Fatal Alarms - The Mystery of Birgenair Flight 301 | Mayday: Air Disaster

301 Santo Domingo a Boeing 757 disappears from radar with 189 people on board the plane's wreckage is soon found at Sea there are no survivors to say what happened this accident was the first major loss of a Boeing 757 aircraft investigators find no clues in the wreckage only the plane's Black Box can tell them what happened the tape raises a perplexing question indicator is not working what's happening how had the failure of one single instrument caused the crash of one of the world's most sophisticated jetliners [Music] Gregorio luperon International Airport in Puerto Plata the Dominican Republic February the 6th 1996 small Caribbean island is a popular winter getaway [Music] a group of German tourists has been delayed there are mechanical problems with the jet that were supposed to take them back to Frankfurt has arranged to lease another plane for the flight the replacement jet is owned by Turkish charter company Bergen air they have a 757 that's been sitting on the tarmac for almost three weeks but it takes several hours to get the plane ready to go and to get the Turkish crew aboard [Music] 15 p. m the plane and most of its crew are at the gate [Music] more than four hours after they were supposed to take off the first of the passengers begin boarding the plane they have a nine hour flight to Frankfurt ahead of them [Music] shortly after 11 30 Bergen Air flight 301 is given permission to leave the gate moments later it taxes to the threshold of the runway cabin crew take receipts ready for takeoff cabin announcement is completed first officer akud gergen is new to the 757 with fewer than 75 hours in the plane all in the last three months thank you ready for takeoff in contrast Captain Ahmed air dam is one of Bergen Air's most senior Pilots he's logged thousands of hours in this type of plane 301 ready for takeoff Runway zeroing here for takeoff Runway zero eight three zero one thank you a good plan good flight good fight is on this flight as a relief pilot like first officer gergen he's been flying the 757 for less than three months [Music] as the plane accelerates to take off speed a light rain begins to fall power set check first officer akut gergen watches his airspeed indicator for a routine instrument check as the airplane's accelerating to takeoff speed the first officer calls 80 knots 80 knots the captain in theory should verify that his airspeed indicator also reads 80 knots indicator's not working the captain's AirSpeed should read the same as his first officers 120 but the readings do not match is yours working yes sir you tell me Adam wants his first officer to tell him when the plane hits takeoff speed V1 at 150 knots the plane hits V1 the point of no return rotate the captain must pull back on his column and get the plane in the air positive climb Gear Up positive decline here is [Music] at 11 42 the plane takes off seconds later Captain air Dam's airspeed indicator comes to life is off climb fast time thrust first officer gergen reduce his power to the engines for a gradual climb to cruising altitude 301 Airborne four five switch over Santo Domingo one two four three one two four three bye-bye sir climbing through 2500 feet first officer gergen establishes contact with the Island's main tower in Santo Domingo alfalima whiskey 301 claim and maintain 280. Central piloton please Center autopilot as command one minute and 30 seconds into the flight the autopilot takes over foreign [Music] computers now make all the calculations and adjustments necessary to keep the plane climbing safely almost immediately the computer reports a problem rather ratio mock AirSpeed trim two different alerts warn the pilots that the plane is traveling far too fast but the first officer's airspeed indicator shows the plane climbing at a normal speed 220 knots something's wrong here unaware that there are any problems the controller directs Bergen Air flight 301 to continue climbing I'll find my whiskey 301 report okay two eight zero I'll call you over 4K 301.

