- 6 days ago
Air Crash Investigation Series S21E04 Grounded Boeing Max 8
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TVTranscript
00:01Just minutes after takeoff from Jakarta, Indonesia...
00:05Flying 610, I have no reliable altitude information. All instruments disagree.
00:09...pilots fight to control one of the world's newest airliners, the Boeing Max-8...
00:16They never really figured out what was going on.
00:19...and end up crashing into the Java Sea.
00:23This was a very serious accident.
00:25What does the tracking data show?
00:27Investigators follow an erratic flight path...
00:30They're off course. There are altitudes all over the place.
00:33...a history of maintenance issues...
00:35Did we have problems? I bet we did.
00:37...and learn about a treacherous piece of hidden software.
00:40Looks like the MCAS kicked in.
00:42What's that?
00:44...what they uncover shocks the world and grounds an entire fleet.
00:48The 737 MAX story will clearly be a watershed event in aviation history.
00:57That's the beginning.
01:01Overall, up.
01:03…egin-1037 Yard.
01:05Thank you, open my title.
01:06I'm only due to 7.
01:07...and 033.
01:08...and 033.
01:09It's just after 5 a.m. in Jakarta, Indonesia, as 181 passengers settle in for a short domestic flight.
01:39In the cockpit, 1st Officer Harvino performs pre-flight procedures.
01:51Fuel pumps are on.
01:53The captain on this flight is Bhavya Sunezha, who has more than 6,000 flying hours.
02:03The passengers are on board the latest version of the renowned Boeing 737.
02:09Known as the MAX 8, David Karbaugh is a former Boeing test pilot.
02:18The MAX is the fourth iteration of the 737, one of the most successful airliners ever.
02:25And it was basically born out of a need to improve efficiency and performance.
02:33The MAX 8 has quickly become Boeing's fastest-selling airplane, with more than 300 already in the skies and almost 5,000 in the order books.
02:45The one being used on today's flight was delivered to Lion Air two months ago.
02:50Lion 610, you are cleared to runway 25L via Sierra Charlie 1.
02:59Contact tower when you are in position.
03:03Lion 610, cleared to runway 25L via Sierra Charlie 1.
03:07All clear, no traffic, let's run before take-off.
03:13Flaps?
03:15Flaps 5, 5 indicated.
03:18Lion Air flight 610 is a 90-minute journey from Jakarta, over the Java Sea, to Banker Island.
03:29The low-cost airline operates hundreds of these short flights every day.
03:37Indonesia is the fourth most populous country in the world.
03:40And with 17,000 islands, you've got to have an easy way to do short-range transportation to get to those places.
03:50And the MAX is the ideal airplane for that kind of operation.
03:56Lion 610, cleared for take-off.
03:58Runway 25, contact terminal Eastwind Airborne.
04:02Lion 610, cleared for take-off.
04:10At 6.20, the MAX 8 lifts off the runway at Jakarta.
04:31But immediately there's trouble.
04:34The captain's control yoke starts shaking.
04:38A warning that the plane is about to stall.
04:41Take-off config.
04:44Okay, but what?
04:46The pilots can't identify the source of the problem.
04:50They have no choice but to continue climbing.
04:55The passengers are unaware that the pilots are dealing with anything unusual.
05:04Lion 610, fly heading 248.
05:07Follow standard instrument departure.
05:10Lion 610, fly in the air 610.
05:12The air traffic controller has no idea that there's an issue in the cockpit.
05:22The pilots get a warning that their airspeed indicators do not agree.
05:26The airspeed disagree.
05:28What's going on?
05:30Should we request a return to Jakarta?
05:36Landing gear up.
05:40Lion 610, climb to flight level 270.
05:44Still unaware of any trouble, the controller instructs the crew to continue climbing to 27,000 feet.
05:57Altitude disagree.
05:57The first officer now notices that the altimeters also show conflicting readings.
06:05Knowledge altitude disagree.
06:08Lion 610.
06:10Confirm our current altitude, please.
06:14Lion 610, your present altitude is...
06:16900 feet.
06:18The pilots are getting conflicting data about their altitude and their airspeed.
06:30Captain Suneja expects his first officer to carry out the procedure for this situation.
06:35Okay, memory items, airspeed unreliable.
06:39Uh, what altitude should I request?
06:42Yeah, uh, request, uh, proceed.
06:48The situation is deteriorating quickly.
06:54Climbing above 1,000 feet, the pilots are still unsure of their airspeed.
