- 2 days ago
Air Crash Investigation Series S24E07 Pitch Battle
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TVTranscript
00:01Pilots of Colgan Air Flight 9446 fight for their lives as their plane dives towards the ground.
00:07You pull for all your work. Just keep pulling for all your work.
00:11Picture trying to do your day job while deadlifting 250 pounds.
00:16Oh no!
00:21Both pilots are killed.
00:25The wreckage reveals very little.
00:30That is a rat's nest.
00:32The cockpit voice recording provides a key insight.
00:36Listen to how exhausted they are trying to keep the nose up.
00:39But analysis of flight data turns the case on its head.
00:43This doesn't look right.
00:44Well, that was a huge aha moment for me.
00:47How is that possible?
00:48Everybody missed what was just such a simple mistake.
00:56Mayday, mayday!
01:00A Colgan Air crew prepares for the last flight of the day in a recently serviced aircraft.
01:14Weather looks good. Should be an easy ride.
01:31Captain Scott Knabe has been with Colgan Air for more than two years.
01:37Six months ago, he was promoted to captain.
01:42Scott Knabe was among the most careful and meticulous pilots.
01:48He was a very successful and very good accountant.
01:54But he had the aviation bug.
01:57How's the paperwork?
01:59Weight and balance is checked and filed.
02:01First officer Stephen Dean has been with the airline for less than a year.
02:06Did you put in for that upgrade?
02:10Actually, no, I didn't.
02:11I put in my notice.
02:13I can't afford to do this anymore.
02:15Understood.
02:17Being a young pilot moving his way up the ladder in the regionals,
02:22the first officer quickly discovered that his pay could not support his wife and daughter.
02:28So, a week before this flight, he gave notice.
02:34Don't mind these reposition flights.
02:39No passengers.
02:41No problems.
02:45Colgan Air has a small fleet of Beach 1900s.
02:49The aircraft operate as part of U.S. Air's regional arm.
02:53The Beechcraft is a smaller plane, popular for commuter flights.
03:01They fly short distances.
03:03They fly into places that the big name carriers wouldn't be able to fill up or make a lot of money.
03:13Maintenance log checked and aircraft is released.
03:18After four days of routine maintenance in Hyannis,
03:22the plane is being returned to service.
03:25Colgan 9446 will fly empty to upstate New York.
03:30Sometimes we have to resort to these non-revenue flights
03:34to reposition the plane from one location to another.
03:38Occasionally, that could also happen
03:40when you have to bring the plane to a specified maintenance facility.
03:44Today's flight from Hyannis, Massachusetts, west, to Albany, New York,
03:49should take 50 minutes.
03:52Circuit breakers, check.
03:54Checked.
03:55The pilots perform their final checks.
03:58All right, I'm not getting any radios here.
04:04Have you got anything in your headset?
04:05Check, check, check.
04:08What a cluster.
04:11When an airplane is returned back to service,
04:14pilots will expect that all subsistence are working.
04:17So you will show up to the airplane and expect that everything has been serviced accordingly
04:21and it's safe to return back to flying.
04:26After a short delay, because of a minor radio problem,
04:29flight 9446 taxis for takeoff.
04:34Takeoff terms are set.
04:36Cabin PA not required.
04:39Tower Colgan 9446.
04:41We're good to go.
04:41Colgan 9446, runway 24, cleared for takeoff.
04:51Clear for takeoff, 24, Colgan 9446.
04:54Set the power.
05:03Power set.
05:05The Beech 1900 being such a stable aircraft,
05:09as soon as it accelerates on the takeoff roll,
05:11it will reach flyable speeds in a distance as short as 4,000 feet.
05:1680 knots.
05:17And it will basically fly itself off the runway
05:20with very minimal piloting boots.
05:24V1, rotate.
05:28At 3.38 p.m., flight 9446 lifts off the runway.
05:34But it's barely gaining altitude.
05:37We have a hot elevator trim.
05:40The captain suspects there's an issue with the trim system,
05:43which is preventing the plane from climbing normally.
05:47Trim tabs on the elevator adjust the plane's pitch during takeoff.
