1 00:00:00,000 --> 00:00:04,162 WWW.MY-SUBS.CO 1 00:00:01,040 --> 00:00:02,960 NARRATOR: Staring down a thunderstorm 2 00:00:03,000 --> 00:00:04,200 above the North Sea... 3 00:00:04,800 --> 00:00:06,080 Take a look at that. 4 00:00:06,120 --> 00:00:07,520 MAN: Oh, I don't like it. 5 00:00:07,560 --> 00:00:11,000 ..a modern turboprop is struck by more than a million volts. 6 00:00:11,920 --> 00:00:12,920 Oh! 7 00:00:13,720 --> 00:00:14,960 After the lightning strike, 8 00:00:15,000 --> 00:00:17,880 you're obviously looking to see, "Have we been damaged?" 9 00:00:17,920 --> 00:00:19,400 Damn it! The plane's not responding. 10 00:00:19,440 --> 00:00:20,760 Help me pull. 11 00:00:20,800 --> 00:00:22,640 You can fly an aircraft without a compass. 12 00:00:22,680 --> 00:00:24,280 You can fly an aircraft without a radio. 13 00:00:24,320 --> 00:00:26,120 Mayday, Mayday, we've been struck by lightning 14 00:00:26,160 --> 00:00:27,760 and are having control difficulties. 15 00:00:27,800 --> 00:00:31,040 But you can't fly an aircraft without functioning controls. 16 00:00:31,080 --> 00:00:32,880 But investigators can't figure out 17 00:00:32,920 --> 00:00:36,560 how lightning could have caused the plane to behave the way it did. 18 00:00:36,600 --> 00:00:37,600 Look at that. 19 00:00:37,640 --> 00:00:40,240 I mean, the elevators are trying to get the nose to pitch down 20 00:00:40,280 --> 00:00:41,400 instead of up. 21 00:00:41,440 --> 00:00:44,760 We'd not come across an aircraft where there would be this difference 22 00:00:44,800 --> 00:00:46,040 between the pilot input 23 00:00:46,080 --> 00:00:48,160 and what the aircraft was actually doing. 24 00:00:48,200 --> 00:00:49,720 MAN: Oh, no! 25 00:00:49,760 --> 00:00:50,840 We're dropping! 26 00:00:51,680 --> 00:00:53,360 They were so distracted by that, 27 00:00:53,400 --> 00:00:56,560 they failed to see what was really going on. 28 00:00:59,160 --> 00:01:00,320 MAN: (SHOUTING) Mayday, Mayday! 29 00:01:03,520 --> 00:01:08,039 (RADIO CHATTER) 30 00:01:23,840 --> 00:01:26,120 It's 6:45 pm. 31 00:01:27,400 --> 00:01:32,120 Loganair flight 6780 cruises over the North Sea near Scotland. 32 00:01:35,840 --> 00:01:39,240 Let's get lower. Request flight level 1-1-0 please. 33 00:01:39,960 --> 00:01:42,080 Approach, Loganair 67-80, 34 00:01:42,120 --> 00:01:44,360 requesting descent to 1-1-0. 35 00:01:44,400 --> 00:01:47,720 MAN: (VIA RADIO) 67-80, descend to 1-1-0. 36 00:01:48,760 --> 00:01:52,760 The plane is more than halfway through a 65-minute flight. 37 00:01:56,240 --> 00:01:59,400 Most of the passengers live on the Shetland Islands. 38 00:01:59,440 --> 00:02:01,040 - All done? - Yes, thank you. 39 00:02:01,080 --> 00:02:02,280 I'll take that. 40 00:02:02,320 --> 00:02:06,160 Many are returning home from holiday shopping in Aberdeen. 41 00:02:06,200 --> 00:02:09,320 Air travel is massively important, to residents in Shetland. 42 00:02:12,040 --> 00:02:14,120 It's important for work meetings. 43 00:02:14,160 --> 00:02:17,160 It's important for sporting events, for holidays. 44 00:02:17,200 --> 00:02:19,560 It's the fastest way to travel off-island, 45 00:02:19,600 --> 00:02:21,040 so it's quick and convenient. 46 00:02:23,720 --> 00:02:25,440 The Captain is experienced. 47 00:02:25,480 --> 00:02:30,960 He has more than 5,000 flying hours and is the pilot flying tonight. 48 00:02:32,440 --> 00:02:34,360 Passing flight level 1-5-0. 49 00:02:34,400 --> 00:02:36,720 The First Officer is monitoring the instruments 50 00:02:36,760 --> 00:02:39,280 and handling all communications. 51 00:02:39,320 --> 00:02:41,360 Approach, Logan 67-80. 52 00:02:41,400 --> 00:02:43,440 Descending through flight level 1-5-0, 53 00:02:43,480 --> 00:02:45,560 for the I-L-S, runway 2-7. 54 00:02:46,920 --> 00:02:49,480 She has more than 1,000 flying hours. 55 00:02:50,560 --> 00:02:53,040 The crew had good total experience. 56 00:02:53,080 --> 00:02:56,520 Of course, they didn't have a lot of experience flying the Saab 2,000, 57 00:02:56,560 --> 00:02:59,760 but still it was a normal experienced crew. 58 00:03:02,000 --> 00:03:06,160 The Saab 2,000 is a twin-engine high-speed turboprop. 59 00:03:06,200 --> 00:03:09,120 It's a plane that aviation analyst Hans-Peter Graf 60 00:03:09,160 --> 00:03:10,800 knows extremely well. 61 00:03:10,840 --> 00:03:16,120 The Saab 2,000 is the most advanced turboprop still existing and flying. 62 00:03:18,120 --> 00:03:22,520 It has a jet-like performance paired with low fuel consumption. 63 00:03:24,000 --> 00:03:25,720 And it had real good performance 64 00:03:25,760 --> 00:03:29,120 to fly in and out of mountainous terrain. 65 00:03:30,000 --> 00:03:31,080 They're travelling north 66 00:03:31,120 --> 00:03:32,640 from Aberdeen, Scotland, 67 00:03:32,680 --> 00:03:35,000 to Sumburgh on the Shetland Islands, 68 00:03:35,040 --> 00:03:36,480 a remote archipelago 69 00:03:36,520 --> 00:03:39,640 prone to winter squalls and even hurricanes. 70 00:03:44,640 --> 00:03:46,680 MAN: (VIA RADIO) Logan Air 67-80, 71 00:03:46,720 --> 00:03:47,720 for your information, 72 00:03:47,760 --> 00:03:50,000 looks like the ATIS antenna at Sumburgh 73 00:03:50,040 --> 00:03:51,200 has been struck by lightning, 74 00:03:51,240 --> 00:03:53,040 so the system's not functioning. 75 00:03:53,080 --> 00:03:55,240 I'll update conditions when I get them. 76 00:03:55,280 --> 00:03:56,760 FEMALE PILOT: OK, thanks for the update. 77 00:03:57,640 --> 00:03:58,640 There's been a lot of that 78 00:03:58,680 --> 00:03:59,680 so far this winter. 79 00:04:01,360 --> 00:04:04,960 The ATIS, or Automatic Terminal Information Service, 80 00:04:05,000 --> 00:04:09,000 provides pilots with continuous broadcast of essential information. 81 00:04:11,160 --> 00:04:14,000 It broadcasts weather and airport information 82 00:04:14,040 --> 00:04:15,680 every 30 minutes, 83 00:04:15,720 --> 00:04:20,440 on which the pilots will base their approaches and landings. 84 00:04:21,400 --> 00:04:22,960 Why don't you tune ATIS in anyway? 85 00:04:26,480 --> 00:04:28,600 MAN: (VIA RADIO) Sumburgh, information Tango. 86 00:04:28,640 --> 00:04:32,720 Winds two-niner-zero at 3-4, gusting 4-7. 87 00:04:32,760 --> 00:04:33,760 Visibility... 88 00:04:33,800 --> 00:04:35,440 Guess it didn't get fried after all. 89 00:04:35,480 --> 00:04:38,840 Gusting 4-7. It's gonna get a bit rough on the way down. 90 00:04:41,240 --> 00:04:45,160 The winds at Sumburgh airport are blowing up to 47 knots, 91 00:04:45,200 --> 00:04:47,280 54 miles an hour. 92 00:04:49,080 --> 00:04:53,000 The crew will be facing strong gale force winds while landing. 93 00:04:58,160 --> 00:05:00,920 I travel by air a lot. It does get windy. 94 00:05:00,960 --> 00:05:03,160 We were expecting a little bit of turbulence on the way. 95 00:05:03,200 --> 00:05:05,520 We knew a flight of that size it's a small flight, 96 00:05:05,560 --> 00:05:07,680 you do feel turbulence, 97 00:05:07,720 --> 00:05:09,200 more than what you would on a bigger plane, 98 00:05:09,240 --> 00:05:10,720 but it was nothing unusual. 99 00:05:11,520 --> 00:05:13,000 The captain wants to be ready 100 00:05:13,040 --> 00:05:15,480 for any unpredictable weather thrown at them. 101 00:05:16,320 --> 00:05:18,520 Let's brief in case of a lightning strike. 