- vor 22 Stunden
On 21 January 2019, a light aircraft breaks up in mid-air and crashes into the English Channel off Alderney in the Channel Islands during a flight from Nantes, France, to Cardiff, Wales. Argentine soccer player Emiliano Sala and pilot David Ibbotson are both killed.
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00:00the pilots of air transport international flight 782 prepare to depart from kansas city with just
00:09three of their four working engines a three-engine ferry it's a difficult maneuver a hundred knots
00:16okay their takeoff goes tragically wrong we're off the runway go max power you got it
00:24this accident of course was very tragic and they did not make it examination of the wreckage reveals
00:33very little stem to stern wingtip to wingtip was airworthy but when investigators visit the
00:38simulator used to train the pilots this is not how their aircraft would have behaved they begin
00:43to understand the origins of this accident the simulators are extremely accurate we were shocked
00:50that this one was not
01:04okay first things first let's review our three-engine ferry procedure sure thing yep
01:27air transport international flight 782 has been cancelled one of its four engines won't start
01:35maintain directional control using rudder and nose wheel steering the replacement crew is taking
01:42the cargo plane for repairs to a maintenance facility in massachusetts the only crews that are permitted to
01:48do a three-engine ferry are the very experienced crews because it is very dangerous it does not happen
01:54very often captain walter meager has worked his way up from flying the dc-6 and dc-7 and is now captain
02:02on the airline's dc-8 aircraft the captain had about 4 000 hours in the dc-8 he'd been flying the dc-8 for
02:12years max went for takeoff crosswinds 10 knots tailwinds five knots okay let's check the weather on that
02:20first officer mark alma is new to the company and the plane but he's been flying for 14 years
02:28he only had about 200 hours in the dc-8 however uh he was commended for being enthusiastic for trying
02:35to learn and being an important part of the crew there's a third crew member on board flight engineer
02:42kerry hardy flight engineer had more than 4 000 hours of flight time and in large airplanes
02:49he was a very experienced pilot it's a two-hour flight from kansas city to chicopee massachusetts
02:57where the engine is to be repaired here you go thank you the crew has concerns about their schedule
03:10there is a curfew on the airport in massachusetts the airline had told the crew that they needed to
03:15land by 11 pm because that is when that airport would close what we're going to need to do is get
03:23as much direct as we can that'll allow us to fly a little bit better than the 280 knots indicated
03:30well as pilots we're always trying to hurry the crew had decided that they wanted to fly a more
03:35direct route at a faster speed so we'll be using one nine right first officer alma wants the longest
03:43runway for their takeoff i'm going to request right because we'll get an extra 1300 feet okay
03:52in order to take off the dc-8 needs power from at least three of its four engines
03:59you always want the longest runway that you can get with a takeoff like this
04:03so that you have more room to get the airplane up to the proper speeds
04:07kansas city this is air transport 782 ready to taxi we're going to be a three-engine departure
04:17flight 782 checks with air traffic control about their runway assignment
04:22air transport 782 south on bravo taxi runway one left
04:26air transport 782 what's the winds winds 240 at four roger that's a tailwind right yeah you don't
04:42want a tailwind with a three-engine takeoff because it's going to take more runway 240 and we're running
04:48into what four four knots the tailwind was acceptable the maximum tailwind allowed was five knots and they
04:58had four knots flight 782 taxis to the longer runway take off data okay this is a max power takeoff
05:10the pilots review the required speeds for the three-engine takeoff okay i got vmcg of 107 123 for vr 140 for v2
05:20and 210 for the cleanup set this takeoff requires raising both inboard engines engine two and engine
05:29three to max power only when the plane reaches a certain speed can the third working engine engine four
05:36be increased to max power controlling the airplane on the runway while you are adding the power from
05:42the third engine is vital it must be done slowly and you must be able to keep control of the airplane
05:48at all times and of course we'll all be watching real close for loss of directional control
05:56two engines on the right side are going to cause the aircraft to veer to the left it's only going to have
06:02one engine operating on the left side so directional control is the critical issue on that three
06:08engine takeoff like this number one engine is inoperative so what we're going to do is set max
