirty five seconds before the crash, 246 00:11:59.000 --> 00:12:01.679 I saw him about one point zero probably behind us now. 247 00:12:01.919 --> 00:12:04.519 And then shortly after he spots another plane flying the 248 00:12:04.559 --> 00:12:06.519 opposite way and says, there's one underneath. 249 00:12:06.679 --> 00:12:10.480 But wait, the NTSB plotted the radar right and the 250 00:12:10.480 --> 00:12:13.159 Cessna was never at their one point zero position. It 251 00:12:13.240 --> 00:12:16.120 was always out their front left window, near their eleven 252 00:12:16.120 --> 00:12:19.559 point zero zero position. So what plane was the captain 253 00:12:19.559 --> 00:12:20.360 actually looking at? 254 00:12:20.519 --> 00:12:23.320 That was the big question. So investigators canvassed in the 255 00:12:23.399 --> 00:12:26.919 neighborhoods and collected over two hundred witness reports from people 256 00:12:26.919 --> 00:12:30.919 on the ground and sixteen of those witnesses reported seeing 257 00:12:31.000 --> 00:12:36.480 other completely unidentified aircraft in the immediate area at that exact. 258 00:12:36.120 --> 00:12:38.879 Time, because back in nineteen seventy eight, a lot of 259 00:12:38.919 --> 00:12:42.639 small private planes didn't even carry transponders, so they wouldn't 260 00:12:42.679 --> 00:12:44.919 ping the air traffic control radar at all. They were 261 00:12:44.960 --> 00:12:47.039 essentially ghosts to the system exactly. 262 00:12:47.360 --> 00:12:51.399 So the crew likely spotted a completely different untranspondered plane, 263 00:12:51.639 --> 00:12:53.720 assumed it was the sessena of the controller had warned 264 00:12:53.720 --> 00:12:56.399 them about, mentally checked it off there to do list, 265 00:12:56.879 --> 00:12:58.399 and just thought the sky ahead was clear. 266 00:12:58.639 --> 00:13:02.200 Man, it's just this tragical alignment of visual and mental illusions. 267 00:13:02.559 --> 00:13:05.720 But the NTSB wasn't satisfied with just that, were they No. 268 00:13:05.919 --> 00:13:08.639 They weren't. They went further into those one hundred and 269 00:13:08.639 --> 00:13:12.159 seventy seconds of visibility by setting up an actual physical 270 00:13:12.200 --> 00:13:15.639 recreation in a hangar, and that led to a massive 271 00:13:15.639 --> 00:13:19.639 discovery about the physical mechanics of the cockpit itself, right. 272 00:13:19.600 --> 00:13:23.759 Because aircraft manufacturers design cockpits with something called a design 273 00:13:23.879 --> 00:13:24.960 eye reference point. 274 00:13:25.039 --> 00:13:26.600 Yeah, it's a very specific setup. 275 00:13:26.639 --> 00:13:29.399 It's this system of little balls mounted on the center 276 00:13:29.440 --> 00:13:32.039 post of the windshield, and a pilot is supposed to 277 00:13:32.440 --> 00:13:35.960 raise or lower their seat until their vision perfectly aligns 278 00:13:35.960 --> 00:13:38.759 with those balls. It ensures their eyes are in the 279 00:13:38.799 --> 00:13:42.759 optimal viewing position, providing the exact site lines the engineers 280 00:13:42.799 --> 00:13:43.840 originally intended. 281 00:13:44.120 --> 00:13:46.600 The issue, though, is that using this reference point wasn't 282 00:13:46.639 --> 00:13:50.120 strictly enforced at all. Pilots obviously come in all different 283 00:13:50.159 --> 00:13:52.440 heights and builds, and once they're up in the air, 284 00:13:52.919 --> 00:13:55.000 many pilots will just adjust the seats down. 285 00:13:55.080 --> 00:13:56.399 Why just for comfort? 286 00:13:56.759 --> 00:13:59.159 Yeah, sitting lower is often a lot more comfortable for 287 00:13:59.200 --> 00:14:01.399 their lower backs, and it actually gives them a much 288 00:14:01.440 --> 00:14:04.759 better straight on view of the complex instrument panels rate 289 00:14:04.840 --> 00:14:05.759 inside the cockpit. 290 00:14:05.960 --> 00:14:09.240 I mean, it's basically the aviation equivalent of adjusting your 291 00:14:09.279 --> 00:14:11.919 car seats so far back and low to get comfortable 292 00:14:11.960 --> 00:14:15.120 on a long road trip that you unknowingly create this 293 00:14:15.320 --> 00:14:18.440 massive blind spot right over your own hood. Except you know, 294 00:14:18.519 --> 00:14:21.159 on a Boeing seven twenty seven, the hood is the 295 00:14:21.200 --> 00:14:23.559 long nose of a ninety one ton jetliner. 