1 00:00:01,455 --> 00:00:03,915 Above the remote Alaskan wilderness, 2 00:00:06,615 --> 00:00:10,607 two planes collide. Mayday. 3 00:00:10,671 --> 00:00:14,115 Mayday. A witness races to help. 4 00:00:14,935 --> 00:00:17,759 All I saw was a whole bunch of people 5 00:00:17,887 --> 00:00:21,015 floating. Six people are dead. 6 00:00:21,175 --> 00:00:23,135 The mid air collision is probably the most 7 00:00:23,175 --> 00:00:24,915 scary thing that could happen to you. 8 00:00:25,375 --> 00:00:28,199 NTSB investigators talked to the surviving 9 00:00:28,247 --> 00:00:31,527 pilot. Look, he was just there. I couldn't 10 00:00:31,551 --> 00:00:34,319 avoid him. When they examined the Onard 11 00:00:34,367 --> 00:00:37,071 alerting system, why didn't he turn away? 12 00:00:37,263 --> 00:00:39,999 The mystery deepens. We're missing 13 00:00:40,087 --> 00:00:42,863 something. But then investigators get an 14 00:00:42,879 --> 00:00:45,543 unexpected glimpse. Whoa. Into a key 15 00:00:45,599 --> 00:00:47,751 moment in time. It was eerie and 16 00:00:47,783 --> 00:00:50,287 disturbing to see the photos because they 17 00:00:50,311 --> 00:00:52,755 were taken in a person's last moments. 18 00:01:18,925 --> 00:01:22,141 It's a busy day at Alaska's misty fjords 19 00:01:22,213 --> 00:01:25,805 Floatplane base. Four cruise 20 00:01:25,845 --> 00:01:27,797 ship passengers have booked a sightseeing 21 00:01:27,861 --> 00:01:30,469 flight over Alaska's spectacular Southeast 22 00:01:30,517 --> 00:01:34,501 co coast. Okay folks, get comfortable 23 00:01:34,533 --> 00:01:35,865 and fasten your seat belts. 24 00:01:38,205 --> 00:01:41,165 46 year old Randy Sullivan is the owner of 25 00:01:41,205 --> 00:01:44,145 Mountain Air Services and its only pilot. 26 00:01:45,565 --> 00:01:47,237 Hey, looks like you're gonna have the best 27 00:01:47,261 --> 00:01:50,645 view in Alaska. You can hardly wait. This 28 00:01:50,685 --> 00:01:52,557 will be Sullivan's second flight of the 29 00:01:52,581 --> 00:01:56,013 day. Just got a 30 00:01:56,029 --> 00:01:57,785 few things to do before we get started. 31 00:01:58,745 --> 00:02:00,745 Randy Sullivan has spent most of his 32 00:02:00,785 --> 00:02:02,965 career flying over misty fjords. 33 00:02:06,625 --> 00:02:09,449 Sponder on and broadcasting. Okay, guys, 34 00:02:09,497 --> 00:02:10,725 put your headsets on. 35 00:02:14,065 --> 00:02:17,725 Mountain Air was a small operator doing 36 00:02:18,185 --> 00:02:21,449 primarily sightseeing. TR reps. Can you 37 00:02:21,457 --> 00:02:24,545 guys hear me? Okay. Okay, here we go. 38 00:02:25,525 --> 00:02:27,197 This would have been his entire life 39 00:02:27,261 --> 00:02:29,341 running this company and he would have 40 00:02:29,373 --> 00:02:30,625 loved what he was doing. 41 00:02:32,965 --> 00:02:35,941 All right, flight controls free and 42 00:02:35,973 --> 00:02:39,105 correct. Master fuel check. 43 00:02:39,605 --> 00:02:43,189 Landing light's check. Just after 44 00:02:43,237 --> 00:02:45,725 12 noon, the mountain Air float plane is 45 00:02:45,765 --> 00:02:46,945 ready for takeoff. 46 00:02:51,195 --> 00:02:52,811 Okay, that's five minutes since last 47 00:02:52,883 --> 00:02:56,291 departure. Pilots space out their 48 00:02:56,323 --> 00:02:58,235 takeoffs since there's no air traffic 49 00:02:58,315 --> 00:02:59,655 control in this area. 50 00:03:01,955 --> 00:03:04,299 Missy traffic, this is Beaver Five two 51 00:03:04,347 --> 00:03:06,147 Delta Bravo ready for a straight out. Any 52 00:03:06,171 --> 00:03:09,947 conflicting misty traffic. Sullivan radios 53 00:03:10,011 --> 00:03:11,615 other pilots in the area. 54 00:03:13,635 --> 00:03:16,343 In airspace like the misty fjords, the 55 00:03:16,359 --> 00:03:19,635 pilots all control themselves and it's 56 00:03:20,015 --> 00:03:23,275 primarily a C and B SC situation. 57 00:03:23,895 --> 00:03:25,967 Without any air traffic control to keep 58 00:03:25,991 --> 00:03:27,655 you separated, you have to maintain that 59 00:03:27,695 --> 00:03:28,955 separation yourself. 60 00:03:37,775 --> 00:03:40,635 It's a textbook takeoff in light winds. 61 00:03:42,795 --> 00:03:44,779 Today's 40 mile flight will take 62 00:03:44,827 --> 00:03:47,615 passengers from Rudyard Bay to Ketchikan. 63 00:03:49,115 --> 00:03:51,579 They'll cross high mountains and dramatic 64 00:03:51,627 --> 00:03:54,443 terrain. Misty fjords is an absolutely 65 00:03:54,499 --> 00:03:56,979 beautiful area. It's towering mountains, 66 00:03:57,067 --> 00:04:00,091 glaciers, lakes, fjords, wildlife. 67 00:04:00,243 --> 00:04:01,787 And the best way to see a place like that, 68 00:04:01,811 --> 00:04:03,219 of course, is from an airplane where you 69 00:04:03,227 --> 00:04:06,435 can get the full impact of the scenery and 70 00:04:06,475 --> 00:04:08,255 the immenseness of the area. 71 00:04:11,705 --> 00:04:14,793 Every year more than 100,000 cruise ship 72 00:04:14,849 --> 00:04:17,325 passengers visit Alaska's misty fjords. 73 00:04:18,585 --> 00:04:20,841 The flight tours have become an essential 74 00:04:20,953 --> 00:04:22,697 experience for those who can afford the 75 00:04:22,721 --> 00:04:24,085 luxury price tag. 76 00:04:27,265 --> 00:04:28,969 If you look out to your left, you'll see 77 00:04:29,017 --> 00:04:30,665 cliffs that were carved smooth by the last 78 00:04:30,705 --> 00:04:34,489 grade ice age. Randy Sullivan points 79 00:04:34,537 --> 00:04:36,725 out the highlights throughout the flight 80 00:04:39,505 --> 00:04:41,217 being a single pilot operation. While 81 00:04:41,241 --> 00:04:43,401 you're doing the tours, you're 82 00:04:43,433 --> 00:04:45,273 multitasking with your customers all the 83 00:04:45,289 --> 00:04:47,345 time, trying to give them the best tour 84 00:04:47,385 --> 00:04:49,321 that you can give them. At the same time, 85 00:04:49,353 --> 00:04:51,801 you're also multitasking as a pilot where 86 00:04:51,833 --> 00:04:53,849 you're trying to maintain your situational 87 00:04:53,897 --> 00:04:56,097 awareness of all the other aircraft as 88 00:04:56,121 --> 00:04:57,977 well as you're a lot of times flying at 89 00:04:58,001 --> 00:05:00,481 very low level through the terrain, which 90 00:05:00,513 --> 00:05:02,345 adds one more bit of complexity to the 91 00:05:02,385 --> 00:05:06,149 entire operation. Mountain Air Services 92 00:05:06,237 --> 00:05:09,221 operates a de Havilland Beaver, a single 93 00:05:09,253 --> 00:05:10,665 engine prop plane. 94 00:05:13,605 --> 00:05:15,501 The Beaver was originally built for the 95 00:05:15,533 --> 00:05:18,145 United States air Force in 1951, 96 00:05:19,045 --> 00:05:21,613 but many are now operated by northern bush 97 00:05:21,669 --> 00:05:24,757 pilots. The Hapland Beaver was a uniquely 98 00:05:24,821 --> 00:05:27,781 designed airplane and the takeoff and 99 00:05:27,813 --> 00:05:30,517 landing is absolutely incredible. That's 100 00:05:30,541 --> 00:05:32,517 what makes it so versatile in the bush is 101 00:05:32,541 --> 00:05:34,157 that you can get it in and out of pretty 102 00:05:34,181 --> 00:05:36,381 much any little lake. If you're on wheels 103 00:05:36,413 --> 00:05:38,765 or skis, you can get it off short strips 104 00:05:38,845 --> 00:05:40,585 or short frozen lakes. 