okay there's something crazy do you see it in the cockpit the situation gets more confusing the first officer's airspeed indicator shows that the plane is flying much too slowly [Music] foreign mine shows only 200 now and decreasing sir but the captain's gauge shows the plane flying far too fast 325 knots both of them are wrong what can we do let's check the circuit breakers yes sir [Music] as the first warning is eliminated a more persistent warning replaces it the overspeed warning tells the crew that they are approaching 350 knots the maximum speed at which the plane was designed to fly at this altitude okay it's not matter let's pull the airspeed let's see resetting the circuit breakers turns off the alarm but it doesn't fix the problem Captain edem's airspeed indicator still shows he's flying much too fast now it's 350 yes confused by the conflicting information Captain edem decides to do what the plane wants he slows down with terrifying results 757 is sending out warnings that are confusing the crew bewildered the crew struggles to solve the problem s of 189 people depend on them getting the answer right shortly after taking off from the Dominican Republic Bergen Air flight 301 is in trouble the cockpit is filled with an ominous sound the stick Shaker alert the stick Shaker warning is a warning of imminent stall it means that the airplane is about to attain a speed so low that it cannot sustain flight the alert is so serious that it actually shakes the Pilot's control columns combined with a loud rattling it's impossible to ignore to add to the crew's confusion the plane begins to vibrate and dip wildly I'm sure every passenger on the airplane knew something was unusual because the aircraft started to uh started to Shake in a very violent maneuver it's not the only problem the crew is facing the attitude deviation indicator is basically a round gauge that on this airplane is a screen but it's blue on the top and brown on the bottom and it shows not only the pitch of the airplane but also roll on the gauge blue represents Sky the more blue the steeper The Climb showing that the plane's nose is pointing dangerously High then more than seven thousand feet above the ocean the plane rolls hard to the right begins to plummet from the sky from the time that the stick Shaker activates it is now going to require proper action from the flight crew to sort this out or they will end up losing control of it the window of decisions is closing on them for if they let it stall completely maintaining control of the airplane will prove to be very difficult Captain edem struggles desperately to get his plane to climb nose down has just a few thousand feet to pull a 100-ton airliner out of a deadly stall the less experienced Pilots utter prayers and offer suggestions 377 standby air traffic control is still unaware that flight 301 is in grave Danger climbing what am I to do how far altitude's okay the plane is falling fast five thousand feet Captain edem is trying to fly a plane that's become virtually uncontrollable pushes the throttles to full power but it doesn't help the plane spirals towards the sea oh what's happening Alfa Lima whiskey 301 Santo Domingo come in please alpha lima whiskey 301 Santo Domingo come in please less than five minutes after takeoff Bergen Air flight 301 vanishes from radar come in please the Dominican Navy begins searching for the missing plane and its passengers I was always thinking of what I would find I thought I would find people screaming people yelling asking for help they discover something very different the strong smell of jet fuel hangs over the water pieces of wreckage float on the waves to myself there was no one alive here we didn't see any survivors and we didn't see bodies I really thought the plane had disintegrated on impact within hours more than just wreckage begins floating to the surface around 5 20 in the morning when the body started to come up I did feel a great sorrow in my heart I felt like I wasn't sure if I would have the strength to continue the work at that moment the search continues By the Light of the next morning American and Dominican rescue ships scour a 1300 square kilometer area for survivors none are found now it's up to the Dominican Republic's aircraft accident investigation Bureau to find out what caused this accident we established a base camp at a hotel on the cabareta beach which is directly south of the accident site over the next couple of days investigators reporters and some of the victims families arrive at the hotel foreign evidence of the disaster reaches the Dominican Shores wreckage and passengers possessions are washing up on the beach even the smallest piece could be a valuable clue as to what caused the crash sa's National Transportation safety board agrees to assist the Dominicans with their investigation Dominican Republic they sent an investigator to Puerto Plata we could see that this was going to take some International cooperation to get to the bottom of the event Robert McIntosh will also provide support from the ntsb's Washington offices um any signal from the recorders this particular accident was the first major loss of a Boeing 757 in the water there was added urgency because the aircraft was going into the Livery of many American operated Airlines and on the market for the worldwide passenger service but uh in order to understand what had happened here we only had one key that key was the black boxes like all commercial airliners the Boeing 757 carries a cockpit voice recorder that records all the sounds in the cockpit and a flight data recorder that records a wealth of information about the plane's operation during flight we've got