Air Disasters (2022) Season 17 Episode 8: Pitch Black
Watch the crew of Air Illinois Flight 710 fly in the dark in a desperate move to save battery power... and their plane.
#documentary #historical
Watch the crew of Air Illinois Flight 710 fly in the dark in a desperate move to save battery power... and their plane.
#documentary #historical
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TVTranscript
00:00After losing their electric generators, the pilots of Air Illinois Flight 710 shut down
00:10one system after another to conserve their battery power.
00:15It was probably the most sickening feeling for both of them.
00:21But efforts prove futile.
00:26All the passengers and crew are killed.
00:30MTSB investigators examine the plane's electrical components for clues.
00:35There's no short circuit.
00:37What about the batteries?
00:40No signs of arcing.
00:43The cockpit voice recording raises more questions.
00:46Are you using these lights here?
00:49I'll get that one down.
00:50Well, they're doing the right thing.
00:51Turning things off to reduce the load.
00:54So what happened?
00:56You got a flashlight?
00:57Yep.
01:26Air Illinois Flight 710 departs from Capitol Airport in Springfield, Illinois.
01:36Gear up.
01:38Thirty-two-year-old Captain Lester Smith has been with Air Illinois almost five years.
01:45He's one of its most experienced pilots.
01:49Gear is up.
01:50First Officer Frank Tudor has been with the airline for three years.
01:56He's considered one of its top first officers.
02:001,000 feet.
02:05The pilots are flying a Hawker Siddeley 748.
02:09The rugged turboprop is designed to land on shorter runways.
02:14Hawker Siddeley 748 was one of a number of aircraft built to replace the DC-3 as a commuter
02:21slash cargo slash military type aircraft, but primarily used as a commuter aircraft.
02:30It's the ideal plane for a regional airline that connects big cities to small towns in
02:35Illinois.
02:36Illinois 710, radar identified.
02:37Continue to 3,000 feet.
02:38Clear to Carbondale.
02:39Illinois 710, radar identified.
02:40Continue to 3,000 feet.
02:41Clear to Carbondale.
02:42Cleared to Carbondale.
02:43Illinois 710.
02:443,000 feet.
02:45Cleared for Carbondale.
02:46Thank you and good night.
02:47Heading 175.
03:01Less than two minutes after takeoff.
03:03It's the generator again.
03:06A generator warning light comes on.
03:10The aircraft is equipped with two nine kilowatt generators that supply power to the battery
03:15banks and electrical systems.
03:18One of the generators has failed.
03:22Isolating it now.
03:25The first officer disconnects the right generator to protect the rest of the aircraft's electrical
03:30system.
03:33When something like this happens and you have a generator failure, one of the most important
03:38steps is to disconnect that generator from the system as quickly as possible.
03:46Janine Urban is a former Air Illinois pilot who landed the plane in Springfield three
03:51hours earlier.
03:54The generators are each rated to be able to carry the entire load.
04:01So if one generator goes down, you can continue to your destination.
04:07It is not an emergency.
04:11Tonight's 40-minute flight is taking seven passengers 146 miles from Springfield to Carbondale,
04:17Illinois.
04:18Springfield.
04:19Illinois 710.
04:20We've experienced a slight electrical problem.
04:21We'll keep you advised.
04:22Illinois 710, do you intend to return to Springfield?
04:23Negative.
04:24Continuing to Carbondale.
04:253,000 feet.
04:26The captain decides it's safe to continue the flight.
04:40I understand you are continuing to Carbondale.
04:43Roger.
04:45There's dense cloud cover this evening.
04:51The conditions at Carbondale were what is called IFR, instrument flight rules.
04:56They would have been operating in the clouds, needed their instruments to be able to fly
05:02the airplane.
05:04They were flying into deteriorating weather conditions.
05:08It's something that every airline pilot is trained to handle, but it doesn't give you
05:12much room for error.
05:17Four minutes after takeoff, the first officer checks the status of the generators.
05:23Zero voltage and amps on the left side.
05:26He discovers that the left generator is dead.
05:30The right generator is putting out 27 and a half volts.
05:34The right generator now appears to be working, but the first officer is unable to reconnect
05:39it to the electrical system.