05:54They're powered by a switch on the control column.
06:01But the captain's trim switch isn't working.
06:05If you have a trim issue on takeoff,
06:08it is very difficult to overcome.
06:11You have seconds, not minutes,
06:14because you don't have any altitude.
06:18Just 50 feet off the ground,
06:20the plane's nose is dropping.
06:24Roll back, roll back, roll it back.
06:26I got it.
06:29Knabe instructs the first officer to adjust the trim manually.
06:33A manual trim is a wheel located on the left side of the throttle quadrant
06:40that allows you to trim it into a nose-up additive.
06:43But that doesn't help.
06:47Pull back.
06:50An airplane that is nose-heavy will continuously require back pressure on the control yoke.
06:56It's heavy, buddy.
07:00Using brute force, the pilots manage to raise the plane's nose and climb away from the runway,
07:07despite the plane's determination to pitch down.
07:10Do the electric trim disconnect.
07:16The captain wants to cut the power to the trim altogether.
07:19But before the co-pilot can even find the right circuit breaker...
07:26Back, Steve.
07:29No, stay under controls with me.
07:31...the nose drops again.
07:33Put up our gear.
07:43Selecting the gear up in an airplane will reduce the amount of drag being exposed to the airstream,
07:49improving your climb performance.
07:51This would have made the pilots gain altitude at a faster rate.
07:55Forty-five seconds into the flight, the pilots still can't get the plane to climb normally.
08:0594-46 is requesting emergency back, sir.
08:09Got a runaway trip.
08:11The captain wants to return to Hyannis Airport.
08:14Colgan, 9446, roger.
08:17Right and left downwind, your choice.
08:19Report midfield.
08:21Okay, roger, will do.
08:22Using all of their physical strength, the pilots manage to level off at 1,200 feet
08:30and start the turn back to Hyannis.
08:36All right.
08:39We have a beached 1900 aircraft that just took off, reporting control problems.
08:44We need fire and rescue to runway 33.
08:49With brief respite from the struggle,
08:52Could I pull the breaker?
08:54Yeah.
08:55Pull the breaker, Steve. Pull the breaker. I have the yoke.
08:57The pilots return to troubleshooting the trim issue.
09:00Where is it?
09:01Find it.
09:03In the confusion, the first officer can't locate the breaker for the automatic trim.
09:08Look left of the silver thing, Steve. Left of the silver thing.
09:11Left of the silver thing?
09:11Left of the silver thing.
09:13Oh, the stick.
09:15Steve, stay with me.
09:16The second attempt to disconnect the trim system also fails.
09:24Less than two minutes after taking off, Colgan 9446 is losing altitude.
09:33You pull for all your worth. Just keep pulling for all your worth.
09:36Really, what he was saying is, pull for your life.
09:40Because that was the only hope they had at that time.
09:46Five miles from the airport, the pilots struggle to return to Hyannis.
09:5094-46 is requesting 33, sir.
09:5794-46, Roger. Runway 33 cleared the land.
10:02We're going to need both of us on this, Steve.
10:05Marine, Marine, pull up.
10:07The pilots use all their strength to keep their plane airborne.
10:12Steve, keep on pulling.
10:14But it's still not enough.
10:15Hold on, Steve.
10:16We have a Beech 1900 aircraft down, east of Point Gammon.
10:38Two pilots, no passengers.
10:40Two minutes after takeoff, Colgan 9446 crashes,
10:47three and a half miles from the airport in Hyannis, Massachusetts.
10:54The Coast Guard was there almost immediately,
10:57but they were not able to save the pilot and the co-pilot.
11:02Hitting the water at a very high rate of speed is like hitting cement.
11:07The pilot's bodies are recovered from the wreckage within four hours.
11:20A team from the National Transportation Safety Board, the NTSB,
11:25arrives in Cape Cod to begin the investigation.
11:29Can be posted on the recovery process.
11:31This is the second Beech 1900 to crash in six months.
11:38There was the Air Midwest accident down in Charlotte.
11:41The big question was, you know, is there anything related?
11:44Was there a fleet-wide problem?
