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00:00Coop.
00:02Pilots de Airborne Express
00:04Are testing a plane
00:06that's been recently modified
00:08Kick the tires, light the fires
00:10and make sure she's exactly as advertised
00:12Next thing is our stall series
00:14These pilots were trying
00:16to test the stall warning system
00:18Feeling some buffet here
00:20That's a stall right there
00:22But something goes terribly wrong
00:24That's number 2 engine
00:26That's a number two engine.
00:30Pull up.
00:32Really? Really?
00:35Flight 827 crashes into a mountain in Virginia.
00:40Everyone on board is killed.
00:41It was just complete devastation.
00:45While the flight data confirms the plane entered a stall.
00:48And then here, airspeed falls off a cliff.
00:51It doesn't explain why the pilots weren't able to recover from the very condition they were testing.
00:58It's a sobering thought and a significant one.
01:00D-Day, D-Day.
01:02It's three days before Christmas at Piedmont Triad International Airport in Greensboro, North Carolina.
01:29The crew of Airborne Express Flight 827 and three technicians in the cabin have been waiting more than four hours for maintenance to be completed.
01:40Think we're getting out of here tonight?
01:41At this rate, I think we're all going to be spending Christmas together in this cockpit.
01:45What do you think, Terry?
01:47I think you can explain that one to my wife and kids.
01:49Flight 827, aircraft cleared and released. Have a good flight and a Merry Christmas.
01:55Roger 827, Happy Holidays, Dispatch.
01:58Finally.
01:59Just after 5 p.m., Flight 827 is given clearance to fly.
02:08The flight engineer is 52-year-old military veteran Terry Welty.
02:14Taxi and pre-takeoff checklist. Brakes.
02:19Flying tonight is 37-year-old Captain Keith Lemming.
02:24Checked.
02:25Checked.
02:26Cabin and film compressors are off.
02:28Anti-skid.
02:30Anti-skid.
02:32Armed.
02:32While not flying, 48-year-old Captain Garth Avery is the designated pilot in command.
02:38They were very experienced as pilots.
02:41The flight engineer was incredibly experienced and they all knew the DC-8 had many, many hours
02:46in this interplane.
02:48Taxi and pre-takeoff checklist complete.
02:51Tower, ABX 827 Heavy is ready to go.
02:54The flight crew is operating a modified McDonnell Douglas DC-8.
03:01The DC-8 is an incredibly reliable machine and it always has been.
03:06The DC-8 is a long-range, narrow-body jetliner introduced in 1959.
03:16As long as you use it exactly the way it was designed, they're just as tough as nails.
03:21At 5.40pm, flight 827 takes off.
03:33Positive rate.
03:42Gear up.
03:43Positive rate.
03:441,000 feet.
03:50Roger.
03:51Although it's a lesser-known airline, Airborne Express, or ABX, is one of the largest cargo
03:58carriers in the United States, after both Federal Express and UPS.
04:03In a bid to expand its fleet, ABX purchased the aircraft that would become Flight 827 and modified
04:11it before putting it into service.
04:16ABX 827 is 2,500 for 5,000.
04:22MCT set.
04:24Ignition off.
04:26But before this plane can be added to the fleet, it has to be taken for a test flight.
04:34This is known as a functional evaluation flight, or FEF.
04:40A functional evaluation flight is basically to see that everything is as it's supposed to be.
04:45Kick the tires, light the fires, go out and fly, and make sure she's exactly as advertised.
04:52After departing Greensboro, Flight 827 is scheduled to spend about two hours flying the FEF before
04:59returning to the airport.
05:01ABX 827, for our maintenance check, can we get a block of 1,0 to 1,2000?
05:07The flight crew needs a dedicated block of airspace to perform the tests.
05:11Could you take a block of 1,13 to 1,15?
05:15We can do that.
05:19ABX 827, roger.
05:21Climb and maintain block altitude of 1,3000 through 1,5000.
05:24Having reached a quiet block of airspace, the crew works its way through the FEF checklist.
05:35Scoops.
05:38On.
05:40The DC-8 scoops are part of its pressurization system.
05:43Didn't get the left one, try again.
05:48It's really common on test flights to have issues crop up.
05:52This airplane had undergone so many changes that it needed a thorough test flight.
05:57All right.
05:58Scoops.
05:59Off.
06:04Left one ain't working.