underwater locator beacons on these recorders they work for 30 days upon immersion but the ocean weather plane crashed is over 7 200 feet deep we needed to locate them before the signals faded and we also needed to remove them before the data was damaged by salt water so we were in a Race Against Time the NTSB enlists the help of the U. S Navy who hire a submersible called The Curve curve stands for the cabled underwater recovery vehicle it's it's a tethered vehicle it has an umbilical and it's controlled by an umbilical it's not autonomous the curve is essentially a remote controlled submarine which can work at depths no man's submarine could handle while the curve travels from the United States major Sioux France starts to examine the evidence he has radar on the ground tracked the plane as it climbed into the night sky the history of the flight is recorded here so basically investigators study the radar records along with the conversation between the ground controllers and the crew I have the recording from the control tower Santo Domingo good evening how to leave my whiskey 301 cutting report the exchange between the controller and flight 301 is normal the investigators detect no signs of trouble last communication between them was only disrupted with a standby three zero one Squad three seven seven stand by as you heard there's no reason why this plane went down what had caused something to go wrong to interrupt the flight path of the aircraft so rapidly certainly it was a good uh it was a good question for us any debris that's found is taken to a Dominican military base to be examined foreign through the wreckage they've recovered pieces of the cabin life vests even part of the landing gear have all been found every piece of debris is studied for signs of an explosion or fire [Music] investigators also check if any of the life vests are inflated that would suggest passengers had some warning before the plane plowed into the sea cords on some of the life vests are hanging loose but investigators conclude that could be the result of the plane's violent impact the crash was so powerful it has compressed coffee cans into flat pieces of tin the wreckage tells investigators that the crash of Bergen Air flight 301 was sudden and violent but they find no evidence that there was an explosion on board foreign looks into the possibility that the plane which was called into service at the last minute may not have been ready for the flight and also fraud ah hi I like to see some records of the regular plane they're right here it had been on the ground for some time in Puerto Plata and that became interesting to us why would uh why would an operating company have an aircraft sitting there investigators discover that the plane wasn't on the ground for repairs based on maintenance records the plane appears to have been mechanically sound Bergen air simply didn't have enough passengers to justify the flight financially so they kept the plane and the crew in the Dominican Republic for almost three weeks the plane's maintenance records turn out to be one more in a series of empty leads [Music] the curve arrives in Puerto Plata Harbor on February the 28th more than three weeks after the crash it slips below the waves looking for the remains of the burgundaire jet it takes the robotic submarine two hours just to descend the 7200 feet to the ocean floor from there it sends back images of the wreck of flight 301. the cockpit pretty much was sitting upright and it was pretty much the nose of the plane you know arm and you could see the front part of it it was obviously banged up and cracked and fragmented the clues investigators need to solve the mystery of this plane crash lie somewhere amongst the plane's Twisted wreckage the flight's black boxes are the top priority the curve quickly picks up the signal from a pinger on one of the units operators must now maneuver the sub towards the sound they have to be able to see the boxes to pick them up with the robotic arm foreign it takes just 90 minutes to find the first black box [Music] was sitting out in the open okay it was where they could see it and and they picked the first box up they grabbed a hold of it and they just kind of tucked the arm up in place you know so that they wouldn't lose it and black box is also heard but after almost two hours the curves cameras still can't see it you know they knew it was right there and they were searching around a debris pile and they could not physically see it you know with the cameras of the vehicle so as they went around a couple times they started you know lifting metal up and moving pieces out of the way and then they did find the second box under some debris [Music] foreign flight 301's flight data recorder and cockpit voice recorder are brought to the surface and loaded onto a waiting jet within hours the black boxes are at the NTSB labs in Washington DC technicians prepare to extract the precious data from the boxes investigators hope it will tell them what happened aboard Bergen Air flight 301 they'll soon uncover a stunning miscommunication between a seasoned pilot and his plane to unravel the mystery of Bergen Air flight 301 investigators are counting on the plane's black boxes flight data recorder was was our key so the technicians got busy and gave us plots visual plots of what was going on with engines and air speeds and so on to allow us to try and understand why that aircraft slowed down and then simply departed controlled flight and entered the ocean ah that shows us all we need to see from so it's all the flight data recording it's on a timeline top is the pitch we've got the airspeed and the altitude but check out the timeline 44.