06:59If they fly too slowly, the plane could stall and fall from the sky.
07:05Request clearance to any holding point.
07:08Captain Suneja wants to get the plane to a point where he can circle and solve the problem.
07:14Lion 610, request clearance to some holding point due to our current condition.
07:19Lion 610, what's the nature of your problem, please?
07:24We are experiencing a flight control problem.
07:27Lion 610.
07:29Lion 710, where's the...
07:35Where's the...
07:38Airspeed, airspeed?
07:40There's no airspeed unreliable.
07:42It's there.
07:45Got it.
07:48Autopilot, if engaged, disengaged.
07:52Not every failure is a major emergency.
07:55and checklists are designed to grade or evaluate the severity of a system failure.
08:03So pilots are trained to methodically go through each step by step.
08:09Auto, auto, look engaged. Disengaged.
08:12Disengaged.
08:16But the checklist isn't helping.
08:20Okay, okay.
08:22Now flying 5,000 feet above the sea, Captain Suneja struggles to keep the plane's nose up.
08:29Flight path vector may be unreliable.
08:319-6-1-0, turn right, heading 0-7-0 to avoid traffic ad.
08:36Set the pitch attitude.
08:39Roger, heading 0-7-0.
08:459-6-1-0, you're now descending.
08:48We're having flight control problems and are flying manually.
08:536-1-0, maintain heading 0-5-0.
08:59The cabin would have realized that the airplane was not climbing as normal
09:03and that it had leveled off and there was probably some up and down sensations.
09:08Captain Suneja has been fighting to keep the plane's nose from pitching downwards.
09:17Please, take control for a moment.
09:19He now assigns that task to his first officer.
09:22I have control.
09:24So he can troubleshoot the problem himself.
09:27Oh, it's very...
09:29The first officer is also having difficulty keeping the aircraft level.
09:36There was a wide variety of problems that they had to sort out.
09:42And the first thing was what's common between all of these failures
09:46because that's how you start to sort through the problems.
09:48Flight 610 is flying erratically over the Java Sea
09:55and becoming increasingly more difficult to control.
10:00The lives of everyone on board now depend on the pilots figuring out the problem.
10:06I don't know where we are.
10:08And getting the plane to the ground safely.
10:11Line 6-1-0, I have no reliable altitude information.
10:14All instruments disagree.
10:15Roger, line 6-1-0, no restrictions.
10:20When an aircraft declares an emergency,
10:22the controller's number one job is to provide assistance to that airplane.
10:27The controller allows Flight 610 to fly at any altitude the pilots choose.
10:33Please clear 3,000 above and below of traffic.
10:37Okay, will do.
10:38What altitude would you like?
10:405,000.
10:41It's diving.
10:42It's diving.
10:43It's okay.
10:43Flight 610 is now speeding towards the sea.
10:48And the pilots are out of options.
10:513,000 above and below.
10:54Fly up.
10:55Up.
10:56Up.
10:593,000 above and below.
11:10Line 6-1-0, control.
11:12Lion Air 6-1-0, control.
11:20CityLink 882, please hold on current position.
11:25Do you have visual on Lion 6-1-0, a Boeing 737 MAX 8?
11:31Negative.
11:32No other planes in sight.
11:3330 minutes after crashing into the Java Sea,
11:45the wreckage of Lion Air Flight 610 is located.
11:49There are no survivors.
11:53Relatives of the passengers are flown to Jakarta for trauma counseling.
11:57While they wait for the recovery of the bodies of their loved ones,
12:04investigators from Indonesia's accident investigation branch KNKT need to understand why one of the best-selling new aircrafts in the world fell from the sky.
12:14Okay, what does the tracking data show?
12:26Working with data from air traffic control,
12:29KNKT investigators focus on the flight path of Lion Air 610.
12:34From this data, we learned that this plane's altitude was fluctuating.
12:50It kept going up and down.
12:53We wanted to find out why the pilot couldn't keep the plane at a constant altitude.
12:57Investigators need to know if the controller can shed any light on the problems the crew was facing.
13:08They reported that they were having a control issue.
13:13Lion 6-1-0, what's the nature of your problem, please?
13:19We are experiencing a flight control problem.
13:22Lion 6-1-0?
13:24That's all he said.
13:25A flight control problem.
13:27Soon after that, they reported that their instruments were unreliable.
13:34Lion 6-1-0 have no reliable altitude information.
13:37All instruments disagree.
13:39Roger, Lion 6-1-0, no restrictions.
13:43That was about it.
