Air Disasters (2022) Season 17 Episode 5: Pacific Plunge
Air Disasters (2022) Season 17 Episode 5: Pacific Plunge
Heroic flying isn't enough to overcome neglectful maintenance in the tragic accident of Alaska Airlines Flight 261.
#documentary #historical
Heroic flying isn't enough to overcome neglectful maintenance in the tragic accident of Alaska Airlines Flight 261.
#documentary #historical
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TVTranscript
00:00The pilots of Alaska Airlines Flight 261 wrestle with an MD-83 nose-diving toward the Pacific
00:15Ocean.
00:16We got it under control here.
00:19No, we don't.
00:22The airplane pitched down and rolled.
00:25Mayday!
00:27Mayday!
00:29It actually gets inverted, upside down.
00:32Amazingly, the pilots managed to keep the aircraft flying.
00:36This is like an air show maneuver.
00:40Speed brakes.
00:42Just seconds from impact, the pilots right their aircraft.
00:46They had one shot to save the plane or all would be lost.
00:50Here we go!
00:58Oh, fuck!
01:17Alaska Airlines Flight 261 takes flight, climbing into sunny skies over Puerto Vallarta, Mexico.
01:25Gear up.
01:30Gear's up.
01:32Captain Ted Thompson is an Air Force veteran.
01:35He's flown with Alaska Airlines for 17 years.
01:41Thank you, sir.
01:43First Officer Bill Tansky has been flying for almost four decades.
01:47He's the one flying today.
01:50The pilots on 261 were highly regarded by their fellow pilots.
01:57These were really top-notch aviators.
02:00Flaps up.
02:04Flaps.
02:08The MD-83 is flying north to San Francisco for a stopover.
02:13From there, it's a short hop to its final destination, Seattle, Washington.
02:20Free flight attendants tend to the 83 passengers on board.
02:29Fifteen minutes after takeoff...
02:33That's strange.
02:35...the pilots become aware of a problem.
02:40The plane's out of trim.
02:43Trim refers to small adjustments to the horizontal stabilizer
02:47that maintains the pitch of the aircraft.
02:52When that light goes on, it tells the crew,
02:55you're going to have a problem adjusting the nose up or down,
02:58which is, of course, crucial for flight.
03:03The warning light indicates the horizontal stabilizer is jammed,
03:07pushing the nose down slightly.
03:10Let's check this out.
03:12Autopilot off.
03:14Good idea.
03:18Whoa!
03:20What's it doing?
03:22It's pushing down.
03:24First Officer Tansky uses all his physical strength
03:28to keep the plane's nose up.
03:30The first officer is hand-flying the airplane,
03:33so he's manually got his hands on the control yoke
03:37and increasingly there's more and more pressure
03:40that he's having to hold.
03:42He's using a lot of arm muscle,
03:45so this is something that they want to fix.
03:50Well, we're still climbing. That's good.
03:53Let's get to 3-1-0 and figure this out.
03:58By pulling back on the control column,
04:01the pilots can deflect the plane's elevators enough
04:04to enable the aircraft to continue climbing.
04:1021 minutes after takeoff,
04:12Flight 261 levels off at 31,000 feet.
04:21Manual says try the pickle switch.
04:28Pickle switches are literally just a button
04:32on the control column,
04:34and it moves the horizontal stabilizer
04:37such that it will push the nose up or down.
04:43Controls in the cockpit activate a two-foot jack screw in the tail.
04:47As the jack screw turns, it moves the stabilizer up or down.
04:53They were having to go through the manuals,
04:56and they were asking each other,
04:58What do you know? What can we do? What can we try?
05:04Nothing. Why don't you try?
05:10Captain Thompson tries to activate the horizontal stabilizer
05:14using what pilots call the suitcase handles.
05:19Not nice.
05:21It's like trying to start your car.
05:24They were trying everything they could think of
05:27to get their plane to respond.
05:30Let's try it on autopilot.
05:34They hope the autopilot can keep the plane level.
05:41The plane is steady.
05:45I'm thinking we get this plane on the ground sooner rather than later.
05:48Yeah. Maybe LAX?
05:51Call dispatch.
05:53If you have a control problem,
05:56you have to get that plane on the ground.
06:01Dispatch 261, requesting a diversion to LAX.
06:05Our longitudinal trim system is inoperative.