102 00:05:18,560 --> 00:05:19,560 Copy that. 103 00:05:19,600 --> 00:05:22,480 OK, right. Instrument lights up full, 104 00:05:22,520 --> 00:05:24,040 in case we get blinded. 105 00:05:24,080 --> 00:05:26,440 Torches are here and here, on your side. 106 00:05:26,480 --> 00:05:29,480 And the emergency elevator trim switch is overhead. 107 00:05:29,520 --> 00:05:30,560 Any questions? 108 00:05:30,600 --> 00:05:31,800 No questions. 109 00:05:31,840 --> 00:05:34,800 The statistics suggest that a particular aircraft 110 00:05:34,840 --> 00:05:39,080 will probably get a lightning strike about 1.5 times a year. 111 00:05:40,520 --> 00:05:42,120 You don't know when it's coming of course, 112 00:05:42,160 --> 00:05:44,280 and the thing you're aware of 113 00:05:44,320 --> 00:05:49,440 is that these lightning strikes can affect the electronics 114 00:05:49,480 --> 00:05:50,920 and the avionics in the aircraft. 115 00:05:52,040 --> 00:05:56,560 Logan 67-80, fly heading 3-5-5. 116 00:05:56,600 --> 00:05:58,120 (VIA RADIO) Latest weather from Sumburgh, 117 00:05:58,160 --> 00:06:00,480 visibility 3,300 now. 118 00:06:00,520 --> 00:06:02,800 Moderate rain and snow. 119 00:06:02,840 --> 00:06:04,720 Runway is wet. 120 00:06:04,760 --> 00:06:07,840 3-5-5 for 67-80. Got the weather too, thanks. 121 00:06:08,640 --> 00:06:11,200 I'm gonna slow it down to 205, before we get into the chop. 122 00:06:11,240 --> 00:06:12,240 Roger that. 123 00:06:14,240 --> 00:06:17,400 The crew prepares the plane for the turbulence ahead. 124 00:06:18,880 --> 00:06:21,040 Let's get them buckled in, back there. 125 00:06:22,320 --> 00:06:24,400 (BEEPING SOUND) 126 00:06:28,880 --> 00:06:31,320 16 miles from Sumburgh Airport, 127 00:06:31,360 --> 00:06:35,200 Flight 67-80 turns onto its final approach to the runway. 128 00:06:47,360 --> 00:06:48,440 Take a look at that. 129 00:06:52,560 --> 00:06:53,760 I don't like it. 130 00:06:55,240 --> 00:06:58,520 There's some bad weather developing off the end of the runway. 131 00:06:58,560 --> 00:07:00,960 Approach, Logan 67-80. 132 00:07:01,000 --> 00:07:03,400 There's a big storm cell on radar just off the runway. 133 00:07:03,440 --> 00:07:05,040 We might need to discontinue. 134 00:07:05,080 --> 00:07:08,840 MAN: (VIA RADIO) 67-80, Roger. Let me know. 135 00:07:08,880 --> 00:07:12,880 All crews going into an airfield in these sorts of conditions 136 00:07:12,920 --> 00:07:17,440 will be wary of the thunderstorm's activity around them. 137 00:07:19,360 --> 00:07:21,560 The pilots consider their options. 138 00:07:22,480 --> 00:07:23,840 How much fuel do we have left? 139 00:07:25,160 --> 00:07:26,400 2,500 kilos. 140 00:07:26,440 --> 00:07:27,840 Do you want to head back to Aberdeen? 141 00:07:27,880 --> 00:07:30,320 Let's circle, make another attempt. 142 00:07:33,080 --> 00:07:35,080 They abandoned the approach 143 00:07:35,120 --> 00:07:39,200 when they saw a lot of precipitation on their weather radar 144 00:07:39,240 --> 00:07:40,360 just ahead of them, 145 00:07:41,919 --> 00:07:46,240 updrafts, downdrafts, wind shears, which are not predictable. 146 00:07:46,280 --> 00:07:50,600 So, you better go around and wait, or divert to another airport. 147 00:07:50,640 --> 00:07:52,880 Logan 67-80, we're gonna circle around, 148 00:07:52,920 --> 00:07:54,440 turning 1-8-0 for now. 149 00:07:55,320 --> 00:07:59,440 67-80, understood, maintain 2,000. 150 00:07:59,480 --> 00:08:01,320 He obviously made the decision 151 00:08:01,360 --> 00:08:02,360 that, at that time, 152 00:08:02,400 --> 00:08:04,560 he would just turn away from the airfield 153 00:08:04,600 --> 00:08:07,360 and probably allow that weather to pass through 154 00:08:07,400 --> 00:08:08,720 and then have another approach. 155 00:08:15,720 --> 00:08:18,800 As the pilots circle for another landing attempt... 156 00:08:20,320 --> 00:08:23,680 - (LIGHTENING) - Oh! Crap! 157 00:08:27,400 --> 00:08:29,080 It sounded like a gunshot. 158 00:08:29,720 --> 00:08:33,880 It was just a very short, sharp noise and a flash. 159 00:08:33,920 --> 00:08:35,000 I thought at that point 160 00:08:35,040 --> 00:08:36,800 that it was something that had happened to the engines. 161 00:08:38,000 --> 00:08:39,560 If you experience a lightning strike, 162 00:08:39,600 --> 00:08:42,720 especially at night, it's a very bright light. 163 00:08:42,760 --> 00:08:46,240 You can smell a burn smell, ozone smell, 164 00:08:46,280 --> 00:08:51,400 and that sure is frightening or fearsome to every crew. 165 00:08:52,920 --> 00:08:54,120 Circuit breakers look fine. 166 00:08:55,080 --> 00:08:56,240 After the lightning strike, 167 00:08:56,280 --> 00:08:59,560 you're obviously looking to see, "Have we been damaged? 168 00:08:59,600 --> 00:09:01,680 "Are the instruments still working correctly?" 169 00:09:01,720 --> 00:09:03,600 (SIGHS) I have control. 170 00:09:04,400 --> 00:09:06,360 But something's wrong. 171 00:09:06,400 --> 00:09:08,080 The controls feel really heavy. 172 00:09:09,960 --> 00:09:11,600 Damn it! The plane's not responding. 173 00:09:13,080 --> 00:09:17,400 There must be a degree of panic will set in 174 00:09:17,440 --> 00:09:19,400 when the controls are just not responding. 175 00:09:19,440 --> 00:09:20,680 The plane isn't responding. 176 00:09:20,720 --> 00:09:23,160 Mayday, Mayday, this is Loganair 67-80. 177 00:09:23,200 --> 00:09:24,200 We've been struck by lightning 178 00:09:24,240 --> 00:09:25,920 and are having control difficulties. 179 00:09:25,960 --> 00:09:27,240 Please clear the airspace. 180 00:09:29,160 --> 00:09:31,480 I knew that there was definitely something not right. 181 00:09:32,760 --> 00:09:34,240 I was terrified. 182 00:09:42,800 --> 00:09:48,520 Loganair Flight 67-80 is in distress 2,000 feet above the North Sea. 183 00:09:48,560 --> 00:09:51,080 Mayday, Mayday, this is Loganair 67-80. 184 00:09:51,120 --> 00:09:52,880 Please clear the airspace. 185 00:09:52,920 --> 00:09:54,720 67-80, copy. 186 00:09:54,760 --> 00:09:58,360 If you can, souls on board and fuel remaining? 187 00:09:58,400 --> 00:10:02,240 33 souls on board, 2,500 kilograms of fuel. 188 00:10:02,280 --> 00:10:04,400 Copy. All options are available. 189 00:10:04,440 --> 00:10:06,320 Do you want to land or divert? 190 00:10:08,120 --> 00:10:10,280 Without knowing what's wrong with the plane... 191 00:10:10,320 --> 00:10:11,920 (GRUNTS) It's really fighting me. 192 00:10:12,600 --> 00:10:16,520 ..it's too risky to attempt landing in a storm at Sumburgh Airport. 193 00:10:17,360 --> 00:10:18,760 We should divert back to Aberdeen. 194 00:10:18,800 --> 00:10:20,320 - Better conditions. - Agreed. 195 00:10:20,360 --> 00:10:23,800 Aberdeen Airport is 190 miles away. 196 00:10:23,840 --> 00:10:25,960 Let's try climbing to 4,000. 197 00:10:27,040 --> 00:10:29,440 67-80, we're going to divert back to Aberdeen. 198 00:10:30,440 --> 00:10:33,720 Something's wrong. I can't get the plane to climb. 199 00:10:33,760 --> 00:10:34,880 How's your side? 200 00:10:35,840 --> 00:10:37,120 It's really heavy. 201 00:10:39,600 --> 00:10:41,560 Trim's not doing anything either. 