06:05With multiple redundancies built into the pressurization system, the pilots are safe to continue their flight.
06:17ABX 827, turn right, heading up 360.
06:21Vectors for traffic.
06:22Air traffic control monitors the airspace, redirecting flight 827 when necessary.
06:29ABX 827, right 360.
06:30And then we're going to do our manual drop.
06:36You ready for hydraulics to come off, Keith?
06:39Yeah, go right ahead.
06:40Okay, go ahead, Terry.
06:42The manual drop tests the plane's landing gear without the use of hydraulics.
06:48Okay.
06:49Gear freefall 1.5, VS0.
06:52Okay, you ready?
06:53I'm ready.
06:54Gear down.
06:57Gear down.
06:593 green.
07:01Got it.
07:04We're getting a little bit of ice here.
07:08The biggest hazard from icing is that it changes the shape of the wing.
07:13And the airplane doesn't fly nearly as well as it did.
07:17The crew comes up with a plan to avoid performance issues from ice buildup.
07:22Garth, if we go up 15, I think we can get out of this stuff.
07:26Uh, yeah, you can go up there.
07:29We've got that block.
07:30As the flight climbs out of the weather, the crew continues the tests.
07:46Next thing is our stall series.
07:48For the stall series, the pilots will intentionally slow the airplane until it's just about to stall to determine when the stick shaker activates.
07:59Most commercial planes use a stick shaker system.
08:02It's a vibrating warning on the control column that alerts the pilots to take action before the plane actually stalls.
08:11We should stall at 122.
08:13I've got to set that in my interior bug.
08:16The pilots set their target speed for when the plane is expected to stall.
08:20Mindset.
08:21Shaker 128.
08:22You just call all your numbers, I'll record them.
08:26They have to write down the airspeed at which the stick shaker triggers.
08:31And then they have to write down the airspeed at which the stall begins.
08:35Captain Lemming slows the plane at a rate of one knot per second to reach the stall speed.
08:44Feeling some buffet here.
08:46The pilots detect a change in the aircraft.
08:49Yeah, that's pretty early.
08:52As an airplane approaches stall, it starts talking to the pilots.
08:56The airplane starts vibrating or buffeting.
09:00They quickly take action to avoid a stall.
09:03Set max power.
09:05133.
09:12Then, one of the plane's left engines begins to surge.
09:22That's number two engine.
09:27But that's not normal, and you know it's not normal, and so something like that's going
09:31to get your attention.
09:33Pull it back.
09:39You got it.
09:41The plane now banks to the left.
09:46And begins to drop.
09:47The pilots attempt to level the wings and slow the plane's descent.
09:59All right.
10:01Okay?
10:02Got it.
10:03Got it.
10:03Realizing that the plane is descending below his jurisdiction, the controller assigns the pilots
10:20to a new radio frequency.
10:22827 changed to Indianapolis 128.4.
10:26But the controller's calls to change frequencies go unanswered.
10:35The flight crew is busy trying to recover the plane.
10:45ABX827, Indianapolis 128.4.
10:49ABX827, going to stay on this frequency a minute, descending through 8,000.
10:53Call you right back.
10:54ABX827, you're in an emergency descent?
10:59Yes, sir.
11:03Airborne express flight 827 is out of control and plummeting to the ground.
11:08Rudder.
11:09Yeah, got it.
11:09Seeing that flight 827 is in trouble, the controller checks air traffic in the area to find a safe altitude
11:24for the plane.
11:28Okay.
11:28Um, can you hold 7,000?
11:32But there's no answer.
11:36Flight 827 is less than 5,000 feet from the ground and descending fast.
11:41Now bring it back.
11:44Left rudder.
11:48Okay, good.
11:49Easy.
11:50They could tell they were in an emergency.
11:52They could tell they'd lost control.
11:53They were probably frightened to death.
11:55The pilots continue their efforts to recover the aircraft, but are now too low.
12:00Pull up.
12:03Terrain, terrain.
12:04Pull up.
12:06Really?
12:06Pull up.
12:06Really?
12:09Airspeed, low.
12:11Pull up.
12:11Just half an hour into a standard test flight.
12:18The DC-8 crashes into the East River Mountain in Narrows, Virginia.
12:26ABX-827, do you copy?
12:31ABX-827, do you copy?
12:35No one has survived.
12:37The mountains lit up, and there was an explosion, black, smoke, and red and blue flames coming up off it.