06:09Captain Thompson contacts Alaska Airlines flight dispatcher in Seattle.
06:14Dispatch 261, copy that.
06:17If you want to land in LA, for safety reasons,
06:20we'll be looking at over an hour delay because of a flow problem right now.
06:26I didn't really want to hear about the flow.
06:28I'm concerned about suitable airports.
06:31Do you have a wind at LAX?
06:34It's 260 at 9.
06:38The pilots compare the wind conditions at Los Angeles and San Francisco airports.
06:45The pilots on this flight took such care
06:48considering all their options on runways.
06:53There's a headwind at LAX,
06:55but at San Francisco, there's a crosswind.
06:58260 at 9 versus a direct crosswind.
07:02For safety reasons, I think something that lowers the ground speed makes sense.
07:08The headwind at LAX will help make it a safer landing.
07:13Once you're lined up for the LAX runway,
07:16you've got perfect winds coming right at your nose.
07:20It blows off the Pacific Ocean.
07:22It's predictable. It's constant.
07:24And it slows down your plane.
07:31You're the guys with the horizontal situation.
07:35Ten minutes after rerouting,
07:37a mechanic at Alaska Airlines' maintenance facility in Los Angeles
07:41contacts the crew.
07:45Affirmative.
07:47The maintenance facility can talk directly to the pilots
07:50to provide them the expertise on the problem that they're dealing with.
07:56Did you try the suitcase and pickle switches?
07:58Yeah, we tried just about everything.
08:00If you've got any hidden circuit breakers, we'd love to know about them.
08:04Yeah, I'll look into the circuit breaker guide as a double check.
08:08And the alternates inoperative, too.
08:10Yep, our horizontal stabilizer appears to be jammed. The whole thing.
08:15Okay, thank you, sir.
08:17See you when you get to LAX.
08:21The response from Alaska Airlines' maintenance was basically no response at all.
08:26They provided them no help.
08:28Really, the most they ever said to them,
08:30did you try the pickle switches and the suitcase handles,
08:34which is one of the first things that they did.
08:38All right, let's try the pickle switches again.
08:43You got it?
08:44You got it?
08:47The captain is warning the first officer as a reminder,
08:51when we click the autopilot off, be ready.
08:54Because it's going to require a lot of effort from you right then.
08:59This will click the autopilot off.
09:11Stabilizer motion.
09:15Stabilizer motion.
09:17The nose of the plane drops far more than the pilots anticipated.
09:24Holy crap.
09:28The airplane is pitched down significantly,
09:31and the airframe is shaking violently.
09:34They know something is very desperately wrong with the airplane.
09:38The problem is suddenly much worse.
09:41Flight 261 begins to nosedive.
09:46What are you doing?
09:48It got worse.
09:51They have to get the nose back up,
09:53or they'll have an unarrested descent all the way to the ocean.
09:59Help me back.
10:01Help me back.
10:03Okay.
10:05The crew of Alaska Airlines Flight 261
10:08struggles to regain control of their MD-83.
10:13They pull back on the control yoke, holding a lot of force.
10:18The plane is shaking violently.
10:21The plane is shaking violently.
10:24The plane is shaking violently.
10:26They have to regain control of their force.
10:30Center, Alaska 261.
10:32We are in a dive here.
10:35I've lost control of the vertical pitch.
10:38Alaska 261, say again, sir?
10:40We are in a vertical dive at 26,000.
10:45They are now three minutes from impact.
10:49Speed brakes.
10:51The pilots deploy the speed brakes,
10:53which are vertical surfaces on the wings of the plane that increase drag.
10:58And he wanted to slow the plane down,
11:00and it would also give them more of a chance physically
11:03to pull the plane out of the dive.
11:13The speed brakes arrest the dive.
11:18Using all their strength,
11:19the pilots bring the aircraft back under control at 24,000 feet.
11:28Once we get the speed slowed, maybe we'll be okay.
11:32In 80 seconds, the plane has dropped 8,000 feet.
11:38The pilots pulled out of the dive with pure brute force.
11:44We got it back under control here.
11:49No, we don't.
11:51Even though they've managed to pull out of the dive,
11:53it requires extreme effort to keep the nose of the plane level.
11:57Okay, it really wants to pitch down.
12:00They're really having to work physically at holding the nose up on this jet.