202 00:10:41,600 --> 00:10:45,200 If you grab on the yoke and the airplane is not responding, 203 00:10:45,240 --> 00:10:47,080 they realised, "Hey, there's something wrong. 204 00:10:47,120 --> 00:10:48,280 "We need to do something." 205 00:10:53,560 --> 00:10:56,400 Finally, the crew catches a small break. 206 00:10:57,760 --> 00:10:59,120 Altitude is increasing. 207 00:10:59,920 --> 00:11:00,920 Keep on it. 208 00:11:03,000 --> 00:11:06,520 The plane is climbing, but not as quickly as it should be. 209 00:11:08,720 --> 00:11:10,440 The elevators might be damaged. 210 00:11:11,320 --> 00:11:15,000 In two minutes, the plane has barely climbed 2,000 feet. 211 00:11:15,840 --> 00:11:17,120 The first officer worries 212 00:11:17,160 --> 00:11:20,040 the lightning strike may have disabled their instruments. 213 00:11:20,600 --> 00:11:23,280 Aberdeen 67-80. What's our altitude? 214 00:11:24,760 --> 00:11:28,000 I show you approaching 4,000 feet. 215 00:11:28,040 --> 00:11:31,680 But the controller is getting the exact same readings as the crew. 216 00:11:33,320 --> 00:11:35,600 We're really not going anywhere fast. 217 00:11:35,640 --> 00:11:38,600 - Pull! - I'm almost all the way back. 218 00:11:38,640 --> 00:11:39,640 Let's face it. 219 00:11:39,680 --> 00:11:41,200 You can fly an aircraft without a compass. 220 00:11:41,240 --> 00:11:43,080 You can fly an aircraft without a radio. 221 00:11:43,120 --> 00:11:46,120 But you can't fly an aircraft without functioning controls. 222 00:11:47,760 --> 00:11:50,520 And then, the unthinkable happens. 223 00:11:51,440 --> 00:11:53,920 Oh, no! Come on! 224 00:11:53,960 --> 00:11:54,960 We're dropping! 225 00:11:57,760 --> 00:12:01,800 Flight 67-80 plunges uncontrollably towards the North Sea. 226 00:12:01,840 --> 00:12:02,960 (SCREAMING) 227 00:12:03,000 --> 00:12:04,480 The flight went into that nosedive, 228 00:12:04,520 --> 00:12:06,280 so we knew immediately that, 229 00:12:06,320 --> 00:12:08,360 that something wasn't right with the plane. 230 00:12:08,400 --> 00:12:10,200 (SCREAMING) 231 00:12:11,280 --> 00:12:14,240 MAN: (VIA RADIO) 67-80... 3,800 now. 232 00:12:14,800 --> 00:12:17,640 600. 3,400. 233 00:12:18,560 --> 00:12:20,720 The pilots wrestle with their controls 234 00:12:20,760 --> 00:12:25,000 as the plane speeds towards the water at 350 miles an hour. 235 00:12:26,360 --> 00:12:27,960 You're descending. 236 00:12:28,000 --> 00:12:31,280 2,000 feet, 1,800 feet. 237 00:12:34,280 --> 00:12:37,880 The dive was so fast you just felt like your heart was in your mouth. 238 00:12:37,920 --> 00:12:40,560 I had no idea how close we were to the sea. 239 00:12:40,600 --> 00:12:41,800 You couldn't see anything. 240 00:12:41,840 --> 00:12:43,080 It was just pitch black. 241 00:12:45,040 --> 00:12:47,080 It was terrifying. It was really scary. 242 00:12:48,880 --> 00:12:51,600 1,500 feet. You're descending. 243 00:12:53,080 --> 00:12:54,560 Nothing's working! 244 00:12:54,600 --> 00:12:56,560 Come on! 245 00:12:56,600 --> 00:12:58,560 Pull up! 246 00:13:01,200 --> 00:13:04,280 The airplane is less than ten seconds from impact. 247 00:13:06,760 --> 00:13:08,840 It must be incredibly frightening, 248 00:13:08,880 --> 00:13:11,720 because the pilots would be aware of their rate of descent. 249 00:13:11,760 --> 00:13:14,000 They would be aware of their altitude. 250 00:13:14,040 --> 00:13:17,240 And they would be aware of how much time left they had 251 00:13:17,280 --> 00:13:18,640 to affect a recovery. 252 00:13:18,680 --> 00:13:19,840 MAN: (VIA RADIO) 1,100. 253 00:13:20,600 --> 00:13:22,440 Speed. Speed! 254 00:13:23,000 --> 00:13:25,520 In a last-ditch effort to save the plane, 255 00:13:25,560 --> 00:13:27,680 the captain increases engine power. 256 00:13:36,760 --> 00:13:37,960 MALE PILOT: We're climbing! 257 00:13:40,000 --> 00:13:41,080 So, increasing the power 258 00:13:41,120 --> 00:13:43,280 may increase the amount of airflow over the wings 259 00:13:43,320 --> 00:13:44,920 and give you a little bit more lift 260 00:13:44,960 --> 00:13:47,280 to allow the aircraft to pull out of its descent. 261 00:13:51,560 --> 00:13:53,240 We were travelling at such a speed 262 00:13:53,280 --> 00:13:55,120 that when the plane started pulling up again 263 00:13:55,160 --> 00:13:58,680 it was a kind of a sensation of being on a roller coaster. 264 00:14:00,040 --> 00:14:01,760 It was definitely a relief to start climbing 265 00:14:01,800 --> 00:14:03,200 after that nose pitch. 266 00:14:04,960 --> 00:14:07,360 The pilots have avoided near catastrophe, 267 00:14:08,840 --> 00:14:12,960 but now they need get their plane back to Aberdeen safely. 268 00:14:13,000 --> 00:14:14,360 In the moments after that, 269 00:14:14,400 --> 00:14:17,640 we had a period of just terrible turbulence, 270 00:14:17,680 --> 00:14:19,720 the worst turbulence I've ever experienced. 271 00:14:22,000 --> 00:14:24,000 The man behind me started vomiting. 272 00:14:24,040 --> 00:14:25,040 Everybody was kind of... 273 00:14:25,080 --> 00:14:27,880 The flight was quite quiet though. It was kind of eerily quiet. 274 00:14:29,000 --> 00:14:31,160 Requesting fight level 2-4-0. 275 00:14:31,200 --> 00:14:33,160 67-80. Roger. 276 00:14:33,200 --> 00:14:36,120 Climb and maintain 2-4-0. 277 00:14:38,560 --> 00:14:40,040 The controls are working better now. 278 00:14:45,720 --> 00:14:47,600 MALE PILOT: Ladies and gentlemen, this is the captain... 279 00:14:48,160 --> 00:14:49,760 It was at that point the pilot came on 280 00:14:49,800 --> 00:14:51,640 and told us we'd been struck by lightning 281 00:14:51,680 --> 00:14:53,880 and we were, we were heading back to Aberdeen. 282 00:14:53,920 --> 00:14:56,720 We had some flight control issues. 283 00:14:56,760 --> 00:14:58,520 Everything is under control now. 284 00:14:58,560 --> 00:15:01,600 We'll be landing in Aberdeen in 15 minutes. 285 00:15:01,640 --> 00:15:04,000 And please expect to see some emergency services 286 00:15:04,040 --> 00:15:05,280 on the ground when we land. 287 00:15:06,280 --> 00:15:09,240 Not to panic. It's just a standard precaution. 288 00:15:10,000 --> 00:15:11,480 Thank you. 289 00:15:11,520 --> 00:15:14,440 When you go through a moment like that, you... 290 00:15:14,480 --> 00:15:16,400 yeah, you panic until you're on the ground. 291 00:15:21,000 --> 00:15:22,680 Let's fly a straight-in approach 292 00:15:24,120 --> 00:15:26,280 and get this plane on the ground as soon as possible. 293 00:15:37,120 --> 00:15:39,920 The pilots of Loganair Flight 67-80 294 00:15:39,960 --> 00:15:42,760 are on final approach to Aberdeen Airport. 295 00:15:44,040 --> 00:15:45,600 Aberdeen, 67-80, 296 00:15:45,640 --> 00:15:48,960 established on the localiser, runway 1-6. 297 00:15:49,000 --> 00:15:51,560 Not knowing which instruments they can trust, 298 00:15:51,600 --> 00:15:54,440 the pilots carefully configure the plane for landing. 299 00:15:55,240 --> 00:15:56,400 Flaps 35. 300 00:15:58,440 --> 00:15:59,680 Flaps 35. 301 00:16:01,160 --> 00:16:02,880 Control feels normal. 302 00:16:02,920 --> 00:16:05,560 Having avoided disaster twice already, 303 00:16:05,599 --> 00:16:09,119 their sole focus is to get the plane safely on the ground. 