05:41Can't get it to come online.
05:43The right generator is as good as dead.
05:47With both generators out, all the systems are feeding off the batteries instead of the
05:52generators.
05:53It's not a good situation.
05:58The aircraft has four nickel cadmium batteries.
06:02With no generators, the batteries are now powering lights, instruments, navigational
06:07equipment, and everything in the passenger cabin.
06:11How are the bats there?
06:19We're down to 22.5 volts.
06:22So now that we're operating on only battery power, the primary problem is that the batteries
06:28are only designed to operate for about 30 minutes under the best case scenario.
06:36Illinois 710 is now 32 minutes from its destination.
06:41If they don't reduce the drain on the batteries, it will be almost impossible to land without
06:47lights, instruments, or a radio.
06:51Okay, beacon's off.
06:55Okay.
06:56Nav lights are off.
07:00Are you using these lights here?
07:03I'll get that one down.
07:08The pilots quickly shut down non-essential systems.
07:13The sooner they start shutting things down, the longer the battery is going to last.
07:18How are the batteries?
07:22Pretty good.
07:23We're at 21.5.
07:27The efforts to conserve battery power seem to be paying off.
07:32We should last to Carbondale.
07:35Yeah.
07:38Midway to their destination, the weather deteriorates.
07:45The weather that Frank and Les encountered trying to get down to Carbondale was much
07:50stormier than Springfield.
07:53There were level two and three thunderstorms.
07:56Want me to tune into CAVI real quick?
08:00Sure.
08:01I'm not going to use that much power.
08:06Forty-five miles from Carbondale, the crew tunes into a signal that will provide a precise
08:10bearing to the airport.
08:14Meanwhile, air traffic control transfers the flight to the approach frequency for Southern
08:20Illinois.
08:23Air Illinois, Flight 710, contact Kansas City Center on frequency 125.3.
08:2825.3, roger.
08:30Air Illinois, 710.
08:36They were getting close to the airport, and that approach control facility would have
08:41lined them up for an instrument approach.
08:47After contacting approach control, the situation worsens.
08:53I don't know if we have enough juice to get out of this.
08:56The radios and transponder on Flight 710 have shut down.
09:02The pilots are now on their own.
09:08Illinois 710, I've lost radar contact.
09:12Flight 710 has disappeared from air traffic control's radar.
09:16Illinois 710, Kansas City.
09:20They had no capability at this point to get help.
09:26It was probably the most sickening feeling for both of them that you or I could imagine.
09:35Watch my altitude, going down to 2,400 feet.
09:41Concerned their instruments are about to fail, the captain attempts to get below the clouds.
09:49He was desperately hoping that he could see the airport beacon or some runway lights and
09:55land that airplane visually.
09:58Just eight minutes from landing...
10:00You got a flashlight?
10:04Yeah.
10:05The batteries are almost depleted.
10:07Here we go.
10:08You want to shine it up here?
10:10Trying to illuminate the instruments with a flashlight and a dark cockpit, that is very
10:15abnormal.
10:16And is he pointing at an instrument that's functioning or one that's not?
10:22We're losing everything down to 13 volts.
10:26Watch my altitude, Frank.
10:28It would have been a total panic situation in realizing that they were out of options.
10:38Okay, 2,400.
10:47Only losing electrical power and operating in total darkness, the pilots of Illinois
10:53Flight 710 desperately try to land their plane.
10:59The conditions at Carbondale were such that one mile visibility and light rain and fog,
11:04his chances of seeing anything were minimal at best.
11:09Do you have any instruments?
11:13Do you have a horizon?
11:18They're in a dark cockpit.
11:20Instruments are failing.
11:21They can't see anything outside.
11:23They were now into a critical emergency.
11:26Okay, you're banking left, six degrees.
11:30Okay, correcting to the right.
11:37A little more.
11:58Illinois 710, Kansas City, do you read?
12:01I would be very surprised if they knew that they were going to hit.
12:04I would be very surprised they saw the ground at all.
12:09Air Illinois Flight 710 crashes 25 miles north of Carbondale Airport.
12:17The wreckage is scattered across farmland near the town of Pinckneyville.
12:23All seven passengers and three crew members are dead.
