Air Disasters (2022) Season 17 Episode 6: Terror Over Michigan
Investigators must pull off a risky test flight to see if the pilots of a heroic emergency landing are hiding a secret.
#documentary #historical
Investigators must pull off a risky test flight to see if the pilots of a heroic emergency landing are hiding a secret.
#documentary #historical
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TVTranscript
00:00We're going over!
00:04A Boeing 727 spirals out of control over Michigan.
00:08You're watching the world spinning outside the window.
00:12This would be sheer, stark terror.
00:14Airspeed is 320, 350.
00:17Come on!
00:18Come on!
00:19No, no, no!
00:21Investigators track down pieces of debris.
00:25Spot number seven.
00:30Broken in two.
00:32And interview fellow pilots.
00:35Off the record.
00:36Off the record.
00:37They even risk their own lives.
00:40Okay, test number nine.
00:43To find out what caused TWA flight 841's uncontrollable plunge.
00:49You feel that?
00:50It was insane.
01:10My hands are still shaking.
01:25Forty-four-year-old Captain Harvey Hoot Gibson has just returned from the most harrowing
01:29flight of his life.
01:31Tell me what happened.
01:34A representative from the Federal Aviation Administration takes his statement.
01:39We were cruising over Michigan.
01:53That sure is a strong headwind.
01:58Captain Gibson is a trained stunt pilot who has a clean 16-year record with Transworld
02:03Airlines.
02:04Do a ground speed check, will you?
02:09Sure thing, Hoot.
02:12First Officer Scott Kennedy has been flying with TWA for 13 years.
02:17We're good to go up anytime you want, Hoot.
02:22Flight Engineer Gary Banks is an Air Force veteran who's been with TWA for the last 10
02:28years.
02:29The crew of flight 841 had just the right kind of experience you would want for a 727
02:35crew.
02:36Center, TWA 841, we'd like to try flight level 390.
02:41Roger, TWA 841, climb and maintain flight level 390.
02:51They were bucking 100 knots of wind on their nose, so he was looking for better winds up
02:58higher.
02:59The higher you go, you essentially go faster through the thinner air, and that will hopefully
03:05get you a better ground speed.
03:19I can take that off your hands.
03:2027-year-old Mark Mosisky is today's lead flight attendant.
03:27He and three other attendants look after the 82 passengers on board.
03:35It was an evening flight.
03:36I was leaving JFK.
03:38It was the first time I had flown with this cockpit crew.
03:43Everything was absolutely smooth.
03:45They're flying the narrow-body Boeing 727 aircraft.
03:50The 727 was massively overbuilt.
03:53It was a very sturdy airplane.
03:55It was like driving a sports car or a fighter plane.
03:58It was very light on the controls.
04:01It had that feeling that you could just put it wherever you wanted it.
04:06After a 45-minute delay in New York, the flight to Minneapolis will take about three and a
04:10half hours.
04:18They programmed 39,000 feet and got right up there.
04:22And sure enough, they were gaining speed.
04:25They were probably going to cut 10 to 15 minutes off their in-route time.
04:31I'll do another ground speed check.
04:44Power settings adjusted.
04:45Everything looks good.
04:49After meal service, Mosisky takes a moment to eat his own meal.
04:53I sat in my jump seat.
04:57Very shortly, however, there was a very abrupt buffeting of the aircraft.
05:04It wasn't turbulence.
05:06What the heck?
05:09The captain noticed something was strange.
05:11The wing had started to drop and the autopilot was compensating for that.
05:18I got control.
05:19Disengaging the autopilot was the right thing to do at that time.
05:23That's the first thing you think of.
05:24There's something wrong with the autopilot.
05:26What's going on?
05:29Without any warning, the plane banks hard to the right.
05:34Airspeed 240.
05:35Come on.
05:36Level up.
05:37But if the plane still doesn't respond, then you're thinking there's something wrong with
05:44the airplane.
05:48The plane just kept rolling right, and it started rattling really hard, too.
05:53I would be trying the rudder, and if that's not doing the jobs, I'd start trying to fly
05:59with the engines, but 727, the engines are all clustered together in the back.
06:04That probably wouldn't help you much.
06:06So this would be pure stark terror.
06:08Shutting the throttles.
06:10The captain tries to slow the plane to regain control, but the aircraft isn't responding.
06:21Get him up.
06:29Get him up.
06:30Desperate to slow the plane, Gibson deploys the speed brakes.