06:16power on number two and number three right right as the crew nears the end of the taxi they finalize
06:22the takeoff plan okay then i'll ease in number four and i'll call increments a point one yeah
06:32flight 782 is now ready for takeoff
06:41okay coming up on two and three
06:46the crew lets the inboard engines spool up before the plane starts moving set max power max power two
06:54and three
06:55at 8 20 pm air transport international flight 782 begins its takeoff
07:10one point three point four the flight engineer closely monitors engine power air speed's alive
07:161.6 80 knots 90 knots but 20 seconds into the takeoff roll the plane veers left of the center line
07:291.8 100 knots the captain uses his rudder to redirect the plane to the center of the runway
07:37but it doesn't work abort
07:44spoilers air transport 782 aborting takeoff
07:52flight 782 aborts its three engine takeoff
07:55air transport 782 roger when able turn right off the runway do you need any assistance negative
08:03assistance no negative negative assistance air transport 782
08:09the crew considers what went wrong
08:14we were at one six and then power went all the way up to one nine zero as you've ended up
08:17so it went up real fast and number four jerked up while i was trying to ease it in
08:24you brought it up too fast or it jerked up or what the power on it just came on too fast that's what happened
08:35hardy proposes a solution if you want to try it again i could try adding the power if you like
08:40okay let's do it that way it was decided that the flight engineer would help the captain and he would
08:50add the power on the third engine for the second takeoff tell him we want to taxi back and have
08:56another try at it kansas city ground air transport 782 we'd like to taxi back to depart one left again
09:04air transport 782 roger taxi one left okay
09:13while returning to the runway the crew revisits the takeoff procedure
09:17okay when do i have to have max power in on the outboard engine
09:23107
09:24flight 782 is again ready for takeoff
09:36kansas city control air transport 782 ready to go at the end of one left uh three engine takeoff
09:43air transport 782 heavy control one left turn right zero three zero clear for takeoff
09:50i've lined up just to the right of the center line here that's a good idea
09:58the captain did line up on the right side of the runway because
10:02they veered off to the left on the first takeoff and he wanted to give himself more runway width
10:08available in order to do the second takeoff okay make sure the two and three are set max power yeah
10:17at 8 26 in the evening flight 782 begins its second takeoff attempt one one one two
10:29one three one four
10:36one five one six
10:38air speed's alive 10 seconds into the takeoff roll the plane again starts veering to the left
10:52one seven
10:55the captain tries to direct it back to the center line with the rudder
11:03god bless it
11:08keep it going keep it going keep it going yeah
11:1280 knots 90 knots the captain attempts to get airborne
11:24we're off the runway but he doesn't have the speed go max power
11:29he tries to salvage the takeoff flight 782 is barely in the air
11:39get the nose down go max power you got it max power
11:54alert three runway zero one north end dc eight on takeoff
12:07air transport international flight 782 has crashed beside the runway at kansas city airport
12:15fire and rescue units are nearby on a night training exercise
12:19they rush to the crash site we heard a real loud boom like something hit the dock real hard take long
12:25for fire rescue crews to arrive in the scene i'm assuming no no just in a matter of 60 seconds
12:29all three crew members are dead
12:36the national transportation safety board or ntsb is notified and bob benzen is named lead investigator
12:43the aircraft had broken apart although it was in three large pieces
12:47a fuselage behind the wings seemed to be reasonably intact the wing assembly itself seemed to be in one piece
12:54the question benzen must answer why was the crew unable to execute this takeoff not once but twice
13:06we were aware that it was an attempted three-engine takeoff
13:09and because that is an unusual maneuver we wondered if that could have been
13:12part of the reason the aircraft crashed
13:16thanks for taking the time to meet
13:17while the plane wreckage is collected investigators speak to the controller to learn more about the
13:24crash when did you realize there was an issue with flight 782
13:30i guess the first thing that caught my attention was that they aborted their first takeoff
13:34why i was told the plane veered left on the runway and then they lined up for their next takeoff and
13:43the same thing happened only worse the plane veered left and this time they rotated awkwardly nose high
13:53there was a fire coming out of one of the engines and then there was a loud bang
13:56then the plane stalled rolled left and crashed
14:14a fire what side left that had to be engine number two
14:20plane engines are numbered from left to right for flight 782 the number one engine was inoperative