13:47From the information we received from the air traffic controller,
13:53we didn't get the impression that the pilot was under pressure.
13:56The pilot's tone was normal.
14:00It didn't seem that he was stressed.
14:02The thing that was told is that they asked.
14:07Since the pilots of Flight 610 reported flight control problems and unreliable instruments,
14:13investigators wonder if recent maintenance records could explain what brought down the MAX 8 only 11 minutes after takeoff.
14:22This flight had some problems with control.
14:28At that point, we needed to learn more about the plane's maintenance history.
14:34The angle of attack sensor was replaced the day before.
14:36There are two angle of attack sensors on the 737 MAX 8.
14:44The sensors calculate the angle between the plane's wing and the oncoming air.
14:50Their data helps determine if the plane's wings are providing sufficient lift.
14:54It's a very important piece of information.
14:58The pilots need to have some kind of warning that they are approaching stall.
15:03And so the angle of attack sensor is what gives that.
15:07For several days, the left side sensor had been giving faulty readings.
15:11It was finally replaced before the plane flew from Bali to Jakarta, one day before the accident.
15:22Investigators interview the crew who flew the same plane just hours before the crash,
15:27to determine if there were any problems with the replacement sensor.
15:32Did we have problems?
15:34Well, we did.
15:34We conducted an interview with the crew of Flight 043.
15:42We learned from them that after takeoff, the crew was also having problems.
15:49What investigators hear next is chilling.
15:55The captain explains that when he lifted off from Bali,
15:59there were simultaneous warnings that his airspeed and altitude indicators had failed.
16:04A few seconds later, the MAX 8 stick shaker activated,
16:12indicating that a stall was imminent.
16:15Keep climbing.
16:16You're up.
16:18All the modern airliners have three sets of independently powered essential flight instruments,
16:26airspeed and altitude, and also the attitude of the airplane.
16:29If there is a discrepancy, you can determine which is providing inaccurate data.
16:36Your instruments are correct.
16:38You have control.
16:41The failure was on my side, so I hand it off.
16:44Flaps up.
16:48The captain adjusts his faulty instruments,
16:51so they display data from the first officer's side.
16:53The captain reports that the plane began a series of uncommanded dives.
17:05Use your trim.
17:08That's it.
17:08In order to keep the plane climbing at a constant angle,
17:15the pilots set the position of their horizontal stabilizer at take-off
17:19and make minor adjustments during the flight.
17:22That's called trim.
17:24Trim can either be adjusted by the autopilot or manually by the crew.
17:28But every time the first officer tries to trim the nose up,
17:34the automated system pushes it back down.
17:37The first officer is finding it almost impossible to keep the plane climbing.
17:43The trim system on a modern jet has to be very powerful.
17:48The trim, in many cases, is actually more powerful than the control column.
17:53For some reason, the MAX 8 stabilizer continues to move independently,
18:00pushing the plane's nose down despite the first officer's commands.
18:06Let's see what's in the book.
18:08When the automated system moves the stabilizer,
18:11it also spins a large wheel that's located between the two pilots.
18:16This tells them that the system is adjusting the trim on its own.
18:19When the captain bent down to look at the checklist manual
18:27to solve the problem during this flight,
18:30the third crew was the one notifying the pilot
18:32that the trim was moving abnormally.
18:37Runaway stabilizer.
18:39We switch this to cut out.
18:41The crew realizes the stabilizer's automatic trim system is malfunctioning.
18:46It's continually pushing the nose down.
18:51Disengaging the system resolves the issue.
18:55They cut out the trim switches.
18:57The system stopped doing nose down trim.
19:00Moving the switch to cut out pretty much solved.
19:03The investigators learned that the previous crew
19:06then did something astonishing.
19:07If they had decided to return and land in Denpasar,
19:22it would have taken only five to ten minutes,
19:25and they could have landed safely.
19:27But they decided to continue flying to Jakarta.
19:30Line air 43, we'll continue on to Jakarta.
19:36Following a near catastrophe,
19:38with unreliable instruments and the stick shaker blaring,
19:42the crew elected to continue the 90-minute flight to Jakarta.
19:48It surprised all of us that they continued the flight.
19:52The crew managed to make a safe landing at Jakarta
19:57and reported the problem to maintenance personnel.
20:01I reported the issue and filled out the flight maintenance log.
20:05If the airplane experience is an abnormal or an unusual system failure,
20:10it goes into the maintenance log.
20:14Air speed and altitude disagree,
20:16but not a word about the stabilizer problem.