06:37Speed brakes are flight control surfaces that increase drag and decrease speed.
06:43You're going to put those out to try and slow yourself down, because really bad things are
06:50going to start happening soon if you keep accelerating.
06:53Come on.
06:55Come on.
06:57But deploying the speed brakes proves useless.
07:00I got out from my jump seat to see if perhaps the engine was on fire, and I never made it.
07:13We're going over.
07:20High above Saginaw, Michigan, the Boeing 727 drops into an uncontrolled dive and spins
07:28upside down.
07:30Something was extremely wrong.
07:33There seemed to be no control of the airplane.
07:35People were just absolutely terrified.
07:40I sincerely didn't think that we had wings left on the airplane.
07:44TWA 841, this is center.
07:54TWA 841, center.
08:01Jesus.
08:04Something is seriously wrong.
08:09You would have your hands full of airplane.
08:11You're watching the world spinning outside the window.
08:14You're being pressed by G-forces.
08:16It also must have been insanely noisy.
08:18It would have been very difficult to try and troubleshoot the problem.
08:21TWA 841, do you read me?
08:25The controllers watch helplessly as TWA 841 plummets toward the ground.
08:32Once the nose comes down on an airliner, they want to pick up speed in a hurry if you point
08:37it at the ground.
08:40I kept clenching my jaws and biting my teeth to keep blood in my head.
08:45The G-forces were so extreme, I felt I was going to pass out.
08:51The blood is literally being drained out of your head, and you will first lose your vision.
08:58That's called graying out.
09:00And then the next thing is you black out, which is where you lose consciousness, because
09:04your heart just can't pump the blood up to your brain against all that force of gravity.
09:12Airspeed is 320, 350.
09:16I can't.
09:19I can't.
09:22I can't.
09:24TWA 841 is spiraling toward the earth at a rate of 540 feet per second.
09:31To feel six Gs, the only people that would experience that would be military pilots.
09:35You're going to feel an incredible weight on you and every part of you.
09:39And whatever position your body is in, your head or your arms, they're going to stay that way.
09:44So you're not going to be able to move.
09:50I could see ground lights, and I knew that we were approaching the ground very quickly.
09:55At that point, you go from abject terror into almost acceptance.
10:00No, no, no!
10:03Come on, baby! Pull up!
10:15We were falling so fast.
10:18Captain Hoot Gibson recounts his recent nightmare piloting TWA Flight 841 over Michigan.
10:26Airspeed is 390.
10:29But Ibsen isn't giving up.
10:31Come on, baby! Pull up!
10:33He has an idea.
10:35Put the gear down!
10:38If nothing else will slow you down, the gear will slow you down.
10:42And hopefully, the plane holds together.
10:58That's it! That's it, baby!
11:08What saved them was putting the gear down,
11:10because otherwise they would have been a big smoking crater in a matter of seconds.
11:18We're pitching up 30 degrees.
11:24Now suddenly we were climbing.
11:26It was like coming out of the bottom of a roller coaster.
11:30You would feel like you were being crushed.
11:32You would feel like you were being crushed.
11:34The average person would feel like they weighed 900 pounds.
11:39Scott, give me altitude!
11:41Gary, pitch and airspeed!
11:445,200 feet. Jesus, which way is up?
11:52Moon!
11:55It's pitch black, and you've just been spiraling down towards the Earth.
12:01And you're probably disoriented.
12:03He sees the moon, and that's up.
12:06You can sort the rest out later, but get away from the ground.
12:12TWA 841 has come within seconds of impact,
12:15and now climbs back toward the night sky.
12:21Airspeed is 160.
12:25Though the pilots are flying again, they are not out of danger.
12:30The steep climb is physically demanding, and the crew struggles to maintain focus.
12:3810,500. 11,000.
12:44That's it. That's it, Hoot.
12:46Leveling 110.
12:52This is your captain speaking.
12:54As you've noticed, we've had a bit of a problem,
12:57but everything seems to be under control.
13:06We lost system A hydraulics.
13:09Fluids are down. Pressure is down.
13:12As the crew recovers from the terrifying incident, they assess damage to the aircraft.
13:18We've got a flag for the lower yaw damper.
13:23A deafening rattle makes a tense situation worse.
13:28Okay, I'm going to fly the airplane.
13:30You guys start running the emergencies.
13:34He was a good captain.
13:35He had them diagnose the problem while he flew the airplane,
13:38knowing that you can't do both effectively.
