The DEADLIEST CRASH of its time | Turkish Airlines flight 981

this video will include references to historical heavy loss of life so if you are a sensitive viewer please be advised it's the 3rd of march 1974. turkish airlines flight 981 a mcdonnell douglas dc-10 is climbing away from paris orly airport as the aircraft climbs through about 12 000 feet a sudden explosive decompression occurs as the aft cargo door rips off the aircraft now if you think that this sounds familiar it's because it is less than two years earlier the crew of american airlines flight 96 had defied all odds and managed to land their stricken aircraft after a very similar incident this time though the outcome is far more terrifying so what has actually happened this time are there parallels to the previous accident and if so how is that possible as always we will find the answer to that in the final report so please stay tuned [Music] it's impossible to tell you the story about turkish airlines like 981 without first explaining american airlines flight 96 okay these incidents are very very similar and i did a video about american airlines flight 96 just last week so i highly recommend you to check that out before you watch this video in summary american island flight 96 was also flown by a mcdonnell douglas dc-10 and when the crew departed detroit and climbed through a roughly 11 700 feet its aft cargo door ripped off the aircraft causing an explosive decompression and because of a lack of ventilation between the passenger cabin and the cargo hold part of the aft cabin floor collapsed in towards the missing door severely damaging the control cables to the horizontal stabilizer to the elevators rudder and the number two engine now through a combination of skill of both the flight crew and the cabin crew this aircraft managed after some severe difficulties to get down safely on the ground and everyone survived but in the case of turkish airline flight 981 it was to become the biggest single aviation accident in terms of human lives lost at its time so what are the differences between the two well first of all we have to look at what happened in the almost two years that separated the two accidents american airlines flight 96 happened back in june 1972 and in february 1973 the national transportation safety board came with their final report in the final report they had some quite severe remarks on the design of the mcdonald douglas dc10 it stated that the locking mechanism of the aft cargo door needed to get reinforcement specifically to the torque tube that connected the handle to the vent door in order to make sure that it couldn't be bent thereby making sure that the door handle could not be closed if the locks was not in the correct position in addition to that there needed to be some kind of verification procedure so that the person who was operating the door could verify that the locks had gone completely into position and also there needed to be increased ventilation in between the cargo holds and the passenger hold because of the position of the control cables in the flooring between the two compartments the rapid depressurization was not to be allowed to damage these critical control functions as soon as the federal aviation administration got a hold of this fine report they started to work on something called an aed right that's an air verdan's directive and an air vertex directive is the big hammer in aviation legislation okay if an airwardness directive is issued well then anyone who's flying the type of aircraft that you know is covered by the ad needs to essentially put it down on the ground and sort out whatever the issues are before they're allowed to continue to fly with it that's going to come with some really big costs for any airline who's flying that type was covered by the ad and it's going to be a huge embarrassment for the aircraft manufacturer and it might be because of that that the director of the douglas department in mcdonnell douglas came into contact with the faa administrator and the boatman sat down and came to what is known as a gentleman's agreement and in the gentleman's agreement the faa promised not to issue an awareness directive and in return mcdonnell douglas would make sure that any of the issues that was raised in the final report would be sorted through something called service bulletins with alert status now service bulletin is a less powerful tool than an ad while an ad would force anyone to generally sort the problems out immediately a service bulletin will give a little bit of leeway a little bit of time for any airlines to implement the corrections needed they are still powerful right especially if it comes with alert status which indicates that this has saved the implication any airline who doesn't comply with the safety bulletin would open themselves up to potential litigation in case something happened but it's not the big hammer very quickly after this mcdonnell douglas did issue three separate service bulletins for the dc10 the first one instructed airline to put in a kind of support bracket to hold the torque tube connected to the handle and because of that support tube it would be impossible to bend the tube and thus in theory making it impossible to close the door handle if the locks were not in the proper position the second one was an instruction to create about an inch big viewing hole in the door so that anyone operating the door could look through that viewing hall and see physically that the locks had gotten into the correct position the third service bulletin was to provide better electrical wiring to the electrical motor that was driving the locking mechanism to make sure that it wouldn't stop prematurely when it came to the part of the special report that mentioned the increased ventilation between the passenger cabin and the cargo compartment mcdonnell douglas hadn't found a proper solution to that yet so there was no service bulletin issued on that matter at this time the aircraft that was later going to become turkish airline flight 981 ship 29 was delivered to turkish airlines with paperwork stating that all three of these service bulletins had been properly implemented now in the subsequent investigations it was going