12:49News of the crash quickly spreads throughout the community.
12:55Grief counselors arrived today at Airborne's headquarters to help family and friends cope with their loss.
13:02Obviously, it's just a terrible time for everyone here, particularly at...
13:07...at this time of year.
13:08Bob McIntosh from the NTSB, the National Transportation Safety Board, leads the investigation.
13:15We know this was a maintenance examination flight.
13:19Obviously, it was not successful, and that's about all I can tell you right now.
13:24The wreckage site certainly presented some challenges.
13:27We were going to have to deal with some mountainous terrain.
13:31We had to get to work.
13:32Benjamin Berman is one of the first team members to arrive at the crash site.
13:40I got to the top of the mountain, and I looked out at the scene.
13:44And it was just complete devastation.
13:49I really thought, you know, what is it that could have brought that plane down?
13:54That's our job as NTSB investigators.
13:56Investigators begin their painstaking efforts to transport pieces of the demolished plane to a hangar for examination.
14:07We found the four corners.
14:10Looks like the plane was intact when it hit the mountain.
14:12So, if you can see all four corners, which are the nose, the right wing tip, the tail, and the left wing tip,
14:20in close proximity probably means the airplane was intact until it hit the ground.
14:28This particular wreckage scene told us that we most probably had a loss of control
14:33and that we were going to have to find the reason for that loss of control.
14:38We recovered the CVR and FDR.
14:42Let's get them off to Washington.
14:44The cockpit voice recorder was going to tell us not only what they said, but how they said it.
14:51While investigators wait for the CVR download,
14:59Got the checklist for the FEF.
15:02they review the checklist the flight crew was using during the functional evaluation flight
15:06to get a better understanding of what they were doing prior to the crash.
15:13Looks like standard FEF stuff.
15:15They're testing the flaps, rudder, landing gear, stall system.
15:23There's nothing unusual on the list of tests the pilots were performing.
15:28Maybe there was a problem with the plane before the FEF.
15:31I'll get Berman to talk to the maintenance team that modified the plane.
15:37It was an old airplane, but it had just come out of a major retrofit.
15:42Can you take me through exactly what you guys did to the airplane?
15:46Well, it was a fairly major overhaul.
15:48Investigators learned that extensive maintenance and modifications
15:52were carried out on the aircraft over the course of six months.
15:56Yeah, it looks like you guys pretty well took the whole thing apart and put it back together, huh?
16:01As we looked at the maintenance records,
16:03we could find that there was a great deal of work that had been done on the aircraft.
16:08Perhaps something had fallen through the cracks.
16:12Could technicians have overlooked something during the modification of the airplane,
16:17causing the pilots of Flight 827 to lose control?
16:21Pull up.
16:23Corrine, corrine.
16:24Really?
16:25Pull up.
16:25Really?
16:28I've got the dispatch logs for the plane right here.
16:32Investigators review Airborne Express Flight 827's dispatch logs
16:36to see if any malfunctions were reported after the plane was released from maintenance.
16:41Looks like they finished the modifications and delivered the plane on December 15th,
16:46one week before the crash.
16:50Wait a second.
16:53This wasn't the pilot's first attempt at this flight.
16:56The fact that they tried to do the flight earlier, that was really relevant.
17:05Look here.
17:06The pilots conducted a partial FEF the day before the crash.
17:11Scrapped it midway through, low hydraulic pressure.
17:14That can mean getting the landing gear down and in place or not,
17:19or being able to power the flight controls or not.
17:22If the hydraulic pressure is not right, that's very serious.
17:26Okay.
17:26And what do you think caused the low hydraulic pressure?
17:31Did a hydraulic issue cause a loss of control?
17:35Got it.
17:36Okay.
17:36Maintenance crews say that they suspected that trapped air in the lines
17:39led to low hydraulic quantity indication.
17:41Did they fix it?
17:42Yeah.
17:43They replaced nose gear actuator the day of the accident.
17:45But was that the end of it?
17:47Or could our pilots end up having issues with the hydraulics again?
17:54We needed to figure out what had been going on.
17:58Could something have gone wrong in that maintenance?
18:04Investigators are able to recover the plane's rudder components from the crash site.
18:09They examine them for any signs of damage to the hydraulic system.
18:14No pre-impact hydraulic leaks.
18:17Hydraulic system was working fine.