12:32The National Transportation Safety Board, or NTSB, begins an investigation to determine
12:37what happened to Flight 710.
12:41Let's see what we got here.
12:45They begin by reviewing the debris pattern.
12:53It's a half a mile long and roughly 200 feet wide.
13:03Investigators get a sense of the vast impact area, which extends across two small wooded
13:08areas, a field and a pond.
13:11They came in at a shallow angle.
13:14The wreckage pattern gave us the idea that this was a fairly high speed, low angle impact
13:21to be able to spread the wreckage like this over a half a mile.
13:27First point of impact is right here with ground scars and debris heading north.
13:36Carbondale Airport is 25 miles to the south.
13:41Investigators determined that at the time of the crash, Flight 710 was flying in the
13:45opposite direction to its destination.
13:49With the aircraft traveling the way it was at that speed and in a wrong direction, it
13:55made us wonder, was the aircraft actually under control?
13:59So first ground scar here, followed by a few more, and then 200 feet in front of that,
14:09the right wing tip.
14:12Near the first impact marks, investigators discover fragments of a green navigation light
14:18from the plane's right wing tip.
14:20It was banked to the right when it hit the ground.
14:24We had the right wing tip.
14:26We knew that was the first thing that hit the ground, and we could measure approximately
14:3030 degree right bank.
14:34Did the crew report any issues to air traffic control?
14:37Yeah, they did.
14:40Springfield, Illinois 710, we have experienced a slight electrical problem.
14:48We'll keep you advised.
14:51Investigators learned that 90 seconds after taking off from Springfield, the crew reported
14:56an electrical problem.
15:00Anything else?
15:01That's it.
15:03Just the electrical problem.
15:07We'll need to take a good look at all the electrical components.
15:11The pilot reported a slight electrical problem, and it was up to us to figure out what his
15:17problem was and why they crashed.
15:26Is this everything?
15:29Investigators examine electrical components for evidence of malfunctions.
15:35The wires are clean.
15:37There's no short circuit.
15:45This inverter's in bad shape.
15:50Hard to tell if they were working or not.
15:54What about the batteries?
15:59Four NICAD batteries are powered by two generators.
16:04Each battery contains 18 individual battery cells.
16:09No signs of arcing or short circuit as a result of impact.
16:14We were able to recover a total of 10 cells from the batteries, and they were all in decent
16:19shape.
16:20Well, let's see if they can hold a charge.
16:24Under normal conditions, the battery should be fully charged.
16:29Wow, they're dead.
16:34The batteries were able to hold a charge, but for some reason, they were run down.
16:42Did the generators malfunction and fail to charge the batteries?
16:46Is that the left generator?
16:52Lift engines power a generator shaft to rotate a metal core wrapped in copper coil.
16:59This is known as an armature.
17:02The armature spins rapidly between the poles of a magnet to generate electricity.
17:11Banding wires come off.
17:14Banding wire is used to hold the armature together as it spins inside the assembly.
17:20If the banding wire comes loose, the armature could jam.
17:31Soldering is melted.
17:34The motor must have overheated.
17:38Investigators discover evidence that the left generator failed.
17:43This happened before the crash.
17:47We know that there was no fire on the aircraft, so we believe that the solder melted due to
17:53internal heating, but we don't know why.
17:58They then inspect the right generator.
18:01The banding wire is intact on this one.
18:05Looks fine.
18:08We did a resistance test, checked the brushes, and we looked at all the mechanical workings
18:12of the generator.
18:13We were not able to find any reason why the right generator would not charge the batteries.
18:19How did they crash with four working batteries and one working generator?
18:25From examination of the wreckage, we were not able to find any reason for the accident.
18:33We were hoping that the voice recorder would give us clues as to what really happened.
18:46The recording starts around four minutes after takeoff.
18:52Investigators turn to Flight 710's cockpit voice recorder to determine how an aircraft
18:57with one functioning generator crashed short of its destination.
19:08Zero voltage and amps on the left side.
19:15Just like we suspected.
19:18The CVR recording confirms that the left generator failed shortly after takeoff.
19:25The right generator is putting out 27.5 volts, but I can't get it to come online.