13:42Turn pump emergency switches to depressurize and check quantity.
13:46The fluid is zero. It's all gone.
13:49With a damaged hydraulic system, the aircraft is severely impaired.
13:53Okay, we've got to land. Detroit is our best option.
13:56Okay.
14:00We're 60 miles out.
14:03When they decided to divert, they selected Detroit with reasonable weather, long runways.
14:08It's a developed airport with crash fire rescue.
14:11Center 841.
14:13Go ahead, CWA 841.
14:15Okay, listen. We had a problem. We lost about 20,000 feet.
14:19We had a problem. We lost about 20,000 feet.
14:23We need vectors to Detroit.
14:2545 miles for Detroit now.
14:27If you'd like to come left, heading 160, vectors to Detroit.
14:33Okay. Turn left 160. TWA 841.
14:43Remove your glasses, earrings, and anything else that might be sharp.
14:49Place anything soft in your lap to cushion the impact.
14:5430 miles from the airport, flight attendants prepare the cabin for an emergency landing.
15:00Passengers were amazingly quiet. I mean, they looked at us for complete direction.
15:0515 miles from Detroit now.
15:07Nice and easy. Give me flaps 15.
15:10Unaware of the extent of the damage, Gibson tests the aircraft's controllability.
15:16Flaps 15.
15:18Whoa, whoa, whoa. Retract the flaps.
15:22Extending the flaps causes the plane to roll sharply to the left.
15:27You are going to land without flaps at this point, which means you are going to go very fast.
15:34Much faster than you would ever land this airplane.
15:37Going fast. There's no other way.
15:48This is going to be our only approach.
15:51With ruptured hydraulics and a compromised plane,
15:55the pilots of TWA 841 have only one shot at landing at Detroit Airport.
16:04Landing checklist complete. Coming through 200 feet.
16:09I was pretty convinced that we'd probably be scraping down the runway.
16:15Lots of sparks and flames.
16:1850.
16:2140.
16:2430.
16:2840.
16:3030.
16:3240.
16:3430.
16:3640.
16:3840.
16:43Brace.
16:49220 knots in this case. Just an insane rate of speed for a landing.
16:56Reverse thrust.
16:58Come on. Come on. Stop.
17:08Stop.
17:24Let's get these passengers off the plane.
17:27He's just put this badly damaged airplane down at about 90 knots faster than a normal landing speed.
17:38This guy was good. He was really good.
17:48It's unbelievable.
17:52What the heck went so wrong with that plane?
17:55I have the faintest idea.
18:03Investigators from the National Transportation Safety Board arrive in Detroit to determine what went wrong with TWA Flight 841.
18:16They look in good shape. Let's get the data on these.
18:19The flight data recorder and cockpit voice recorder are removed from the aircraft and sent for analysis.
18:27Let's check that out.
18:38Slat number seven is missing.
18:41Slat number seven is missing.
18:47Slats and flaps are control surfaces on the leading and trailing edges of the wings.
18:53They are always extended in tandem.
18:58Both devices increase lift at low speeds during takeoff and landing.
19:03It's pretty banged up.
19:06Investigators wonder why the slat came off.
19:12The hydraulics lines are ruptured too.
19:15Logical outcome for a slat tearing off.
19:20Looks like the actuator for the slat is damaged.
19:26The actuator is damaged.
19:29The actuator is part of the mechanism that pushes a piston to unlock the slat, allowing it to either deploy or retract.
19:38Let's get the actuator off the wings so we can get a better look at it.
19:46One of the interesting remnants of this inspection was the number seven slat actuator.
19:59Look at how it's broken.
20:08There are no scrape marks inside either.
20:11Investigators uncover an important clue.
20:15Slat came off in an extended position.
20:18Number seven slat actuator had broken.
20:22The piston inside it was gone.
20:25And they could recognize from looking at the opening of the fracture that the piston had been in the deployed position.
20:35A slat should never deploy at cruising speed.
20:41Maybe this slat extended by accident.
20:43Maybe this slat extended by accident.
20:46The only way to know for sure is to test the hydraulic system.
20:51For the slat to have been deployed uncommanded required a failure of the hydraulic system and a failure of the locking mechanism.
21:05I'll start with flaps two.
21:14Flaps 15.
21:17Flaps 15.
21:29Looks good. Next flaps 20.
21:33Flaps 20.
21:36Investigators run through every flap setting possible.
21:40Investigators run through every flap setting possible.