12:06They're in a fight for control of the airplane.
12:10It's a lot worse than it was.
12:11Yeah, we are in much worse shape now.
12:15This is a very experienced crew.
12:16These aviators have had problems in flights before, but nothing like this.
12:25Maintenance 261, are you on?
12:2922 miles from Los Angeles,
12:31Captain Thompson updates Alaska Airlines maintenance,
12:35hoping for advice on how to land safely.
12:38Yeah, 261, this is maintenance.
12:40Yeah, we've tried both the pickle switch and the suitcase handles,
12:43and it ran away full nose trim down.
12:45Oh, it ran away full trim.
12:48Yeah, now we're worse than we were.
12:51He's explaining that when he commanded nose up trim,
12:56the trim system moved nose down,
12:58moved in opposite direction of the way he commanded it,
13:01and it did so very quickly, and it did so with a lot of force.
13:06And you're getting full nose trim down and no nose trim up, correct?
13:10That's affirmative.
13:11We went full nose down, and now I'm afraid to try it again
13:14to see if we can get it to go back in the other direction.
13:18He is reluctant to try to move it again for the concern
13:23that if it gets worse yet,
13:25that they could lose control of the airplane entirely.
13:29If you want to try it, that's okay with me.
13:31If not, that's fine.
13:33See you at the gate.
13:34After the maintenance base at LAX said,
13:37oh, we'll see you at the gate,
13:39the pilots knew they were on their own.
13:42All they had left was they had themselves,
13:45their physical strength, and their wits.
13:49To land the plane, the pilots need to figure out
13:52how to control their descent
13:54without using the plane's trim system.
13:56You want to try the trim switch again or not?
13:59Uh, I don't know.
14:01You want to try the trim switch again or not?
14:04Uh, no, I don't know.
14:08It's up to you, man.
14:10They're literally test pilots,
14:12and they're having to utilize decades of experience
14:16to try to work their way through to a solution.
14:20We better talk to the people back there.
14:22Yeah, I know.
14:26Captain Thompson tries to reassure the passengers.
14:31We've had a flight control problem.
14:33We're intending to go to Los Angeles.
14:37We're working on it,
14:38and I don't anticipate any problems
14:40once we get a couple systems back on the line.
14:49With Los Angeles in sight,
14:51the pilots prepare for an emergency landing.
14:55Try flaps 15, 11.
14:58Let's go to 11.
15:01The pilots test the plane in a landing configuration.
15:07Okay, we're pretty stable here.
15:10But we got to get down to 180 knots.
15:15The jet is very badly damaged,
15:17and they need to understand and find a way
15:21to control the pitch of the jet
15:24all the way through the landing.
15:26If it's controllable, we ought to just try and land it.
15:29First Officer Tanski suggests a risky high-speed landing.
15:34Okay.
15:36Let's head for L.A.
15:41Their predicament was dire.
15:44They would not be able to pull the plane up
15:47and do a go-around.
15:49The only chance they had was one shot to get it on the ground
15:53or all would be lost.
15:55But as soon as they come up with a plan...
16:00You feel that?
16:02Yeah.
16:04...the pilots hear thumps at the back of the plane.
16:07Then, disaster strikes.
16:11The airplane pitched down and rolled.
16:13They know that they are in a life-threatening situation.
16:17This is pilots' nightmare.
16:19You're running out of time.
16:21If they do not control the jet,
16:23very quickly, they'll lose the airplane.
16:27Mayday!
16:30Mayday!
16:34Push and roll!
16:36Push and roll!
16:3818,000 feet above the Pacific Ocean,
16:41Flight 261 rolls left and goes into a dive.
16:47This is like an air show maneuver.
16:49The Blue Angels do this.
16:51The Thunderbirds do this.
16:55Dropping at 160 feet per second,
16:58the plane is running out.
17:03Okay, we are inverted.
17:06Now we got to get it up.
17:09When the airplane was inverted,
17:11this is a very difficult situation
17:13because they've got to try to determine
17:16if they can maintain control of it
17:18and get the airplane back right side up.
17:24The plane starts responding.
17:26They're pushed on the control column
17:28to prevent the possibility of the stall,
17:31and then they roll the airplane toward wings level
17:34in an attempt to maintain control of it.
17:37Push, push, push! Push the blue side up!