19:33Investigators can't understand why the right generator was disconnected from the electrical
19:37system if it was operational.
19:41Then they hear an astonishing statement from the first officer to the captain.
19:46When we lost the left one, I reached up and shut off the right generator because I assumed
19:50the problem was the right side.
19:54Isolating it now.
19:58There are two shut off switches for the generators.
20:01One for the left generator and one for the right.
20:05The first officer disconnects the right one to protect the rest of the aircraft's electrical
20:09system.
20:13But he soon realizes that it's the left one that has the issue, not the right.
20:20Why doesn't he just reconnect it?
20:23He tries, but it doesn't work.
20:26The right generator was not charging the batteries, so that we know all they had to power the
20:31aircraft was the charge remaining on the battery shortly after takeoff.
20:37Maybe there was a problem with the switching unit.
20:40If the generator switching unit is not working, then the generator will not come back online.
20:44So we were quite interested in learning what we could about this component.
20:49It's in pretty rough shape.
20:54Looking for signs of a malfunction, investigators examine the right generator control switch.
21:01I can't tell a hundred percent.
21:07It's possible it failed before the crash.
21:11The switching unit was heavily damaged from the crash.
21:14We were not able to determine if that's even why the generator would not come online.
21:21Even if the switch was broken, it doesn't explain the pilot's actions.
21:29The first officer says, I assumed the problem was with the right side.
21:34Why would he assume something like that?
21:37Made us wonder if there was a problem with that generator in the past.
21:42Take a look at these maintenance reports.
21:45The team reviews the maintenance records for the Hawker Siddeley's generators.
21:50Check it out.
21:51No less than eight separate pilot complaints and repairs on the right generator.
21:55There were voltage fluctuations, recurring problems with the regulator, causing the right
22:03generator to shut down.
22:08Two weeks before the crash, there were issues with the right generator almost every day.
22:14They were doing maintenance, they were troubleshooting it, they were changing parts and they couldn't
22:19fix it.
22:21Air Illinois had one Hawker Siddeley and three flight crews flying that plane.
22:28I'm sure that they all knew that the right generator had had problems in the past and
22:32they probably all experienced it at one time or another.
22:36The first officer had been on some of those flights where the right generator had actually
22:42disconnected.
22:43Thank goodness, I was not.
22:46The most I ever saw it do was flicker a time or two.
22:50That would explain why the first officer disconnected the right generator instead of the left one.
22:59Investigators suspect that on the night of the crash.
23:02It's the generator again.
23:05The first officer made the immediate assumption that the right generator had malfunctioned.
23:12The reaction that the first officer had about taking the right generator offline probably
23:16falls into a phenomenon that's called expectation bias.
23:20He has experienced this in the past and assumed that that was going to be the problem without
23:27really looking at the indications he had available to him.
23:31Still doesn't explain the crash.
23:34Even though both generators were offline, investigators know the aircraft's batteries
23:39were in working order.
23:41How are the batteries?
23:44Pretty good.
23:45They're at 21 and a half.
23:49Should last to Carbondale.
23:51Yeah.
23:52It was really important to know, did the batteries have enough endurance to get to the airport?
24:04Let's see how they manage their battery power.
24:08Investigators returned to the cockpit voice recorder to determine why flight 710 ran out
24:13of battery power before reaching Carbondale.
24:15How are the bats there?
24:22We're down to 22.5 volts.
24:24Okay.
24:25Beacon's off.
24:27Okay.
24:29Nav lights are off.
24:34Just minutes after discovering both generators are down, the pilots turn off non-essential
24:39systems to save their batteries.
24:44They were doing the right thing, turning things off to reduce the load.
24:49But is it enough?
24:53According to the manufacturer, they needed to reduce their load to 70 amps.
25:00Amps measure the strength of an electrical current.
25:02The more amps drawn on a battery, the faster the battery will discharge.
25:09If the crew would have reduced the load to 70 amps, that would have given them a minimum
25:13of 30 minutes of endurance.
25:15That might have been enough time to get them to the Carbondale airport.
25:18Let's see if they got their load down to 70 amps.
25:24Well, we know they turned off the beacons, navigation lights.