105 00:05:43,725 --> 00:05:46,301 Misty traffic. Beaver 2 Delta Bravo 106 00:05:46,373 --> 00:05:49,325 exiting Rudyard, climbing through 1900 107 00:05:49,365 --> 00:05:53,013 westbound. Check that 45 mike. Mike is 108 00:05:53,069 --> 00:05:54,861 just off the water now and well behind 109 00:05:54,893 --> 00:05:55,465 you. 110 00:05:58,545 --> 00:06:01,281 It's May, and this part of Alaska is 111 00:06:01,313 --> 00:06:04,977 enjoying exceptionally good weather. On 112 00:06:05,001 --> 00:06:06,673 the Alaska coast, the weather can change 113 00:06:06,769 --> 00:06:09,593 extremely rapidly. It can go from a 114 00:06:09,609 --> 00:06:11,753 beautiful clear day to just horrible 115 00:06:11,809 --> 00:06:14,601 weather within a very short period of 116 00:06:14,633 --> 00:06:17,769 time. When the days are good, all the 117 00:06:17,777 --> 00:06:20,409 aircraft are flying, everybody is out 118 00:06:20,457 --> 00:06:23,033 making haywell the sun shines. Have a good 119 00:06:23,049 --> 00:06:24,885 cruise so far it's been great. 120 00:06:26,425 --> 00:06:28,801 The forecast for tomorrow is low clouds 121 00:06:28,833 --> 00:06:32,625 and rain. So today Sullivan plans to 122 00:06:32,665 --> 00:06:35,833 operate a full day of flights. You all are 123 00:06:35,849 --> 00:06:37,753 pretty lucky. They called this place the 124 00:06:37,769 --> 00:06:40,801 Misty Fjord for a reason. Whetherather 125 00:06:40,833 --> 00:06:42,045 like this is pretty rare. 126 00:06:45,425 --> 00:06:48,951 Beaver 8 Golf Mike is 2700ft in the climb 127 00:06:49,073 --> 00:06:51,563 exiting the bay. We've got the mountain 128 00:06:51,579 --> 00:06:54,355 air Beaver ahead. We will fall inrail 129 00:06:54,435 --> 00:06:57,395 behind. Hey, Dave, I've got you on 130 00:06:57,435 --> 00:06:59,587 display, but I don't have you visual. As 131 00:06:59,611 --> 00:07:01,907 long as you can see me, we're good. I got 132 00:07:01,931 --> 00:07:03,891 you above and ahead of me, Randy. Enjoy 133 00:07:03,923 --> 00:07:04,615 the ride. 134 00:07:06,755 --> 00:07:10,075 Oh. Even if we can't see each other, the 135 00:07:10,115 --> 00:07:11,203 display lets us know where the other 136 00:07:11,219 --> 00:07:14,515 planes are. Cool. The traffic systems will 137 00:07:14,555 --> 00:07:16,531 enhance your ability for the SE&AV void 138 00:07:16,603 --> 00:07:19,341 because it will alert you of aircraft that 139 00:07:19,373 --> 00:07:21,597 you may have missed because of visibility 140 00:07:21,701 --> 00:07:23,825 issues. For you get too close. 141 00:07:25,685 --> 00:07:27,237 Coming up in about two minutes on your 142 00:07:27,261 --> 00:07:28,885 right, you're going to see one of the 143 00:07:28,925 --> 00:07:30,685 highlights of the trip, the majestic 144 00:07:30,725 --> 00:07:31,905 Mahoney Falls. 145 00:07:34,725 --> 00:07:37,485 Twenty minutes into the flight, the beaver 146 00:07:37,565 --> 00:07:38,985 approaches the waterfall. 147 00:07:43,265 --> 00:07:45,537 Passengers are treated to a spectacular 148 00:07:45,601 --> 00:07:46,205 view. 149 00:07:55,025 --> 00:07:57,685 The beaver and another aircraft collide. 150 00:07:58,825 --> 00:08:02,153 The beaver basically came apart. It fel 151 00:08:02,209 --> 00:08:04,285 3,000ft from the sky. 152 00:08:06,345 --> 00:08:09,073 A retired fisherman on George Inlet is 153 00:08:09,129 --> 00:08:10,605 shocked by what he sees. 154 00:08:14,185 --> 00:08:16,665 Meday. Meday. This is Hotel SE calling 155 00:08:16,705 --> 00:08:17,845 Coast Guard radio. 156 00:08:20,425 --> 00:08:22,217 Go ahead, state the nature of your 157 00:08:22,241 --> 00:08:23,005 emergency. 158 00:08:26,105 --> 00:08:28,793 The second plane involved is a larger 10 159 00:08:28,849 --> 00:08:31,625 passenger de Havilland Otter. Two float 160 00:08:31,665 --> 00:08:33,805 planes down George Inlet. 161 00:08:38,845 --> 00:08:42,357 The Otter was still largely intact. There 162 00:08:42,381 --> 00:08:45,973 was damage. The pilot obviously 163 00:08:46,149 --> 00:08:49,509 kept his cool and managed to control the 164 00:08:49,517 --> 00:08:53,061 aircraft. I saw 165 00:08:53,253 --> 00:08:56,077 an otter float planane crash into the 166 00:08:56,101 --> 00:08:59,445 water with a huge splash. And they got 167 00:08:59,485 --> 00:09:02,353 closer and all I saw was a whole bunch of 168 00:09:02,469 --> 00:09:07,468 people floating in an area 50, 169 00:09:07,549 --> 00:09:11,057 60 yards. But there was one person 170 00:09:11,241 --> 00:09:12,925 ever made it out of the airplane. 171 00:09:14,505 --> 00:09:17,153 The 10 survivors, including the pilot, 172 00:09:17,249 --> 00:09:20,985 are rushed to hospital. There are no 173 00:09:21,025 --> 00:09:23,281 survivors from the plane piloted by Randy 174 00:09:23,313 --> 00:09:24,085 Sullivan. 175 00:09:27,065 --> 00:09:29,169 How could two planes in one of the most 176 00:09:29,217 --> 00:09:31,585 popular tourist destinations on earth 177 00:09:31,745 --> 00:09:33,285 collide in midair? 178 00:09:40,665 --> 00:09:43,065 Within hours, the National Transportation 179 00:09:43,145 --> 00:09:46,505 Safety Board, or ntsb, dispatches a team 180 00:09:46,545 --> 00:09:49,085 of investigators to search for wreckage. 181 00:09:52,105 --> 00:09:54,793 We still have to recover the planes, and 182 00:09:54,809 --> 00:09:56,537 then we have to look at those. And it 183 00:09:56,561 --> 00:09:58,265 takes some significant work to really 184 00:09:58,345 --> 00:09:59,793 understand how the two came together. But 185 00:09:59,809 --> 00:10:02,033 we have some great experts at the NTSB who 186 00:10:02,049 --> 00:10:06,181 are well versed in that. Aaron Sauer 187 00:10:06,253 --> 00:10:08,225 is named lead investigator. 188 00:10:09,605 --> 00:10:11,949 The wreckage area of the Beaver was 189 00:10:11,997 --> 00:10:15,093 scattered for about 3,000ft. A portion of 190 00:10:15,109 --> 00:10:17,653 the main fuselage was located upside down 191 00:10:17,709 --> 00:10:19,917 in the saltwater. There was a lot of 192 00:10:19,941 --> 00:10:22,821 debris that was mixed into the terrain. 193 00:10:22,893 --> 00:10:25,109 And that mountainous area vegetation was 194 00:10:25,157 --> 00:10:28,433 high. It was very difficult to navigate to 195 00:10:28,449 --> 00:10:31,137 try and recover as much of the debris from 196 00:10:31,161 --> 00:10:34,737 the Beaver that we could. The other 197 00:10:34,761 --> 00:10:37,097 aircraft, the Otter, is owned by the 198 00:10:37,121 --> 00:10:39,793 largest tour operator in the area, Taquan 199 00:10:39,849 --> 00:10:43,085 Air. It sank in 80ft of water. 