18:20The hydraulic system wasn't a probable cause for the mishap and loss of control.
18:26If it wasn't the hydraulic system, what was it?
18:30We should call the witness, listen, maybe somebody saw something.
18:41You were outside your home at the time?
18:44And what did you hear?
18:45The team begins to interview witnesses to see if anyone heard or saw something that could
18:50point to the cause of the crash.
18:51The local newspaper people were there asking people what they had heard and seen that night.
18:57Witnesses described seeing the plane descend out of the clouds at a steep angle and hit the mountain at high speed.
19:15Thank you so much for your time.
19:20I think we've got something.
19:23Three witnesses confirmed they could hear the plane making a banging sound, followed by a slapping sound.
19:32Kind of odd noise.
19:34It sounded kindly low and it started coming up real loud.
19:38If air flow entering the engine is disrupted, it can cause the engines to backfire.
19:55If air flow over a wing is disrupted, it can make a slapping sound.
20:03Both can be signs of a stall.
20:05If the witness reports were true, it suggested that possibly there was an engine issue that may have been part of the sequence of events.
20:16However, it would require a further examination of the flight data recorder.
20:20NTSB investigators turned to the plane's flight data recorder to confirm whether flight 827 was in a stall before it crashed.
20:31Isolate the airspeed.
20:35There's a gradual reduction in airspeed here.
20:39One knot per second. Looks like they were setting up for the stall series.
20:42And then here, airspeed falls off a cliff.
20:47That's a stall.
20:48Let's see the engine parameters.
20:52They search for further confirmation that flight 827 stalled.
20:56That looks like a compressor surge from the number two engine.
21:04That tracks with what the witnesses said they were hearing.
21:07Lack of airspeed and a compressor surge are clear signs that the plane stalled.
21:12Give me the roll angle.
21:13A roll reversal is a phenomenon that occurs when a plane banks steeply to the left and right.
21:30The airplane started to roll radically from side to side.
21:36If you look at the flight recorder traces, you can see an 80 degree bank one way, 115 degree bank the other way, which is more than, more than knife edge flight.
21:45And now the airplane does exactly the opposite of what you were asking it to do.
21:56Yeah, that's four roll reversals before the crash.
21:59How did the crew of flight 827 allow their plane to get so out of control?
22:09With the arrival of flight 827's cockpit voice recorder, or CVR, investigators zero in on the test the pilots were conducting immediately before the plane stalled.
22:20Okay, are you ready?
22:23Ready.
22:26Next thing is our stall series.
22:28We should stall at 122.
22:30I'm going to set that in my interior bug.
22:34Mindset.
22:36Shaker 128.
22:37If you just call all your numbers, I'll record them.
22:44Investigators listen to the pilots working their way through the stall series.
22:50Feeling some buffet here.
22:52Yeah, it's pretty early.
22:59So the plane entered the stall sooner than they expected.
23:02Yeah.
23:04When I was looking through the transcript before, there was something that Captain Lemming said earlier in the flight.
23:13Captain Lemming, we're getting a little bit of ice here.
23:15Garth, if we go up 15, I think we can get out of this stuff.
23:21Uh, yeah, you can go up there.
23:22We've got that block.
23:25So ice builds up, disrupts airflow over the wing, decreases lift, increases drag.
23:30And the plane would have stalled at a higher airspeed than the calculated.
23:33Did ice accumulation on flight 827 cause a premature stall?
23:41It's happened before.
23:47December the 12th, 1985.
23:50Evidence suggested that shortly after taking off from Gander International Airport in wintry conditions,
23:57a build-up of ice on Arrow Air Flight 1285 caused the plane to stall at a higher airspeed,
24:04leading to a crash that killed all 256 people on board.
24:09Investigators study meteorological reports to determine if flight 827 was flying through icing conditions.
24:19There's a scattered area of light rain here along 827's flight path.
24:25Cloud tops out at around 14,000 feet.
24:29What was our altitude block again?
24:31Uh, 13,000 to 15,000.
24:33The type of weather they were in the night of the accident was really conducive to icing.
24:40They were in prime territory to pick up ice whenever they were in the clouds.
24:44What speed did the pilots say they expected the stall?
24:48Stall 122, shaker 128.
24:51Well, according to the FDR, the plane stalled at 126 knots.
25:02It's only four knots earlier.
25:05So even if there was ice, it was likely to have had little impact.