296 00:14:24.000 --> 00:14:28.360 Exactly. So, the NTSB investigators placed panoramic cameras in the 297 00:14:28.360 --> 00:14:31.120 cockpit of a seven to twenty seven inside a hangar, 298 00:14:31.679 --> 00:14:34.960 and they lowered the captain's seat to a typical comfortable 299 00:14:35.000 --> 00:14:37.879 setting just a few inches down and what happened. The 300 00:14:37.919 --> 00:14:40.879 results were devastating. Those one hundred and seventy seconds of 301 00:14:40.879 --> 00:14:44.639 clear visibility we talked about they instantly vanished. Oh my god, 302 00:14:44.799 --> 00:14:47.960 it shranked down to just five to ten seconds because 303 00:14:47.960 --> 00:14:50.399 a seven twenty seven flies with a slightly nose up 304 00:14:50.440 --> 00:14:53.120 pitch during its descent. Dropping the seat just a few 305 00:14:53.159 --> 00:14:55.799 inches meant the tiny Sessena was entirely obscured by the 306 00:14:55.799 --> 00:14:58.080 nose of the jet for almost the entire approach. 307 00:14:58.279 --> 00:15:00.279 So by the time the Sessina was close enough to 308 00:15:00.279 --> 00:15:02.679 actually see, the pilots would have had to physically unbuckle 309 00:15:02.720 --> 00:15:05.440 their seat belts and lean way forward over the steering 310 00:15:05.519 --> 00:15:06.600 yoke just to spot it. 311 00:15:06.639 --> 00:15:09.399 They were fundamentally blind to the hazard directly in front 312 00:15:09.399 --> 00:15:09.720 of them. 313 00:15:09.840 --> 00:15:13.000 But wait, if the pilots couldn't physically see the Sessna, 314 00:15:13.480 --> 00:15:16.480 why didn't the air traffic controllers on the ground intervene. 315 00:15:16.799 --> 00:15:18.720 I mean they had the radar screens. They were supposed 316 00:15:18.720 --> 00:15:20.000 to be the ultimate safety net. 317 00:15:20.039 --> 00:15:23.000 Well, this introduced is a concept that still plagues complex 318 00:15:23.120 --> 00:15:26.399 systems to this day, and that is alarm fatigue. 319 00:15:26.559 --> 00:15:29.360 Alarm fatigue. Okay, how did that play into this. 320 00:15:29.799 --> 00:15:32.759 The approach control facility, which was the one handling the 321 00:15:32.759 --> 00:15:36.080 broader regional airspace before planes were handed off to the 322 00:15:36.080 --> 00:15:39.960 local airport tower, they had recently installed a brand new, 323 00:15:40.440 --> 00:15:43.480 state of the art collision alert system and did it work. 324 00:15:43.799 --> 00:15:47.159 It actually worked perfectly. That morning, the computer calculated the 325 00:15:47.200 --> 00:15:49.720 closure rate between the seven twenty seven and the Sessna, 326 00:15:50.159 --> 00:15:52.399 and a loud alarm went off in the control room, 327 00:15:52.639 --> 00:15:53.840 warning of an imminent strike. 328 00:15:53.919 --> 00:15:56.919 Wait, really, how does an air traffic controller just ignore 329 00:15:57.000 --> 00:15:58.399 a blaring collision alarm? 330 00:15:58.679 --> 00:16:01.759 Because that specific system was so highly sensitive, it was 331 00:16:01.799 --> 00:16:05.039 generating an average of thirteen false alarms every single day. 332 00:16:05.399 --> 00:16:08.440 Wow, it's the car alarm effect. Like when you live 333 00:16:08.440 --> 00:16:10.240 in a busy city and you hear a car alarm 334 00:16:10.279 --> 00:16:12.120 going off down the street. You don't jump up and 335 00:16:12.120 --> 00:16:14.799 call the police. You just assume it's malfunctioning or someone 336 00:16:14.840 --> 00:16:17.120 bump the bumper. You completely tune it out. 337 00:16:17.240 --> 00:16:20.159 Exactly. The approach controller did actually notice the alert, and 338 00:16:20.240 --> 00:16:22.559 he even mentioned it to a supervisor. Yeah, but because 339 00:16:22.600 --> 00:16:26.039 the system cried wolf so often, and because the PSA 340 00:16:26.200 --> 00:16:29.519 crew had previously confirmed they had the sessinin sight, the 341 00:16:29.559 --> 00:16:31.679 controllers just disregarded the computer. 342 00:16:31.840 --> 00:16:33.360 They figured the pilots had it covered. 343 00:16:33.440 --> 00:16:36.720 Yeah, they assumed the pilots were handling it under visual 344 00:16:36.759 --> 00:16:37.320 flight rules. 345 00:16:37.399 --> 00:16:40.759 So the approach center hands the jet off to the 346 00:16:40.879 --> 00:16:45.840 Lindberg local tower controller for the final landing approach, and 347 00:16:45.879 --> 00:16:49.919 this leads us right into the final excruciating seventy seconds 348 00:16:49.919 --> 00:16:53.320 of the flight. The cockpit voice recorder reveals a highly 349 00:16:53.320 --> 00:16:57.519 distracted crew at this point. They are chatting casually, adjusting flaps, 350 00:16:57.600 --> 00:17:00.639 lowering the landing gear. The workload in the hawkpit is 351 00:17:00.799 --> 00:17:01.519 really high. 352 00:17:01.559 --> 00:17:02.960 It's a very busy phase of flight. 