to come to light that only one of them actually had been completed but we'll talk about that in a while turkish airlines flight 981 was scheduled as a two leg flight starting in istanbul and then about a four hour flight over towards paris orly airport and then a very short last leg over towards london heathrow on the first leg there was 167 passengers and 11 crew the captain of the flight is called neyat berkus is 44 years old has 7 000 hours in total of which 438 hours was on type at the day of the accident together with him was first officer oral ulusman 38 years old 5589 hours and 628 hours on type the flight engineer is called erhan archer 37 years old 2113 hours and 775 hours on type there were eight flight attendants from both the uk france and turkey on board the first flight was completely uneventful it left istanbul at 7 57 local time and landed about four hours later at 11 02 in paris orly local time now when it arrived to paris 50 of the passengers disembarked the aircraft and they boarded another 216 passengers this was quite unusual because normally this second leg was a little bit underbooked but because of some strike action happening passengers from both air france and british airways had been rebooked onto this turkish airlines flight to bring them over to london the turnaround was initially supposed to be only one hour but because of all of these extra passengers that was getting onto the aircraft they delayed the flight for another 30 minutes and while they were doing the turnaround they after cargo hall was completely emptied from cargo and there was no new cargo going into that compartment so it was closed there were three people working with emptying the aft cargo compartment and the person closing the door reported afterwards that he had no problems whatsoever closing the door there was no extra force needed to put the handle into place and he also said that he hadn't checked the little verification window that had been installed the reason for that was that no one had actually instructed him on why he should be doing it he didn't know what to look for he had only seen other people do it now next to the door handle after american airlines flight 96 they had been installed some notes instructing the people closing the door and how important it was to verify that this look was actually in place unfortunately though that note was written in turkish and in english and the person who was closing the door only spoke french so he never saw or understood the significance of this note at time 12 24 local time turkish airlines flight 981 received their pushback clearance and tackled the clearance out to holding position for runway 08 in orly during the taxi out everything seems to be normal the cockpit voice recorder is not indicating anything out of the ordinary and at time 1229 the aircraft started its takeoff roll initially the clearance was to climb to 4000 feet and then contact the departure controller the weather in the area was perfectly fine light winds from 0.60 degrees and only some few cumulus clouds around the departure was completely normal the aircraft climbed up to 4000 feet switched over to the departure controller and the new controller instructed the aircraft to continue the clamp to flight level 230 which is 23 000 feet and turn left to a vor navigation aid called montidiere mike tango delta the aircraft completes its turn towards montiria it rolls out on a heading of three five cylinder greaves which is roughly a noddly heading and continues its climb as instructed but as the aircraft climbs through about eleven 500 feet as sudden decompression can be heard on the cockpit voice recorder and it's also indicated on the flight data recorder the first officer is heard to call out the aircraft has burst and then a complete pandemonium starch okay the flight data recorder indicates that the aircraft is pushed into a left-hand yaw as the rudder is deflected towards the left the elevator is pitched down three degrees okay this puts the aircraft nose into a diving position and at the same time the number two engine starts to fail very similar to what happened in american airlines flight 96 in the air traffic control center in paris the air drive controllers can hear a transmission which is believed to come from turkish airline flight 981 the reason that they're not sure is because of the person that is holding the transmission button in the aircraft is not actually communicating with our traffic control they can hear voices in turkish that is talking about the severity of the problem that they're facing they can also hear the cabin altitude alarm in the background as well as the overspeed alarm this transmission goes on for several seconds it will also be following two more transition in the coming 70 seconds which is left of this flight at the same time the controllers are looking at both their primary and their secondary radar the secondary radar is the one that gets information from the aircraft transponder and around about when the first transmission is coming from the aircraft the code of the aircraft disappears from the secondary radar but on the primary radar the controllers can still see what now appears to be two different radar echoes so the first one is representative of the aircraft which continues up in a northerly direction turning slightly toward the left but the secondary echo stays approximately at the same place and remains for about a minute or two before it disappears from the screen subsequent investigations will show that as the aft cargo door once again opened in flight and got ripped off the aircraft this time the passenger cabin floor in the back part of the aircraft collapsed in a much more catastrophic way and two rows of passengers actually got pushed out through the open cargo compartment and it is likely that that secondary radar echo that the air traffic controller saw was actually this happening the aircraft finds itself in a dive almost 20 degrees nose down and that is a horrific attitude okay as this is happening the aircraft's speed is increasing to 360 400 and subsequently 430 knots the speed is increasing the way aircrafts are built is that if they don't have any kind of control inputs the stability