200 00:10:43,425 --> 00:10:45,485 The floor of the Otter were separated. 201 00:10:45,785 --> 00:10:49,057 They ended up washing ashore. But 202 00:10:49,081 --> 00:10:51,025 ultimately they were able to get divers 203 00:10:51,065 --> 00:10:52,665 down, locate the wreckage almost 204 00:10:52,705 --> 00:10:54,853 immediately, and they were able to 205 00:10:54,909 --> 00:10:56,645 successfully get that aircraft up on that 206 00:10:56,685 --> 00:10:57,345 barge. 207 00:11:06,005 --> 00:11:07,789 Tag the beaver wreckage, and when the 208 00:11:07,797 --> 00:11:09,825 otter comes, we're goingna put it there. 209 00:11:11,325 --> 00:11:13,709 The small sightseeing planes were not 210 00:11:13,757 --> 00:11:16,413 required to carry black boxes. Keep an eye 211 00:11:16,429 --> 00:11:18,557 out for avionics, cameras, phones, 212 00:11:18,621 --> 00:11:21,503 anything with photos or s data that will 213 00:11:21,519 --> 00:11:24,303 help us piece this together. Without 214 00:11:24,399 --> 00:11:26,519 recorders, the investigation becomes much 215 00:11:26,567 --> 00:11:29,671 more difficult. So without the cockpit 216 00:11:29,703 --> 00:11:31,735 Voice recorder and flight data recorder. 217 00:11:31,895 --> 00:11:33,915 We had to look for other sources of data. 218 00:11:34,655 --> 00:11:36,035 Hey, let me move this. 219 00:11:40,135 --> 00:11:42,791 As the team surveys the Beaver wreckage, 220 00:11:42,943 --> 00:11:44,839 they find evidence that can help them 221 00:11:44,887 --> 00:11:46,875 piece together the violent collision. 222 00:11:47,965 --> 00:11:51,693 These are sawtooth marks from a propeller 223 00:11:51,829 --> 00:11:54,105 striking the right wing. 224 00:11:55,365 --> 00:11:57,901 We wanted to understand what angle did we 225 00:11:57,933 --> 00:12:01,309 have. That was very important for us to 226 00:12:01,397 --> 00:12:04,773 understand in order to recreate the 227 00:12:04,789 --> 00:12:08,225 collision and aid us in the investigation. 228 00:12:09,925 --> 00:12:11,865 The patterns in the inboard direction. 229 00:12:13,745 --> 00:12:15,817 So the otter came from behind and to the 230 00:12:15,841 --> 00:12:19,441 right. The discovery begins to 231 00:12:19,473 --> 00:12:21,801 unveil what happened in the skies over 232 00:12:21,833 --> 00:12:25,625 Misty Fjord. The collision angle was 233 00:12:25,665 --> 00:12:28,017 important for us because what it told us 234 00:12:28,041 --> 00:12:30,233 is both airplanes weren't necessarily on a 235 00:12:30,249 --> 00:12:32,809 head on collision course. They were more 236 00:12:32,817 --> 00:12:35,905 or less headed to the same location with a 237 00:12:35,945 --> 00:12:39,509 shallow degree of angle. The collision was 238 00:12:39,557 --> 00:12:42,989 more of a sideswipe. Both planes 239 00:12:43,037 --> 00:12:46,861 took off from Rudyard Bay here and 240 00:12:46,893 --> 00:12:50,065 headed to the cruise ship in Ketchikin. 241 00:12:51,245 --> 00:12:55,357 The Beaver left first and 242 00:12:55,381 --> 00:12:57,865 a few minutes later the Otter departed. 243 00:12:59,245 --> 00:13:01,645 With a basic understanding of how the two 244 00:13:01,685 --> 00:13:04,261 planes collided, investigators try to 245 00:13:04,293 --> 00:13:06,625 pinpoint where the accident occurred. 246 00:13:08,315 --> 00:13:14,987 We had one witness who 247 00:13:15,011 --> 00:13:17,535 was located here. 248 00:13:18,635 --> 00:13:21,443 We had a witness that was hunting in the 249 00:13:21,499 --> 00:13:24,203 area that didn't see the collision but 250 00:13:24,259 --> 00:13:27,107 heard the collision. Which then in turn 251 00:13:27,171 --> 00:13:30,339 gave us an idea of where exactly did this 252 00:13:30,427 --> 00:13:34,017 happen. Up in a point in sky. Based on 253 00:13:34,041 --> 00:13:36,245 his account, the collision happened 254 00:13:37,225 --> 00:13:38,525 somewhere in here. 255 00:13:40,625 --> 00:13:42,921 Investigators now know exactly where the 256 00:13:42,953 --> 00:13:45,265 accident occurred, but they still don't 257 00:13:45,305 --> 00:13:49,057 know why. Maybe they 258 00:13:49,081 --> 00:13:52,165 were converging on this point. 259 00:13:52,905 --> 00:13:55,369 The planes collided very near the scenic 260 00:13:55,417 --> 00:13:59,525 Mahoney Falls. It is certainly possible 261 00:14:00,955 --> 00:14:02,615 it has happened before. 262 00:14:03,875 --> 00:14:06,251 A similar mid air collision happened over 263 00:14:06,283 --> 00:14:08,375 Arizona in 1986. 264 00:14:09,795 --> 00:14:12,475 A Twin Otter and a helicopter collided 265 00:14:12,555 --> 00:14:15,735 over the Grand Canyon, killing 25 people. 266 00:14:16,515 --> 00:14:18,771 Both aircraft were also approaching a 267 00:14:18,803 --> 00:14:21,715 popular scenic attraction. Air tour 268 00:14:21,755 --> 00:14:23,843 flights have a higher rate of mid air 269 00:14:23,859 --> 00:14:25,355 collision, statistically speaking, 270 00:14:25,435 --> 00:14:27,989 because they operate in areas with dense 271 00:14:28,037 --> 00:14:30,797 traffic around various scenic landmarks. 272 00:14:30,981 --> 00:14:34,021 And in addition, they operate without air 273 00:14:34,053 --> 00:14:35,905 traffic control separation. 274 00:14:39,045 --> 00:14:42,357 What was the weather like that day? I'll 275 00:14:42,381 --> 00:14:46,133 check it out. Did Alaska's 276 00:14:46,189 --> 00:14:48,613 rapidly changing weather play a role in 277 00:14:48,629 --> 00:14:51,805 the accident? So weather conditions in any 278 00:14:51,845 --> 00:14:54,669 accident are important to understand the 279 00:14:54,717 --> 00:14:56,109 environment that these pilots are 280 00:14:56,157 --> 00:14:58,335 operating in. Are the weather conditions 281 00:14:58,495 --> 00:15:00,959 cloudy? Does that limit their ability to 282 00:15:01,007 --> 00:15:03,783 see? Does it limit their ability to react 283 00:15:03,839 --> 00:15:05,835 to certain situations? 284 00:15:07,575 --> 00:15:09,767 These are from a weather cab eight miles 285 00:15:09,791 --> 00:15:13,295 from the accident. Investigators review 286 00:15:13,335 --> 00:15:15,863 weather reports for nearby George Inlet at 287 00:15:15,879 --> 00:15:18,911 the time of the accident. A few scattered 288 00:15:18,983 --> 00:15:22,503 clouds, but much higher than they 289 00:15:22,519 --> 00:15:26,137 were flying. The weather conditions 290 00:15:26,201 --> 00:15:28,665 in Ketchikan on the day of the accident 291 00:15:28,745 --> 00:15:31,041 were beautiful. So at that Point we knew 292 00:15:31,073 --> 00:15:32,921 that the conditions were not going to be a 293 00:15:32,953 --> 00:15:35,809 factor in this accident. Something else 294 00:15:35,857 --> 00:15:37,329 prevented these guys from seeing each 295 00:15:37,377 --> 00:15:37,965 other. 