17:40The top side of an attitude indicator is blue like the sky,
17:45and so they need to get the blue side
17:47of the attitude indicator back on the top.
17:52On the ground, LAX controllers
17:54have lost contact with Flight 261.
17:57Skywest 5154, traffic at your 1 o'clock is Alaska MD-80.
18:01Do you see him up there?
18:03They look for help from other pilots.
18:05Yes, sir. Definitely in a nose-down position.
18:08Descending quite rapidly. He's inverted.
18:11Okay, keep your eye on him.
18:13Alaska 261, are you with us yet, sir?
18:2113,000 feet over the ocean,
18:23the pilots' efforts seem to pay off.
18:26The plane's nose starts to rise, but it's still inverted.
18:30Okay, let's kick rudder.
18:32Left rudder! Left rudder!
18:35The pilots are kind of hanging upside down like bats,
18:38and it was very difficult to reach the rudder pedal.
18:42Left rudder! I can't reach it!
18:44Okay, right rudder! Right rudder!
18:47Their one hope is if they could kick that rudder,
18:51they could flip the plane back over.
18:54Okay, we've got to get it over again.
18:58At least upside down we're flying.
19:08As the pilots fight to get the plane the right way up,
19:14the engines on Flight 261 fail.
19:18There was a disruption in the airflow into the engines,
19:22and it caused a lost thrust.
19:26Speed brakes.
19:30Got it.
19:31Their demeanor was determined, collected.
19:35They were giving everything they had.
19:38The windscreen's full of the ocean.
19:40They're not going to solve this.
19:42Ah! Here we go!
19:48He's hit the water. He's down.
20:06Search-and-rescue helicopters are immediately dispatched
20:09from coast to coast.
20:12Search-and-rescue helicopters are immediately dispatched
20:15from Coast Guard stations.
20:18Search teams find debris floating 2.7 miles north
20:22of Anacapa Island off the coast of California.
20:27In addition to pieces of the plane,
20:29searchers are finding personal effects.
20:31A shoe, a passport, a postcard.
20:36Aviation safety advocate Mary Schiavo represents
20:39the families of six passengers from Flight 261.
20:45I remember this person's possessions.
20:49All the pictures were still in the wallet,
20:52in the pants pocket.
20:58Except for the picture of his wife.
21:01And so we knew by that and by how they found things
21:05that he had been clutching.
21:08That was really important to her.
21:13Rescuers search for survivors throughout the night.
21:16None are found.
21:23All 88 passengers and crew on board Flight 261 are dead.
21:32It's a terrible, tragic thing, of course.
21:35But, you know, we have a real well-established procedure here
21:41for how these tragedies are handled.
21:45Investigators from the NTSB,
21:47the National Transportation Safety Board,
21:50are assigned to find an explanation for the crash.
21:54LAX Maintenance is saying the pilots reported a jammed stabilizer.
21:58NTSB systems investigator Jeff Gazzetti joins the investigation.
22:03We knew quite a lot just from the transmissions
22:06between the flight crew and Los Angeles.
22:11Maybe they had a mechanical problem.
22:15Looks like they tried both switches. No luck.
22:18Plane pitched. Full nose trim down.
22:22We immediately began to research the horizontal stabilizer trim system
22:27to see how it was designed, how it functioned,
22:30and how the crew operated it normally.
22:35The leading edge of the horizontal stabilizer is raised or lowered by a jack screw.
22:41When activated, it moves up or down through an acme nut,
22:45changing the angle of the horizontal stabilizer.
22:52We need to see the jack screw assembly.
22:55Let's hope it's all in one piece.
22:58Investigators wonder how the horizontal trim system could have failed.
23:03I'll get this to the Navy.
23:06Recovering parts of the stabilizer system could give investigators important clues.
23:14But the wreckage field lies on the bottom of the ocean,
23:17at a depth of 700 feet, well beyond the reach of scuba divers.
23:21We were able to tell the Navy what to look for, what the high-priority targets were.
23:27U.S. Navy crews use side-scan sonar to pinpoint the location of the wreckage.
23:34Remotely operated vehicles equipped with robotic arms are used to recover pieces of Flight 261.
23:44The black boxes are retrieved two days after the crash.
23:52Nine days into the investigation, essential parts of the horizontal stabilizer are also recovered.
23:59We got the jack screw.