304 00:16:09,160 --> 00:16:13,680 130. Speed looks good. Decision height. 305 00:16:14,640 --> 00:16:16,240 Runway in sight. Continue. 306 00:16:16,960 --> 00:16:20,680 The pilot came on and told us we'd be expecting a normal landing 307 00:16:20,720 --> 00:16:23,040 but the emergency services would be on the runway, 308 00:16:23,079 --> 00:16:25,319 we weren't to be alarmed if we saw the lights. 309 00:16:37,840 --> 00:16:40,000 Alright, 50 knots. 310 00:16:40,040 --> 00:16:42,680 - Coming out of reverse. - Check. 311 00:16:45,720 --> 00:16:48,200 The landing was smooth in Aberdeen. 312 00:16:48,240 --> 00:16:50,240 I was just glad that we were on the ground. 313 00:16:50,840 --> 00:16:52,480 I'm happy to be on solid ground. 314 00:16:53,880 --> 00:16:55,200 - Me too. - Mmm... 315 00:16:55,240 --> 00:16:56,880 I burst out into tears. 316 00:16:56,920 --> 00:16:58,720 It was relief more probably than anything, 317 00:16:59,960 --> 00:17:02,080 a little bit of shock probably too. 318 00:17:07,560 --> 00:17:08,960 It's up to investigators 319 00:17:09,000 --> 00:17:12,800 at the Air Accidents Investigation Branch, or AAIB, 320 00:17:12,840 --> 00:17:14,560 to figure out what went wrong. 321 00:17:17,040 --> 00:17:21,520 David Miller is the Deputy Chief overseeing the investigation. 322 00:17:21,560 --> 00:17:25,040 I decided that this would be a full investigation, 323 00:17:25,080 --> 00:17:29,840 because of the closeness this aircraft came to disaster. 324 00:17:31,040 --> 00:17:34,280 We then dispatched a small team of investigators 325 00:17:34,320 --> 00:17:37,200 to the operator's base to interview the crew 326 00:17:37,240 --> 00:17:39,240 and to examine the aircraft. 327 00:17:41,560 --> 00:17:44,920 Very quickly, the flight data and cockpit voice recorders 328 00:17:44,960 --> 00:17:47,520 are recovered from the Saab 2,000. 329 00:17:47,560 --> 00:17:48,560 Great work. 330 00:17:50,520 --> 00:17:52,040 Let's hope they can provide some answers. 331 00:17:52,080 --> 00:17:53,240 Let's hope. 332 00:17:53,280 --> 00:17:55,080 The normal process for investigation 333 00:17:55,120 --> 00:17:56,800 is the investigators take the recorders, 334 00:17:56,840 --> 00:17:59,160 the cockpit voice recorder and the flight data recorder, 335 00:17:59,200 --> 00:18:01,560 bring them back to the laboratories and recover the data. 336 00:18:02,200 --> 00:18:03,560 It looks to be in pretty good shape. 337 00:18:04,160 --> 00:18:05,920 Unusually so, yeah. 338 00:18:07,080 --> 00:18:08,960 Investigators need to confirm 339 00:18:09,000 --> 00:18:11,320 the crew's report of a lightning strike 340 00:18:11,360 --> 00:18:13,120 as well as the flight attendant's account 341 00:18:13,160 --> 00:18:16,160 of seeing an orb of light pass through the cabin. 342 00:18:20,360 --> 00:18:23,600 Ball lightning is a rare and little understood phenomenon 343 00:18:23,640 --> 00:18:27,000 known to precede lightning strikes inside airplanes. 344 00:18:32,680 --> 00:18:33,680 Right. 345 00:18:34,480 --> 00:18:35,960 Well, there's no damage on the wing tip. 346 00:18:36,000 --> 00:18:37,000 Mm-hmm. 347 00:18:39,440 --> 00:18:42,480 Lightning can strike more or less anywhere on an aircraft, 348 00:18:42,520 --> 00:18:44,920 but it tends to strike on the leading edge of the wings 349 00:18:44,960 --> 00:18:47,160 or the radome at the front of the aircraft. 350 00:18:52,080 --> 00:18:54,000 There's soot marks on the radome. 351 00:18:55,280 --> 00:18:57,920 Investigators see signs of a lightning strike 352 00:18:57,960 --> 00:18:59,600 on the nose of the aircraft. 353 00:19:00,240 --> 00:19:02,280 It looks like some surface damage as well. 354 00:19:02,320 --> 00:19:03,680 - Yeah? - Yeah. 355 00:19:04,400 --> 00:19:08,360 The point of strike will often leave scarring, 356 00:19:08,400 --> 00:19:12,320 localised burning, sometimes a small hole. 357 00:19:12,360 --> 00:19:14,400 Right. Let's see where it exited the aircraft then. 358 00:19:22,240 --> 00:19:23,600 Elevators look fine. 359 00:19:28,640 --> 00:19:29,840 Hang on. 360 00:19:32,120 --> 00:19:33,920 Have a look at that exhaust cone. 361 00:19:35,560 --> 00:19:36,560 Oh, yeah. 362 00:19:38,920 --> 00:19:41,560 That's where the lightning exited. Look at it. 363 00:19:41,600 --> 00:19:43,520 Parts of it are completely melted. 364 00:19:43,560 --> 00:19:45,040 And there was a little bit of burning damage 365 00:19:45,080 --> 00:19:46,240 both to the front of the aircraft 366 00:19:46,280 --> 00:19:48,600 and the exit point of the lightning strike, 367 00:19:48,640 --> 00:19:50,240 which was at the very tail of the aircraft 368 00:19:50,280 --> 00:19:53,320 where the auxiliary power unit exhaust was placed. 369 00:19:54,360 --> 00:19:57,120 Oh! Crap! 370 00:19:57,160 --> 00:20:00,680 The team now knows how the lightning struck the plane. 371 00:20:03,560 --> 00:20:05,360 The controls feel really heavy. 372 00:20:06,160 --> 00:20:07,760 So, one of the first things to go and have a look at, 373 00:20:07,800 --> 00:20:09,720 what was the effect of the lightning strike? 374 00:20:09,760 --> 00:20:12,560 Were the systems damaged? Were there malfunctions? 375 00:20:17,160 --> 00:20:18,400 OK, you ready? 376 00:20:18,440 --> 00:20:21,440 The AAIB tests the plane's flight controls 377 00:20:21,480 --> 00:20:23,160 o see if they're working. 378 00:20:23,200 --> 00:20:25,080 MAN: (VIA RADIO) OK. Check the rudder. 379 00:20:31,800 --> 00:20:34,040 Looks good. How about the elevators? 380 00:20:40,720 --> 00:20:43,720 Yeah, elevators are working too. Everything checks out. 381 00:20:44,360 --> 00:20:46,520 Investigators are perplexed. 382 00:20:46,560 --> 00:20:49,120 If the plane was functioning properly, 383 00:20:49,160 --> 00:20:51,480 why did it become so difficult to control 384 00:20:51,520 --> 00:20:53,120 after the lightning strike? 385 00:20:54,800 --> 00:20:56,320 There were no abnormalities, 386 00:20:56,360 --> 00:20:58,840 no system defects that we could find either structurally 387 00:20:58,880 --> 00:21:00,080 or within the avionics. 388 00:21:00,880 --> 00:21:02,240 Beyond that, it looked like 389 00:21:02,280 --> 00:21:04,440 a completely normal, serviceable aircraft. 390 00:21:08,280 --> 00:21:12,920 AAIB investigators interview the pilots of Flight 67-80. 391 00:21:14,600 --> 00:21:16,960 When we're fortunate enough, as in these circumstances, 392 00:21:17,000 --> 00:21:18,480 to have a surviving flight crew, 393 00:21:18,520 --> 00:21:20,760 then their recollections are really important for us 394 00:21:20,800 --> 00:21:25,080 to understand exactly how the event progressed from their perspective. 395 00:21:26,320 --> 00:21:28,680 So, what happened after the lightning struck the plane? 396 00:21:28,720 --> 00:21:31,720 After the lightning struck, the autopilot disconnected. 397 00:21:39,960 --> 00:21:40,960 I have control. 398 00:21:42,000 --> 00:21:45,520 The crew of the aircraft became aware 399 00:21:45,560 --> 00:21:47,240 fairly shortly after the lightning 400 00:21:47,280 --> 00:21:50,000 strike that the aircraft wasn't responding as they expected, 401 00:21:50,040 --> 00:21:51,160 to their flight control inputs. 