25:31These make an inventory of the instruments the crew turned off and what they left on
25:36in order to calculate the load on the batteries.
25:41What else?
25:42Are you using these lights here?
25:47I'll get that one down.
25:49We were not able to determine what was powered up or on or off based on the flight recorder.
25:56We should have lost the Carbondale.
25:58So we had to rely on the conversations between the two pilots, what to leave on and what
26:03to turn off.
26:04Want me to tune into Cabby real quick?
26:07Sure.
26:08I'm not going to use that much power.
26:12DME instruments, weather radar, main cabin lights, one of the main radios, cooling fan,
26:26and the transponder.
26:28The weather radar and the radios draw a lot of power.
26:32And so shedding those, if you can, is a prudent thing to do.
26:36It looks like they kept the rest of the flight instruments on and that's it.
26:46They used 110 amps.
26:49Investigators discover the crew did not properly reduce the draw on their batteries.
26:55No wonder they didn't make it to Carbondale.
26:59This importance with load shedding and getting down to 70 amps seems to be lost on the crew
27:05as there seems to be no discussion whatsoever about amperage to determine if their changes
27:11in the electrical system were actually making a difference in the longevity of the batteries.
27:18So why did the pilots believe they had enough power to reach their destination?
27:25The team checks to see how the pilots monitored the state of their batteries.
27:30Says here fully charged.
27:31The batteries are 24 volts.
27:35Let's see how they did.
27:36How are the bats there?
27:45We're down to 22.5 volts.
27:50Eight minutes into the flight, they used up 1.5 volts.
27:57Seven minutes later, how are the batteries?
28:02Pretty good.
28:03We're at 21 and a half.
28:06The battery charge drops another volt to 21.5.
28:14The first officer says the battery should last to Carbondale.
28:20They're halfway through the flight.
28:21He's feeling good.
28:23And then nine minutes later, he checks again.
28:26It's 20 volts.
28:34So they think they're doing all right.
28:36And then minutes later, the radios go dead.
28:43We're losing everything down to 13 volts.
28:47They're talking about having 20 volts, and then they all of a sudden they have 13 volts.
28:54So they're monitoring the volts, but it's as if the sudden drop caught them by surprise.
28:59The reason this is significant is because NICAD batteries will maintain their voltage
29:05almost right until the end that the batteries are dead.
29:09Much different than lead acid type batteries, which is where you see a gradual decline in
29:15voltage.
29:18That characteristic of NICAD batteries may explain why there was such a sudden drop in
29:23the battery voltage.
29:26I don't know if we have enough juice to get out of this.
29:30If they would have known the characteristic of a NICAD battery, it might have sent them
29:34a message saying, we better get on this right away and get this load reduced.
29:40Investigators find another reason why the crew may have missed how fast their batteries
29:44were discharging.
29:47They never mentioned their amps.
29:50Looks like the only thing they monitored were the volts.
29:55Volts measure the potential output of a battery, not how long it will last.
30:00Amps tell you how much electricity is being drawn.
30:04It was very surprising that they weren't monitoring the amperage because that was going
30:07to tell them how much longer they had on the batteries.
30:12Did the crew have the proper training to monitor the endurance of the batteries?
30:23Investigators interview other Air Illinois pilots.
30:26So what'd you find out?
30:27How could NICAD determine their ability to monitor and calculate battery endurance?
30:32Well, we know that they were all trained on battery management for a dual generator problem.
30:39But when I asked them how long they thought the batteries would have lasted on the flight,
30:46some calculated 30 minutes, others, less than an hour.
30:52Flight pilots gave us five different answers and they were not all correct.
30:58It became obvious to us there was definitely a training issue involved here.
31:02Are you using these lights here?
31:05I'll get that one down.
31:08The lack of training explains why the pilots thought they had enough power to reach Carbondale.
31:14But that doesn't solve a bigger mystery.
31:20This is their flight path.
31:22Why didn't the pilots land the plane at another airport before completely running out of battery
31:27power?
31:28One, two, three, four, five different airports.
31:35They were only five minutes away from Swimmingfield, yet they elected to go 40 minutes to Carbondale.
31:40And there were several airports in between that they missed.
31:43They could have landed any time along the way.