296 00:15:49,405 --> 00:15:53,877 What if the 297 00:15:53,901 --> 00:15:57,221 pilots didn't have enough time to look out 298 00:15:57,253 --> 00:15:58,745 the window for other traffic? 299 00:16:00,325 --> 00:16:02,693 Or maybe the pilots were trying to give 300 00:16:02,709 --> 00:16:04,145 their customers the best view. 301 00:16:05,885 --> 00:16:08,349 What prevented the pilots from seeing each 302 00:16:08,397 --> 00:16:10,445 other as they converged on the scenic 303 00:16:10,485 --> 00:16:13,373 waterfall? Flying an aircraft full of 304 00:16:13,389 --> 00:16:16,289 tourists can be a very challenging task. 305 00:16:16,457 --> 00:16:18,825 You have a number of people that all want 306 00:16:18,945 --> 00:16:20,985 to ask questions. They all want to see 307 00:16:21,025 --> 00:16:23,353 different things. Especially in an area 308 00:16:23,369 --> 00:16:25,057 like the Misty fjords where there is so 309 00:16:25,081 --> 00:16:28,401 much to see. It is a lot for a pilot to do 310 00:16:28,433 --> 00:16:31,761 all the same time. Well, the local 311 00:16:31,833 --> 00:16:35,161 pilots certainly were concerned enough to 312 00:16:35,193 --> 00:16:36,085 create this. 313 00:16:38,825 --> 00:16:41,433 Investigators discover a set of guidelines 314 00:16:41,569 --> 00:16:44,413 agreed upon by tour operators to enhance 315 00:16:44,469 --> 00:16:47,421 safety over my fjords. The letter of 316 00:16:47,453 --> 00:16:49,509 agreement between the operators was 317 00:16:49,597 --> 00:16:52,125 intended to help them coordinate their 318 00:16:52,165 --> 00:16:54,453 routes of flight and their call outs so 319 00:16:54,469 --> 00:16:56,605 that they could become better aware of 320 00:16:56,765 --> 00:16:58,997 where they would each be operating and 321 00:16:59,021 --> 00:17:02,013 avoid each other. The companies were aware 322 00:17:02,109 --> 00:17:04,229 of this hazard of the mid air collisions 323 00:17:04,317 --> 00:17:06,285 and that they were attempting to implement 324 00:17:06,365 --> 00:17:09,381 some procedural mitigations against this 325 00:17:09,413 --> 00:17:10,145 hazard. 326 00:17:12,725 --> 00:17:15,749 It looks like most aircraft flying tours 327 00:17:15,837 --> 00:17:19,301 also had on board an ADSB traffic warning 328 00:17:19,373 --> 00:17:19,985 system. 329 00:17:21,805 --> 00:17:25,317 ADSB, or Automatic Dependent Surveillance 330 00:17:25,381 --> 00:17:28,013 Broadcast is a traffic alerting system 331 00:17:28,109 --> 00:17:30,957 that transmits a plane's GPS location and 332 00:17:30,981 --> 00:17:33,317 altitude to ground stations and other 333 00:17:33,341 --> 00:17:36,365 aircraft. If two airplanes get too close 334 00:17:36,405 --> 00:17:39,003 to each other, an alert is issued in both 335 00:17:39,059 --> 00:17:40,907 cockpits. When your traffic system tells 336 00:17:40,931 --> 00:17:43,139 you you've got a conflict, it's going to 337 00:17:43,147 --> 00:17:44,955 have your attention immediately. It will 338 00:17:44,995 --> 00:17:46,403 only tell you that there's a problem when 339 00:17:46,419 --> 00:17:49,987 there is. It looks like the Otter had 340 00:17:50,011 --> 00:17:52,095 an alerting system installed on board. 341 00:17:52,395 --> 00:17:55,659 What about the Beaver? Yep, it had a 342 00:17:55,707 --> 00:17:57,615 system installed on it as well. 343 00:17:59,035 --> 00:18:00,923 It was important for us to understand 344 00:18:01,059 --> 00:18:04,469 which aircraft had which equipment 345 00:18:04,557 --> 00:18:06,973 as far as alerting capability, traffic 346 00:18:07,029 --> 00:18:11,185 displays. Okay, here's the Otter system. 347 00:18:12,125 --> 00:18:14,197 Investigators first examine the Otter, 348 00:18:14,301 --> 00:18:16,165 the aircraft that collided with the 349 00:18:16,205 --> 00:18:17,785 smaller plane to its left. 350 00:18:19,445 --> 00:18:23,013 The Otter uses GPS and a radio transponder 351 00:18:23,069 --> 00:18:26,517 to broadcast its altitude and position. A 352 00:18:26,541 --> 00:18:28,965 color screen inside the cockpit plots 353 00:18:29,045 --> 00:18:31,585 other nearby aircraft on a moving map. 354 00:18:32,165 --> 00:18:34,493 Where does s the Beaver have? Well, the 355 00:18:34,509 --> 00:18:37,157 Beaver pilot had a different system. It 356 00:18:37,181 --> 00:18:39,465 had a tablet to display traffic info. 357 00:18:41,645 --> 00:18:43,765 So we knew that both aircraft were 358 00:18:43,845 --> 00:18:45,421 equipped with some level of traffic 359 00:18:45,453 --> 00:18:47,741 display. So the question was, were they 360 00:18:47,773 --> 00:18:49,745 able to function as designed? 361 00:19:00,065 --> 00:19:03,729 Let, let's see what we got. Investigators 362 00:19:03,817 --> 00:19:06,041 review whether ground stations received 363 00:19:06,113 --> 00:19:08,721 any GPS transmissions from the aircraft 364 00:19:08,873 --> 00:19:11,553 detailing their locations. There's the 365 00:19:11,569 --> 00:19:12,245 Beaver. 366 00:19:14,665 --> 00:19:17,241 Misty traffic. Beaver 2 Delta Bravo 367 00:19:17,313 --> 00:19:20,265 exiting Rudyard climbing through 1900 368 00:19:20,305 --> 00:19:21,125 westbound. 369 00:19:23,965 --> 00:19:27,901 And there's the otter. All right folks, 370 00:19:27,933 --> 00:19:29,509 if you look outside your windows down at 371 00:19:29,517 --> 00:19:30,821 the hills below, you might just see some 372 00:19:30,853 --> 00:19:31,625 wildlife. 373 00:19:36,845 --> 00:19:38,485 Both airplanes were broadcasting their 374 00:19:38,525 --> 00:19:40,061 position but they still hit each other. 375 00:19:40,173 --> 00:19:41,305 Doesn't make sense. 376 00:19:43,845 --> 00:19:45,825 Maybe the system didn't issue an alert. 377 00:19:47,565 --> 00:19:49,145 The outter pilot would know. 378 00:19:51,385 --> 00:19:53,513 Seems like so many of these investigations 379 00:19:53,609 --> 00:19:56,169 when you have midairr are just not 380 00:19:56,217 --> 00:19:59,753 survivable. And so it. It was 381 00:19:59,809 --> 00:20:02,401 very fortunate to be able to talk to the 382 00:20:02,433 --> 00:20:03,125 pilot. 383 00:20:07,945 --> 00:20:09,285 Tell me about the flight. 384 00:20:10,465 --> 00:20:12,857 Investigators interview the otter pilot 385 00:20:12,961 --> 00:20:15,457 Lou Beck, who has just been released from 386 00:20:15,521 --> 00:20:18,605 hospital. Passengers were happy. 387 00:20:19,025 --> 00:20:22,561 Air was smooth. Was it 388 00:20:22,713 --> 00:20:23,925 busy out there? 389 00:20:25,905 --> 00:20:28,165 Visually? I never saw anyone else. 390 00:20:29,225 --> 00:20:32,193 What about the traffic alerting system it 391 00:20:32,209 --> 00:20:35,125 was on. I saw targets on the screen but 392 00:20:35,505 --> 00:20:37,205 they were well south of me. 393 00:20:39,985 --> 00:20:43,373 Hey, got one. Three miles out, 394 00:20:43,549 --> 00:20:46,865 three o'clock. Opposite direction. 395 00:20:47,845 --> 00:20:48,985 No conflicts. 