20:19Investigators are surprised to learn
20:22that the captain of the previous flight
20:24said nothing about the out-of-control stabilizer
20:27or the action he took to correct it.
20:31Runaway stabilizer.
20:33Moving switches to cut out.
20:35The lives of the passengers and the crew that follows you
20:40is basically dependent on you filling out the paperwork correctly.
20:47Good morning.
20:49Good morning.
20:51They're done loading,
20:52so we should be able to get out of here on time today.
20:55A few hours later,
20:56the passengers and crew of Flight 610 boarded the aircraft
21:00with no knowledge or warning of the potential problems
21:04faced by the previous crew hours earlier.
21:07Fuel pumps?
21:09Fuel pumps are on.
21:11Did a repeat of the problem on this aircraft result in the deaths
21:17of the 181 passengers and 8 crew?
21:26It takes three days for search and rescue teams
21:30to lock on to the signal coming from the MAX 8's flight data recorder.
21:34Divers recover it from a depth of 115 feet.
21:37The recorder has preserved data from the accident flight
21:43and 18 previous flights,
21:45covering almost 1,800 different parameters.
21:49Master caution goes off as soon as they leave the ground,
21:54probably because airspeed and altitude don't agree.
21:58Stick shaker activates here.
22:04The data shows a repeat of the problem on the previous flight.
22:09Faulty readings caused by a discrepancy
22:12between the left and right angle of attack sensors.
22:15From the FDR data we received,
22:20we learned that this plane had faulty angle of attack readings
22:24that affected both flights similarly.
22:26Dua penerpangan ini sangat mirip.
22:29Left and right angle of attack values
22:32are off by 21 degrees for the entire flight.
22:36We suspected the new angle of attack sensor installed in Bali
22:43was either faulty
22:44or the installation process was done incorrectly.
22:50The mechanic who replaced the sensor
22:53before the flight from Bali to Jakarta
22:55failed to ensure it was calibrated,
22:58which resulted in faulty readings.
23:00There's a procedure that would have shown
23:03it was erroneous and that it was bad.
23:07They signed off that they did it.
23:09They could not have done it.
23:11On the MAX 8,
23:13the angle of attack sensor
23:14doesn't just measure the airplane's angle.
23:17Altitude disagree.
23:19It helps calculate precise airspeed and altitude.
23:24That explains why airspeed and altitude
23:28disagreed throughout the whole flight.
23:30The malfunctioning sensor on the captain's side
23:33resulted in a difference
23:34between the left and right side's speed
23:36and altitude displays.
23:39Then there's this.
23:41The data clearly shows
23:42that for every nose-up trim input,
23:45there was a corresponding automatic nose-down trim input.
23:50Sounds like what the crew of Flight 43 described.
23:53The data shows investigators
23:55that for some reason,
23:56the plane's automated trim system
23:58was repeatedly dropping the plane's nose
24:01while the pilots fought to lift it.
24:0726 separate nose-down commands.
24:11This doesn't look like a runaway stabilizer to me.
24:15Runaway stabilizer is a common malfunction
24:17of the trim system,
24:19usually resulting in one continuous
24:21uncommanded movement of the stabilizer.
24:28The NTSB brought a representative from Boeing
24:31to help us in our investigation.
24:33We asked them to explain why
24:35in both Flight 610 and 043,
24:38the same plane continued to pitch down.
24:40We're trying to understand these automatic inputs.
24:50Looks like the MCAS kicked in.
24:54What's that?
24:57Boeing points to an obscure automated system
25:01known as MCAS,
25:02the Maneuvering Characteristics Augmentation System.
25:07That's when we first learned about the MCAS.
25:12To understand what could have caused
25:14the crash of Flight 610,
25:17investigators need to go back seven years
25:19to 2011,
25:21when Boeing first announced
25:23the development of the MAX 8.
25:25The 737 MAX
25:28was basically born out of a need
25:31to improve the performance
25:34and sales of the 737.
25:38In 2010,
25:40Boeing's main competitor, Airbus,
25:43unveiled the A320neo,
25:46a fuel-efficient short-haul airplane.
25:49It was an immediate hit with airlines
25:51at a time of rising fuel costs.
25:55Boeing was caught by surprise.
25:58The A320neo
25:59was significantly more fuel-efficient.
26:03So, all of a sudden,
26:04they were faced with a dilemma.
26:06Do you design a new airplane,
26:08a four- or five-year project,
26:10or do you modify the existing 737?