31:47Their decision not to land calls the pilots' judgment into question.
31:52It's time to look into their backgrounds.
32:04Here's the captain's file.
32:07Investigators dig into the backgrounds of Flight 710's pilots for clues that explain
32:12their unusual reaction to an electrical failure.
32:18The captain was perfectly qualified.
32:22Same with the F-O.
32:23Gear up.
32:27The two pilots were among the most experienced flight crew in the roster.
32:31Gear is up.
32:32With a combined 5,000 flying hours between them on the Hawker Siddeley.
32:39Here's something.
32:41The captain lived in Carbondale.
32:45Maybe he wanted to get home?
32:47In aviation, what we describe as get-home-itis is when we try to make it to the destination
32:54because of our strong desire to do so.
32:58And it plays a significant role in our decision making.
33:03Investigators talk to other pilots at the company, including First Officer Janine Urban.
33:09How well did you know the pilots?
33:13I flew with the captain and I was good friends with the first officer.
33:19I thought very highly of the first officer, Frank.
33:24I knew the flight attendant, Barbie, and liked her a lot.
33:30It was a very emotional thing to hear that both of them had been killed.
33:37What sort of pilot was the captain?
33:40I'd say average.
33:44In the aviation community, when someone is characterized as an average pilot, that usually
33:48means he's not too good.
33:51Why's that?
33:52The captain really prided himself on getting there on time.
33:57It was not uncommon for him to take risks.
34:05Looks like we've got some weather.
34:06Shall I call for deviation?
34:07Doesn't look too bad.
34:10We'll be fine.
34:15According to air analog pilots, the captain would often fly too close or through dangerous
34:20storms to save flight time.
34:26If I made any comments or suggestions about a safety issue, like the thunderstorms or
34:34anything else, he would do something spiteful just to prove that he was the captain.
34:42In order to keep schedule, he'd also speed up, which would set off the overspeed alarm.
34:47Pull the circuit breaker, would you?
34:54What?
34:55Really?
34:56The pilot said he would order them to disable the overspeed warning so that they could fly
35:02faster.
35:05It was always about getting there faster.
35:10The captain's behavior is troublesome.
35:14We wanted to know if the company, the airline, was putting undue pressure on the pilots to
35:20make the schedule.
35:22This pressure to get there on time, was it from management?
35:26No, it was all the captain.
35:30The interviews with the other pilots indicated that there was no undue pressure to skirt
35:34the rules.
35:35In the case of the captain, that pressure was self-imposed.
35:40Investigators conclude that Captain Smith often stretched the rules.
35:45What about the first officer?
35:50Frank was the best, and he knew the plane and its systems really well.
35:58So why didn't the first officer speak up when Captain Smith made the decision to carry
36:02on?
36:03Illinois 710, do you intend to return to Springfield?
36:08Negative.
36:09Continuing to Carbondale, 3,000 feet.
36:13And at no time did we hear the first officer challenge the captain's decision to go on
36:17to Carbondale.
36:18We found this very perplexing.
36:20I asked how he could fly with the captain because he took so many chances.
36:25And he said, oh, I just try to keep an eye on the situation and not let him get us into
36:32anything that I can't get us out of.
36:35We're losing everything down to 13 volts.
36:38Watch my altitude, Frank.
36:40Boy, that didn't work out very well at all.
36:44The captain should have made the decision to return to the Springfield airport.
36:49And if so, none of this would have happened.
36:57Investigators conclude that the risk-taking captain and an unassertive first officer was
37:02a dangerous combination.
37:06Let's pick it up from where they realize they don't have enough power to make it to Carbondale.
37:11The team returns to the cockpit voice recording to see if they can uncover why the plane ended
37:18up so far off course.
37:21Watch my altitude.
37:22Going down to 2,400 feet.
37:26OK.
37:29Stop the tape.
37:31Why would the captain decide to drop down to 2,400 feet?
37:39The cloud ceiling near Carbondale was almost 2,000 feet.
37:43So maybe he was popping in and out of the clouds to see something on the ground.
37:49Play on.
37:53You got a flashlight?
37:55Yeah.
37:58Here we go.
37:59You want to shine it up here?