25:09I mean, certainly not enough to make the plane unrecoverable.
25:11Whether there was a great deal of contribution from ice, we could never determine.
25:19But the consensus was that it was not a major element in the cause of the accident.
25:29You said stall 122 knots, shaker 128?
25:33Well, when we were listening to the CVR, I don't remember hearing the stick shaker.
25:36The purpose of the stick shaker is to get your undivided attention, not only by noise, but by shaking you.
25:50Because there's only one thing that that's telling you, and that is, if you slow anymore, I'm going to stall.
25:55Let's have a listen.
25:57Did the pilots receive proper warning that their plane was entering a stall?
26:04Feeling some buffet.
26:05Yeah, it's pretty early.
26:08That's a stall right there.
26:09That ain't no shaker.
26:15So they're slowing the plane down, waiting for the shaker to activate.
26:19Then all of a sudden, they're in a stall.
26:21No warning.
26:21So the shaker failed.
26:24With no stall warning there, the pilots had, in a sense, a right to believe they weren't stalled.
26:30Well, what's going on here?
26:31Well, it's not a stall because the stick shaker's not vibrating.
26:34Well, the question is, when did it fail?
26:37During the flight or before?
26:39To determine if the stick shaker malfunctioned, investigators searched the wreckage for stall components that might have survived the fiery crash.
26:58Nothing, huh?
27:05Yeah, that's what we thought.
27:06The stall system was completely destroyed.
27:09We never were able to exactly identify what that failure point was in the system.
27:18Our team wanted to find out how much maintenance and inspection had taken place on the system.
27:25With no clues in the wreckage, NTSB investigators speak to the maintenance technician about Flight 827's stall warning system.
27:38All right, thanks for your time.
27:39Did you test the stick shaker?
27:43Yeah, we did.
27:45On...
27:46On December 5th.
27:50Two weeks before the accident.
27:52How extensive a test.
27:53Quite extensive.
27:56Come look.
27:56The shaker, the shaker, the heating components.
28:01The stick shaker system passed all those pre-flight maintenance checks.
28:07What about the transducer?
28:10Let me check.
28:12The transducer is a small flap nestled in the recessed part of the wing.
28:18It moves backwards when airflow is detected.
28:21When there is insufficient air over the wings, it moves forward and triggers the stick shaker to activate.
28:32No.
28:35No, it doesn't look like we tested the transducer.
28:40That part is not covered by the pre-flight test.
28:45It suggests that the failure of the stick shaker to work was a bad transducer.
28:51But to me, why it failed wasn't as important as what the effect of it failing was on the crew.
29:02Doing some buffet here.
29:04Yeah, it's pretty early.
29:05That's a stall right there.
29:06That ain't no shaker.
29:08Even without the stick shaker activating, the flight crew knew they were in a stall.
29:15That's number two engine.
29:17Bring it back.
29:18Okay, good.
29:19But if they knew...
29:22Left rudder.
29:22Why couldn't they recover?
29:24Easy.
29:24Horrain.
29:24Bring it back.
29:25Pull up.
29:26Rudder.
29:27Really?
29:28Horrain.
29:28Horrain.
29:28Horrain.
29:37Investigators returned to Flight 827's CVR to get a better sense of the actions the pilots took when their aircraft went into a stall.
29:45That's a stall right there.
29:47That ain't no shaker.
29:49Set max power.
29:51One thirty-three.
29:55So as soon as they recognize they're in a stall, they push power to the engines.
29:58That's the right move.
30:02That's number two engine.
30:03There's the engine, Serge.
30:05Pull it back.
30:06So what'd they do next?
30:15All right.
30:16Okay.
30:18Start bringing the nose back up.
30:20They pulled the nose up.
30:28But that would make the stall worse.
30:30Pulling back on the control column in response to a stall is inconsistent with a normal stall recovery and would not reduce angle of attack and break the stall.
30:41Well, that's what would have triggered the roll reversal.
30:47How'd they deal with that?
30:50Rudder?
30:51Got it.
30:52Rudder.
30:53Got it.
30:55Left rudder.
30:56Left rudder's buried.
30:58Investigators discover that in addition to moving the control wheel right and left, the pilots also use the rudder to stop the plane from rolling.
31:06You have to be ahead of it, and that's a very difficult thing to do.
31:13So they spend almost a minute trying to fight the roll reversal with the rudder.
31:19No mention of a stall.