24:02And with the brainpower we had, we had a fighting chance to find out exactly what went wrong during this flight.
24:15What's this stuff?
24:17Investigators wonder if recovered parts from the horizontal stabilizer of Flight 261 can provide clues about why it failed.
24:26It's some kind of metal.
24:29What they see is puzzling.
24:33We saw this little thin piece of metal that we thought looked like a slinky.
24:39That really struck us as something very odd.
24:47Why isn't the nut attached to the jack screw?
24:55Normally, the lower end of the jack screw is threaded through an acme nut.
25:01When we looked at that and saw that the jack screw wasn't part of the acme nut, we asked ourselves, how can that happen?
25:08That really just blew our mind.
25:11The jack screw and the acme nut were found a few feet apart.
25:14They must have separated mid-flight.
25:19Threads an eighth of an inch thick inside the nut should hold it securely to the jack screw.
25:35Look at this.
25:37There's something unusual about the nut.
25:40Incredible.
25:41Incredible.
25:43It's completely stripped.
25:46When we finally looked inside the acme nut, it revealed that there were no threads inside of it.
25:53Let's talk to Metallurgy.
25:58It was shocking and stunning to us to see something like this.
26:01No one thought that you could get those thick threads to rip out.
26:08Interesting.
26:10Metallurgist Joe Epperson examines the stripped nut and the jack screw.
26:15It became immediately apparent that what we were looking at was actually the remainder of the threads that were inside the nut.
26:28Looks like the jack screw stripped the threads of the acme nut.
26:32The next step in the process was to figure out how the threads were reduced to such an extreme degree and then stripped out of the nut.
26:48There's some grease here on the bottom.
26:53The team studies residue observable on the jack screw.
26:57The way to prevent wear is by lubrication.
27:01With grease.
27:03And in the case of an extreme wear event, you want to look at, is there grease where it's supposed to be?
27:14And there's some here at the top.
27:18In flight, the jack screw rotates inside the nut.
27:22To prevent wear, it needs to be lubricated regularly.
27:27There should be more grease here in the middle.
27:29That's the working area where it rotates the most.
27:33When we first looked at the jack screw, there was very minimal signs that there was any grease on it at all.
27:44It was in the ocean for a week. Did the water wash the grease away?
27:49I don't think so. Grease doesn't wash off that easily.
27:55There's still some remnants here, but none in the middle.
28:00We did find a little bit of a remnant of grease at the very upper end and at the very lower end.
28:09It was very easy to conclude that being in the ocean had not washed away the grease from the working area of the jack screw.
28:20How could it be that there's so little grease on this jack screw?
28:30Grease goes through here during the lubrication process.
28:36During maintenance, grease is applied to the interior of the nut through a small valve called a zerk fitting.
28:44So, the zerk fitting is this fitting right here.
28:49And what mechanics have to do is put a grease gun hose in here and then squirt grease into this little grease fitting
28:55that goes inside this passage.
28:58That zerk fitting should have preserved and kept the remnants of whatever grease it saw last.
29:07What's that?
29:12It's packed with dried grease.
29:15I've been around grease long enough to know that if you don't replenish it,
29:19and if you just leave it, eventually it dries up and gets hard,
29:25and it basically says that it had not been replenished.
29:32How long has it been clogged like this?
29:36At least a year, maybe more.
29:40Finding this blockage suggests a long-term abuse of the grease.
29:45I'd say we have a maintenance issue here.
29:48Time to talk to the airline.
29:51We were very suspicious about how well this component was lubricated, or whether it was lubricated at all.
30:00And so we had our doubts as to whether or not this component was being properly maintained by the airline.
30:07NTSB investigators traveled to the Alaska Airlines Operation Facility in San Francisco.
30:14You worked on the plane in September 1999, is that true?
30:18Yes, I did.
30:20They tracked down the mechanic who was responsible for the last lubrication of the jack screws,
30:25and they found that there was a lot of grease on the jack screws.
30:29They found that there was a lot of grease on the jack screws.
30:31They tracked down the mechanic who was responsible for the last lubrication of the jack screw assembly,
30:37four months before the accident.
30:41Could you walk us through how you lubricate the jack screw assembly?
30:45I'll tell you this, it's not my favorite job.
30:51The team learns that jack screw lubrications are done most often on the night shift,
30:56outside the hangar, sometimes in the rain.