11:51NTSB investigators consider why Colgan Air Flight 9446 crashed so soon after takeoff,
11:58killing both pilots.
11:59It's similar to an Air Midwest crash in Charlotte, North Carolina,
12:04which took the lives of 21 people.
12:07Witnesses reported that the aircraft climbed for a few seconds,
12:13and then the nose pitched up high in the air.
12:17It edged over and then literally tumbled towards the ground into a building.
12:23With hundreds of American-built Beech 1900s in service,
12:32investigators need to find out if there's a design fault with the aircraft
12:36that could put even more lives at risk.
12:42Steve.
12:43Hey, great.
12:44You can set up over there.
12:46Thanks, boss.
12:46The NTSB calls in Steve Carbone, an investigator who has been working for months on the Beech
12:531900 accident in Charlotte.
12:55What do we know so far about the cause of that other Beech 1900 crash, the one in Charlotte?
13:03We think the plane was loaded wrong, and the pilots lost control of it.
13:08A witness reported that Colgan Air 1900 seemed to struggle to hold altitude
13:12before descending into the water south of the airport.
13:14Pilots understand that altitude is their best friend, and taking off from the airport and
13:21then pretty much flying right into the ocean is a sure sign that something was wrong.
13:29Could be control problems after takeoff in both accidents.
13:35The similarities between Colgan and Air Midwest wasn't just the fact that both were Beech 1900.
13:41In both instances, the attitude of the aircraft was uncontrollable.
13:49Charlotte, they lost control of the pitch.
13:53Was it outside its center of gravity?
13:57The balancing point of an airplane is called its center of gravity.
14:02Passengers and luggage must be carefully distributed from front to back
14:06to keep the plane stable in flight.
14:11In Charlotte, investigators believe the Beech 1900 may have been tail-heavy,
14:17which caused it to pitch up after takeoff.
14:22The Colgan flight was empty, so without any passengers,
14:26maybe the center of gravity was too far forward.
14:27You could have an empty airplane and still be out of your center of gravity.
14:34They calculate flight 9446's center of gravity based on the distribution of the weight on board.
14:47And then the fuel weight was 3,271 pounds.
14:54That should do it.
15:01Look how far forward that is.
15:05Yeah, but it's within limits.
15:08The team is now certain that whatever brought down Colgan 9446,
15:13it was not related to its center of gravity.
15:19With Colgan, center of gravity didn't turn out to be an issue,
15:23even though it did have to be eliminated as a possibility.
15:26Thank you for meeting with me.
15:38Investigators turned to the air traffic controller
15:40for insight into why the pilots of Colgan 9446 lost control after takeoff.
15:47Tell me about the flight.
15:50It was a normal takeoff, about a minute after they wanted to return to the airport.
15:5694446 is requesting emergency back, sir.
16:03We have a runaway trim.
16:06He told you a runaway trim?
16:08Yeah.
16:10Pilot reported a runaway trim to air traffic control,
16:13which is a control issue.
16:14And so that information was very helpful.
16:16It helped us work smarter, not harder.
16:20Runaway trim occurs when the motorized trim tabs on the elevator malfunction,
16:25causing the plane to pitch nose-up or nose-down.
16:30A runaway trim close to the ground will be specifically challenging
16:34because pilots will have very limited time to perform the required actions
16:39to safely control that aircraft.
16:41If the pilot feels that he's having a trim runaway, there's something in the pitch system that is clearly a problem.
16:43If the pilot feels that he's having a trim runaway, there's something in the pitch system that is clearly a problem.
16:59If the pilot feels that he's having a trim runaway, there's something in the pitch system that is clearly a problem.
17:11This is very helpful. Thank you.
17:13And we're certainly going to investigate that.
17:15Will the wreckage confirm what the pilots reported
17:19and help explain what brought down a widely used commuter aircraft in just over two minutes?
17:25The flight data recorder and cockpit voice recorder of Colgan Air Flight 9446 are recovered from the sea floor.
17:44They are in good shape.
17:49Ship them to the lab.
17:51Maybe we'll get some answers from these.
17:52We were lucky in some areas where we had the flight data recorder and we had the cockpit force recorder.