396 00:20:51,325 --> 00:20:53,757 I flew a longer route than the other 397 00:20:53,781 --> 00:20:56,069 planes. Took me away from most of the 398 00:20:56,077 --> 00:20:59,053 regular traffic. But you still ended up at 399 00:20:59,069 --> 00:21:01,581 the waterfall. I did. That's when all hell 400 00:21:01,613 --> 00:21:04,997 broke looseke. Ok, hey folks, 401 00:21:05,181 --> 00:21:07,349 in a few seconds we're going to arrive at 402 00:21:07,357 --> 00:21:11,455 the beautiful F. He was just there. 403 00:21:11,495 --> 00:21:14,555 I couldn't avoid him. Hang on everyone. 404 00:21:17,975 --> 00:21:19,727 Was there any alert from the traffic 405 00:21:19,791 --> 00:21:22,967 system? Nothing after the impact. I just 406 00:21:23,111 --> 00:21:26,835 went into survival mode. Brace for impact. 407 00:21:27,535 --> 00:21:28,875 Brace, brace, brace. 408 00:21:38,755 --> 00:21:42,011 The pilot seemed very attentive to midair 409 00:21:42,043 --> 00:21:44,859 collisions as a hazard. He was aware of 410 00:21:44,907 --> 00:21:46,851 the cockpit display of traffic information 411 00:21:46,923 --> 00:21:50,107 in the cockpit and he recalled looking at 412 00:21:50,131 --> 00:21:52,483 it to scan for traffic before the 413 00:21:52,499 --> 00:21:54,779 collision. Look, I just want to reiterate 414 00:21:54,827 --> 00:21:57,843 that the alert system did not sound an 415 00:21:57,859 --> 00:22:00,695 alert. Thank you. 416 00:22:01,635 --> 00:22:03,055 This was very helpful. 417 00:22:05,495 --> 00:22:07,471 Investigators are now confident the 418 00:22:07,503 --> 00:22:09,647 collision happened without a warning to 419 00:22:09,671 --> 00:22:11,235 alert the otterilot. 420 00:22:12,575 --> 00:22:16,075 The question is why? Hang on everyone. 421 00:22:21,415 --> 00:22:23,079 Let's have a look at the otters traffic Al 422 00:22:23,087 --> 00:22:26,519 learning system investigators use 423 00:22:26,567 --> 00:22:29,151 the ground station data to recreate what 424 00:22:29,183 --> 00:22:30,935 the otopilot would have seen on his 425 00:22:30,975 --> 00:22:33,371 traffic alerting system moments before 426 00:22:33,443 --> 00:22:37,075 crashing into the beaver. It's painting 427 00:22:37,115 --> 00:22:40,215 targets. There's the beaver approaching. 428 00:22:40,795 --> 00:22:43,135 The alert should happen any second now. 429 00:22:43,955 --> 00:22:46,283 As the beaver gets within two and a half 430 00:22:46,339 --> 00:22:49,747 miles, an alert should sound. It's not 431 00:22:49,771 --> 00:22:51,415 doing anything. There's no alert. 432 00:22:58,535 --> 00:23:00,231 It was very surprising to us that the 433 00:23:00,263 --> 00:23:02,231 cockpit display of traffic in the auttter 434 00:23:02,303 --> 00:23:05,343 didn't provide traffic alerts because 435 00:23:05,359 --> 00:23:07,039 that's a really important defense against 436 00:23:07,087 --> 00:23:10,191 midair collisions. There is something not 437 00:23:10,223 --> 00:23:11,915 right with the alerting function. 438 00:23:15,655 --> 00:23:18,679 Okay folks, in a few seconds we're going 439 00:23:18,687 --> 00:23:19,995 to arrive at the beautiful. 440 00:23:23,915 --> 00:23:26,875 The NTSB must now figure out why a 441 00:23:26,915 --> 00:23:29,575 critical piece of safety equipment failed 442 00:23:35,555 --> 00:23:41,011 Traffic alerting system was installed in 443 00:23:41,083 --> 00:23:44,819 1999. One of 444 00:23:44,827 --> 00:23:47,595 the first in the country. They take a 445 00:23:47,635 --> 00:23:49,035 closer look at the De Havilland 446 00:23:49,075 --> 00:23:51,295 Otter'traffic alerting system. 447 00:23:52,165 --> 00:23:55,253 Looks like the FAA paid for it as part of 448 00:23:55,269 --> 00:23:58,805 an experimental program. The Capstone 449 00:23:58,885 --> 00:24:01,573 project that the FAA sponsored was a 450 00:24:01,629 --> 00:24:03,389 program to reduce mid air collision 451 00:24:03,477 --> 00:24:07,985 accidents in Alaska. In 2015, 452 00:24:08,645 --> 00:24:12,145 the Otter got an upgrade from the FAA. 453 00:24:12,685 --> 00:24:13,945 What kind of upgrade? 454 00:24:17,545 --> 00:24:18,605 Take a look. 455 00:24:21,505 --> 00:24:24,233 They swapped out a Garmin transceer 978. 456 00:24:24,329 --> 00:24:27,049 Yes. And take a look at what wasn't 457 00:24:27,137 --> 00:24:30,641 included in the upgrade. When the traffic 458 00:24:30,713 --> 00:24:33,025 system was upgraded on the Otter, its 459 00:24:33,065 --> 00:24:35,205 alerting function was removed. 460 00:24:37,425 --> 00:24:40,001 The FAA considered the traffic alerting 461 00:24:40,073 --> 00:24:43,161 audio capability to be classified as 462 00:24:43,233 --> 00:24:45,817 immature and no longer part of the 463 00:24:45,841 --> 00:24:48,201 upgraded system. That was a head scratcher 464 00:24:48,233 --> 00:24:51,777 for our team. But even if the Otter pilot 465 00:24:51,841 --> 00:24:54,449 didn't receive an alert, the Beaver pilot 466 00:24:54,497 --> 00:24:56,525 should have received one on his system. 467 00:24:57,705 --> 00:24:59,801 In this part of the world, alerting 468 00:24:59,873 --> 00:25:01,865 systems are neither mandated nor 469 00:25:01,905 --> 00:25:04,505 regulated. Planes can have different 470 00:25:04,585 --> 00:25:07,697 systems or none at all. The Beaver pilot 471 00:25:07,721 --> 00:25:10,201 had been utilizing an iPad that was using 472 00:25:10,233 --> 00:25:13,385 the application for navigating and 473 00:25:13,465 --> 00:25:15,137 understanding where traffic would be in 474 00:25:15,161 --> 00:25:16,485 his surrounding area. 475 00:25:18,105 --> 00:25:21,521 The pilot paid for his own system and 476 00:25:21,553 --> 00:25:23,185 so he would have had a fully functional 477 00:25:23,265 --> 00:25:26,045 system including alerting capabilities. 478 00:25:26,385 --> 00:25:29,445 According to this. Yes. 479 00:25:30,705 --> 00:25:32,625 I think it's clear the Beaver pilot was 480 00:25:32,705 --> 00:25:35,057 concerned about safety. He had gone at his 481 00:25:35,081 --> 00:25:38,249 own expense and installed ADS B equipment 482 00:25:38,297 --> 00:25:41,007 in his airplane that was not required per 483 00:25:41,031 --> 00:25:45,167 regulation. Did the Beavers system also 484 00:25:45,231 --> 00:25:46,995 fail to alert the pilot? 485 00:25:49,815 --> 00:25:52,015 Investigators used the ground station data 486 00:25:52,095 --> 00:25:54,207 to recreate what the Beaver pilot would 487 00:25:54,231 --> 00:25:56,207 have seen and heard in the cockpit leading 488 00:25:56,231 --> 00:25:59,903 up to the crash. The center 489 00:25:59,919 --> 00:26:03,143 is the Beaver. The Otter is at 490 00:26:03,199 --> 00:26:08,763 three miles out. Now there 491 00:26:08,779 --> 00:26:11,299 is no alert warning of the approaching 492 00:26:11,347 --> 00:26:12,055 Otter. 