402 00:21:51,840 --> 00:21:52,960 And then what happened? 403 00:21:54,720 --> 00:21:57,320 Well, we had control issues. 404 00:21:57,360 --> 00:21:58,600 The plane wouldn't climb. 405 00:21:58,640 --> 00:22:01,120 We tried everything and the plane wasn't responding. 406 00:22:03,920 --> 00:22:06,640 The pilot flying was finding that he was having to put 407 00:22:06,680 --> 00:22:10,640 an increasingly strong backward effort on the control column 408 00:22:10,680 --> 00:22:12,280 to raise the nose of the aircraft. 409 00:22:12,880 --> 00:22:15,160 I can't get the plane to climb. How's your side? 410 00:22:16,360 --> 00:22:17,360 It's really heavy. 411 00:22:18,920 --> 00:22:20,800 Trim's not doing anything either. 412 00:22:20,840 --> 00:22:23,320 And the aircraft wasn't responding the way that he expected. 413 00:22:24,040 --> 00:22:25,120 And then? 414 00:22:26,840 --> 00:22:28,560 And then we entered a steep nosedive. 415 00:22:28,600 --> 00:22:30,920 And the control issues continued. 416 00:22:38,720 --> 00:22:40,080 Nothing's working! 417 00:22:40,120 --> 00:22:41,120 Come on! 418 00:22:42,240 --> 00:22:44,160 Pull up! 419 00:22:44,680 --> 00:22:46,960 Speed. Speed! 420 00:22:53,760 --> 00:22:55,640 It wasn't until after we'd increased power 421 00:22:55,680 --> 00:22:57,400 that we were able to get the aircraft under control. 422 00:22:59,640 --> 00:23:00,760 Really? 423 00:23:00,800 --> 00:23:03,640 Why did the crew believe that they had control restrictions 424 00:23:03,680 --> 00:23:05,000 and control problems, 425 00:23:05,040 --> 00:23:08,200 when in fact testing of the aircraft showed there were no faults? 426 00:23:16,880 --> 00:23:18,640 Let's have a listen, shall we? 427 00:23:18,680 --> 00:23:20,240 Puzzled by the crew's account 428 00:23:20,280 --> 00:23:22,880 of the incident on board flight 67-80, 429 00:23:23,560 --> 00:23:27,360 investigators turn to the cockpit voice recorder for answers. 430 00:23:27,400 --> 00:23:29,760 It will answer many questions 431 00:23:29,800 --> 00:23:31,920 as to why things were happening the way they were 432 00:23:31,960 --> 00:23:33,880 and how the crew were working together 433 00:23:33,920 --> 00:23:34,920 and interacting together. 434 00:23:36,320 --> 00:23:37,640 WOMAN: (VIA RECORDING) Aberdeen ground, 435 00:23:37,680 --> 00:23:40,440 67-80 taxiing on Whiskey for parking stand seven. 436 00:23:41,320 --> 00:23:43,160 But something's not right. 437 00:23:43,760 --> 00:23:44,760 Aberdeen? 438 00:23:46,000 --> 00:23:47,840 No. This is from when they landed back at Aberdeen. 439 00:23:47,880 --> 00:23:50,000 Right, can you stop it and go back to the top 440 00:23:50,040 --> 00:23:51,200 and play it again, please? 441 00:23:54,760 --> 00:23:56,080 WOMAN: (VIA RECORDING) Aberdeen ground, 442 00:23:56,120 --> 00:23:59,200 67-80 taxiing on Whiskey for parking stand seven. 443 00:23:59,760 --> 00:24:01,080 That's all there is. 444 00:24:02,400 --> 00:24:04,120 Well, that's not gonna help us very much now, is it? 445 00:24:06,200 --> 00:24:10,840 The CVR has recorded over the critical moments of the flight. 446 00:24:10,880 --> 00:24:13,720 It's a major setback for the investigation. 447 00:24:13,760 --> 00:24:15,520 We discovered that the cockpit voice recorder, 448 00:24:15,560 --> 00:24:17,400 which only lasts for 30 minutes, 449 00:24:17,440 --> 00:24:20,480 has been overwritten by subsequent events, 450 00:24:20,520 --> 00:24:23,320 so there was no record of the crew conversation 451 00:24:23,360 --> 00:24:25,200 and how they interacted with each other. 452 00:24:28,000 --> 00:24:30,240 And so you have to look elsewhere for the information. 453 00:24:35,560 --> 00:24:37,560 Right. This is what we know so far. 454 00:24:37,600 --> 00:24:40,640 The lightning struck, the autopilot disconnected, 455 00:24:40,680 --> 00:24:42,160 they had control problems. 456 00:24:42,200 --> 00:24:45,520 Then, the plane did a nosedive. 457 00:24:45,560 --> 00:24:47,880 - Well, let's review the data. - Hmm. 458 00:24:48,960 --> 00:24:52,080 Will the data recorder provide the answers they need 459 00:24:52,120 --> 00:24:53,480 to solve this case? 460 00:24:54,800 --> 00:24:58,840 Flight data recorders often add a level of detail 461 00:24:58,880 --> 00:25:01,600 that simply can't be gained from, from the witnesses themselves, 462 00:25:01,640 --> 00:25:03,240 and crucially, 463 00:25:03,280 --> 00:25:06,000 quite often the information that's gathered from a recording device 464 00:25:06,040 --> 00:25:07,880 offers a slightly different perspective 465 00:25:07,920 --> 00:25:10,040 to what we might get from personal recollections. 466 00:25:11,920 --> 00:25:13,440 Stop. 467 00:25:13,480 --> 00:25:15,880 This is where the lightning struck at 2,000 feet. 468 00:25:16,520 --> 00:25:18,320 Right, and then for the next 2.5 minutes, 469 00:25:18,360 --> 00:25:21,200 there's a slow uneven climb to 4,000 feet. 470 00:25:22,320 --> 00:25:24,440 And then they are in a very steep nosedive 471 00:25:24,480 --> 00:25:27,000 for 20 seconds towards the North Sea. 472 00:25:30,560 --> 00:25:32,560 That's 9,500 feet per minute. 473 00:25:33,720 --> 00:25:35,120 Investigators are struck 474 00:25:35,160 --> 00:25:36,880 by how close the flight came 475 00:25:36,920 --> 00:25:39,120 to total disaster. 476 00:25:39,160 --> 00:25:40,960 It was seven seconds 477 00:25:41,000 --> 00:25:42,640 from plunging into the sea 478 00:25:42,680 --> 00:25:45,280 before they finally managed to pull out at 1,100 feet. 479 00:25:46,320 --> 00:25:48,240 The aircraft had a very high rate of descent 480 00:25:48,280 --> 00:25:50,560 in the moments before it reached that height. 481 00:25:50,600 --> 00:25:54,400 And so we were really very close to a very serious accident. 482 00:25:55,520 --> 00:25:58,720 What were the pilots doing to recover from the dive? 483 00:26:00,320 --> 00:26:02,520 Look at the control column data. 484 00:26:03,360 --> 00:26:04,920 Right after the lightning struck, 485 00:26:04,960 --> 00:26:09,240 the crew pulled back on the control column to pitch the nose up. 486 00:26:12,160 --> 00:26:13,160 I have control. 487 00:26:17,360 --> 00:26:19,000 The controls feel really heavy. 488 00:26:20,200 --> 00:26:21,240 Look at the line. 489 00:26:21,280 --> 00:26:23,040 I mean, they're having a very difficult time 490 00:26:23,080 --> 00:26:24,720 getting that plane to climb. 491 00:26:25,360 --> 00:26:26,520 We know from the data 492 00:26:26,560 --> 00:26:30,080 that the aircraft climbed to around about 4,000 feet. 493 00:26:30,120 --> 00:26:32,800 The pilot was finding that he was having to put 494 00:26:32,840 --> 00:26:36,400 an increasingly strong backward effort on the control column 495 00:26:36,440 --> 00:26:38,160 to raise the nose of the aircraft. 496 00:26:38,960 --> 00:26:41,560 And the aircraft wasn't responding the way that he expected. 497 00:26:42,880 --> 00:26:47,320 The FDR data confirms the pilots were tackling a control problem. 498 00:26:47,360 --> 00:26:48,960 But why? 499 00:26:49,000 --> 00:26:51,840 The Captain said they were also applying pitch trim. 500 00:26:54,920 --> 00:26:58,080 Pitch trim moves the tail elevators up and down 501 00:26:58,120 --> 00:27:00,360 to maintain the pitch of the aircraft. 