21:47All right, let's wrap it up.
21:49Everything's working fine.
21:51The functional test demonstrated that the hydraulic system worked.
21:55It did not cause an uncommanded slat deployment.
22:00Here's what we got from Boeing.
22:02Did the locking mechanism on the 727's wing somehow fail, releasing the slat?
22:09For a slat to unlock accidentally, the pin inside the actuator must be subjected to more than 70 G's of force.
22:1770 G's?
22:21There's no way the locking mechanism experienced that level of stress.
22:26A 70 G pull through by an aircraft just doesn't happen.
22:32The investigators were faced with a serious challenge of where to go next.
22:46Take a look.
22:49Investigators get a break when debris from Flight 841 is recovered seven miles north of Saginaw, Michigan.
22:58Slat number seven.
23:02Broken in two.
23:06Look at this.
23:10Here's the number seven slat's T-bolt.
23:15T-bolts are part of the slat track assemblies.
23:18The number seven slat T-bolt was attached to the inboard side of the slat, which deploys and retracts inside the wing.
23:27Let's send this to the lab.
23:29They hope metallurgical analysis will offer some clues.
23:33But an important question remains.
23:36Why did the slat extend?
23:40There's only one other way a slat could extend.
23:45Through pilot action.
23:50This was something that had been probably commanded in the cockpit.
23:55And it was distressing to everybody.
23:59Why would a pilot do something as dangerous as extending the slats at cruising speed?
24:09Can't find anything in the captain's statements about slats and flaps.
24:14Investigators pore over the crew's statements.
24:17They look for any mention that flaps and slats were deployed mid-flight.
24:23There's nothing from the other crew members either.
24:29I have an idea.
24:39Thanks for meeting with me.
24:41The NTSB consults with pilots to determine whether or not the slats were deployed mid-flight.
24:47They ask pilots to learn why they might extend a flap or slat mid-flight.
24:53Off the record.
24:54Off the record.
24:56Flaps, yes.
24:58Slats, no.
25:00Flaps?
25:02Investigators learn of an unauthorized procedure used by some pilots that could save fuel and potentially time.
25:11I thought that wasn't possible.
25:14It is.
25:15If you pop the breaker.
25:21The procedure involves deploying trailing edge flaps by two degrees.
25:27By pulling the circuit breaker for the slats, the flaps can be extended while preventing the slats from automatically deploying at the same time.
25:38It's one of those things everybody knows about, but I've never heard anyone ever admit to it.
25:46Ready?
25:50Investigators turn to the cockpit voice recorder for evidence that TWA 841's pilots used the unauthorized procedure.
26:01Let's get these passengers off the plane.
26:04Hang on.
26:06Did you start the tape at the beginning?
26:11Yes, it's fully rewound.
26:12Play it again.
26:14Just to be sure.
26:27Let's get these passengers off the plane.
26:34The plane's already on the ground.
26:37This can only point to one thing.
26:39This can only point to one thing.
26:43The pilots erased the tape.
26:53The CVR contained no information whatsoever, which was unfortunate to say the least.
27:09We have to talk to Gibson.
27:13The team flies to California to question Captain Gibson in person.
27:23The safety board conducts public hearings.
27:27They question the flight crew.
27:31I told him I thought it was, I said, I said the airplane's going to roll.
27:35The airplane's going to roll.
27:42The captain admits to routinely erasing the cockpit voice recorder after every flight, even though that isn't a step on any checklist.
27:54Do you usually erase the recorder?
27:57I usually do, yes.
28:06It's just not credible that after the crew had been through what they did, where they came within seconds of dying, that the captain would erase the CVR as a manner of habit or routine.
28:25Something's wrong here.
28:27Captain Gibson's vague explanation doesn't sit well with investigators.
28:32Given what happened, they suspect the flight crew attempted the unsanctioned procedure and then tried to cover up their actions.
28:43The only reason he would erase the CVR was to keep information from what he knew would be an investigation.
28:54Investigators believed he had something to hide.
29:02Maybe the FDR data can tell us more.
29:06The team studies TWA 841's flight data to uncover any evidence that the crew attempted a mid-flight flap extension.
29:21Wow, it sure picks up speed.
29:23Wow, it sure picks up speed.
29:26In 44 seconds, the plane goes from 229 knots to over 400 knots.
29:35That's incredible.
29:40Look at this.
29:42Close inspection of the data gives the team an important clue.
29:46That's odd. Are those oscillations?