26:16But there were problems
26:17with taking a plane
26:18that was designed in the 1960s
26:20and turning it into a fast
26:23and fuel-efficient aircraft.
26:25To improve the performance of the MAX,
26:29they decided to install
26:31more fuel-efficient, larger engines.
26:35The only way to make
26:37those larger engines fit
26:39was to slide them forward on the wings.
26:42The design engineers had a problem
26:44with the ground clearance from the engines.
26:47And on 737,
26:48you can't increase the size
26:49of the main landing gear
26:50because of the size of the wheel wells.
26:53It has to fit there.
26:54So, the only thing they could do
26:56was to move the engines
26:57further forward and up.
27:00That solved one problem,
27:02but created another.
27:04It caused the 737
27:06to pitch up at low speeds,
27:08particularly when it was already
27:10in a nose-up position,
27:11like during take-offs.
27:13So, they created software
27:16that would recognize
27:17the airplane approaching stall
27:19and artificially
27:21force the nose down.
27:24And, logically,
27:25they turned to the trim system
27:27to do that.
27:29And that's the problem
27:30you solved with MCAS?
27:31Yes, it made the MAX handle
27:32like any other 737.
27:35MCAS was designed
27:38for a very low-probability event.
27:42It's diving.
27:43It's diving.
27:44It's okay.
27:45How were they trained to respond?
27:47Well, they were.
27:48Not specifically.
27:50Fly up.
27:51Up.
27:51Up!
27:53Could Boeing's high-tech solution
27:55to a design problem
27:57have inadvertently put
27:59thousands of passengers
28:00around the world at risk?
28:06In order to eliminate
28:07the need for costly pilot training,
28:10Boeing had to convince authorities
28:12that the MAX 8
28:13handled the same way
28:14as all previous 737s.
28:17Different handling characteristics
28:19will automatically require
28:21time in the simulator
28:23and extra training.
28:25Boeing argued that
28:26since MCAS operated
28:28in the background
28:29without the need
28:30for any pilot input,
28:31it didn't affect
28:32the airplane's handling.
28:35It's not a word
28:37about MCAS here.
28:39Boeing never included mention
28:40of MCAS
28:41in the flight control manuals.
28:45They argued that
28:46since the system
28:47was not under control
28:48of the crew,
28:49it should not be included.
28:52It's like the system
28:53doesn't even exist.
28:56Boeing thinks
28:59that it's an automatic system
29:00for safety purposes
29:01and has nothing to do
29:03with pilot operation.
29:07According to Boeing,
29:08the MCAS software
29:09would automatically
29:10move the plane's stabilizer
29:12to push the plane's nose down
29:14if it started to pitch up
29:16under very specific circumstances.
29:21It only kicks in
29:22when these three conditions
29:23are met.
29:26Boeing explains
29:27that MCAS only activates
29:29when it senses
29:30that the angle
29:30of attack
29:31is excessive
29:32when the autopilot
29:35is off
29:35and when the flaps
29:38are retracted.
29:39An extremely rare combination.
29:42Professional pilots
29:43don't typically
29:45stall airplanes,
29:46so the likelihood
29:48of an MCAS activation
29:50was thought
29:51to be extremely low.
29:52This is the data
29:55of both flights.
29:56Tragically,
29:57the data shows
29:58that because of
29:59the faulty maintenance
30:00on the angle
30:00of attack sensor,
30:02flight 610
30:03ended up meeting
30:04all three conditions.
30:09The series of problems
30:11occurred
30:11when the left angle
30:12of attack sensor
30:13was replaced in Bali.
30:19Investigators
30:20dig deeper
30:20into the data
30:21and discover
30:22the MCAS system
30:23had no fail-safe.
30:29The MCAS
30:29installed in the plane
30:30relied on only
30:31one sensor.
30:35MCAS only took data
30:36from one angle
30:37of attack sensor,
30:39not both.
30:41Most protection systems
30:43are designed
30:44with redundancies.
30:45Your instruments
30:46are correct.
30:47You have control.
30:48So a single failure
30:49doesn't result
30:50in catastrophe.
30:51flaps up.
30:53What Boeing did
30:55not adequately do
30:56was assess
30:58all of the other
30:59failures that
30:59that single component
31:01would have.
31:02The faulty angle
31:04of attack sensor
31:05wrongly showed
31:06the plane
31:07pitching up steeply.
31:09The autopilot
31:09was disengaged
31:10for the entire flight.
31:11And then right here
31:14they retract the flaps.
31:16Exactly the same
31:18as the previous flight.