18:01If we didn't have flight recorders on this one, boy, I don't know.
18:06That is a rat's nest.
18:09Investigators turn their attention to what remains of the control systems.
18:14So there's a lot of cables that go to the tail.
18:18Cables that control the elevator, the trim.
18:22And the rudder as well.
18:25I see some of the trim cable in there.
18:28Let's find as many pieces of it as we can.
18:31The trim cables are smaller and a head fractured.
18:34And so it's a big puzzle to be able to track the cables from one end to the other.
18:41Could take a while.
18:46While one team looks for the cables connecting the trim system,
18:50another focuses on the maintenance history of Colgan 9446.
18:54Could a faulty repair be connected to the pilot's report of runaway trim?
19:16Check out which inspection they were in.
19:21At Colgan Air, monthly routine inspections are divided into phases,
19:26focusing on different areas of the plane.
19:28They were working on the tail.
19:33Exactly.
19:34Which means they might have done work on the trim system.
19:37They flew in with no problems.
19:40And then on the first flight out, they couldn't control it.
19:44Something happened that was detrimental to safety of the aircraft.
19:48They spent at least four separate days on the inspection.
19:53What took them so long?
19:58It doesn't say.
20:01A phase check, in this case what they call a detail check,
20:05you can do it within an eight-hour period,
20:07especially on a 1900 because it's a very simple aircraft.
20:11But the fact that it took four days led us to understand
20:15that there was something else that occurred.
20:18Mind if I record this?
20:20Yeah, sure.
20:26I was wondering,
20:27why did it take you so long to do your phase checks?
20:31We definitely found a lot of stuff that we needed to replace.
20:41I got the flashlight.
20:46Just bring the light a little to my left.
20:48Yeah, the trim actuator's worn out.
20:56Cables from the cockpit connect to the trim actuators.
21:01Mechanical rods in the tail that move the trim tabs up or down.
21:05What did you do when you found the problem with the actuators?
21:10We removed the old ones, ordered new ones, and installed them.
21:15And the new ones went in easily and it worked fine?
21:18Uh, well, not exactly.
21:27Okay, Bob, run the trim system, please.
21:33Did the actuators move?
21:36No.
21:37Neither did the trim cable.
21:38The test revealed problems with the actuator replacement.
21:42When we replaced the actuator, we bent and kinked the cable that connects it to the cockpit controls.
21:50It was just a dumb mistake.
21:54If he's an experienced, competent mechanic, why would he do that?
21:59And the answer was, he was not.
22:02He was a new hire, had never done this job before, and their training program allowed him to do this without any supervision.
22:10I ordered a new cable and installed it.
22:14That's why it took four days.
22:17And you tested it?
22:19Yeah, yeah.
22:22After the new cable was installed, maintenance workers performed a visual check.
22:28Okay, let's give it a try.
22:30When examining the paperwork after the accident, everything looked in order.
22:35That's it, it's working.
22:37Thanks, man.
22:38Yet, we still had an issue because it didn't explain what actually happened.
22:45With no credible leads to explain why the pilots thought they had a trim issue,
22:50investigators must rely on what they learned from the CVR, the cockpit voice recorder.
22:56Okay, let's hear it.
23:08The recording runs about 17 minutes from the moment the pilots powered up on the ground.
23:17Could the pilot's communications reveal why Colgan Air Flight 9446 failed to maintain altitude?
23:30Hi, it's maintenance.
23:31This is Colgan 9446.
23:33Hey, I was told to stay in contact with you for the whole trip.
23:36Yeah, they might call you and turn you back because they did find a problem.
23:41I don't know for sure.
23:44Why would maintenance want to turn them around?
23:47Maybe there was something wrong with the plane.
23:50Somebody had doubts about the work they did.
23:52I, as a mechanic, could not ever release an aircraft that there was a question of its airworthiness.
24:03You cannot say, well, you know, the wings are pretty, pretty strong on there.
24:08We're 90% positive they're not going to fall off.
24:11You can't do that.
24:12I'd prefer not to fly something if it's broken.