493 00:26:15,115 --> 00:26:19,027 We're missing something. Determining why 494 00:26:19,211 --> 00:26:22,387 neither of the traffic alerting systems in 495 00:26:22,411 --> 00:26:24,803 the airplanes warned the pilots about the 496 00:26:24,819 --> 00:26:26,891 impending collision was something that we 497 00:26:26,923 --> 00:26:29,867 had to sort out in order to figure out why 498 00:26:29,891 --> 00:26:30,975 the collision happened. 499 00:26:36,775 --> 00:26:39,715 Is that everything? Thank you. 500 00:26:42,415 --> 00:26:45,367 With the Beaver's ADSB system destroyed in 501 00:26:45,391 --> 00:26:48,647 the crash, the NTSB turns to the only 502 00:26:48,671 --> 00:26:51,623 evidence that remains. Salvaged parts of 503 00:26:51,639 --> 00:26:53,915 the Otter's traffic alerting system. 504 00:26:54,495 --> 00:26:56,995 Hey, check this out. 505 00:26:59,805 --> 00:27:03,301 It's turned off. A key component 506 00:27:03,373 --> 00:27:05,461 was not operating at the time of the 507 00:27:05,493 --> 00:27:07,985 crash. That is odd. 508 00:27:09,605 --> 00:27:12,661 There was a critical piece of equipment on 509 00:27:12,693 --> 00:27:15,505 board the otter called the GSL71. 510 00:27:16,645 --> 00:27:19,693 The GSL71 is a control panel for the 511 00:27:19,709 --> 00:27:22,637 alerting system. It broadcasts the plane's 512 00:27:22,661 --> 00:27:25,345 altitude to aircraft and ground stations. 513 00:27:28,055 --> 00:27:30,247 Let's see exactly how these components 514 00:27:30,311 --> 00:27:34,207 work. Investigators examined the 515 00:27:34,231 --> 00:27:36,279 role of each component of The Otter's 516 00:27:36,327 --> 00:27:38,695 traffic systems to consider the 517 00:27:38,735 --> 00:27:41,831 consequences of having the GSL71 turned 518 00:27:41,863 --> 00:27:42,435 off. 519 00:27:45,575 --> 00:27:47,315 This is not a simple setup. 520 00:27:49,295 --> 00:27:51,973 So a surprising thing about the system on 521 00:27:51,989 --> 00:27:53,733 the Otter was that it was a mixture of new 522 00:27:53,749 --> 00:27:57,145 and old parts. Look at this. 523 00:28:02,165 --> 00:28:04,425 If the GSL71 is off, 524 00:28:05,805 --> 00:28:09,925 altitude information will not be 525 00:28:09,965 --> 00:28:12,145 broadcast to other aircraft. 526 00:28:14,525 --> 00:28:17,209 If the Otter wasn't broadcasting, then the 527 00:28:17,217 --> 00:28:18,845 Beaver would not have gotten an alert. 528 00:28:20,185 --> 00:28:22,845 Investigators get their biggest lead yet. 529 00:28:24,305 --> 00:28:27,201 Because the GSL71 was off, other aircraft 530 00:28:27,233 --> 00:28:30,641 had no idea what altitude the Otter was 531 00:28:30,673 --> 00:28:32,085 currently operating at. 532 00:28:33,625 --> 00:28:35,809 Was that airplane above him? Below him? 533 00:28:35,897 --> 00:28:38,285 Same altitude? Unsure. 534 00:28:43,605 --> 00:28:45,477 When was the last time the Otter 535 00:28:45,621 --> 00:28:47,305 transmitted altitude data? 536 00:28:49,565 --> 00:28:51,989 Investigators review when the Taquan Air 537 00:28:52,037 --> 00:28:54,461 Otter last broadcast its altitude to 538 00:28:54,493 --> 00:28:55,545 ground stations. 539 00:28:57,925 --> 00:28:59,225 April 29. 540 00:29:06,405 --> 00:29:09,825 The last inspection and maintenance was 541 00:29:11,345 --> 00:29:15,153 April 30, the day after its last 542 00:29:15,209 --> 00:29:18,841 broadcast. The team considers whether the 543 00:29:18,873 --> 00:29:22,345 GSL71 was turned off for maintenance two 544 00:29:22,385 --> 00:29:25,329 weeks before the crash and never turned on 545 00:29:25,377 --> 00:29:28,857 again. We spoke to maintenance personnel, 546 00:29:28,961 --> 00:29:32,265 but during the course of interviews, we 547 00:29:32,305 --> 00:29:35,153 never really were able to completely 548 00:29:35,249 --> 00:29:37,597 understand why the unit was in the off 549 00:29:37,661 --> 00:29:41,173 position. Since the Otter 550 00:29:41,229 --> 00:29:43,701 wasn't broadcasting its altitude, the 551 00:29:43,733 --> 00:29:45,745 Beaver never received an alert. 552 00:29:47,525 --> 00:29:49,741 Why didn't the autopilot check if he was 553 00:29:49,773 --> 00:29:51,677 broadcasting his altitude on the day of 554 00:29:51,701 --> 00:29:52,465 the crash? 555 00:29:55,365 --> 00:29:58,105 I have some additional questions for you. 556 00:30:00,845 --> 00:30:03,229 Were you aware that the control panel was 557 00:30:03,277 --> 00:30:03,865 off? 558 00:30:07,085 --> 00:30:11,197 No. Why not? I saw other 559 00:30:11,221 --> 00:30:13,773 aircraft on the display screen, so that 560 00:30:13,829 --> 00:30:15,465 told me the system was working. 561 00:30:16,845 --> 00:30:18,837 Investigators discover that the pilot 562 00:30:18,901 --> 00:30:21,037 didn't fully understand how all the 563 00:30:21,061 --> 00:30:22,741 components of the traffic surveillance 564 00:30:22,813 --> 00:30:25,945 system worked. No conflict. 565 00:30:26,725 --> 00:30:28,445 We learned that there had been other 566 00:30:28,485 --> 00:30:31,749 pilots in the airplane plane preceding the 567 00:30:31,797 --> 00:30:34,261 accident with the accident pilot who 568 00:30:34,293 --> 00:30:37,077 apparently didn't catch that the GSL71 was 569 00:30:37,101 --> 00:30:39,917 in the off position either. I think on one 570 00:30:39,941 --> 00:30:42,069 of those flights he actually had the chief 571 00:30:42,117 --> 00:30:44,437 pilot of the company with him. And the 572 00:30:44,461 --> 00:30:46,933 GSL71 was still in the off position. And 573 00:30:46,949 --> 00:30:48,893 we know that because the data wasn't 574 00:30:48,949 --> 00:30:50,709 streamed, the pressure altitude wasn't 575 00:30:50,757 --> 00:30:53,933 streamed. Did you check to see 576 00:30:53,949 --> 00:30:57,065 if the GSL unit was on during your pre 577 00:30:57,105 --> 00:30:58,085 flight checklist? 578 00:31:00,785 --> 00:31:03,257 No, it wasn't a piece of equipment that I 579 00:31:03,281 --> 00:31:05,445 ever touched or concerned myself with. 580 00:31:06,305 --> 00:31:08,313 They review the company's pre flight 581 00:31:08,369 --> 00:31:10,977 checklist with the autopilot to understand 582 00:31:11,041 --> 00:31:13,313 why a crucial part of the alerting system 583 00:31:13,369 --> 00:31:14,605 wasn't turned on. 584 00:31:16,625 --> 00:31:20,885 Radio sets, altimeter sets, 585 00:31:22,565 --> 00:31:26,213 fuel checked. It's not 586 00:31:26,229 --> 00:31:27,665 on my pre flight checklist. 587 00:31:34,765 --> 00:31:38,505 Okay, thank you. 588 00:31:40,845 --> 00:31:43,037 Investigators determine the autopilot 589 00:31:43,101 --> 00:31:45,141 wouldn't have checked the status of the 590 00:31:45,173 --> 00:31:48,801 GSL71 in an airline environment. 