of the aircraft will return the nose into an almost level position and this is what seems to happen on this flight as well it the nose subsequently increases from a minus 20 degrees pitch to about -4 degrees pitch the speed stabilizes around 430 knots but even though the pilot seems to have control of their ailerons there is no control and pitch in this case so the aircraft will actually continue to fly for another approximately 15 kilometers before it impacts the forest of ermenoville which is about 37 kilometers north east of paris the aircraft initially makes contact with the tops of the trees in a about four degree descending angle and a slight left-hand turn and subsequently it slams into the ground with almost 800 kilometers per hour because of that speed and the force of the impact the aircraft is shattered into thousands of small fragments and there's no fire breaking out just because of the sheer force of the impact [Music] obviously this is a non-survivable event and all 346 people on board are killed instantly making this the most deadly aviation disaster at that time now the investigation kicks in and among the debris field they managed to find both the cockpit voice recorder and the flight data recorder which greatly helps the investigation also in a field about 15 kilometers earlier just under where the initial incident happened they find the bodies of six passengers still strapped to their seats and what's left of the aft cargo door and when they're starting to look into the cargo door they immediately recognize the similarities with the accident two years earlier of american airline flight nine six because as they're looking into the lock mechanism they see once again that the four main locks are not properly engaged they have partially engaged but they haven't achieved the over center position which makes the whole locking mechanism irreversible but how is that possible there was three separate service bulletins that were in force in order to stop precisely this from happening well as the investigators continued to look into the door they realized that even though the aircraft has been certified as all of these three safety bulletins have been completed they haven't been in fact the support bracket that is supposed to hold the upper torque tube and support it to make sure that it can't be bent has not been installed at all there is some indication that work has begun on the door but it has never been completed and when they continue looking down onto the locking mechanism they look at the locking pins the way that locking pins are supposed to work is that as long as the locks are not completely in position the locking pins are hidden behind a couple of metal flanges so if you try to close the door handle with the locking pins behind those the the flanges will basically stop the mechanism from moving and making it impossible to close the door but on the accident aircraft it looks like these looking pins have been manually adjusted and they're now about eight millimeters shorter than they should be and what that means is that as the door handle is being closed the locking pin does come into contact with the back side of the metal flange but there is a very little margin and that margin can be overcome by the whole mechanism bending and because the support bracket has not been installed that torque tube once again is allowed to bend making it easy to close the door only about 50 pounds would be needed in order to close the door and this climbed up with the ground handling agent who said that he didn't feel that he needed to use any excessive force more than what he was used to to close the door handle another adjustment that is found is that the lock indication mechanism that is supposed to send the signal up to the cockpit indicating when the doors are properly locked has also been adjusted so in the position that it's found the door locked light would have gone out before the lock comes into its properly closed position now the ground handling agent would have been able to stop this sequence of events if he had been properly trained to actually check that the locking mechanism had engaged properly but he hadn't been trained and in fact on a regular basis it would be the uh ground engineer of turkish airlines who should be doing the walk around and verify that these locks were in place but he was not on duty on that day so as you can see guys as is the case with so many of these accidents if any one of these factors would not been in place it would have stopped the sequence of events that led up to the disaster if the ground service agent had checked through the viewing hall and verified that locks were in place he would have seen that they weren't and it would have stopped it if any one of the service bulletins that were in you know implemented in order to keep this from happening would have been properly implemented it wouldn't have happened either but because that wasn't the case the aircraft proceeded with taking off with locks not properly engaged and as the differential pressure inside of the cargo hold started to rise so did the pressure on the cargo door if the cargo door wasn't properly locked that pressure would have been routed on towards the stops which it was designed to do and nothing would happen but because the locks were not properly engaged all of this force was now transferred onto the bolts that held the mechanism in place and when the force became strong enough it sheared off those balls opening the door and enabling the disaster and this happened at around 12 000 feet which is almost exactly the same altitude as it happened on american airlines flight 96 but why did this dc-10 end up in such a huge disaster when the american airlines flight 96 managed to land the aircraft safely well the answer to this likely lies in the load of the aircraft because the american airlines flight 96 only had about 56 passengers on board and in the aft part of the cabin they had a lounge area and a small bar but turkish airlines flight 981 was a completely full aircraft right it was 346 people on board which meant that as the cargo door opened and the depressurization happened there still wasn't enough venting leaving the air from the passenger