24:16I'd rather you do it.
24:18Because you are the pilot in command.
24:20All right.
24:22Now, broken airplane?
24:23I wouldn't want to screw it up.
24:27Okay, it'll be a standard Colgan takeoff.
24:30If things get spooky on the runway, we'll abort it.
24:35Did you just say spooky?
24:38As investigators continue to review the CVR,
24:42the flight crew should not be that nervous.
24:45They're surprised by the pilot's concern about the condition of their aircraft.
24:51Sadly, the aircraft manuals went down with the aircraft.
24:56So exactly what the maintenance personnel put in those logbooks for the pilots to review,
25:03we will never know.
25:07When did they first realize there was a serious issue with their aircraft?
25:12Looks like merely seconds after takeoff.
25:15They identified a trim issue seconds after takeoff, long before contacting the controller.
25:31The captain tries to disconnect the trim system on his yoke,
25:43but his attempts fail.
25:45They're commanding nose-up trim inputs, but it doesn't seem to help.
25:5794-46 is requesting emergency back, sir.
26:06Got a runaway trim.
26:08Okay, there it is.
26:10Runaway trim.
26:11Just like the controller said.
26:13Did they try pulling the breaker?
26:19Looks like it.
26:23Pull the breaker, Steve.
26:24Pull the breaker.
26:25I have the yoke.
26:27Listen to how exhausted they are trying to keep the nose up.
26:31Where is it?
26:32Find it.
26:33The pilot was calling for the co-pilot to pull the circuit breaker
26:37so they can stop these electrical signals that are commanding the runaway trim.
26:43But you have to have time to pull the circuit breakers.
26:47Look left of the silver thing, Steve.
26:48Left of the silver thing.
26:49Left of the silver thing?
26:50Left of the silver thing.
26:52Oh, the stick.
26:53Steve, stay with me.
26:55The co-pilot had to abandon pulling the breaker in order to help the captain.
27:01Steve, keep pulling!
27:05Oh, no!
27:14Two minutes.
27:16I'm going to take off the impact.
27:20Those guys fought the trim right until they hit the water.
27:25We need to find out what's going on with that trim system.
27:30Was there a mechanical issue with the trim that the pilots could not overcome?
27:39Okay, let's have a look.
27:42We were lucky.
27:43We had a solid-state flight data recorder.
27:45Some of the old, old flight recorders might only have 16 parameters.
27:49This one had a lot more.
27:50Investigators examined the FDR, the flight data recorder,
27:56to determine why the pilots reported a runaway trim.
28:01This doesn't look right.
28:03What do you mean?
28:04This trim data is way out of calibration.
28:07It either wasn't maintained properly, or it was damaged in the accident.
28:14And so on this one, we didn't have exact trim position.
28:20If the FDR wasn't calibrated, those readings are worthless.
28:22It's a major setback.
28:27Without the FDR data, the investigators may not be able to confirm the pilot's report of a runaway trim.
28:35But we have all those other parameters, pitch, elevator.
28:39Let's ask the lab to try and calculate what the trim position would be.
28:43Performance case study.
28:44It's a great idea.
28:48A case study like this would help us to define whether the elevator trim tape cables had anything to do with the accident.
28:56It was one other thing that we could check into to verify the results we were finding.
29:02Will the team be able to get accurate trim data?
29:05Steve, keep on pulling!
29:07And explain why two experienced pilots were unable to keep their plane in the air?
29:12Oh, no!
29:13Oh, no!
29:34So, the lab took the control column positions and extrapolated for trim.
29:40I see. Excellent.
29:43A performance study using the FDR data gives the NTSB a new look at the trim inputs on Flight 9446.
29:54So, they adjust the trim to takeoff right here.
29:58Yeah, it's part of the before taxi checklist.
30:04Before taxi checklist.
30:07Before taxi weather radar.
30:09On standby.
30:10On standby.
30:11Yeah, trim set.
30:120.5.
30:14Takeoff trim set.
30:16The takeoff trim was set to 0.5 nose down instead of 0.5 nose up.
30:24That's odd.
30:26When's the next input?
30:28Right after takeoff.