14:33if engine two failed the crew would be left with only the right engines
14:38we knew because this was a three engine takeoff attempt and if we'd lost any more power on the left
14:44side of the aircraft it may have caused an immediate crash
14:51what have you got investigators examine engine number two after its recovery from the crash site
14:59uh no penetration on the nose cowl fuel is present throughout
15:06compressor bleed valve is closed they discover that it was operative and it didn't fail on takeoff
15:12that fire in the engine was probably a compressor surge
15:20a compressor surge is a phenomenon that occurs when the tilt of the engine is is high enough
15:26that it disturbs the airflow going into the intake and causes a big bang flames coming out both ends
15:33perhaps but technically the the the engine isn't damaged at all
15:39so no unusual wear if all three remaining engines were working could one of the brakes have locked causing the plane to veer left
15:52treads look almost new no flat spots the tires show no sign of abnormal braking
15:58okay let's have a look at the brakes we thought that because they had aborted the earlier takeoff
16:09maybe they uh uh they use the brakes very heavily and caused them to uh fail frankly or weaken
16:18and then fail completely during the second takeoff
16:27brake sack assembly looks fine
16:31no discoloration or pitting on the pads
16:34discs are clean no signs of overheating
16:36we looked at brakes very carefully we found nothing really physically wrong there was no overheating or
16:46melting together so in in essence the the brake system did not become an issue
16:53the ntsb is still unable to determine why the crew lost control let's check out the rudder
16:59the rudder plays a massive role in a three-engine takeoff it is the key to keeping the airplane going
17:07straight and being safe three-engine takeoffs require the two inboard engines to reach vmcg or minimum
17:16control speed on the ground only then can the rudder counteract the directional force of the third working
17:23engine as it's powered up the faster you are going the more rudder control you have and you need that
17:32rudder control to be able to keep the airplane on the runway
17:41how's the rudder control cable look did the rudder malfunction causing the crew to lose control of the
17:47plane cable severed in several different places see there's no corrosion or fraying
17:53probably severed in the crash agreed let's test the rudder
18:00we looked very carefully at the cabling that we used in the rudder system
18:05and the only thing we did note were simple breaks in the cables because of
18:09overload instant overload which occurred during the crash control cable ready
18:16good to go if the rudder cables didn't fail then could the rudder itself have malfunctioned
18:23okay deflect left investigators test its movement turning to the left
18:33but the rudder moves freely we're good
18:38on occasion in previous accidents rudders have locked up or become blocked by some some broken part
18:45and we found that this did not occur during this this event the mystery of flight 782's crash deepens
18:54in the end we looked at the entire wreckage very very carefully from stem to stern wing tip to wing tip
19:04and determined that it was airworthy we had to look into other areas to determine what happened
19:11okay we found skid marks on the runway for the first takeoff starting here all the way to here
19:24then they aborted investigators now turned to evidence left behind by flight 782
19:30to determine why it veered off the runway in the second takeoff the skid starts even earlier
19:36here and the marks last
19:40till here
19:44skid marks were there indicating that although the aircraft was rolling forward
19:49it was skidding to the left side of the runway
19:52the skid marks are a telltale sign it looks like they had too much power to the right side of the plane
19:59and it happened early on look on both takeoffs they skidded to the left after only 500 feet correct
20:08so maybe there was an issue with the power in that third working engine
20:15let's find out we discovered that the engine operation would probably be some kind of an issue
20:21and the only way we could determine that was to go to the flight data recorder
20:27did engine number four somehow cause the plane to veer too far to the left
20:32there's the airspeed data there investigators examined the flight data recorder to learn how
20:40the crew managed their engines looks like we have a glitch here
20:46to learn more about how the crew manipulated the throttles
20:50we needed two parameters from the fdr airspeed and the engine pressure ratio or the epr we had airspeed
20:57but unfortunately this fdr did not record correctly the epr we need a workaround to get that engine data
21:07what about a sound spectrum analysis sure let's give it a shot
21:16okay coming up on two and three