31:23Investigators suspect that the pilots were so preoccupied dealing with the roll reversal that they failed to realize that the plane was in a stall.
31:31Still doesn't explain why Captain Lemming would have pulled back on the yoke to try to recover from the stall.
31:44To recover from the stall, you can't pull back.
31:47You need to point the nose of the airplane down even more in order to gain speed, or you will not recover.
31:54You will fly into the mountaintop in Virginia.
31:57Parane.
31:58Parane.
31:58Pull up.
32:01Parane.
32:01Parane.
32:05And we wanted to know why.
32:07Why did he do that?
32:09Especially at those most critical moments.
32:17Morning, Bob.
32:18Looking to see if there's anything in ABX's operations manual on the DC-8.
32:23Here's a copy.
32:23Investigators search through ABX's procedures to understand why Captain Lemming pulled back on the control column to recover from Flight 827's stall.
32:35Wait.
32:37Bob, did you see this?
32:38It says that priority in a stall recovery is to maintain altitude by increasing the pitch.
32:48Pulling back on the control column increases the pitch of an aircraft.
32:52Well, it might be okay for an approach to a stall, but not for an actual stall.
32:58So the things that you do to recover from an approach to stall are totally different from what you do to recover from an actual stall.
33:09If you're right over the trees, you've got to try the approach to stall recovery because you're going to hit the trees.
33:15If you're at 36,000 feet and you stall, if you don't put the nose down 5 or 10 degrees, you're not going to recover.
33:23That can't be the current procedure, can it?
33:37I've got a joint memo with the FAA.
33:40Investigators discover an update to Airborne Express's flight test procedures.
33:44What's it say?
33:46The updated procedure called for a reduction of pitch to recover from a stall.
33:50The revised procedure called for pilots to lower the nose when entering a stall, the opposite of what Captain Lemming did.
34:00The change was made after a loss of control incident in May 1991.
34:06May 1991?
34:07What flight was that?
34:10It was a DC-8 doing a post-modification FEF.
34:14The same plane and flight as A-27.
34:16On May the 16th, 1991, another Airborne Express DC-8 lost control during an FEF.
34:26The pilots managed to recover from the stall and the policy has been to reduce pitch during a stall ever since.
34:32So why didn't the crew of flight A-27 use the updated procedure?
34:41Okay.
34:41We learned that the director of flight technical programs was responsible for the procedures, the checklists, and the selection and training of pilots.
34:52As a result, we wanted to talk to him to learn more.
34:55The NTSB meets with the airline's director of flight technical programs to determine why the crew of flight A-27 didn't follow the updated procedure.
35:04Just have a few questions to ask, and then I'll let you get back to work.
35:08Of course.
35:10How do ABX pilots train to recover from a stall?
35:13I tell them, whatever you do, don't lose altitude.
35:15So, if you're in a stall, you set max power, and you increase the pitch of the aircraft.
35:20Well, that's different from the updated policy, which calls for a nose-down pitch recovery.
35:26Correct.
35:27He just didn't agree that that was necessary.
35:30If you increase the pitch, it will make the stall even worse.
35:33If the engines are properly spooled as you're approaching a stall, you can power your way out of it.
35:39The director believed that if the engines were running properly, pilots could increase thrust and fly out of a stall.
35:47He had his own opinions about what should be done, and they were not in agreement with the proper procedure.
35:57See, what I don't get is, old procedure, new procedure, there is no procedure that says to pull back for the duration of the stall.
36:12I keep going back to the way they were dealing with this role reversal.
36:18Rudder.
36:19Rudder.
36:20Got it.
36:21And left rudder.
36:22The crew were unable to recover the airplane in the approximately 90 seconds that it took from when the lack of the stick shaker was identified to when it impacted terrain, and our question was why.
36:38Investigators assess ABX's DC-8 flight simulator to see exactly how the flight crew experienced a stall during their training.
36:46Now I'm going to slow this thing down into a stall.
36:55There's the shaker.
37:00There's the stall.
37:02Now we're going to pull back on the yoke like our pilots did.
37:05So I continued to raise the nose up higher and higher, and I was just astounded at what the simulator did.
37:15Or mainly what it didn't do.
37:26Well, we're in a stall, and there's no roll, no pitch down, nothing like you would see in a real-life stall.
37:34If this is how they were trained, they would have no idea how a stall truly feels.
