On 6 April 1993, a crew member accidentally deploys the slats on China Eastern Airlines Flight 583 over the Pacific Ocean, causing severe oscillations. The aircraft later lands safely at Shemya Air Force Base in Alaska. Two passengers die from their injuries.
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00:00After declaring an emergency...
00:04Injured passengers due to severe turbulence.
00:07China Eastern Airlines Flight 583
00:10seeks permission to land at a restricted U.S. military base in the Bering Sea.
00:15300 feet.
00:16The Pentagon have to take a look at what's happening.
00:19Is this a ruse to take a look at our radar site?
00:24Once the plane is examined,
00:26officials discount the possibility of espionage.
00:31Never seen anything like it before.
00:34This accident was definitely a catastrophic event.
00:39Two passengers died.
00:41The flight data recorder shows an erratic flight path.
00:45Wow.
00:47Being on this airplane was like being on a roller coaster.
00:53Only the cause is not what the pilots reported.
00:57The weather was clear.
00:58It's unlikely there was any turbulence.
01:00That changes everything.
01:01That changes everything.
01:02The crew of China Eastern Airlines Flight 583
01:05is on an overnight flight from Beijing to Los Angeles.
01:09Approaching 39 degrees north, 172 degrees east.
01:10The crew of China Eastern Airlines Flight 583 is on an overnight flight from Beijing to Los Angeles.
01:22Approaching 39 degrees north, 172 degrees east.
01:23The crew of China Eastern Airlines Flight 583 is on an overnight flight from Beijing to Los Angeles.
01:35Approaching 39 degrees north, 172 degrees east.
01:38All good back there?
01:40In 1993, China Eastern Airlines was a fairly new company.
01:50It had only been around a couple of years.
01:55The entire China aviation market was rapidly changing.
02:01China Eastern Airlines began operation in 1988.
02:08It was an exciting time with people finding that they suddenly had the ability to start traveling overseas.
02:18Two hundred and thirty-five passengers have just finished their meal service.
02:27Some rest while others watch a movie.
02:33You press the switch and the air conditioning pops up.
02:39The captain is a veteran pilot with more than 8,000 flying hours.
02:44You try.
02:48The captain was flying the airplane from the right seat because he was training the person who was in the left seat to be a new captain.
02:57His first officer is a seasoned pilot, but new to this plane, an MD-11.
03:10McDonnell Douglas developed the MD-11 as a fuel-efficient option for long-haul flights.
03:17In the early 1990s, approximately 100 of them were in service worldwide.
03:23The MD-11 was an upgraded version of the DC-10.
03:29It was more efficient flying at cruise speeds, although it had an automated system for flying the aircraft.
03:36It was also changed in such a way that it was very responsive to pilot input, if they were flying it manually.
03:42This plane is one of five the airline bought to grow its international service.
03:53Shield check numbers look good.
03:55Copy that.
04:01During the cruise portion of the flight, things are fairly routine.
04:05Flying at 33,000 feet, the autopilot's on.
04:14They've completed the first leg of the flight from Beijing to Shanghai, and are now flying over the North Pacific bound for Los Angeles.
04:22Ladies and gentlemen, the cabin crew is now passing out customs declaration cards, which must be completed before entering the United States.
04:35For many passengers, this is their first overseas flight. The process is unfamiliar.
04:48Do you postal code of the hotel we're staying?
04:51Yeah.
04:57Something's going on with the speed indicator.
05:00The crew has pre-programmed a cruising speed into the computer, which is now telling them to fly at a different speed.
05:06The flight control computer is making numerous checks of various systems, including air temperature, air speed, fuel burn, etc.
05:15And they sometimes give suggestions to the pilots of how they can fly more efficiently, in this case, fly more slowly.
05:24Hmm. That didn't fix it.
05:27The captain tries to clear the computer's suggested speed.
05:30It's not a big concern. The airplane's flying fine. But it's just odd. And the captain tries to sort it out.
05:41I'm going to try this.
05:47What's that?
05:49While they're sorting out the speed issue, the plane seems to hit some turbulence.
05:55They start feeling this buffeting. And the airplane's shaking around. Definitely something that will get any pilot's attention.
06:05Suddenly, one of the worst things a pilot can hear. A stall warning alarm.
06:13I'm taking control.
06:15The nose of the plane is pitching up, which shouldn't happen while cruising at altitude with the autopilot on.