21:17there's a microphone in the cockpit that records every sound and they can record and hear the engines as
21:31they are increased or decreased and they're very accurate
21:34the team conducts a digital analysis of the engine sounds
21:51done great work
21:55let's compare the third working engine engine four
21:59with the plane's overall airspeed data
22:01in the end we use both the fdr and the cvr to determine the airspeed throughout the entire flight
22:08and the power setting for all all three of the operating engines
22:17it looks like
22:20the third working engine engine number four almost reaches max power in 10 seconds when the airspeed is
22:26only about 65 knots
22:30that seems awfully slow
22:35was the power to engine four increased too soon in the takeoff roll
22:40let's check the three engine takeoff chart
22:44investigators examined the chart used by the crew to determine the speed they needed to reach before
22:49applying max power to engine number four
22:52what was their weight uh their weight was 220 000 pounds temperature is zero degrees
23:03they shouldn't have put the third working engine to max power until they reached 116 knots
23:08that's the target speed at 65 knots it was way too much power too soon
23:13one three one four one five one six airspeed's alive one seven investigators conclude engine four
23:28was powered up too fast pushing the plane to the left
23:37they never reached the speed they needed for the rudder to counteract the power of both engines on the
23:41right side of the plane
23:45that's why they veered off the runway
23:48why did the pilots increase power to the right outboard engines so quickly
23:56we knew that uh issue here was reaching vmcg at exactly the right time with the correct airspeed
24:03and everything but the crew didn't do that and that would became the big question why why didn't they do that
24:11whenever you're ready benzen's team listens to the cockpit voice recorder or cvr to better
24:20understand how the pilots of flight 782 performed the three engine procedure okay this is a max power
24:27takeoff speeds vr 123 140 and 210 vmcg of 107. okay i got vmcg of 107 vr of 123 140 for v2 and 210 on the cleanup
24:44both pilots think the vmcg is 107 knots should be 116. yep vmcg is 116 knots so how did the flight engineer
25:00get that wrong wait a minute check this out 107 is the speed for a temperature of 30 degrees
25:10celsius celsius
25:17investigators discover the flight engineer used the speed for a temperature of 30 degrees celsius
25:24but on the night of the crash it was 30 degrees fahrenheit approximately zero degrees celsius
25:33that c for celsius is so small he must have used 30 celsius thinking the chart is in fahrenheit
25:40they selected the wrong line to get their v speeds here you go thanks
25:54they were nine knots off on what vmcg should have been
26:05it's happened before four years earlier a flight engineer on another air transport dc-8 miscalculated
26:12the plane's weight providing the captain with the wrong takeoff speeds
26:17i was one of the first investigators from the ntsp to arrive on scene when i went into the cockpit
26:24it didn't take any smarts at all to see the takeoff data was 100 000 pounds too low
26:32and as a result the company very seriously began to emphasize the need to check those calculations and
26:38make sure they're accurate and so it's disturbing that in this accident that did not happen
26:43is that the only thing the pilots missed
26:56a question to consider captain
26:59once we get near vmcg if we've used all the rudder control you might want to consider abort
27:04because when we get higher we're going to be in worse trouble correct
27:07that's correct absolutely
27:12the cvr of flight 782 reveals that the captain and first officer were uncertain about the impact of vmcg
27:21speed on rudder control the first officer made the comment that you have the brother control is less
27:28effective once you go beyond vmcg when actually the opposite is true
27:37uh no actually the flight engineer realizes their mistake
27:42above vmcg rudder has more authority it's helping you more
27:46i understand
27:48but the captain fails to acknowledge the correction
27:50the flight engineer had the right answer that the faster the airplane goes the more effective
27:57the rudder becomes and you need that effectiveness to keep the airplane on the runway
28:02why didn't the crew stop and discuss it until they reached a consensus that's the advantage
28:09of having three people in the cockpit
28:13the right answer generally exists somewhere in the cockpit in this instance the flight engineer
28:18had the right answer maybe their lack of understanding about the procedure caused them to abort their
28:23first take-off it's possible
28:30here it is check that out
28:37power went all the way up to 190 as you ran it up
28:40so went up real fast and number four jerked up while i was trying to ease it in
28:45you brought it up too fast investigators learned that the captain struggled with engine four's thrust