591 00:31:48,953 --> 00:31:50,257 Something as critical as that would 592 00:31:50,281 --> 00:31:52,577 definitely be on a checklist. And so the 593 00:31:52,601 --> 00:31:55,617 fact that it wasn't might lead him to 594 00:31:55,641 --> 00:31:58,937 think that it wasn't super critical or it 595 00:31:58,961 --> 00:32:00,593 would just not have risen to the level of 596 00:32:00,649 --> 00:32:02,257 something that he would pay attention to 597 00:32:02,281 --> 00:32:03,325 each and every time. 598 00:32:06,905 --> 00:32:09,313 What did you learn from the autopilot? He 599 00:32:09,329 --> 00:32:12,973 didn't know the unit was turned off. It 600 00:32:12,989 --> 00:32:14,945 wasn't on his pre flight checklist. 601 00:32:16,845 --> 00:32:19,149 You have to be so diligent at all times 602 00:32:19,197 --> 00:32:20,309 when you're flying the aircraft, 603 00:32:20,397 --> 00:32:22,405 especially in a busy, busy area like that. 604 00:32:22,565 --> 00:32:24,461 As good as the traffic systems can be, 605 00:32:24,573 --> 00:32:27,637 they can sometimes fail. The team 606 00:32:27,701 --> 00:32:29,997 now knows why neither traffic system 607 00:32:30,061 --> 00:32:33,133 alerted the pilots. It still doesn't 608 00:32:33,189 --> 00:32:35,045 explain why the pilots didn't see each 609 00:32:35,085 --> 00:32:39,057 other on a perfectly clear day. See and 610 00:32:39,081 --> 00:32:42,585 avoid is the system by which pilots are 611 00:32:42,625 --> 00:32:44,281 taught to avoid one another when air 612 00:32:44,313 --> 00:32:46,337 traffic control is not providing positive 613 00:32:46,401 --> 00:32:49,577 separation. It is considered a last line 614 00:32:49,601 --> 00:32:52,385 of defense. And it involves systematically 615 00:32:52,465 --> 00:32:54,545 scanning different parts of the sky 616 00:32:54,705 --> 00:32:57,129 visible through the windscreen to ensure 617 00:32:57,177 --> 00:32:58,809 that there aren't any other aircraft on a 618 00:32:58,817 --> 00:32:59,765 collision course. 619 00:33:03,265 --> 00:33:05,193 Okay, let's check out the pilot's field of 620 00:33:05,209 --> 00:33:08,647 view. NTSB investigators 621 00:33:08,751 --> 00:33:11,111 consider exactly what the pilots could see 622 00:33:11,183 --> 00:33:13,155 from the cockpits of their airplanes. 623 00:33:17,135 --> 00:33:20,151 So the Beaver pilot would have been doing 624 00:33:20,183 --> 00:33:23,235 his scans looking left, 625 00:33:24,975 --> 00:33:28,115 no problem looking right. 626 00:33:30,775 --> 00:33:33,055 There was a passenger in the front seat 627 00:33:33,175 --> 00:33:34,515 restricting his view, 628 00:33:37,785 --> 00:33:40,193 and the otter was to the right, coming 629 00:33:40,249 --> 00:33:41,245 from behind. 630 00:33:43,905 --> 00:33:46,833 The passenger sitting in your seat might 631 00:33:46,849 --> 00:33:49,121 have been able to see it, but not the 632 00:33:49,153 --> 00:33:52,257 pilot. What about looking about through 633 00:33:52,281 --> 00:33:53,525 the cabin? 634 00:33:56,065 --> 00:33:59,041 I don't think so. The windows are too 635 00:33:59,113 --> 00:34:01,205 small and passengers are in the way. 636 00:34:03,675 --> 00:34:06,203 There's no way he could have seen the 637 00:34:06,219 --> 00:34:08,187 otter approaching from behind and to the 638 00:34:08,211 --> 00:34:11,435 right. The Beaver has issues with 639 00:34:11,475 --> 00:34:13,435 visibility because of the structural 640 00:34:13,515 --> 00:34:15,603 design of the airplane. You have door 641 00:34:15,659 --> 00:34:18,283 posts and window posts and overhead 642 00:34:18,339 --> 00:34:20,291 structure, etc. That does obscure your 643 00:34:20,323 --> 00:34:23,387 view. And of course, in the old days, 644 00:34:23,451 --> 00:34:25,947 that wasn't really a huge concern because 645 00:34:25,971 --> 00:34:27,347 of course, there was a lot less airplanes 646 00:34:27,371 --> 00:34:31,402 in the sky. The Otter pilot might 647 00:34:31,418 --> 00:34:34,426 have had a perfect view to the left and 648 00:34:34,490 --> 00:34:38,306 straight ahead. Let's figure that 649 00:34:38,330 --> 00:34:38,894 out. 650 00:34:44,194 --> 00:34:46,626 So the Otter pilot said he was lining up 651 00:34:46,650 --> 00:34:50,994 the waterfall to his right. So this was 652 00:34:51,034 --> 00:34:53,134 the pilot's field of view. 653 00:34:54,815 --> 00:34:57,095 Investigators consider what the autopilot 654 00:34:57,135 --> 00:34:59,115 could see at the time of the crash. 655 00:35:00,935 --> 00:35:03,847 So let's assume that he was looking to his 656 00:35:03,871 --> 00:35:07,471 right, say about 2:00. But the pilot 657 00:35:07,503 --> 00:35:09,279 was adamant that he was still doing his 658 00:35:09,327 --> 00:35:12,087 full visual scans left and right, up and 659 00:35:12,111 --> 00:35:15,967 down. So what would he see 660 00:35:16,071 --> 00:35:19,015 if he looked to his left towards the 661 00:35:19,055 --> 00:35:23,781 beaver using 662 00:35:23,813 --> 00:35:27,197 a 3D scan of an Otter cockpit. The team 663 00:35:27,261 --> 00:35:29,533 recreates the pilot's view out of the left 664 00:35:29,589 --> 00:35:31,357 windshield in the moments before the 665 00:35:31,381 --> 00:35:32,025 collision. 666 00:35:34,885 --> 00:35:36,985 This is just minutes before the collision. 667 00:35:38,525 --> 00:35:40,865 Beaver is still three miles away, 668 00:35:42,285 --> 00:35:44,705 roughly. In this area of the windscreen, 669 00:35:45,385 --> 00:35:47,697 the beaver is little more than a speck on 670 00:35:47,721 --> 00:35:51,097 the horizon. It's hard to pick 671 00:35:51,121 --> 00:35:52,817 out the beaver against the dark mountains 672 00:35:52,841 --> 00:35:55,361 in the distance. When two objects are 673 00:35:55,393 --> 00:35:57,689 converging, there is little relative 674 00:35:57,737 --> 00:35:59,761 motion in a pilot's visual field to 675 00:35:59,793 --> 00:36:02,845 attract a pilot's attention. Okay, 676 00:36:03,545 --> 00:36:05,977 we've got one. Three miles out, three 677 00:36:06,001 --> 00:36:09,005 o'clock. Opposite direction. 678 00:36:10,025 --> 00:36:11,125 No conflict. 679 00:36:14,125 --> 00:36:17,333 Beaver's an eighth mile away. Still don't 680 00:36:17,349 --> 00:36:21,045 see it. The window post, called an A 681 00:36:21,085 --> 00:36:23,829 pillar, obstructs the view of the beaver. 682 00:36:23,997 --> 00:36:25,629 Okay, we're coming up on the moment of 683 00:36:25,677 --> 00:36:26,265 impact. 684 00:36:29,405 --> 00:36:32,253 Beaver came out of nowhere. I didn't see 685 00:36:32,269 --> 00:36:36,237 it until impact. The Otter's ADSB system 686 00:36:36,301 --> 00:36:38,365 doesn't have the alerting capability to 687 00:36:38,405 --> 00:36:41,897 warn of the other plane. And the 688 00:36:41,921 --> 00:36:44,165 pilot's view of it is obstructed. 689 00:36:45,185 --> 00:36:48,377 Okay, folks, in a few seconds, we're gonna 690 00:36:48,401 --> 00:36:49,805 pass our famous mah. 691 00:36:54,225 --> 00:36:57,753 The animation was fascinating because it 692 00:36:57,809 --> 00:37:00,785 showed how almost perfectly the beaver was 693 00:37:00,825 --> 00:37:03,217 obscured by the window post in the cockpit 694 00:37:03,241 --> 00:37:05,285 of the Otter from the pilot's perspective. 