06:21He needs to get the nose down, because the airplane truly stalls. It no longer has enough lift to stay flying. It's going to start dropping from the sky.
06:31The captain pushes the yoke with enough force to override the autopilot.
06:36Autopilot. Off.
06:38Off.
06:41And to avoid a stall.
06:47But now the nose pitch is too far down.
06:50Pull up.
06:54The effects of the dive are felt even more severely in the cabin.
06:57Trying to gain control of the airplane. Trying to understand what's going on. The adrenal level goes dramatic real quick.
07:11The captain uses all of his strength to keep the plane from diving.
07:15But the aircraft pitches up steeper than expected. Exerting massive G-forces on everyone and everything in the cabin.
07:26Turbulence! Seatbelt to everyone!
07:32What's going on?
07:34In essence, this airplane was pitching up, then pitching down. It's almost like being on a roller coaster.
07:41The captain attempts to level the plane, but it goes into an even more extreme dive.
07:56It happens so fast. The forces are so great.
08:01You wouldn't have time to even think of trying to get your seatbelt on.
08:06Eight degrees, no doubt.
08:09Nine, ten!
08:13The captain halts the terrifying dive.
08:17With severe consequences for unbuckled passengers.
08:21You're being slammed back into your seat and then thrown back onto whatever might be below you at the time.
08:28As the plane is tossed up and down, the crew avoids a stall by keeping the nose from pitching up too much.
08:38But the nose downs are a problem.
08:40The pitch downs were more extreme than the pitch ups.
08:44And the aircraft is losing altitude.
08:46On the next oscillation, the plane pitches down an astonishing 24 degrees.
08:55The captain battles to stop the plane from diving, while passengers struggle for their lives.
09:11A lot's going on. It's a dark night. He's used these instruments.
09:22Forces are nothing like he's ever seen before.
09:25And so it takes several of these cycles of this porpoicine until finally he is able to get the airplane back to level.
09:3130 seconds in, the oscillations lessen and the plane begins to stabilize.
09:44Levels at zero degrees.
09:45To the crew, that probably felt like it lasted, you know, an hour.
09:52In reality, it lasted a little less than a minute.
10:01What just happened?
10:04No idea.
10:06Even with the autopilot on, there's no time to relax.
10:10There's no guarantee that what happened won't happen again.
10:16They're flying over the vast Pacific Ocean, nowhere near an airport.
10:21And several passengers are seriously wounded.
10:25We have many injuries.
10:30We need to get this plane on the ground.
10:37China Eastern Airlines Flight 583 is back at 33,000 feet.
10:42Now it needs a place to land.
10:45235 passengers on board. Unknown number injured.
10:49Call it in now.
10:51Flight 583, requesting the nearest airport. This is an emergency.
10:56Airspeed?
11:00298 knots.
11:02Angle of attack?
11:04Zero.
11:05For now, everything seems to be working.
11:09All they know at the moment is the airplane's flying, but it appears to be fine.
11:14But then again, until we land and get out and look at it, we don't know.
11:18With injured passengers on board, the captain can't take the risk of flying 3,700 miles to their destination, Los Angeles.
11:30We're 39 degrees north, 176 east.
11:34Copy. Please stand by.
11:35The crew considers where they might land.
11:39Are we closer to Russia or to the U.S.?
11:42This far out over the Pacific, mainland Russia is 2200 miles to the northwest.
11:51Anchorage, Alaska is the same distance to the northeast.
11:54They're in one of the few places in the world where there's nothing really close by.
12:01Ladies and gentlemen, the plane encountered severe turbulence and the damage is being assessed.
12:08Please cooperate and be patient. We are planning for an emergency landing.
12:13Flight 583 is overseen by air traffic control in Honolulu, 2,000 miles away.
12:21What is your emergency?
12:23Injured passengers due to severe turbulence.
12:28Stand by, please.
12:30It's an unusual situation.
12:33A civilian Chinese airplane in international airspace in urgent need of an airport.
12:39Looks like it's either Anchorage or Shemya.
12:42Waiting for clearance.
12:46Shemya, a tiny island on the western tip of Alaska's Aleutian Island chain,
12:51is about 1,000 miles away.
12:54Anchorage is twice as far.
12:57Because it's an air force base, Shemya has medical staff and equipment to treat injured passengers.
13:03Shemya is basically an island in the middle of nowhere.
13:08Operated by the U.S. Air Force is strictly for military operation.
13:14There are no commercial flights.