28:52during the first take-off roll power on it just came on too fast it's what happened
29:01if you want to try it again i could try adding the power if you like
29:04the flight engineer proposes an unorthodox change to the procedure okay let's do it that way
29:10the flight engineer took over control of engine four that's crazy
29:20they couldn't have understood the difficulty the procedure if they split the responsibility
29:25the core problem is the captain could not tell how much rudder he was going to need because he
29:29wasn't the one adding the thrust to the airplane it's like trying to have two people drive a stick
29:35shift car one doing the steering one doing the shifting it just doesn't work you need to
29:40have one person in control at one time the flight engineer and the captain thought they could
29:48coordinate the takeoff together let's figure out how they did
29:56we worked with the douglas aircraft company and they produced a a graph of what an ideal three-engine
30:02takeoff should look like with airspeed and engine speed we compared that with what actually happened
30:10so this is what the crew was supposed to fly it seems like the power and speed rise steadily in
30:16unison until they reach vmcg very very smooth and synchronized but in the accident flight the flight
30:24engineer brings up power to the engine number four really quickly the plane begins to veer left off the runway
30:34then he brings down the power abruptly here probably in reaction to plane being out of control
30:44most probable thing we think happened was that the flight engineer saw the aircraft going off to the
30:50left of the runway and kind of panicked and tried to pull the engines back a little bit god bless you
30:56keep it going keep it going keep it going yeah instead of aborting the captain attempts to get airborne
31:07because they're about to veer off the runway he was countermanded by the captain who said don't
31:12nope keep going so the engines went back up we're off the runway go max power
31:21then the captain insists that he goes to max power a few seconds later they don't have enough
31:26speed for takeoff the captain never decided to abort and it appeared to be that he thought he could
31:33get the airplane in the air we will never know the captain and the flight engineer can never coordinate
31:43their actions one two one three why did the crew fail to execute a takeoff procedure that they were
31:56specifically sent to kansas city to perform you got it find anything investigators review the work
32:13history of flight 782's crew to determine their experience with three engine takeoffs
32:19our flight engineer and our first officer were new hires they were still on probation it's almost
32:26certain that neither had performed a three engine takeoff and the captain
32:36he'd done it three times but only his first officer he'd never actually flown as a captain
32:42they were all green the closest the captain came to flying this type of takeoff was in a simulator
32:52he only trained on it twice
32:58investigators traveled to colorado to assess the simulator the airline used to train its pilots to
33:04perform three engine takeoffs
33:06okay this is a three engine takeoff and we're watching for directional control
33:15did the pilots have sufficient training to perform this difficult procedure
33:20i'll call it engine power until you get to max part of the examination was to see if the simulator
33:25accurately portrayed what a three engine takeoff should entail okay let me give this a try
33:31engine two and three are spooled up engine four is set here we go
33:41slowly bringing up four
33:48one five one six
33:54one seven
33:54i am barely using my rudder there is no force pushing me off the runway
34:02one eight we have vmcg max powered engine four and rotate in the simulator the three engine
34:13takeoff is no different from a regular takeoff okay cut
34:17the simulator was not calibrated properly and that did not require the
34:25normal amount of rudder that would be required with a three engine takeoff
34:30this is not how their aircraft would have behaved not a chance
34:36simulators are for the most part extremely accurate and in this particular case we were
34:42frankly shocked that this one was not it also happened to be the one the crew trained on
34:49and this would really give them i think a false sense of security when it came to
34:54the difficulty of making a three engine takeoff i'm calling from the ntsb
35:00how did air transport international or ati compare to other cargo operators on three engine takeoffs
35:08i'd like to talk to your chief pilot we checked with the other cargo operators who were operating
35:14the gca there were nine of them it's only your most qualified pilots do it huh
35:21the vast majority of them used their most experienced crews
35:25and limited the operation to daytime and good weather now this led us to believe that the industry as a whole
35:33understood the danger and the difficulty of a three-engine takeoff better than ati did