29:49Yes, in the G-trace.
29:50The G-trace shows the level of G-forces being put on the plane throughout the flight.
29:57Let's get this section blown up.
30:00The G-trace showed the G-forces in the airplane were sort of increasing and then decreasing in a certain rhythmic pattern.
30:07Very, very unusual.
30:11The oscillations start at 39,000 feet just before the upset.
30:18They show up 1, 2, 3, 13 seconds before the roll starts.
30:24It looks like the plane was really bouncing around.
30:31What the heck?
30:33The data tells investigators that the plane was moving erratically for 13 seconds before the first roll.
30:42Here's a thought.
30:44Here's a thought.
30:48What if there's a flap and slap configuration that could cause the vibration?
30:55Let's find out.
31:05We've reached 39,000 feet.
31:08NTSB investigators take an unprecedented risk in an attempt to replicate the oscillations recorded on TWA 841's G-trace.
31:20Okay, we've got more than a dozen configurations and maneuvers.
31:25They run a test flight to determine if these anomalies resulted from a mid-flight slap extension.
31:32Conducting a flight test would enable them to perform maneuvers that could be compared to what the flight data recorder recorded on 841.
31:42229 knots.
31:44Okay, test number one.
31:47Start by popping the breaker.
31:52Okay, slats are retracted.
31:55Ready?
31:57Flaps two.
31:59Flaps two.
32:01Investigators try to match the unusual oscillations by testing different flap and slat configurations.
32:11Test number two.
32:13Flaps five, slats remain retracted.
32:18NTSB investigators, they'll do anything.
32:21They love that stuff.
32:23But I would have been pretty scared.
32:29Okay, test number nine.
32:32Flaps two, slats two, three, six, and seven.
32:36Flaps two.
32:38Ready?
32:46You feel that?
32:48The flight test gives investigators a tantalizing new lead.
32:54Investigators are very careful with flight tests.
32:58To take the same aircraft, to record parameters carefully, all those things have to factor into a flight test in order to be of any use to the investigation.
33:15Here's the data from the tests.
33:18Scenario number nine should match up.
33:21To confirm their results, investigators compare the data with the FDR's g-trace.
33:29It's a perfect match.
33:32The flight test showed that extending the flaps and slats would create in the airplane oscillations found on 841.
33:41So this was the test when the plane was shaking the most.
33:45This is the one.
33:48Flaps two, slats two, three, six, and seven deploy.
33:56And are retracted 13 seconds later.
33:59They now have evidence that TWA 841's crew enacted the unauthorized procedure of pulling a slat circuit breaker and then deploying the flaps independently.
34:11But if that's what the crew did, why did the slats deploy and nearly bring down the plane?
34:22What the heck?
34:26Those slats are going to shake because you're going faster than the limiting airspeed, so I would expect it to get very noisy and probably to buff it quite a bit.
34:39The test flight indicates the slat circuit breaker was reset, which caused the slats to deploy.
34:46So we know the pilots popped the breaker to enact the procedure, but why did they push it back in?
34:56And why did it take the crew 13 seconds to realize the problem and then retract the slats?
35:04Investigators search for answers in all of the crew's statements.
35:13The lead flight attendant remembered that the flight engineer was out of the cockpit before the vibrations began.
35:18What's he doing?
35:22I'm going to take a bathroom break and get rid of these trays.
35:33I noticed the cockpit door open and I saw the flight engineer coming out with the meal trays.
35:38I didn't want him to think I was tricking my responsibilities. I immediately met him.
35:44Oh.
35:46Let me get this for you.
35:50I was kind of surprised that I'd never had a cockpit member actually bring those trays back to the cabin. They waited for us.
36:01Well, that's it.
36:03The flight engineer was out of the cockpit.
36:06And out of the loop.
36:08Investigators now have a theory about what happened in the cockpit on the night of April the 4th.
36:16The flight engineer leaves the cockpit to return the trays.
36:23With Banks out of the cockpit, Gibson launches the unauthorized procedure. The pilots deploy the flaps.
36:33What do you say we get to Minneapolis a little quicker?
36:36Okay.
36:38How are we going to do that?
36:40Watch this.
36:45Okay.
37:04Flaps two.
37:07Fancy trick. Heard about it, but I've never tried it.
37:11Works like a charm.
37:13I could see the junior crew member saying, he's the boss. Let's do it.
37:18If he says it's okay, it's okay. Today that would be unthinkable.