31:01You're working off high lift trucks, which will sometimes move with a gust of wind.
31:07The airplane moves with a gust of wind.
31:10You're up and 30 feet off the ground.
31:13Some mechanics don't like that job.
31:16They're not stable up there.
31:18To reach the jack screw assembly, you remove a panel first.
31:22How do you apply the grease?
31:25I use the papers.
31:27Sometimes I put a big glob in my hand to make sure it's on there.
31:30Aircraft, especially large aircraft, need grease.
31:34They need to have lubricants, and it's messy.
31:39The most effective way is to fill your hand with grease
31:43and actually move it up and down on the jack screw,
31:47filling all the screw grooves, filling them with grease.
31:51What about greasing the Acme nut?
31:54Investigators focus on how the mechanic greased the Acme nut on the jack screw.
31:59We use a grease gun to do the zerk fitting.
32:03You pump grease in until you see fresh grease coming out.
32:07How do you know whether the lubrication is being done properly
32:10and when to stop pumping the grease gun?
32:14I don't.
32:16Would you be able to see the grease coming out from the top of the Acme nut during lubrication?
32:20No, I can't remember looking to see if there was.
32:25One of the first things that that tells me
32:28is that he couldn't have known that that zerk fitting has taken grease.
32:32You have no idea that it's clogged.
32:34So we found a variety of ways in which mechanics lubricated this component,
32:40and that gave us some pause, because it's a very critical component,
32:44and if you don't lubricate it properly, you could end up with an accident.
32:47If you don't lubricate it properly, you could end up with an accident,
32:50like the one that just happened.
32:52The team discovers that the methods Air Alaska mechanics use
32:56to lubricate the jack screw assembly don't follow maintenance standards.
33:01The last time the jack screw was lubricated was about four months before the accident.
33:09But it's not just the way the jack screw assembly is being lubricated that bothers investigators.
33:15It's also the frequency.
33:17And before that?
33:19January 1999.
33:21They're doing it every...
33:262,500 hours?
33:29They can see there's a long period between lubrications.
33:34Is that even within regulations?
33:37I'll find out.
33:42We knew we had kind of a research project on our hands.
33:44Some of the documents that we requested from the manufacturer, from the FAA, from the airline,
33:50came in the form of internal memorandums from engineering departments,
33:55or requests from maintenance to extend an interval.
33:59It really began to paint a picture of how the lubrication intervals were extended.
34:06Check it out.
34:08The airline made multiple requests to extend the intervals on the lubrications.
34:15In 1987,
34:18the interval between lubrications was 500 hours.
34:25The intervals between lubrications are measured by the number of lubricants used.
34:29It was 500 hours.
34:32The intervals between lubrications are measured by the number of hours the plant is in the air.
34:38In 1991, it goes up to 1,200 hours.
34:45By 1996, it increases all the way up to 2,500 hours.
34:55They just continued to extend, extend, extend.
35:00Approved by the FAA?
35:02Yeah. Every one of them was approved.
35:08Investigators conclude that the lubrication of jack screws was not only conducted poorly,
35:14it was also performed less and less frequently.
35:18If you're going to extend these lubrication functions,
35:20then you better be doing something to make sure that what you're doing is correct.
35:25But even if the lubrication wasn't being done properly,
35:28regular inspections should have caught the wear on that acme nut.
35:33True. They should have inspected it regularly.
35:37Was the jack screw assembly on Flight 261 inspected when and how it should have been?
35:43We looked at the maintenance records for information about the last check.
35:47I've got something.
35:51Investigators dig deeper into the records of Flight 261
35:55to find out how the jack screw assembly was inspected.
35:59Yeah, this doesn't look right to me.
36:03The team finds paperwork which reveals that during a routine inspection,
36:08a mechanic at the airline's Oakland facility observed that the acme nut
36:12A mechanic at the airline's Oakland facility observed that the acme nut was badly worn.
36:19You're sure the reading is .040?
36:22A mechanic who did that wear check reported that he found it to be at the limit.
36:31This nut was wearing fast and something needed to be done.
36:37The lead mechanic ordered the nut to be replaced.
36:42This was evidence that someone had caught the fact that this acme nut was worn out.
36:48Most airlines, the decision would be,
36:51we will get the piece to the airplane as soon as possible and replace it.