353 00:17:03.080 --> 00:17:06.480 But the captain, seemingly unsure of where the Sessna actually 354 00:17:06.519 --> 00:17:09.400 is at this moment, gets on the radio with the 355 00:17:09.440 --> 00:17:11.440 tower controller to check in, and. 356 00:17:11.440 --> 00:17:15.839 The transcript of this specific exchange is just haunting. The 357 00:17:15.839 --> 00:17:18.759 PSA captain keys the microphone and says, I think he's 358 00:17:18.759 --> 00:17:19.799 passed off to our right. 359 00:17:19.960 --> 00:17:25.279 He uses the word past passed past tense, meaning Sessna's 360 00:17:25.319 --> 00:17:28.240 behind us. Our interaction is completely over right. 361 00:17:28.680 --> 00:17:31.400 But when the investigators listened to the corresponding recording from 362 00:17:31.440 --> 00:17:34.200 the control tower on the ground, they found something awful. 363 00:17:34.799 --> 00:17:38.160 A burst of routine radio static hits the frequency at 364 00:17:38.160 --> 00:17:41.000 the exact millisecond, the captain speaks, oh no, So what 365 00:17:41.039 --> 00:17:44.559 the tower controller actually heard in his headset was I 366 00:17:44.599 --> 00:17:45.839 think he's passing off. 367 00:17:45.640 --> 00:17:50.920 To our right, passing pasig present tense. A single syllable 368 00:17:51.000 --> 00:17:54.359 altered by static changes the entire meaning of the transmission, 369 00:17:55.119 --> 00:17:58.160 because if the controller hears pass past tense and looks 370 00:17:58.200 --> 00:18:00.680 at his radar screen and sees the two planes are merging, 371 00:18:01.000 --> 00:18:03.039 he knows instantly the pilot has lost sight of the 372 00:18:03.079 --> 00:18:06.839 target right and he would order an immediate evasive turn exactly. 373 00:18:07.160 --> 00:18:09.839 But by hearing the word passing, the controller interprets the 374 00:18:09.880 --> 00:18:12.200 transmission as just a routine status update. 375 00:18:12.200 --> 00:18:15.599 Because it implies the pilot still has active visual eyes 376 00:18:15.640 --> 00:18:19.119 on the Cessna and is deliberately managing the physical gap 377 00:18:19.160 --> 00:18:19.720 between them. 378 00:18:19.880 --> 00:18:21.839 Right. It sounded to the ground like the crew was 379 00:18:21.880 --> 00:18:23.480 in total control of the situation. 380 00:18:23.920 --> 00:18:27.160 So because of that one misheard syllable, the controller assumed 381 00:18:27.200 --> 00:18:30.240 everything was fine and just stayed silent, and moments later 382 00:18:30.359 --> 00:18:31.440 the planes collided. 383 00:18:31.640 --> 00:18:35.079 It's just brutal. When the NTSB released their final report 384 00:18:35.119 --> 00:18:38.279 in the spring of nineteen seventy nine, they obviously had 385 00:18:38.279 --> 00:18:41.240 to assign fault for the tragedy, and the primary cause 386 00:18:41.319 --> 00:18:43.880 was placed squarely on the shoulders of the PSA crew. 387 00:18:44.119 --> 00:18:47.039 I mean legally, that makes sense because they accepted visual 388 00:18:47.079 --> 00:18:49.720 separation early on. Once they said they had the traffic 389 00:18:49.720 --> 00:18:52.839 in sight, they took full legal ownership of avoiding it. 390 00:18:52.960 --> 00:18:57.119 Yeah, their critical failure was not explicitly and urgently telling 391 00:18:57.160 --> 00:19:00.000 air traffic Control the very second they lost visual cass 392 00:19:00.039 --> 00:19:02.880 contact with the Cessna instead of just asking for help, 393 00:19:03.160 --> 00:19:04.359 they assumed they had passed it. 394 00:19:04.680 --> 00:19:08.240 But the NTSB report distributed the blame across the whole system, too, 395 00:19:08.319 --> 00:19:08.799 didn't it. 396 00:19:09.160 --> 00:19:13.160 They did. The Cessna pilot contributed by failing to maintain 397 00:19:13.240 --> 00:19:16.599 his assigned heading while under the hood. Air traffic control 398 00:19:16.640 --> 00:19:20.599 contributed by failing to provide specific radar vectors to keep 399 00:19:20.599 --> 00:19:23.680 the aircraft physically separated, and of course, for allowing alarm 400 00:19:23.680 --> 00:19:26.519 fatigue to override a legitimate computer warning. 401 00:19:26.680 --> 00:19:30.599