13:16The decision to allow the China Eastern Airlines flight to land is taken to the highest levels.
13:25The Pentagon would have to take a look at what's happening here.
13:29Is this a real emergency or is this a ruse to take a look at our big radar site we have there?
13:36I imagine there was a lot of discussion going on from a security point of view.
13:43Clear to divert to Shemya.
13:46We're clear to divert to Shemya.
13:47The captain had a choice to make. Do I go to the closest available runway, which was Shemya, or do I go further on to Anchorage, which might be catastrophic had there been damage to the aircraft?
14:01Okay, we're going to Shemya.
14:06We have received permission to land at Shemya Air Force Base. Damage to our aircraft is unknown.
14:14Can we get a weather report?
14:18The crew prepares for a difficult night landing on an airstrip they've never seen before with unknown damage to their airplane.
14:27Shemya has extreme weather. Heavy cloud cover, fog, and high winds is the norm.
14:34After a nerve-wracking two hours in the air, the plane is now only 40 miles from the airbase.
14:41Altimeters, set.
14:43They really don't know what's going to happen when they slow up.
14:48Did the elevators get damaged? Will the landing gear come down?
14:52There's a lot of things they've got to be concerned about.
14:56As they get closer, the weather intensifies.
15:01Islas armed. Runway 28.
15:05The crew connects to an instrument landing system that uses radio signals to guide them in.
15:112,000 feet.
15:13The crew at this point is going to be under a good amount of stress and pressure to make sure that they do it right the first time.
15:20Wanting to get the people to help as quickly as possible.
15:29Autopilot off.
15:31Taking control.
15:33They're now only six miles from the runway.
15:36Gear down.
15:37Go.
15:39Go.
15:47Land the gears down.
15:48500 feet.
16:02400 feet.
16:06300 feet.
16:08The ILS gets the plane as far as 200 feet above the ground.
16:12Then the captain has to fly by sight.
16:15I have touched down.
16:26I have touched down.
16:43The emergency is over.
16:45The plane is safely on the ground.
16:55Medical teams immediately assess passengers.
16:59The findings are grim.
17:02149 people are injured.
17:04Dozens of passengers and crew are taken to hospital.
17:09One passenger is dead.
17:11Another is fatally wounded.
17:14This accident was definitely a catastrophic event.
17:18Many, many passengers and flight attendants were seriously injured.
17:33Passengers who are well enough to travel are flown to Anchorage International Airport and transferred to hospital for treatment there.
17:39At that time, I think I would die.
17:40Of course, surely I would die.
17:42A team of investigators from the National Transportation Safety Board, or NTSB, flies in from Washington.
17:58Greg Feith leads the investigation.
18:03Never knew anything was wrong with it from here.
18:11They did land on U.S. territory, and so we were going to conduct the investigation.
18:19And because it was an MD-11, it was a relatively new airplane.
18:23I'll go check inside.
18:25We needed to find out what really happened.
18:27As soon as investigators arrive at Shemya, they inspect the aircraft for signs of damage.
18:44I'll go check out the cockpit.
18:52We didn't have a lot of information.
18:54We knew that there had been an emergency landing, that the airplane had encountered severe turbulence.
19:00With that kind of information, you can build a lot of different storylines.
19:07The cockpit looked normal.
19:12But as soon as you looked down the aisle, it looked like a bomb had gone off.
19:16Never seen anything like it before.
19:25Row 15, bend down on seats B and C.
19:34Seat 23B, signs of impact damage.
19:38The cabin gives them a glimpse into the tragedy that unfolded during the flight.
19:43There was a lot of baggage that had come out of the overheads.
19:48Broken glasses, broken dishes.
19:50They are basically lethal weapons if they are flying through the air.
19:55Hey, check out those marks.
19:59Likely scuff marks from shoes.
20:01That was really disturbing because passengers, they had to have been floating not only in space, but they had to have rotated so that their feet were above their head.
20:17Seems like there was a sudden pitch down.
20:21The damage is worse in the aft section.
20:36Someone got badly hurt here.
20:38People in the back are more likely to get injured.
20:45That tail of the airplane tends to get whipped about, almost like a fishtail.
20:51Let's see if we can find some passengers that are well enough to talk to us.
20:55We really needed statements from passengers and flight attendants who had experienced the violence.
21:06They were going to give us a first-hand account of what really took place.
21:10Thanks for coming in today.
21:23Okay.