31:23That's when
31:24MCAS kicks in
31:26and starts pushing
31:29the nose down.
31:31up to this point
31:33up to this point
31:33the crew
31:34only had
31:35a minor
31:35instrument problem.
31:38By raising
31:39the flaps
31:40the pilots
31:41unknowingly
31:42triggered
31:42a much more
31:43serious problem.
31:48We assume
31:49the pilots
31:49would know
31:49how to respond.
31:52Boeing made
31:53the assumption
31:54that pilots
31:54would respond
31:55to the uncommanded
31:56MCAS inputs
31:57by disengaging
31:58the automatic trim.
32:01The Boeing
32:02assumptions
32:03were that
32:03the pilots
32:04would instantly
32:04recognize
32:05the inadvertent
32:07MCAS activation
32:08and treat it
32:10within three seconds.
32:13Investigators
32:14examined the flight
32:14data of the
32:15previous Lion Air
32:16flight to see
32:17how that crew
32:18reacted to
32:19the MCAS activation.
32:22The first
32:22MCAS input
32:23on Flight 43
32:25is here.
32:27The captain
32:27pulls
32:28back on his
32:29control column
32:29and applies
32:30manual trim
32:31then fights
32:32against
32:33the MCAS
32:34for three minutes
32:35and 40 seconds
32:35before hitting
32:36a cutout switch.
32:38I think the
32:38assumption
32:39that they were
32:40going to recognize
32:41and act
32:42within three seconds
32:43was very optimistic
32:45if not unrealistic.
32:49Lion 610
32:51I have no reliable
32:52altitude information
32:53all instruments
32:54disagree.
32:55Unlike the
32:56previous crew
32:57the pilots
32:58of Flight 610
32:59struggled with
33:00the problem
33:00for more than
33:01ten minutes
33:02and never made
33:06the connection
33:06to a runaway
33:07stabilizer.
33:14Investigators
33:15need to understand
33:16why two crews
33:17facing an identical
33:19problem
33:19reacted so
33:21differently.
33:26Investigators struggle
33:28to understand
33:28why the pilots
33:29of Lion Air
33:30Flight 610
33:31lost control
33:32of the aircraft.
33:34After nearly three months
33:35of searching
33:36the ocean floor
33:37the cockpit voice
33:38recorder
33:39is finally recovered
33:40and taken for analysis.
33:41The CVR was the key
33:46to our investigation.
33:48Together with
33:49the FDR data
33:49the CVR
33:51could reveal
33:51all the mystery
33:52in our investigation.
33:57Lion 610
33:58cleared for takeoff.
34:00Investigators
34:01hope the recording
34:02will help
34:03to explain
34:03why the crew
34:04of Flight 610
34:05couldn't identify
34:06the problem
34:07and take
34:08corrective action
34:09to fix it.
34:10Rotate.
34:10the faulty
34:20angle of attack
34:20sensor
34:21triggers a series
34:22of warnings
34:22as soon as
34:23the plane lifts off.
34:27Airspeed disagree
34:28what's going on?
34:32Should we request
34:33a return to Jakarta?
34:35Landing gear up.
34:36after takeoff
34:42the MCAS system
34:43was activated
34:44and their plane
34:45started to pitch down.
34:48The captain
34:49has noticed
34:49that the plane's stabilizer
34:51is now automatically
34:52trimming the nose down
34:53and does what
34:54Boeing assumed
34:55he would.
34:57He pulls back
34:58on the control column
34:59and uses manual trim
35:01to counteract
35:02the computerized inputs.
35:05Okay.
35:06Boeing was right
35:07about that.
35:08But the captain
35:09never mentions
35:10the trim problem.
35:12He and his
35:13first officer
35:14are focused
35:14entirely
35:15on their faulty
35:16airspeed
35:17and altitude readings.
35:18Where is the
35:19airspeed, airspeed?
35:22There's no
35:23airspeed unreliable.
35:24It's there.
35:26Got it.
35:29This is where
35:30we found
35:30significant differences
35:32between flight
35:33043
35:33and 610.
35:36It takes
35:37first officer
35:37Harvino
35:38nearly two minutes
35:39to locate
35:40the appropriate
35:40checklist
35:41for mismatched
35:42airspeed.
35:43I think the
35:43first officer
35:44was pretty well
35:44task saturated
35:45and one of the
35:46things that
35:47task saturation
35:48does in humans
35:49it limits
35:50our ability
35:51to communicate.