38:01Just as the captain tries to see the ground, the cockpit lights go out and plunge them
38:08into total darkness.
38:10We're losing everything down to 13 volts.
38:15Watch my altitude, Frank.
38:19OK.
38:212,400.
38:25They make it to 2,400 feet.
38:27The captain plans to level off, spot the runway, and continue his descent.
38:34But that's not what happens.
38:37OK.
38:37You're banking left.
38:39Six degrees.
38:41OK.
38:42Correcting to the right.
38:44Just minutes later, they ended up crashing in completely the opposite direction.
38:48A little more.
38:50So the question is, what happened?
38:59How do you go from leveling off at 2,400 feet to then hitting the ground
39:04in the opposite direction?
39:07Investigators examined the final moments of Flight 710
39:11to determine what ultimately brought the plane down.
39:15How does the recording end?
39:25The recording eerily slows down.
39:32And then, silence.
39:36Their batteries just died.
39:38Uh.
39:39The captain is asking for a horizon reading on the Attitude Directional
39:43Indicator, or ADI.
39:47The ADI uses an electrically powered gyroscope
39:51to indicate the aircraft's pitch and roll relative to the Earth's horizon.
39:56It's nighttime, no discernible horizon, low visibility.
40:02Your ADI is in the air.
40:04They've lost the lights on their instruments.
40:08Some of them are starting to fail.
40:12He asked the first officer to shine a light on their ADI.
40:19OK.
40:20You're banking left.
40:21Six degrees.
40:23OK.
40:24Correcting to the right.
40:25Just minutes later, they ended up crashing in completely the opposite direction.
40:29A little more.
40:30Just minutes later, they ended up crashing in completely the opposite direction.
40:35Investigators can only surmise what happened next.
40:39Even if all the instruments had failed,
40:41the ADI would still look like it's working.
40:46The ADI gyroscope spins at about 15,000 RPM.
40:51Even after the power shuts down, it will continue
40:54rotating for several minutes.
40:57So it looks like it's working, but it really is not.
41:01As the ADI winds down, it slowly tilts to one side.
41:06Imagine that ADI starts slowly falling to the left.
41:14And correct by rolling to the right.
41:19OK.
41:20You're banking left.
41:21Six degrees.
41:23OK.
41:24Correcting to the right.
41:27A little more.
41:30It may have appeared to them that the ADI was working correctly,
41:33but they're really banking to the right and losing altitude.
41:38They probably followed that failing ADI right into the ground.
41:46They couldn't see where they were.
41:47They couldn't see any lights.
41:49And it would be over in an instant.
42:01The ADI was still spinning at about 15,000 RPM.
42:05In their final report, investigators
42:08conclude that the fatal accident was
42:10a consequence of a captain's decision
42:12to continue the flight toward Carbondale
42:15instead of returning to the nearby departure
42:17airport after the loss of power.
42:21The cause of this accident was not a catastrophic failure
42:24that suddenly caused the airplane to crash.
42:27It was the decision by the captain
42:30to continue flight on battery power
42:33after they lost the generators.
42:36Also adding to the problem was a lack of crew resource
42:39management, or CRM.
42:42Now part of crew resource management training
42:46is that crews are trained to act as a team,
42:51and first officers are taught and encouraged
42:54to question the captain's decision making and actions
42:58if they do not agree.
43:00Speak up.
43:01Don't worry about if it upsets somebody's ego.
43:04It's not worth dying over.
43:07Investigators cite inadequate crew training
43:10to assess battery endurance as another contributing factor.
43:15It should have been discussed in their training.
43:18It should have been in their training materials
43:20and in the flight manual.
43:23As a result of this accident, the NTSB
43:26also recommends independently powered
43:28ADIs on all transport airplanes.
43:32So that if all power was lost, they still
43:34had the ability to keep the airplane straight and level
43:36for at least 30 minutes.
43:39This recommendation was implemented in 1997.
43:45Flight 710 brought national attention
43:48and increased scrutiny of small commuter airlines.
43:53Six months after the accident, Air Illinois
43:56filed for bankruptcy and ceased operations.
44:00It's something where we learn by our mistakes.
44:03The first priority is the safety of the passengers.
44:06It's got to be the most important factor.