30:30That's right after he said, we've got a hot elevator trim.
30:37The plane is pitching down instead of up.
30:41How's that possible?
30:42How's that possible?
30:43Investigators discover the plane wasn't responding to the pilot's nose up trim inputs.
30:50And it happens again here, one last time, a few seconds later.
30:56Roll back, roll back, roll it back.
30:57I got it.
30:58The more the first officer tries to manually trim the nose up, the more the nose drops.
31:07It's like the trim is reversed.
31:10A good analogy is learning to drive.
31:14Imagine how weird it would be if you turned your steering wheel right and the car went left.
31:19Talk about confusing.
31:22And exhausting.
31:25You pull for all your worth.
31:27Just keep pulling for all your worth.
31:28They were dealing with the backwards trim, which I don't know how anyone would have ever fathomed that.
31:35Investigators calculate that within a minute of takeoff, the pilots would have required 250 pounds of force to hold the nose up.
31:47Steve, keep pulling.
31:50Hold on, Steve.
31:54How on earth could they have wired a trim system backwards?
32:05The team retrieved this from the wreckage.
32:10Oh, great.
32:13In an effort to prove the trim cables on flight 9446 were reversed,
32:19investigators study a key piece of the trim system found in the wreckage.
32:25Okay.
32:26The trim cable is threaded and wrapped around this drum,
32:30and then runs in a loop from the cockpit to the tail.
32:40Maybe they fed the cable incorrectly around the drum.
32:45Let's check the installation manual.
32:47Looks like maintenance threaded the drum correctly.
33:05Yeah.
33:07But how did they install it?
33:08The cable drum is one piece of the story that was telling us that it might have been incorrectly rigged.
33:16But we needed to dig deeper.
33:19Okay.
33:20Let's give this a try.
33:23The NTSB considers how the maintenance crew installed the drum.
33:28Looks good.
33:33Here we go.
33:34Yep.
33:35That's it.
33:44Well, that doesn't fit.
33:47No.
33:56Yeah, the only way to install this thing...
33:58like this.
34:03Investigators discover that in order for the drum to fit the pin,
34:08it had to be flipped, thereby crossing the wires.
34:12Well, that was a huge aha moment for me.
34:15The manual, the way it was depicted at that time,
34:18it could mislead somebody.
34:21In this case, it did.
34:22We have a hot elevator trim.
34:27Because the wires were crossed, the trim tab operated in reverse.
34:33Kill the trim, kill the trim.
34:38Pull back.
34:40Pull back.
34:43They knew they had a malfunction.
34:45They just couldn't figure out what it was.
34:49There's only one explanation.
34:52The maintenance manual must be wrong.
34:55I'll check with the manufacturer.
34:56But even if the manual is wrong, why didn't anyone notice the trim cables were crossed?
35:03I'll check to see if the maintenance team got an inspector to sign off on the work.
35:08They are a second set of eyes.
35:11They have to be the one who is making sure that the job is done right.
35:15That is what an inspector does.
35:16After you installed the drum, did an inspector sign off on the work?
35:22Yes, he did.
35:24In fact, he assisted with it.
35:27He assisted?
35:29Yep.
35:31The inspector cannot get in there with wrenches.
35:34He cannot get in there and tell you, okay, you got to put this bolt here or anything like that.
35:39Thanks for your help tonight.
35:40The thing is, with an inspector being part of the job, he's making the same mistakes that the people that he's supposed to be overlooking are making.
35:50So he becomes part of the problem.
35:53The inspector, who helped with the installation, didn't notice the crossed wires and signed off on the work.
36:01The last time we spoke, you said you tested it?
36:05That's right.
36:06That's right.
36:09After the new cable was installed.
36:12Okay, let's give it a try.
36:14Maintenance workers performed a visual check.
36:17Yeah, that's it. It's working.
36:19Yeah, thanks, man.
36:25Yeah, that's coming in now.
36:29Thanks.
36:34Hey.
36:36Hey.
36:37What'd you find out?
36:39The inspector helped with the installation, so not exactly an objective inspection.
36:44What about you?