21:25When the incident happened, what's the first thing you remember?
21:31The plane started to shake.
21:33Then it went up and down like this.
21:35The shaking could be the result of turbulence.
21:40How quickly did this happen?
21:42So fast.
21:44I think I'm lucky to be alive.
21:59When the plane started shaking, did the crew give a turbulence warning?
22:02One of the common causes of turbulence tends to be bad weather, such as rain or hail storms.
22:16If the turbulence is unforeseen, passengers who don't have their seat belts on are a much greater risk for injury.
22:24Did you see out a window? Was there any bad weather?
22:37Not that I could see.
22:44They described that the flight was actually relatively smooth.
22:48They didn't notice any kind of turbulence.
22:51There was nothing unusual about the flight leading up to the main event.
23:01Investigators turned to the weather reports from the day of the incident.
23:04This isn't what I expected.
23:05This isn't what I expected.
23:07The weather was clear.
23:09It's unlikely there was any turbulence.
23:13That changes everything.
23:17What about the elevators?
23:23Definitely worth a look.
23:24A damaged elevator could have led to a loss of control.
23:32We had to determine whether or not there was a problem.
23:38Elevators are hinged flaps on the trailing edge of the horizontal stabilizer.
23:43When the pilot pushes or pulls on the control column, the elevators respond by rising or lowering, creating pitch.
23:55Investigators look for any exterior signs of elevator damage.
23:59Everything looks good on the outside.
24:02I'll check for internal damage.
24:05We use what's called the tap test.
24:07And it's a very simple test.
24:10And in fact, it's done with a quarter.
24:14It should sound solid.
24:18If you hear a hollow type of sound, that's a very good indication that there is a delamination in one or multiple layers of that composite material.
24:29I'm hearing nothing out of the ordinary.
24:30After we cleared the elevators, we still had to understand what may have caused this airframe buffet.
24:40No substructure failures or anomalies were found.
24:45Nothing wrong with the elevators.
24:48Then what else?
24:49What did the captain have to say?
24:57Check the status of his interview.
25:06We wanted to know what he was doing as far as his duties and responsibilities leading up to the upset.
25:12I'm taking control.
25:16I'm taking control.
25:27Hey, you're not going to believe this.
25:29Page 22.
25:31NTSB investigators turn to the captain's account of China Eastern Airlines Flight 583's high altitude incident.
25:41He mentions turbulence before the onset of the incident.
25:44We knew there wasn't any.
25:46That's not all. Keep reading.
25:50He noticed the slots were extended?
25:53Yep.
25:54The MD-11 has eight slats on the leading edge of each wing.
26:03When extended, they change the curvature of the wing, creating more surface area.
26:09Used in tandem with the flaps, they provide extra lift during takeoff.
26:14That's weird.
26:16Why would the slats be extended during cruise?
26:17Investigators now have a very promising lead.
26:27There's no reason to deploy slats at 33,000 feet.
26:33Soon as you would see that the slats had extended at that altitude, it cruised, that would be the alarm bell.
26:38If the slats were out, that would explain the pitch-up described by the passengers.
26:48They're controlled by this handle here.
26:52You should check the entire slats system.
26:58We had to determine whether one or more of the components in that slats system had either malfunctioned or failed.
27:05First look is clean, no obvious signs of damage.
27:19We had to access all the mechanical linkages.
27:23There's hydraulic valves, electrical mechanical systems.
27:27So we had to make the determination whether or not they were functioning as designed.
27:31Okay, let's test them.
27:34Extend the slats.
27:39There's one handle in the cockpit that controls both the slats and the flaps.
27:48Typically the slats are deployed first, so when you pull it back to the first notch, the slats get deployed.
27:55You pull it back further, the flaps get deployed.
27:57It all seems to be working fine.
28:02I've not seen any mechanical issues at all.
28:06They examined the whole system and they extended normally, they retracted normally.
28:11There was no obvious damage to the aircraft.
28:13I still think the slats are part of the problem.
28:19Maybe it wasn't mechanical.
28:23Good thought.
28:26Maybe it wasn't.
28:28Everything showed that the airplane was perfectly fine to fly.
28:31And so the investigation would focus to what the pilots did or did not do that caused the upset.
28:44Did the pilots somehow deploy the slats at high altitude?
28:48Now we had to determine whether or not those slats had been deployed inadvertently.
28:57You got all the reports?
28:59Yep.