502 00:27:02,840 --> 00:27:05,080 Could we take a look at the pitch trim data, please? 503 00:27:05,120 --> 00:27:06,200 Right. 504 00:27:09,200 --> 00:27:12,200 Investigators make a puzzling discovery. 505 00:27:12,240 --> 00:27:13,240 Look at that. 506 00:27:14,040 --> 00:27:16,400 The elevators are trying to get the nose to pitch down 507 00:27:16,440 --> 00:27:17,560 instead of up. 508 00:27:19,160 --> 00:27:20,800 After the lightning strike, 509 00:27:20,840 --> 00:27:24,160 some unknown force was fighting the pilots' inputs 510 00:27:24,200 --> 00:27:27,320 to both the control column and the pitch trim. 511 00:27:27,360 --> 00:27:29,320 It's very difficult to imagine what, 512 00:27:29,360 --> 00:27:32,400 let's say, an 80-pound force feels like. 513 00:27:34,160 --> 00:27:37,280 Normal control pressures are much, much lower 514 00:27:37,320 --> 00:27:40,160 that, in the order of sort of ten to 20 pounds. 515 00:27:40,200 --> 00:27:42,600 So, an 80 pound pull is really extraordinary 516 00:27:42,640 --> 00:27:44,320 and very difficult to maintain. 517 00:27:47,000 --> 00:27:50,200 Something's wrong. I can't get the plane to climb. 518 00:27:50,240 --> 00:27:51,480 How's your side? 519 00:27:52,440 --> 00:27:53,680 It's really heavy. 520 00:27:54,960 --> 00:27:56,440 Trim's not doing anything either. 521 00:27:57,640 --> 00:27:59,680 We found that although the pilots were applying 522 00:27:59,720 --> 00:28:02,560 a significant nose up pitch control input 523 00:28:02,600 --> 00:28:05,320 by pulling the stick back towards them, 524 00:28:05,360 --> 00:28:08,080 the aircraft was actually trimmed nose down. 525 00:28:09,120 --> 00:28:12,120 Whatever was trimming the pitch control system 526 00:28:12,160 --> 00:28:14,640 was effectively overcoming the effort of the pilots. 527 00:28:19,560 --> 00:28:23,040 The crew said the lightning struck, 528 00:28:23,080 --> 00:28:28,120 the autopilot disconnected, and then they had control problems. 529 00:28:28,160 --> 00:28:29,200 Right. 530 00:28:29,240 --> 00:28:31,040 Could we take a look at the autopilot data, please? 531 00:28:33,040 --> 00:28:36,240 Finally, the team zeros in on the answer. 532 00:28:39,160 --> 00:28:42,200 The autopilot was on almost the entire time. 533 00:28:44,120 --> 00:28:46,200 The pilots themselves were very clear in their recollection 534 00:28:46,240 --> 00:28:47,880 that it had disengaged. 535 00:28:50,320 --> 00:28:51,320 All of the evidence we had 536 00:28:51,360 --> 00:28:54,680 indicated the autopilot had in fact remained engaged. 537 00:28:54,720 --> 00:28:57,240 It's no wonder the pilot had control problems. 538 00:28:57,280 --> 00:28:59,920 The autopilot was set to keep the plane at 2,000 feet. 539 00:28:59,960 --> 00:29:02,840 Right. And whenever the pilots tried to get the plane to climb, 540 00:29:02,880 --> 00:29:05,600 the autopilot would engage and bring the plane back down. 541 00:29:05,640 --> 00:29:07,480 Back to its assigned altitude. 542 00:29:08,320 --> 00:29:11,920 Investigators discover that after the lightning strike, 543 00:29:11,960 --> 00:29:15,160 the pilots were in a tug of war with the plane. 544 00:29:15,200 --> 00:29:17,560 I can't get the plane to climb. How's your side? 545 00:29:18,760 --> 00:29:20,040 FEMALE PILOT: It's really heavy. 546 00:29:21,760 --> 00:29:27,120 So, we then had to look at why did the crew misunderstand 547 00:29:27,160 --> 00:29:28,360 the status of the aircraft? 548 00:29:35,120 --> 00:29:39,720 The AAIB contacts the Captain of flight 67-80 549 00:29:39,760 --> 00:29:43,440 to better understand why he thought the autopilot disconnected 550 00:29:43,480 --> 00:29:44,960 when, in fact, it hadn't. 551 00:29:45,880 --> 00:29:50,080 The Saab 340? OK. Thanks. 552 00:29:53,600 --> 00:29:56,720 He said he assumed the lightning would disable the autopilot. 553 00:29:58,160 --> 00:30:01,000 The team learns the pilot trained for lightning strikes 554 00:30:01,040 --> 00:30:04,440 on another airplane, the Saab 340. 555 00:30:04,480 --> 00:30:07,840 To change from Saab 340 to the Saab 2,000, 556 00:30:07,880 --> 00:30:11,480 you can say it's like changing from a motorbike to a bus. 557 00:30:11,520 --> 00:30:15,400 All systems are different. Performance is different. 558 00:30:16,920 --> 00:30:20,120 You're flying a totally different airplane. 559 00:30:21,680 --> 00:30:24,400 During the training on the Saab 340, 560 00:30:24,440 --> 00:30:28,960 the commander had experienced a simulated lightning strike 561 00:30:29,000 --> 00:30:30,120 to that aircraft, 562 00:30:30,160 --> 00:30:32,160 which caused both generators to fail 563 00:30:33,280 --> 00:30:34,960 and, in doing so, 564 00:30:35,000 --> 00:30:37,080 would cause the autopilot to disconnect. 565 00:30:38,000 --> 00:30:39,120 I have control. 566 00:30:40,520 --> 00:30:43,760 So, when the lightning strike happened for real, 567 00:30:43,800 --> 00:30:46,960 his first thoughts were, "The autopilot has failed". 568 00:30:48,040 --> 00:30:49,400 The controls feel really heavy. 569 00:30:50,160 --> 00:30:52,160 "I must control the aircraft myself". 570 00:30:52,880 --> 00:30:55,840 And in fact, the lightning strike had had minimal effect 571 00:30:55,880 --> 00:30:57,000 on the aircraft. 572 00:30:58,000 --> 00:31:01,240 Would you pull up the control data column again, please? 573 00:31:01,280 --> 00:31:04,200 If the lightning didn't disconnect the autopilot, 574 00:31:04,240 --> 00:31:08,400 investigators wonder why it remained engaged for more than two minutes 575 00:31:08,440 --> 00:31:10,880 as the pilots struggled with the controls? 576 00:31:10,920 --> 00:31:14,200 Wouldn't the force applied to the control column 577 00:31:14,240 --> 00:31:18,120 and the pitch trim have overridden the autopilot? 578 00:31:22,280 --> 00:31:23,640 Now, in most aircraft, 579 00:31:23,680 --> 00:31:25,760 if the pilot intervenes on the controls 580 00:31:25,800 --> 00:31:29,280 and tries to apply a force against the autopilot, 581 00:31:29,320 --> 00:31:31,440 the autopilot is designed to disengage. 582 00:31:32,800 --> 00:31:33,800 One way of thinking about this 583 00:31:33,840 --> 00:31:35,640 is to imagine you're driving down the highway 584 00:31:35,680 --> 00:31:37,680 in a car on cruise control 585 00:31:37,720 --> 00:31:40,320 and you're getting close to a car in front of you, 586 00:31:40,360 --> 00:31:42,080 so you press the brake. 587 00:31:42,120 --> 00:31:45,040 And what you expect to happen is for the car to slow down. 588 00:31:45,080 --> 00:31:48,840 You don't expect the cruise control to oppose the brake 589 00:31:48,880 --> 00:31:51,760 and add more power to maintain 65 miles an hour, 590 00:31:51,800 --> 00:31:53,920 but that's essentially what was happening in this case. 591 00:31:56,840 --> 00:32:00,840 The autopilot was attempting to keep the plane at 2,000 feet, 592 00:32:00,880 --> 00:32:03,800 despite all attempts by the crew to climb. 593 00:32:03,840 --> 00:32:07,440 It says here, "Applying an override force to the column 594 00:32:07,480 --> 00:32:09,840 "will not cause the autopilot to disengage". 