36:46Well, it's just like we thought.
36:48The drawing in the manual's wrong.
36:51This is how the drum should have been oriented when they threaded the cable.
36:57The manual shows the slots on the drum are facing out.
37:01But the correct way to thread the cable is with the flat side facing out.
37:07Here's what I don't get.
37:09They tested the trim system when the installation was complete and said it was working fine.
37:14How's that possible?
37:15How's that possible?
37:17Well, I know.
37:18Hey.
37:19Hey.
37:20Hey.
37:21Hey.
37:22long night found a recording of the trim check test you're kidding it's on the CVR recorded
37:43well before their flight in order for the mechanics to do an operational check correctly they had to
37:50power the airplane up okay Bob run the trim system please so the power was on the CVR was on it
37:57worked to our advantage I think I know how the trim tabs passed the visual ground test even
38:02though they were running in reverse are you good in the cockpit yeah okay let's give it a try trim
38:16nose up trimming nose up that moving up looks good now trim nose down trimming down okay yeah that's it
38:32that's working thanks man sounds like a normal test no they got it backwards we hear the cockpit
38:44called trim up and the maintenance worker says he sees the trim tab move up that is reversed if you
38:52trim nose up the trailing edge moves down in the opposite direction the same is true for trimming
38:59the nose down it is counterintuitive but you're right it is an easy mistake to make checking a
39:10trim system can be a little confusing you have to make sure you're on the same page with the other
39:14person are you talking tab up or nose up because tab up is nose down the ground guys missed it okay
39:22why didn't the pilots catch it trim test is definitely a pre-take-off checklist item but then they run it
39:32according to the transcript they ran the checklist
39:40before start checks uh parking brake it's set pre-flight complete before taxi checklists before taxi weather radar
39:54they skipped the trim check
39:58i'm biased because i have a pilot background i feel like that first flight of the day checklist
40:05is crucial that's where you can catch it even if they had checked it would they have known whether
40:13the trim system was reversed just by looking at the direction the trim wheel was spinning good point
40:19pilots test the trim by pressing the trim switch and monitoring the direction in which the manual trim
40:27wheel spins to trim nose up the wheel would turn backwards investigators recreate the reverse trim system on
40:39the same model of beach 1900 that crashed to determine whether the pilots could have detected that the
40:45trim was reversed let's give this a try investigators trim the plane nose up
40:57the wheel is moving backwards the way the pilots expected it to turn even though the trim cable was
41:05reversed the wheel still moves backwards as it should what is in error is the fact that the drum is
41:14upside down it is now running the cables in the wrong direction so everything in the cockpit is correct
41:21the test reveals the pilots of colgan air flight 9446 v1 rotate wouldn't have realized the cables were
41:31reversed even if they had checked them prior to takeoff we have a hot elevator trim
41:36in their final report the ntsb concludes the cause of the accident was the improper installation of the trim
41:48cable system and beechcraft's erroneous depiction of the elevator trim drum in their maintenance manual
41:55ah the stick see stay with me these factors ended up sealing the pilots fate
42:04the pilots grueling efforts kept the plane in the air for more than two minutes but in the end the extreme
42:28stick pressures were too much for the pilots to overcome picture trying to do your day job while deadlifting 250 pounds
42:37it's just too much hold on steve oh no
42:47this accident was a hundred percent preventable first and foremost is your plane has to be flyable and
43:07it's only flyable if the manuals and maintenance and pilot instructions make sense the colgan air
43:149446 report echoed similar findings to the other beach 1900 crash months earlier in charlotte north
43:22carolina improperly installed control cables were also a factor in the air midwest accident that killed 21
43:30people if you looked up the term maintenance accident dictionary those two accidents would be there colgan and air
43:38midwest were poster childs for maintenance accidents if colgan properly followed the maintenance program as
43:48dictated by the regulations this accident never would have happened after the accident beechcraft's maintenance manuals
43:57were amended and airlines adopted stricter procedures for airplane checks after undergoing routine maintenance
44:05the person in the cockpit missed it the people on the elevators missed it the inspector missed it
44:11everybody missed what was just such a simple mistake
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