37:26Flight engineer returns and notices a breaker's popped.
37:30What would any good flight engineer do?
37:33He pushes it back in.
37:35Flight engineer Banks returns and notices the slat circuit breaker is pulled.
37:40He returns the breaker to the normal position,
37:43unaware that the captain had pulled it deliberately to prevent the slats from extending along with the flaps.
37:50Exactly. Normal operations resume.
37:55With flaps set for two, the slats extend automatically.
38:00The cockpit begins to vibrate.
38:01What the heck?
38:03What did you just do?
38:05What do you mean?
38:07Just now. What did you just do?
38:11The breaker was on. I pushed it back where it should be.
38:14Jesus.
38:16Flaps up. Flaps up, Scott.
38:19Flaps up.
38:24We're going over!
38:26We're going over!
38:28I bungled the maneuver.
38:31Investigators have figured out how TWA 841's crew might have lost control of a Boeing 727.
38:39But they're still missing a key piece of the puzzle.
38:43How come slat number seven never retracted along with the rest of the slats?
38:56Metallurgical report is in.
39:00Investigators turn to results from a metallurgical analysis of the T-bolt from the number seven slat on TWA flight 841.
39:17We found some shearing.
39:19Pre-existing metal fatigue.
39:24The team discovers a fracture in the T-bolt, which would have caused the slat to sag on the inside when extended.
39:33The slat is kept in the forward part of the wing, which gets all of the air forces as the airplane progresses.
39:41At 0.8 times the speed of sound, that's going to be enormous, enormous air pressure.
39:47So all that air pressure twists the sagging slat.
39:53Slat number seven can no longer retract.
39:59Under the extreme air loads of a diving plane, it finally rips off.
40:04Investigators finally understand how TWA 841 went into a horrifying dive above Saginaw, Michigan on the night of April the 4th, 1979.
40:15I'm going to take a bathroom break. I'll grab these trays.
40:17Unaware the captain was conducting an unsanctioned procedure, disengaging the slat circuit breaker to deploy only the flaps,
40:25the flight engineer resets the popped breaker.
40:31The TWA 841 is now in the air.
40:34The TWA 841 is now in the air.
40:37The TWA 841 is now in the air.
40:40The TWA 841 is now in the air.
40:42The flight engineer resets the popped breaker.
40:58What did you just do?
41:00What do you mean?
41:03Precious seconds pass as the captain tries to figure out what's happened.
41:07Meanwhile, the aircraft flies at a high speed with its flaps and slats extended perilously.
41:14The captain, passengers and flight attendants talked about feeling the vibrations in the airplane caused by extension of the slats and flaps at 39,000 feet.
41:24Flaps up. Flaps up, Scott. Flaps up.
41:28I have control.
41:29I have control.
41:31The flaps and slats retract, except for the damaged number seven slat on the right wing.
41:38The number seven slat, if it's extended, you're going to have more drag on the right side than on the left wing and that's going to cause that wing to descend.
41:47In other words, it's going to put the airplane in a right turn, which is exactly what happened.
41:51Come on, level up.
41:53But it's too late.
41:55Little does the crew know, slat number seven is still extended, keeping the plane in a roll.
42:02We're going over.
42:04TWA 841's flight crew is unable to regain control of the aircraft.
42:11Then, in a stroke of incredible good luck, slat number seven rips off the plane just 8,000 feet above the ground.
42:23The departure of the slat allowed the return of controllability to the aircraft.
42:29With the wing symmetry partially restored and the landing gear deployed, it's just enough to slow the plane and allow the crew to regain control and ultimately land the battered 727 at Detroit.
42:47Reverse thrust.
42:53The NTSB recommends additional warnings to flight crews about the dangers of high-speed deployment of flaps and slats.
43:04No punitive action is taken against the crew.
43:09NTSB conclusions are not a criminal thing.
43:13They're not a blame thing.
43:14They're not a blame thing.
43:16They're trying to prevent the next accident by offering up a probable cause that needs to be corrected.
43:29The pilots maintained their innocence, claiming they did not deliberately extend the flaps mid-flight.
43:36Captain Gibson took it to his grave with him in 2015.
43:40The other two guys aren't talking.
43:45Following this accident, newer planes now come equipped with flight computers that prevent the deployment of flaps and slats above certain altitudes.
43:57There was speculation over manipulation of controls, all that sort of thing.
44:03I've given it a great deal of thought over the past 41 years and have come to the conclusion that I'll never know what happened.
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