29:02Have any pilots accidentally deployed the slat handle in an MD-11?
29:06They review old incident reports.
29:10We do what's called a look back.
29:16So we're looking at whether or not this is an isolated event or a systemic problem.
29:21Hey, look at this.
29:26What have you got?
29:27Ten incidents in two years.
29:35Clipboard fell on the handle.
29:37First officer rested his arm on the handle.
29:40Slats extend in cruise flight.
29:46There had been other events with this particular system, either an uncommanded or inadvertent deployment of the slats.
29:5350% were due to some sort of pilot contact with the slat handle.
30:00If the pilot didn't know he knocked the handle, he probably didn't hit it that hard.
30:05So it could have moved to the slats only position.
30:11Deploying the slats at high speed would trigger the buffeting, which was likely misconstrued as turbulence.
30:18What was happening in the cockpit right before the buffeting started?
30:32The captain said he was using the control keypad.
30:36Here.
30:39They are really close together.
30:40Investigators have a new theory. A simple movement could have triggered the entire chain of events.
30:50We've got to see how easy it is to knock this handle out of place.
30:54Investigators test whether the crew of China Eastern Airlines Flight 583 could have inadvertently knocked the slat handle out of position during flight.
31:11Ready? Ready.
31:15Hey, Muth.
31:16Now, the first officer was sitting in the left seat, so he could have knocked it.
31:20The captain said he was playing with the keypad.
31:25They tried different techniques about, okay, if you hit the handle from the right side back, you hit the handle from the front side back, what would it take to jar the handle out of position?
31:38Hang on, let me try something.
31:40Bingo. That's what the captain was doing when the buffeting started.
31:47Didn't take much force either.
31:50It's a major breakthrough.
31:54Proof that the handle could have been accidentally moved while the captain reached for the keypad.
31:59It was real easy during normal movement using the keypad on the center pedestal to inadvertently strike the handle and cause an uncommanded slat deployment.
32:17Investigators have uncovered a dangerous design flaw in the MD-11.
32:22So the handle probably moved in flight, and then the captain retracted the slats.
32:32The captain said that he saw that the slat handle had been out of position at about the same time the stall warning system triggered.
32:40He immediately moved the slat handle back into the retract position.
32:47The slats were fully extended for just seconds.
32:50Now, that explains the initial pitch-up, but there has to be more to it than that.
32:57I mean, the plane went up and down several times. The slats wouldn't have caused that.
33:01Investigators still don't understand why flight 583 experienced so many extreme oscillations.
33:16The cockpit voice recorder would record for 30 minutes and override itself. So we didn't have that information.
33:26However, with the flight data recorder, we could see control positions, we could gain other information.
33:31Okay, first up, let's look at pitch.
33:35So we have five big oscillations in roughly 20 seconds.
33:40Biggest pitch-up is here.
33:43Oscillation one, 9.5 degrees.
33:47Biggest pitch down happens here, minus 24 degrees, oscillation number four.
33:52Oscillation number four.
33:54For the first time, they can see the severity of the oscillations passengers describe.
34:00And it starts to stabilize here.
34:06The team launches into a second-by-second analysis of the first pitch-up.
34:10The slats were extended here during the beginning of the first pitch-up.
34:19It's gradual at first.
34:22Is the autopilot on?
34:25So it's on for the first few seconds.
34:31And it would have been fighting to bring the nose down.
34:33When the slats deploy, the airplane will have a natural nose or pitch-up tendency.
34:41With the autopilot engaged, it will actually correct for that pitch-up and return the airplane to a level attitude.
34:48But the autopilot's losing the battle.
34:54The pitch keeps increasing, and that would trigger the stall warning.
34:57Yep.
35:04The stall warning turns on here.
35:06A few seconds later, the autopilot disengages, and now the nose dives down sharply.
35:12I'm taking control.
35:16Autopilot off.
35:27So the captain's at the controls when the big drop happens.
35:32Show me the elevator data.
35:38Wow.
35:41So the captain made some elevator inputs, starting right here.
35:45That is a huge nose-down command.
35:52It's an overcorrection.
35:54And I think I know why.
35:57I'm taking control.
36:02Autopilots are designed so they won't just let go easily.
36:07You don't want somebody just accidentally bumping against the controls to suddenly knock the autopilot off.
36:15He felt the resistance and pushed against that resistance of the autopilot, disengaging it.
36:21Unfortunately, that led to an excessive amount of nose-down elevator command.