695 00:37:05,645 --> 00:37:08,189 And it wasn't until the last half second 696 00:37:08,237 --> 00:37:10,309 or so that it sort of blossomed from 697 00:37:10,357 --> 00:37:13,465 behind the post and became a red flash. 698 00:37:15,045 --> 00:37:17,505 But they can't be completely certain. 699 00:37:19,205 --> 00:37:22,117 It's hard to know for sure. This 700 00:37:22,181 --> 00:37:25,557 perspective is going to change depending 701 00:37:25,581 --> 00:37:28,677 on where his seat is set and where his 702 00:37:28,701 --> 00:37:31,661 head is. Investigators need more 703 00:37:31,733 --> 00:37:35,043 information. We can 704 00:37:35,139 --> 00:37:38,875 change sight lines, we can adjust angles, 705 00:37:38,995 --> 00:37:42,251 we can adjust views, but we 706 00:37:42,363 --> 00:37:44,363 do not have the ab. In fact, the pilot's 707 00:37:44,419 --> 00:37:47,243 position at any point in time during that 708 00:37:47,299 --> 00:37:47,895 flight. 709 00:37:52,755 --> 00:37:55,979 The team performs a study using 27 710 00:37:56,067 --> 00:37:58,355 different eye positions to evaluate how 711 00:37:58,395 --> 00:38:00,107 the a pillar would have blocked the 712 00:38:00,131 --> 00:38:03,187 beaver. From the autopilot's view. The 713 00:38:03,211 --> 00:38:06,575 beaver is mostly hidden except for here. 714 00:38:08,195 --> 00:38:10,483 It's hard to be 100% certain without 715 00:38:10,619 --> 00:38:13,295 knowing the pilot's exact seat position. 716 00:38:17,235 --> 00:38:19,451 What about the cameras that we recovered 717 00:38:19,483 --> 00:38:21,803 from the wreckage? Maybe there's something 718 00:38:21,819 --> 00:38:24,255 on them. I'll check on it. 719 00:38:25,635 --> 00:38:28,375 Based on it being an air tour operation 720 00:38:28,555 --> 00:38:31,359 being in 2019, fortunately, we were able 721 00:38:31,407 --> 00:38:34,511 to locate quite a bit of still imagery and 722 00:38:34,583 --> 00:38:38,795 video. Okay, let's see what we've got. 723 00:38:40,895 --> 00:38:43,635 After several weeks of painstaking work, 724 00:38:43,975 --> 00:38:46,511 investigators review images taken by the 725 00:38:46,543 --> 00:38:47,755 Otter passengers. 726 00:38:51,815 --> 00:38:53,595 Now there's nothing here. 727 00:38:55,195 --> 00:38:57,531 There are no pictures taken near the time 728 00:38:57,563 --> 00:39:00,187 of the collision. Let's check out the 729 00:39:00,211 --> 00:39:02,015 photos taken from the Beaver. 730 00:39:05,555 --> 00:39:09,291 Whoa. They find A photo of 731 00:39:09,323 --> 00:39:11,643 the otter taken by a passenger in the 732 00:39:11,659 --> 00:39:14,603 Beaver. It was eerie and disturbing to see 733 00:39:14,619 --> 00:39:18,347 the photos taken by the passengers. Let's 734 00:39:18,371 --> 00:39:19,615 take a closer look. 735 00:39:23,615 --> 00:39:26,135 The photo of the approaching otter was 736 00:39:26,175 --> 00:39:28,275 taken seconds before impact. 737 00:39:34,215 --> 00:39:36,959 It was a moving experience. You knew it 738 00:39:36,967 --> 00:39:38,623 was going to be the last moments for some 739 00:39:38,639 --> 00:39:39,795 of those people. 740 00:39:42,895 --> 00:39:46,551 Zoom in. But can it answer the question 741 00:39:46,623 --> 00:39:48,767 of whether the otterilot could see the 742 00:39:48,791 --> 00:39:52,565 beaver? I can see into the outer cockpit. 743 00:39:53,625 --> 00:39:56,205 It's the break the investigators needed. 744 00:39:57,225 --> 00:40:00,297 Try to zoom in a little bit more. The 745 00:40:00,321 --> 00:40:03,217 photo captures the otter's exact position. 746 00:40:03,401 --> 00:40:06,433 The A pillar is blocking the pilot's head. 747 00:40:06,609 --> 00:40:08,409 If we can't see the Otter pilot's head 748 00:40:08,457 --> 00:40:10,473 from this perspective, he wouldn't have 749 00:40:10,489 --> 00:40:13,433 seen the beaver. Investigators are now 750 00:40:13,529 --> 00:40:15,793 certain that for almost three minutes 751 00:40:15,889 --> 00:40:17,721 before the collision, the otter's 752 00:40:17,753 --> 00:40:19,977 windshield structure blocked the pilot's 753 00:40:20,001 --> 00:40:22,265 view of the approaching beaver. It's 754 00:40:22,305 --> 00:40:24,489 crucial for us to understand that at that 755 00:40:24,537 --> 00:40:27,753 point the Otter pilot had very limited 756 00:40:27,809 --> 00:40:30,297 chance of avoiding that collision due to 757 00:40:30,361 --> 00:40:33,025 his sight being obscured by that aircraft 758 00:40:33,065 --> 00:40:33,765 structure. 759 00:40:36,305 --> 00:40:38,681 Investigators now understand why the 760 00:40:38,713 --> 00:40:40,729 Mountain Air Beaver and the Taquane Air 761 00:40:40,777 --> 00:40:42,045 Otter collided. 762 00:40:44,405 --> 00:40:47,597 Okay folks, in a few seconds we're gonna 763 00:40:47,621 --> 00:40:48,745 pass our famous. 764 00:40:50,325 --> 00:40:53,341 Neither pilot could see nor be alerted to 765 00:40:53,413 --> 00:40:55,525 how close their aircraft were to each 766 00:40:55,565 --> 00:40:56,825 other. Hang on everyone. 767 00:40:59,445 --> 00:41:00,625 RA for impact. 768 00:41:03,485 --> 00:41:05,957 You just can't afford not have a traffic 769 00:41:06,021 --> 00:41:08,941 system when it's so busy. Is that in 770 00:41:08,973 --> 00:41:10,701 terrain like that when the pilot is so 771 00:41:10,733 --> 00:41:12,587 darn busy he needs all the help he can 772 00:41:12,611 --> 00:41:16,419 get. The NTSB's final report 773 00:41:16,547 --> 00:41:19,067 highlights the limitation of see and avoid 774 00:41:19,131 --> 00:41:22,491 for pilots and recommends new rules for 775 00:41:22,523 --> 00:41:25,155 preventing the downgrading or disabling of 776 00:41:25,195 --> 00:41:28,195 traffic alerting systems. This accident in 777 00:41:28,695 --> 00:41:30,651 a nutshell to me is about the rolling back 778 00:41:30,683 --> 00:41:32,435 of safety protections without anybody 779 00:41:32,475 --> 00:41:33,787 taking a critical look at what they were 780 00:41:33,811 --> 00:41:37,899 doing. The NTSB recommends 781 00:41:37,947 --> 00:41:40,595 regulations requiring mandatory air 782 00:41:40,635 --> 00:41:43,495 traffic alerting for air tour operators in 783 00:41:43,535 --> 00:41:46,687 high traffic areas. I have 784 00:41:46,711 --> 00:41:48,671 worked a number of mid air collisions 785 00:41:48,783 --> 00:41:52,439 during my career here at the NTSB and this 786 00:41:52,487 --> 00:41:55,655 accident was very preventable. There are 787 00:41:55,695 --> 00:41:58,263 limitations, as all of us all well know 788 00:41:58,319 --> 00:42:01,519 with the concept of seea and avoid and the 789 00:42:01,607 --> 00:42:04,303 technology that exists today should be in 790 00:42:04,319 --> 00:42:06,799 these aircraft to help reduce these number 791 00:42:06,807 --> 00:42:07,855 of collisions that take place.