35:52We don't hear
35:52well and we
35:53don't verbalize
35:54things very well.
35:56Pops up
35:57four degrees
35:57and 75%
35:58at one.
36:00There it is.
36:01When the
36:02automated trim
36:03system pushes
36:04the nose down
36:05the large wheel
36:06makes a
36:07characteristic sound.
36:10When the
36:11trim wheel moves
36:11it makes a
36:12sound like
36:13a freight train.
36:15It's meant
36:15to be noticeable
36:16following a
36:18reliable
36:19attitude
36:20and one
36:22ground speed
36:23check.
36:26They still
36:27don't notice it.
36:30Wrong about that.
36:31He didn't put it
36:32together that
36:33every time he
36:34trimmed up
36:35the MKS system
36:36was trimming it
36:37back down.
36:3934 times.
36:41He applies
36:41nose up trim
36:4234 times
36:44and doesn't think
36:45to wonder
36:45why.
36:49They did not
36:50recognize
36:50the problem
36:52and take the
36:53corrective action
36:54Boeing predicted
36:55they would.
36:56In this particular
36:57case,
36:58Boeing made
36:58assumptions
36:59about design
37:00and pilot
37:02experience
37:03and training
37:03that didn't
37:05add up.
37:06investigators
37:14now hear
37:15another
37:15crucial
37:16difference
37:16between
37:17flight 610
37:18and the
37:18previous
37:19flight.
37:20That's it.
37:21Please take
37:22control.
37:23Not a word
37:24about the fact
37:25that he's had
37:25to make
37:26more than
37:2630 trim
37:27inputs.
37:31I think
37:31the captain
37:32was very
37:33frustrated
37:33with the
37:34first officer.
37:37And I'm
37:38sure he
37:39didn't really
37:39want to hand
37:40it over
37:40to the
37:41first officer
37:41but he
37:43felt that
37:43he needed
37:44to in order
37:44to figure
37:45out what
37:45was going
37:46on with
37:46the checklist.
37:47But because
37:48there's no
37:49mention of
37:49MCAS in
37:50the manual,
37:51there isn't
37:52a checklist
37:52for the
37:53crew to
37:53follow.
37:55It's diving.
37:56It's diving.
37:57With no
37:57warning from
37:58the captain
37:58about the
37:59need for
37:59repeated
38:00nose up
38:00trim,
38:01the first
38:02officer
38:02quickly becomes
38:03overwhelmed.
38:04Sadly,
38:06this first
38:07officer was
38:08pretty well
38:08overwhelmed
38:09and as
38:10the system
38:11trimmed the
38:11nose down,
38:13he was not
38:13nearly aggressive
38:14enough in
38:15responding to
38:16that.
38:19In flight
38:20610,
38:21the pilot
38:21didn't deactivate
38:22the automatic
38:23trim and the
38:24plane's nose
38:25kept coming
38:25down because
38:26of the MCAS
38:27and it didn't
38:28stop until
38:29the plane
38:29crashed.
38:31One minute
38:32after taking
38:33control,
38:34the first
38:34officer watches
38:35helplessly as
38:36the plane
38:36plunges towards
38:37the Java
38:38Sea.
38:42KNKT
38:43investigators
38:44discover that
38:44Boeing's
38:45assumptions of
38:46how pilots
38:46would recognize
38:47and overcome
38:48an uncommanded
38:49nose down
38:50trim on the
38:51MAX 8 were
38:52fatally
38:52flawed.
38:53they sure
39:01didn't act
39:01the way
39:02Boeing said
39:02they would.
39:04Here it
39:05is.
39:06Without
39:07requiring
39:08exceptional
39:08skill or
39:09strength.
39:11Investigators
39:12soon learn
39:13why Boeing's
39:14assumptions about
39:15how pilots
39:15would react
39:16were so wrong.
39:18To certify the
39:19MAX 8,
39:20Boeing assured
39:21the FAA
39:21that an
39:22average flight
39:23crew would
39:24be able to
39:24override the
39:25MCAS system.
39:27So were
39:27these guys
39:28average?
39:31Captain
39:31passed all
39:32his checks.
39:34Looks like a
39:35competent pilot.
39:40This guy
39:41is a whole
39:43different story.
39:45Investigators
39:46are surprised
39:47by the first
39:47officer's
39:48background.
39:48The first
39:50officer on
39:51Lion Air
39:51Flight 610
39:52had had
39:53challenges in
39:53training.
39:54He had
39:55trouble staying
39:55up with the
39:56airplane,
39:56understanding
39:57the complexities.