595 00:32:11,040 --> 00:32:12,840 In the Saab 2,000, 596 00:32:12,880 --> 00:32:14,720 the autopilot would not disconnect 597 00:32:14,760 --> 00:32:17,720 when you exert force on the control columns. 598 00:32:18,440 --> 00:32:20,120 There's more. 599 00:32:20,160 --> 00:32:22,080 Pressing the main pitch trim switches 600 00:32:22,120 --> 00:32:26,160 also has no effect to cause the autopilot to disengage. 601 00:32:27,720 --> 00:32:29,800 The team is surprised to discover 602 00:32:29,840 --> 00:32:34,280 there is no force override for the autopilot in the Saab 2,000. 603 00:32:36,200 --> 00:32:37,920 Something's wrong. 604 00:32:37,960 --> 00:32:39,600 I can't get the plane to climb. 605 00:32:39,640 --> 00:32:42,440 One thing the pilot would have done is as he pulled back 606 00:32:42,480 --> 00:32:44,200 and feeling the force on the control column, 607 00:32:44,240 --> 00:32:46,800 he would have used the switches on the control column 608 00:32:46,840 --> 00:32:49,520 to apply trim in the appropriate way. 609 00:32:49,560 --> 00:32:50,720 MALE PILOT: How's your side? 610 00:32:52,040 --> 00:32:53,200 It's really heavy. 611 00:32:56,440 --> 00:32:58,360 Trim's not doing anything either. 612 00:32:58,400 --> 00:32:59,920 But when the autopilot's engaged, 613 00:32:59,960 --> 00:33:03,920 in this model of aircraft, the trim switches are inhibited. 614 00:33:03,960 --> 00:33:06,800 So, no matter how much they selected those trim switches, 615 00:33:06,840 --> 00:33:08,800 they were having absolutely no effect. 616 00:33:13,159 --> 00:33:17,400 Investigators soon discover that the Saab 2,000 is unique. 617 00:33:17,440 --> 00:33:18,440 Look at that. 618 00:33:20,080 --> 00:33:21,080 There. 619 00:33:21,120 --> 00:33:22,960 It's one of the few planes in existence 620 00:33:23,000 --> 00:33:25,360 that doesn't have an autopilot override. 621 00:33:25,400 --> 00:33:28,920 Every plane has an autopilot override function, 622 00:33:28,960 --> 00:33:31,239 except for the Saab 2,000. 623 00:33:34,679 --> 00:33:36,199 It just had a different design 624 00:33:36,239 --> 00:33:38,080 to all the other aircraft we were aware of. 625 00:33:38,800 --> 00:33:41,239 And really, to discover that the autopilot 626 00:33:41,280 --> 00:33:44,719 had greater authority than the human pilots 627 00:33:44,760 --> 00:33:46,280 was a bit of a revelation for us. 628 00:33:49,360 --> 00:33:50,920 It still doesn't explain 629 00:33:50,960 --> 00:33:53,760 why the crew didn't know the autopilot was on 630 00:33:53,800 --> 00:33:55,440 almost the entire time. 631 00:33:56,960 --> 00:33:59,400 Wouldn't there be some sort of indicator in the cockpit? 632 00:33:59,440 --> 00:34:01,560 Yeah. I'll show you. Look over here. 633 00:34:03,360 --> 00:34:07,840 When the autopilot is connected, that will be a green AP. 634 00:34:09,160 --> 00:34:10,600 Well, what does the control panel look like 635 00:34:10,640 --> 00:34:12,560 when the autopilot goes off? 636 00:34:12,600 --> 00:34:13,760 Like this. 637 00:34:18,920 --> 00:34:21,120 When that autopilot pilot is not connected, 638 00:34:21,160 --> 00:34:24,240 it will be a white AP, but the letters AP remain. 639 00:34:25,000 --> 00:34:26,280 - That's it? - That's it. 640 00:34:26,320 --> 00:34:27,600 It just goes from green to white. 641 00:34:29,120 --> 00:34:32,720 One could argue whether that visual clue 642 00:34:32,760 --> 00:34:37,640 is enough to warn the crew of the status of the autopilot. 643 00:34:38,600 --> 00:34:39,640 I have control. 644 00:34:41,200 --> 00:34:44,320 It's not as if the AP disappears when it's not engaged 645 00:34:44,360 --> 00:34:45,840 and appears when it is engaged. 646 00:34:46,680 --> 00:34:49,200 Oh, no. Come on! 647 00:34:49,240 --> 00:34:50,360 We're dropping! 648 00:34:50,400 --> 00:34:53,800 But all we have here is a colour change between green and white. 649 00:34:53,840 --> 00:34:56,280 And that sometimes is very difficult to perceive 650 00:34:57,120 --> 00:35:00,120 when you're in a high-stress situation. 651 00:35:03,760 --> 00:35:07,200 Investigators believe that the autopilot visual indication 652 00:35:07,240 --> 00:35:10,040 might have been too small for the pilots to see 653 00:35:10,080 --> 00:35:12,320 as they struggled to control their plane. 654 00:35:18,240 --> 00:35:20,320 Surely there would have been aural warnings? 655 00:35:22,880 --> 00:35:23,920 Yes. Right here. 656 00:35:23,960 --> 00:35:26,960 It says, "The plane's computer would have sounded a caution chime". 657 00:35:28,280 --> 00:35:31,960 Even if the pilots missed the visual indications for the autopilot, 658 00:35:32,000 --> 00:35:34,120 caution chimes would have alerted them 659 00:35:34,160 --> 00:35:36,040 when they adjusted the pitch trim. 660 00:35:37,480 --> 00:35:39,800 The Captain never said anything about hearing any chimes. 661 00:35:39,840 --> 00:35:41,920 Right. So, what's going on then? 662 00:35:45,200 --> 00:35:48,440 MAN: (VIA RADIO) 67-80, 3,800 now. 663 00:35:50,560 --> 00:35:52,320 If they are trimming against the autopilot 664 00:35:52,360 --> 00:35:53,840 for more than ten seconds, 665 00:35:53,880 --> 00:35:58,920 a chime will announce to say that there is a pitch mis-trim situation. 666 00:35:58,960 --> 00:36:00,480 (ALARM GOING OFF) 667 00:36:01,280 --> 00:36:03,520 We see from the data that it's highly likely 668 00:36:03,560 --> 00:36:05,520 that the alerts would have occurred, 669 00:36:05,560 --> 00:36:07,280 but the crew don't recall having heard them. 670 00:36:07,960 --> 00:36:09,440 Nothing's working! 671 00:36:09,480 --> 00:36:10,520 Come on. 672 00:36:10,560 --> 00:36:13,520 So, why did the pilots of Flight 67-80 673 00:36:13,560 --> 00:36:17,680 ignore all warnings telling them that the autopilot was in control? 674 00:36:20,240 --> 00:36:24,040 AAIB investigators have learned that after a lightning strike, 675 00:36:24,080 --> 00:36:26,800 the crew of Loganair Flight 67-80 676 00:36:28,840 --> 00:36:31,080 didn't recall hearing audible warnings 677 00:36:31,120 --> 00:36:35,400 that the autopilot was engaged and set to maintain 2,000 feet. 678 00:36:37,240 --> 00:36:38,840 Lightning struck the plane 679 00:36:39,600 --> 00:36:43,880 and for 2.5 minutes the crew struggled with the controls 680 00:36:43,920 --> 00:36:45,080 to get the plane to climb. 681 00:36:45,120 --> 00:36:46,120 Right. 682 00:36:46,160 --> 00:36:47,400 They were so distracted by that, 683 00:36:47,440 --> 00:36:50,520 they failed to see what was really going on. 684 00:36:51,360 --> 00:36:54,960 Could the stress have affected their perception of the situation? 685 00:37:00,320 --> 00:37:03,360 We have to bear in mind, of course, this was at night, 686 00:37:03,400 --> 00:37:06,360 in turbulent, poor weather, heavy rain, 687 00:37:08,400 --> 00:37:11,280 and the lightning strike would have been really quite bright, 688 00:37:12,080 --> 00:37:13,840 and the noise would have been alarming. 689 00:37:17,560 --> 00:37:19,600 So, it's sort of understandable 690 00:37:19,640 --> 00:37:23,200 that their performance was degraded, because of the stress situation. 691 00:37:24,240 --> 00:37:25,320 And I have control. 