36:31He started a chain reaction of pushing and pulling too hard on the yoke.
36:40At high altitude, the pitch forces are very light on the yoke.
36:44So when he pulls back to get the nose up, he's putting in too much up force.
36:52It goes up too high.
36:53He pitches down.
36:54It goes down too low.
36:55And he puts in several cycles on the control yoke.
36:58Trying to get back to normal.
36:59It's called a pilot-induced oscillation, or PIO.
37:00The pilot overcorrects, and the plane responds, creating increasing
37:07pressure.
37:08It's called a pilot-induced oscillation, or PIO.
37:13The pilot overcorrects, and the plane responds, creating increasingly uncontrollable movements.
37:32Once you get into the oscillation, it's hard to stop.
37:38Everything's happening fast.
37:45We were able to calculate that the occupants of the airplane experienced 1.24 negative Gs,
37:55and two positive Gs.
37:58No wonder there were so many injuries, including two fatalities.
38:03He did get the plane back under control.
38:08It just took a while.
38:11Pilot-induced oscillations can cause extreme stresses on the aircraft.
38:16Usually the best course of action is to put in less control force.
38:21Once that happens, you can have a nice stable flight.
38:24So why would an experienced captain struggle so long to get a plane back under control?
38:39Long day ahead.
38:41Don't need this.
38:43I pulled the captain's files.
38:46Investigators turned their attention to the captain of Flight 583's training,
38:51to determine why he repeatedly overcorrected with his control column.
38:56He had over 1,300 hours on the MD-11.
38:59There should be plenty.
39:01He flew other passenger jets too.
39:04The captain had flown the Lucians.
39:09He had flown Airbus 300s.
39:11He had experience with big aircraft.
39:14He had experience with high-altitude flight.
39:17Everything would indicate that he was well-qualified to fly the airplane.
39:22No complaints.
39:24No prior accidents.
39:27He's clean as a whistle.
39:30The captain passed all of his MD-11 training without incident.
39:35He even took a refresher course a few weeks before the accident flight.
39:43Let me see the training manual.
39:50Investigators take a closer look at the training the captain received.
39:55A critical aspect of accident investigation when you're looking at an event like this is pilot training.
40:02The captain did go through a very comprehensive textbook or classroom training.
40:08Find anything?
40:10Actually, it's what I didn't find that interests me.
40:17No simulator training.
40:20None?
40:21None.
40:22Nope.
40:24Not for an inadvertent slot deployment during cruise.
40:27Or an upset at high altitude.
40:31Hmm.
40:32Just giving them something to read is sort of like trying to learn to ride a bicycle if you've only read a manual.
40:40What's going on?
40:42When we did when we did?
40:43We did.
40:44With simulator training you get some hands-on training and you have a good idea of what to expect.
40:47He did not have that training.
40:48So, in fact, he was really a test pilot trying to get this airplane back under control after this uncommanded slat deployment.
41:04deployment was there something about the design of the aircraft that made it
41:11difficult to regain control this is the Airbus a300 here and the DC 10 here is
41:19our MD 11 when compared to other large passenger jets one design feature stands
41:26out look at the center of gravity so far aft most planes have their center of
41:33gravity further forward in the midsection that would make the MD 11 less stable
41:39the MD 11 was designed to increase fuel efficiency and to do that you move the
41:49center of gravity back fairly far aft the airplane becomes more pitch sensitive
41:55I found the airplane to be very maneuverable but some people would get a little bit behind it
42:05and you could end up in cases where the airplane would overshoot what you were expecting
42:10investigators conclude that the captain could have stabilized the oscillations
42:18sooner with faster less forceful control inputs
42:25but the design of the aircraft made that difficult to do
42:30in their final report NTSB investigators found that an unintended movement of the slat handle
42:42likely caused the slats to extend and the airplane to pitch up
42:49the probable cause is determined by the NTSB did not place any kind of blame or even talk about the flight
43:00crew actually causing this event this was a strict design issue that unfortunately the crew became a victim of
43:11the report also notes that many of the severely injured passengers either had their seatbelts unfastened or were standing in the aisle
43:24the flight attendants had made an announcement about seatbelts but as is often the case passengers may have ignored that announcement
43:36and that left many passengers vulnerable
43:43when you are in an airplane not just for takeoff not just for landing it is critical that you keep your seatbelt on
43:53you never know what can happen in flight
44:00you
44:02you