39:58His manual
39:59flying skills
40:00were not
40:01optimum and
40:02he required
40:03additional
40:03training.
40:05It's diving.
40:06It's diving.
40:06It's okay.
40:07Flight 610
40:08proved that
40:09Boeing was wrong
40:10about how
40:11pilots would
40:11react to an
40:12MCAS failure.
40:14Fire.
40:14Up.
40:15Up.
40:18They never
40:20really figured
40:21it out and
40:22then the
40:24captain gave
40:24control to
40:25someone whose
40:26manual flying
40:27skills were not
40:28going to save
40:29the day.
40:30As a result of
40:31the accident,
40:32Boeing issues
40:33new guidelines
40:34for MAX 8
40:35pilots, informing
40:36them about
40:36MCAS and
40:38detailing the
40:38procedures to
40:39follow in the
40:40event it triggers
40:41an uncommanded
40:42nose down.
40:43The bulletin
40:45advises pilots
40:45to apply manual
40:47trim and to
40:48move the
40:48stabilizer trim
40:49switches to
40:50cut out.
40:51This was a
40:52reinforcement to
40:53the pilots that
40:54says there is a
40:55system on the
40:56airplane that
40:57can move the
40:58trim.
40:59If it does so,
41:01treat it as a
41:01runaway stabilizer.
41:04Hey,
41:05is there any
41:06TV on?
41:06Our breaking
41:13news.
41:14An Ethiopian
41:15airlines has
41:16crashed shortly
41:17after takeoff
41:17from Addis
41:18Ababa.
41:19The belief
41:20that Boeing's
41:21advisory would
41:22prevent another
41:22similar accident
41:23is shattered
41:24four months
41:25later when
41:26another MAX 8
41:27crashes.
41:30Flight tracking
41:31data shows that
41:32Ethiopian airlines
41:34flight 302's
41:35altitude fluctuates.
41:36throughout the
41:37flight.
41:39There's immediate
41:40speculation that
41:41once again,
41:42Boeing's MCAS
41:43software is to
41:44blame.
41:45In both
41:46accidents, the
41:47MCAS activated,
41:49causing this
41:50nose down trim
41:51situation to
41:52occur repeatedly.
41:54And in both
41:55cases, the crews
41:56let the airplane
41:57accelerate far,
41:58far greater speed
41:59than it should
42:00have been.
42:00Put those two
42:01together and
42:02controllability of
42:03the airplane was
42:03lost.
42:03This time, the
42:06pilots knew about
42:07MCAS and what
42:09to do in case
42:09it activated,
42:11yet they still
42:12couldn't control
42:13the airplane.
42:14Boeing realized,
42:15well, if this
42:16crew can't handle
42:18it, then other
42:19crews won't.
42:21In spite of the
42:23FAA's assurance
42:24that the MAX 8
42:25is airworthy,
42:26regulators around
42:27the world ground
42:28the global MAX 8
42:29fleet until the
42:31problem with MCAS
42:32is fixed.
42:35The main thing
42:36in our mind was
42:36we worried that
42:37all of the Boeing
42:38737 MAX 8s that
42:40are currently flying
42:41all over the world
42:41might have the
42:42potential to suffer
42:43the same catastrophe.
42:46The FAA
42:48eventually follows
42:49suit.
42:51Our concern isn't
42:53with the mistakes
42:53that were made.
42:54A U.S.
42:54congressional
42:55investigation
42:56determines that
42:56Boeing made faulty
42:58technical assumptions
42:59and errors in judgment
43:00which led to these
43:01accidents.
43:02I didn't know
43:03about this.
43:04It's unacceptable.
43:06Boeing insists
43:07it's learned
43:08from these incidents
43:09and is determined
43:10to make the MAX 8
43:11safe and regain
43:13public trust.
43:14Boeing has committed
43:16to making it easier
43:17for pilots
43:18to override
43:19the MCAS system.
43:23Once that override
43:24is activated,
43:26the system
43:27will not continue
43:28to re-engage.
43:32And they're developing
43:34a training program
43:36to familiarize pilots
43:37with MCAS.
43:43The 737 MAX story
43:46will change forever
43:48how airplanes
43:49are certified.
43:50And the 737 MAX
43:51will clearly be
43:53a watershed event
43:54in aviation history.
43:55Those
44:08lectures
44:08to punkt
44:12to識
44:14the
44:16seconds
44:19and
44:19to
44:20in
44:21in
44:22in
44:23in
44:24in
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