692 00:37:25,360 --> 00:37:26,720 (ALARM GOING OFF) 693 00:37:26,760 --> 00:37:29,560 A couple of things happen when we get stressed. 694 00:37:29,600 --> 00:37:33,000 We tend to focus on fewer and fewer things, 695 00:37:33,040 --> 00:37:36,360 and we tend to not notice the other things, 696 00:37:36,400 --> 00:37:41,040 and that can be either visual cues or auditory cues. 697 00:37:41,080 --> 00:37:42,840 So, we get what's called, "Cognitive tunnelling," 698 00:37:42,880 --> 00:37:44,960 and one aspect of that is an intentional deafness 699 00:37:45,000 --> 00:37:48,840 so, an alert might occur, but we might not hear it. 700 00:37:48,880 --> 00:37:50,360 (ALARM GOING OFF) 701 00:37:51,560 --> 00:37:52,920 It's very difficult for a crew 702 00:37:52,960 --> 00:37:57,160 to break the vicious circle of cognitive tunnelling 703 00:37:57,200 --> 00:37:59,960 where they're concentrating on one event 704 00:38:00,000 --> 00:38:02,480 and not looking at the bigger picture. 705 00:38:03,400 --> 00:38:05,440 The controls feel really heavy. 706 00:38:05,480 --> 00:38:08,280 But if the pilots were suffering from cognitive tunnelling, 707 00:38:09,640 --> 00:38:12,440 how were they able to regain control of the plane? 708 00:38:17,320 --> 00:38:19,000 MAN: OK. Look at this. 709 00:38:19,040 --> 00:38:22,960 The AAIB makes one last horrifying discovery. 710 00:38:23,800 --> 00:38:27,400 The only reason the autopilot ever disengaged 711 00:38:28,920 --> 00:38:32,480 was because of a random glitch in the plane's computer system. 712 00:38:34,440 --> 00:38:35,560 The reason for the disconnection 713 00:38:35,600 --> 00:38:38,920 was that there was a momentary loss of data to the air data computer. 714 00:38:38,960 --> 00:38:40,840 And we know that's one of the conditions 715 00:38:40,880 --> 00:38:42,440 that would cause the autopilot to disconnect. 716 00:38:42,480 --> 00:38:44,760 And that's what caused it to disconnect in this case. 717 00:38:46,200 --> 00:38:51,120 Had the autopilot disconnected more than seven seconds later, 718 00:38:51,160 --> 00:38:54,080 the airplane would have gone into the ocean, 719 00:38:54,120 --> 00:38:57,000 in a dive at over 300 knots. 720 00:38:58,400 --> 00:39:01,040 This wasn't a fatal accident by pure luck. 721 00:39:02,840 --> 00:39:05,400 Investigators believe they finally understand 722 00:39:05,440 --> 00:39:10,160 what caused the terrifying incident on board Loganair Flight 67-80. 723 00:39:15,560 --> 00:39:19,560 While circling away from a bad storm at Sumburgh Airport... 724 00:39:19,600 --> 00:39:20,600 Roger that. 725 00:39:20,640 --> 00:39:22,960 We'll wait until the storm's over. 726 00:39:23,000 --> 00:39:25,120 ..the crew is startled and disoriented 727 00:39:25,160 --> 00:39:26,800 by a lightning strike. 728 00:39:26,840 --> 00:39:28,640 (SCREAMING) 729 00:39:28,680 --> 00:39:30,200 In a moment of high stress, 730 00:39:30,240 --> 00:39:33,160 the captain believes the autopilot has disengaged... 731 00:39:34,680 --> 00:39:35,840 I have control. 732 00:39:36,560 --> 00:39:37,680 ..when it hasn't. 733 00:39:37,720 --> 00:39:39,360 (ALARM GOING OFF) 734 00:39:40,560 --> 00:39:41,760 The autopilot remained engaged 735 00:39:41,800 --> 00:39:43,200 and they didn't realise that was the case, 736 00:39:43,240 --> 00:39:45,440 so effectively from that point until it disengaged, 737 00:39:45,480 --> 00:39:47,160 they were fighting the autopilot. 738 00:39:47,200 --> 00:39:49,960 They wanted to climb. It wanted to descend. 739 00:39:50,000 --> 00:39:51,880 And because of the way the flight controls were configured, 740 00:39:51,920 --> 00:39:53,360 the autopilot was going to win. 741 00:39:54,880 --> 00:39:57,640 Engaged in a tug of war with the aircraft, 742 00:39:57,680 --> 00:39:59,680 cognitive tunnelling takes over. 743 00:39:59,720 --> 00:40:00,720 (ALARM GOING OFF) 744 00:40:00,760 --> 00:40:03,840 Something's wrong. I can't get the plane to climb. 745 00:40:03,880 --> 00:40:05,040 How's your side? 746 00:40:05,720 --> 00:40:08,880 The highly stressed pilots don't register the audible warnings 747 00:40:08,920 --> 00:40:11,640 telling them that the autopilot is still engaged. 748 00:40:12,120 --> 00:40:13,440 It's really heavy. 749 00:40:14,680 --> 00:40:16,120 The trim's not doing anything either. 750 00:40:17,720 --> 00:40:21,120 The final blow is a one-of-a-kind autopilot system 751 00:40:21,160 --> 00:40:23,200 without a force override. 752 00:40:24,080 --> 00:40:26,400 I have every sympathy for crews being startled 753 00:40:26,440 --> 00:40:27,680 when something unusual happens, 754 00:40:27,720 --> 00:40:29,440 whether there's an explosive engine failure, 755 00:40:29,480 --> 00:40:31,000 or a lightning strike in this case. 756 00:40:31,680 --> 00:40:34,040 But the training must kick in 757 00:40:34,080 --> 00:40:37,800 and the crew must revert to, in effect, as I say, 758 00:40:37,840 --> 00:40:39,600 "Sit on your hands for a few moments, 759 00:40:39,640 --> 00:40:42,160 "make an assessment of what's happened, 760 00:40:42,200 --> 00:40:45,840 "what's gone wrong, what's working, what's not working 761 00:40:45,880 --> 00:40:47,480 "and then deal with the situation from there." 762 00:40:49,080 --> 00:40:51,600 Oh, no! Come on! 763 00:40:51,640 --> 00:40:52,640 We're dropping! 764 00:40:56,840 --> 00:41:01,320 If it wasn't for a split-second fluke error in the computer system 765 00:41:01,360 --> 00:41:03,600 and the relentless efforts of the crew... 766 00:41:03,640 --> 00:41:05,480 Speed. Speed! 767 00:41:06,280 --> 00:41:09,360 ..Flight 67-80 would have slammed into the North Sea 768 00:41:09,400 --> 00:41:11,720 at 380 miles per hour. 769 00:41:17,800 --> 00:41:20,040 I would say I was a nervous flier for a couple years. 770 00:41:20,800 --> 00:41:22,320 So, I've just kind of gone through the motions 771 00:41:22,360 --> 00:41:26,000 of sort of, building myself up to knowing that it's gonna be fine. 772 00:41:30,680 --> 00:41:33,680 The final report recommends several safety changes 773 00:41:33,720 --> 00:41:35,680 to the autopilot system. 774 00:41:35,720 --> 00:41:37,040 We then made recommendations 775 00:41:37,080 --> 00:41:40,320 looking at how aircraft could be certified in future 776 00:41:40,360 --> 00:41:43,600 to make sure that no future design could be certified 777 00:41:43,640 --> 00:41:47,240 where neither operation of the control column, 778 00:41:47,280 --> 00:41:50,560 nor operation of the pitch control switches 779 00:41:50,600 --> 00:41:52,680 would result in disconnection of the autopilot. 780 00:41:54,160 --> 00:41:55,480 For investigators, 781 00:41:55,520 --> 00:42:00,320 the lessons of Loganair 67-80 go beyond this one near-tragedy. 782 00:42:05,120 --> 00:42:08,240 We can only go so far in educating human operators 783 00:42:08,280 --> 00:42:09,920 in how a system works. 784 00:42:09,960 --> 00:42:13,520 Ultimately, we have to recognise that they will behave instinctively, 785 00:42:13,560 --> 00:42:15,360 particularly when under stress. 786 00:42:15,400 --> 00:42:18,160 That's the real challenge for the future of automated systems. 787 00:42:18,200 --> 00:42:21,200 Captioned by Ai-Media ai-media.tv