37:48Their training was not only zero training, it was negative training.
37:53It gave them a false impression of what they would experience.
37:56They would have been startled at what the wings did with the roll.
38:03Okay, easy.
38:04Don't, don't.
38:05And they would not have recognized it necessarily as a symptom of a stall, because in their simulator, it didn't have that symptom.
38:14Maybe they didn't realize they were still in the stall, but surely there were other indicators that they were falling out of the sky.
38:21Why didn't the pilots of Flight 827 realize they were diving towards a mountain?
38:32Okay, put yourself in the pilot's shoes.
38:38You realize you're in a stall.
38:41Feeling some buffet here.
38:43Yeah, it's pretty early.
38:44That's a stall right there.
38:45That ain't no shaker.
38:47You push power to the engines, pull back on the yoke.
38:50Start bringing the nose back up.
38:52Your number two engine surges.
39:06That's number two engine.
39:08Pull it back.
39:11Now you're dealing with a roll.
39:19Planes banking left and right.
39:22You're applying rudder.
39:23Rudder.
39:24Got it.
39:25Rudder.
39:26Rudder.
39:27Got it.
39:28You've got ATC in your ear telling you to switch frequencies.
39:31827, change.
39:3210, Indianapolis, 128.4.
39:35You look outside, what do you see?
39:39Nothing.
39:44Right.
39:45Because it's pitch blackout and you're in the clouds.
39:48There's no visible horizon, you're just flying on instruments.
39:51They had no visual cues.
39:53Exactly.
39:55You're now removing the visual aspect of a horizon out there that can help anchor you.
40:02You're just stacking the deck against yourself.
40:04Now, the question is, what were they doing flying a stall series test at night in the first place?
40:13Investigators review the flight's dispatch logs to retrace the pilot's steps on the day of the accident.
40:18The FEF was scheduled for 1.20 p.m., but the maintenance delays pushed it past sundown.
40:25Had they just pushed it to the next day, none of this would have happened.
40:28So why didn't they?
40:30Why go through with the FEF at night?
40:32One of the key decisions was to conduct the check flight later at night than they'd planned in the darkness hours.
40:45And so, you know, did anyone pressure them to doing that?
40:49What is the ABX policy on when to fly an FEF?
40:53Investigators returned to ABX's Director of Flight Technical Programs to find out why the pilots proceeded with an FEF at night.
41:01No policy necessarily, just a preference to fly them during the day.
41:07Do ABX pilots understand the risks of flying an FEF at night?
41:10Sure.
41:11And I'd rather they conduct them during the day, but there's no prohibition against doing them at night.
41:17What are the recommended weather conditions for flying an FEF?
41:20Preferences to fly in clear skies and not on instrument, but we have no specific restrictions on that.
41:27We discovered that there was no written policy prohibiting this flight from being conducted at night.
41:36The NTSB's investigation has uncovered numerous factors that led to the crash of Flight 827.
41:44Stick shaker malfunction, incorrect stall procedure, negative simulator training, FEF at night.
41:52If just one of these factors not been present, the crew would likely have survived.
42:01I think this accident was caused by a failure to recognize that a functional evaluation flight requires rigorous preparation
42:09and criteria and controls to be placed on it to protect the pilots who are flying it.
42:17Start bringing the nose back up.
42:19This was not God reaching down and slapping an airplane out of the sky.
42:25There were reasons for this happening, and this could have been avoided.
42:30In the wake of the crash of Flight 827, the NTSB makes a series of recommendations
42:36to make functional evaluation flights safer and to better prepare pilots for stall conditions.
42:42This accident brought a lot of significant changes to the industry.
42:48We issued recommendations to try to improve airline oversight and FA oversight of functional evaluation programs,
42:58and those efforts were successful.
43:03Flight simulators used for airline training were made much more realistic.
43:08Every airline pilot receives training in recovering the airplane from the high altitude stall,
43:15where they have to use this Airborne Express revised stall recovery procedure to get the job done.
43:22The report also recommends a revision to the DC-8 maintenance manual,
43:27calling for regular calibration and testing of the complete stall warning system.
43:33There might have been other airplanes out there, you know, flying around in service,
43:37where the stall warning system really wasn't working.
43:40The strength of aviation safety is a direct result of learning the most we can learn from every single accident.
43:54This wasn't an accident in vain.
43:56Yes, it could have been prevented, but now we know how.