cabin anywhere to go in order to equalize the pressure difference between the cargo hold and the passenger cabin this put an enormous amount of pressure onto the floor a pressure that the aircraft was not designed to take and because of the extra load all of the passengers sitting on top of the floor it is likely that the floor at the back of that dc-10 completely collapsed severing all of the control cables to the elevator to the stabilizer to the rudder and to the engine number two if all of those cables were severed it would have left the aircraft completely without any control in pitch while in the american airlines flight 96 the floor only partly collapsed enabling the aircrew to still have some control of their aircraft this is likely the reason for the difference in outcome between the two accidents in the aftermath to this horrible disaster there were several large lawsuits filed and during the discovery in those lawsuits there were papers found from an employee at convair one of the subcontractors to mcdonald douglas his name was dan applegate now dan applegate had in the wake of american airlines flight 96 issued a memo to his bosses where he said that he was concerned about the degradation of the safety around the aft cargo door and he said that the american airlines flight 96 indicated that the design changes that had been made had compromised the safety of the entire system and it was likely that this would lead to a whole loss during the coming 20 years of the aircraft's normal lifespan he also pointed towards a pressurization test that had taken place back in 1970 where the first dc-10 airship one had been pressurized during a test and the forward cargo door had blown up causing the passenger floor to collapse now this memo is referred to in history as the apple gate memo and unfortunately it was never acted upon and the reason why it wasn't acted upon is still a little bit of a debate but what we do know is that convair as a subcon contractor the ones that were responsible for building the door they were not allowed to contact the faa themselves instead they should bring any concern they had up to mcdonald douglas who would then bring it to the concern of the faa but because there were some discussions going on between convair and mcdonnell douglas about who would bear the responsibility of a complete redesign of the cargo door this discussion seems like it never took place after this there were some serious disputes between mcdonnell douglas and turkish airlines about who was actually the responsible party for the crash but because of the findings and in part due to the dan applegate memo they decided to settle the lawsuits for at the time a record amount of money the fund report came with several safety recommendations because of this accident including the reiteration of the findings that was made in the american airlines flight 96 funnel report they also said that particular attention should be put to the cargo door closing and locking and the behavior of flooring in the case of a sudden depressurization of the cargo compartment they also pointed out that flight controls and wires to the flight controls needed to protect it as well as the redundancy of those systems but probably the biggest point they made was that there hadn't been a air boardness directive issued and they said that in subsequent cases when there was any risk of safety being compromised an air worthiness directed had to be used no matter what the financial implications of that ad might be and this is something that the industry lives by until this day after the disaster of turkish airlines flight 981 the latching mechanism for the cargo doors of the dc-10 was completely redesigned the new design made sure that the mechanism wouldn't stop until the latches were in their perfectly closed position also it connected the locking pins to the vent door making sure that the only time the ventor would be closed and enable pressurization of the cargo compartment was if the locking pins were in the correct position also the faa mandated all jumbo jet operators not only the dc10 but also the lockhead 1011 and the boeing 747 to cut proper vents in between the passenger compartment and the cargo compartment making sure that a rapid depressurization would not cause a failure of the cabin floor and wouldn't affect any of the flight control cables in the case of the dc-10 this meant stiffening up and reinforcing the whole floor of the passenger compartment i hope that you guys are finding the series about aviation accidents and investigations fascinating and if you do there is a playlist up here with many more that i've done before i also hope that i have earned a subscription from you and if you have subscribed to the channel make sure that you highlight the little notification bell so that you know if i do maybe a spontaneous video about current events or a reaction video and they might not always happen on fridays now i love hearing from you guys so if you have suggestions to videos i should be doing or accidents i should be covering or anything else that i should be explaining then let me know in the comments below and if you want to hang out with a really seriously nice crew of aviation interested people will then get either the free mentor aviation app or join me in my discord server we do some really really fun stuff in there including aviation quizzes and we share photos with each other and we just talk about aviation if you want that there is a link to both the app and the disco server in the description below have an absolutely fantastic day and i'll see you next time bye [Music] you

Channel: Mentour Pilot

Views: 847,668

Keywords: air crash investigation, air crash investigation 2021, air crash documentary, aviation accidents documentary, mentour pilot 737 max, mentour pilot crash, aviation incidents, aviation incidents and accidents, turkish airlines flight 981, turkish airlines flight 981 air crash investigation, turkish airlines flight 981 documentary, Fear of flying, Fear of flying help, Pilot life, dc 10 crash, DC10, mcdonnell douglas, mcdonnell douglas dc-10, american airlines flight 96, NTSB

Id: _7rF0wCSpE0

Length: 28min 3sec (1683 seconds)

Published: Fri Mar 26 2021