36:56But the entry is crossed out. I don't get it.
37:01Well, when we saw that they had crossed out the first entry, it was very suspicious.
37:05Something was up. It was fishy to us.
37:08We have to find out what went on here.
37:13September 27, 1997
37:19Do you remember inspecting an MD-83 on September 27, 1997?
37:24I remember it well.
37:26Investigators contact John Liotin, the lead mechanic who reported the worn acme nut on flight 261.
37:36I wrote up the evaluation.
37:39The nut is worn down. Replace it.
37:45It was an alarming discovery.
37:48In order for that aircraft to be safe to fly, that nut assembly, at the very least, must be replaced.
37:57There's no doubt in my mind.
37:59It was the end of my shift.
38:02When I came back the next work day, the plane was closed up.
38:08The plane returned to service with the worn nut.
38:14If the nut had been replaced, the plane would still be flying.
38:19And 88 people would still be alive.
38:25How could a maintenance facility allow the airplane to be put back into revenue service with the wear that it found on the acme nut?
38:36When investigators probed further, they learned that the amount of wear on the acme nut was rechecked by other mechanics.
38:44They determined that it was just within minimum limits.
38:49Alaska Airlines maintenance misses a warning sign.
38:53The wear on the nut should at least have been monitored, but it wasn't.
38:59The next time that jack screw was looked at was in the NTSB laboratory.
39:04The plane flew with the worn nut for two more years before it took off from Puerto Vallarta on the day of the accident.
39:12Gear up.
39:15First Officer Tansky and Captain Thompson had no idea that their stabilizer was on the verge of failure.
39:25That's strange. The plane's out of trim.
39:28The plane's out of trim.
39:31The team turns to the voice recorder to find out how the devastating chain of events unfolded on board flight 261.
39:46Let's check this out.
39:48Autopilot off.
39:50Good idea.
39:54Whoa!
39:55Whoa!
39:57Thirteen minutes after takeoff from Puerto Vallarta, the worn threads in the acme nut caused the jack screw to jam, preventing movement of the horizontal stabilizer.
40:08Try it again.
40:11The captain's trying to rectify the jammed stabilizer.
40:15While cruising at 31,000 feet, the CVR picks up a sound of a click followed by a thump.
40:25We think that the pilot was moving his thumb switch on his yoke in an attempt to move the jack screw through the nut.
40:32The threads finally give way, and the jammed jack screw pulls up through the nut, causing the stabilizer to move upwards.
40:40A stopper is all that prevents it from separating completely.
40:48It got worse.
40:51With the horizontal stabilizer pushing the nose further down, the plane goes into a state of emergency.
40:57With the horizontal stabilizer pushing the nose further down, the plane goes into a dive.
41:04Through sheer brute force, the pilots hold the jack screw in place and recover the plane.
41:13Okay, it really wants to pitch down.
41:21You feel that?
41:23Stop. Let's hear that again.
41:27But eight minutes later, there's another series of thumps.
41:35You feel that?
41:38The stopper holding the jack screw in place finally gives out.
41:48Push and roll!
41:50The damage to the stabilizer makes flight 261 uncontrollable.
41:55The plane rolls over and dives toward the ocean.
42:00Push, push, push, push the blue side up!
42:03Flying upside down, the crew makes a last-ditch attempt to right their plane.
42:12Speed brakes!
42:15Got it!
42:17The pilots of flight 261 give everything they have to save the plane.
42:20It was just total professional fighting for that plane till the very end,
42:26and they expressed the realization that the fight was over.
42:34Ah, here we go!
42:36Ah, here we go!
42:48I was sickened by what I listened on the CBR.
42:54This accident could have been prevented.
43:02They greased that jack screw.
43:04This doesn't happen.
43:13The amount of money that would have saved these lives.
43:19It's a cup of coffee.
43:21It's literally a few dollars of grease.
43:27I still get angry about it.
43:30In the wake of the accident,
43:32the intervals between jack screw lubrications at Alaska Airlines
43:36is reduced from 2,500 hours to 650 hours.
43:41We lost 88 people because of lack of lubrication.
43:46This is a maintenance accident, pure and simple.
43:52It is truly a tragedy.
43:54It was just one of those cases that you work on that's never going to leave you.
44:00Not ever.
44:03It was tough.