35:41why did the airline choose such an inexperienced crew for such a difficult flight
35:46i think it's time we asked them that
35:50our team went to little rock which is the headquarters of the ati operation and we met with all of the key
35:56people there thanks for meeting with me so i've been told that you didn't use your most experienced
36:04crew why not i needed my experience crew for a revenue flight the flight 782 crew is only legal for
36:12a non-revenue flight how so they'd only had enough rest for a non-revenue flight
36:18you don't say they discover that the crew was selected because of a critical regulation governing
36:26non-revenue flights and rest times normal flights where the company makes revenue are covered by flight
36:33and duty time regulations for safety reasons they have to provide a crew that has been properly rested
36:40but there is a loophole that if the flight is not revenue then there are no flight and duty time
36:47regulations in theory a crew could fly in non-revenue flights indefinitely abort
36:57investigators now wonder how rested the crew was when flight 782 prepared for takeoff
37:04so take us through this investigators closely examined the crew of flight 782's recent flight
37:16assignments okay the morning before the accident our crew lands in germany after a seven hour flight
37:25from delaware
37:26and how many time zones did they cross six later that same day they return landing first in gander newfoundland
37:42and another flight to delaware so they cross another six time zones heading back
37:48we were aware that the circadian rhythm had to be pretty much out of sync
37:58it's simply not a good thing fatigue is not easy to recognize but it degrades all aspects of thinking
38:08decision making and performance they got into their hotel in delaware at 2 40 a.m on the day of the crash
38:15how much uninterrupted rest did the captain get
38:21less than five hours so they didn't have enough rest to fly anything except this flight
38:27and they were sent despite lacking the training and experience they needed
38:39the ntsb concludes its investigation outlining the fateful steps that caused the crash of flight
38:45782 it begins with the poorly rested crew
38:51one of the consistent findings of fatigue research is that people tend to underestimate how tired they
38:57are much of the time you can conduct a safe flight doing that but if something unexpected happens
39:05you're at a real disadvantage in this case the takeoff procedure was much more complicated than the
39:12crew had been trained to expect here you go thanks the flight engineer makes an error in a calculation
39:22that the other pilots don't catch once we get near vmcg if we've used all the rudder control
39:27you might want to consider abort because when we get higher we're going to be in worse trouble correct
39:30that's correct absolutely the pilots are confused about the takeoff procedure
39:38uh no actually above vmcg rudder has more authority it's helping you more
39:46this was a very delicate procedure and they seem to think otherwise
39:51if you want to try it again i could try adding the power if you like
39:53okay let's do it that way a decision to improvise a difficult takeoff
40:01leads to the plane veering out of control it was a very bad decision to improvise on this procedure
40:07because only the person operating the rudder can tell how effective that is when advancing the throttle
40:14okay the captain decides not to abort a second time
40:23the plane lacks enough speed to safely get airborne
40:28we're off the runway go max power
40:37it's hard to say what was going through his mind but i think he believed he could get the aircraft airborne
40:44in their report the ntsb makes several key recommendations one is to revise the training
40:50procedures for three engine takeoffs
40:55the crew not only was not trained well it was inexperienced in the particular maneuver they were
40:59talking about and uh they retired
41:04closing the loopholes that allow flight crews to perform non-revenue flights without adequate rest
41:10is another recommendation the reason this is relevant is because the company elected to have this tired
41:17crew fly the three engine ferry rather than the rested crew that was already present in kansas city
41:24it was legal but it was not a good idea the ntsb also recommends that three engine ferry flights be
41:33assigned to specially designated experienced crews training instructors advised pilots of the
41:40simulator's shortcomings for three engine takeoffs company exceeded the board's requests they really
41:46took it very seriously and did change their whole procedure to prevent this the airline industry as a
41:53whole does not follow suit non-revenue flights remain exempt from flight and duty time regulations
42:00there should be no difference with safety whether there are people on the airplane freight on the airplane
42:05or the airplane is empty one rest rule requirement should apply to everybody every time everywhere