investigators immediately noticed something unusual about the flight 15 degrees pitch nose up seems high it's almost the maximum and then it stays that way the plane began climbing normally pilot on please but investigators noticed that shortly after the autopilot was switched on the plane's nose pitched upward they also see that the plane's AirSpeed seems much higher than it should be 350 knots it can't be right oh there's definitely something wonky about the airspeed numbers this brought us to the question of perhaps we should be looking over on the other side at the cockpit voice recorder and see what kind of information was coming from there investigators soon start filling in the missing pieces of the puzzle my airspeed indicator is not working they learned that Captain Adam noticed that his airspeed indicator wasn't working yes sir you tell me V1 rotate but Adam didn't think the problem was serious enough to abort his takeoff the tape reveals that once they were Airborne the crew quickly became overwhelmed by a series of warnings or something to investigators the captain seems to become increasingly bewildered by the messages he was getting from his plane mine shows only 200 now and decreasing sir both of them are wrong what can we do investigators don't know why the captain's airspeed indicator wasn't working they do notice that the captain's gauge came back to life as the plane started to climb okay it's no matter let's pull the airspeed let's see it's a telling discovery which leads investigators to focus their attention on the device that feeds the gauges AirSpeed information the Pito tube a pitot tube is an AirSpeed sensor a pipe open at one end that responds to air pressure when the plane travels forward an increase in air pressure inside the pitot tube causes the airspeed indicator's needle to move [Music] my airspeed indicator is not working but if a Pito tube becomes blocked it can send faulty readings to the plane's gauges blocked pitot tubes have been a factor in previous plane crashes in 1982 a Boeing 737 crashed in heavy snow in Washington DC shortly after takeoff the pitot tubes were blocked with ice [Music] investigators suspect that the pitotube which fed the captain's airspeed indicator on the Bergen air jet was somehow blocked but they know ice can't have blocked the tubes of a plane taking off from a Caribbean Island we don't know why it was blocked but it presented a very very interesting situation to us we started carefully looking at what could cause that kind of thing to happen foreign has a theory he returns to question the airplane's mechanics here's the front thank you I like to ask you some more questions about the Bergen airplane Sue Fran suspects the mechanics may have tapes over the Pito tubes during maintenance it's a common procedure but if the tape wasn't removed it could have caused the deadly accident was left on accidentally no sir they didn't have to be taped we never did anything with the petals did you put the pedal covers back on them when the maintenance was finished it didn't have any coverage with it we didn't take any off and we didn't put any on [Music] yeah and that's when we discovered that the pitos had not been covered for the 25 days that the aircraft remained parked at the international airport in Puerto Plata a Pito cover slips over the end of the tube regulations state that these covers must be installed any time a plane will be on the ground for an extended period of time a prominent flag is meant to remind pilots and technicians to remove them again before takeoff investigators find that the Bergen air Pito tubes were never covered and somehow the uncovered pitos had become blocked recovering the tube from the ocean floor is the only way for investigators to answer a pressing question what blocked the pitot tubes nobody knows for sure the evidence is seven thousand feet down in the Atlantic Ocean but even if the pitotubes were blocked how could it have caused the crash of a modern jet and the death of 189 people it's not like a car where you have only one speedometer in this kind of an aircraft you have a total of three AirSpeed indicators and there's a flight data computer which is Computing the Velocity in relation to the ground using information from the black boxes the NTSB pieces together a real-time animation from liftoff to the final moments of flight 301 this is the indicator would the captain actually realized that his speed indicator was not working is yours working yes sir the big question for investigators is how could one faulty AirSpeed Source result in a crash you realized at a time when he could have aborted could have turned back chose to continue investigators analyzed the captain's every move and find that he allowed a small error to escalate and ultimately overwhelm him rotate positive claim Gear Up moments after liftoff Captain adem's airspeed indicator appears to be working but investigators suspect the gauge is responding to changes in altitude as the plane climbs through the thinning atmosphere the air trapped inside the tube expands causing a buildup of pressure inside the cockpit this causes the airspeed indicator needle to deflect even though altitude is causing the increase in pressure the sensors mistakenly read it as an increase in airspeed there's nothing Captain Adam may have had five separate sources of AirSpeed to rely on but investigators noticed that when the trouble started he wasn't flying the plane Center autopilot has command thank you the autopilot was and unless the crew reconfigures it the autopilot gets its AirSpeed information from only one source remember let's get stayed up on our own Captain's beetles the one that was blocked the data shows that the trouble on Bergen Air flight 301 began when the autopilot took over right after the autopilot is engaged the plane's nose begins to rise investigators suspect that the crew didn't realize that the blocked pitot tube was feeding the autopilot faulty information the computer registered that the plane was traveling too fast and raised the nose to slow it down raising the nose works like an air brake it slows the plane by creating drag the autopilot is programmed to never bring the nose higher than about 15 degrees any higher and the plane would slow down too much and stall the autopilot's a pretty smart guy he already knows she's got all the power that he's going to get for the climb the only thing for the autopilot to do is raise the nose and it raised the nose of the airplane to its limits of authority but the autopilot was reacting to faulty information moments later it sent out two different warnings rather racial that the plane was traveling too fast to be controlled safely and the airplane begins picking up warnings a Rudder ratio a variety of things that the airplane is sensing problems okay there's something crazy here do you see it yes there is something crazy mine shows only 200 now and decreasing sir both of them are wrong the investigators realized that Captain Adam wrongly concluded that both AirSpeed indicators were malfunctioning in fact his first officer's gauge was always correct the plane was traveling much too slowly what can we do Captain America no longer knows which instruments to trust let's check the circuit breakers as they saw these caution lights they decided they were going to start pulling some circuit breakers and that would be rather strange the actions of trying to reset circuit breakers is some things that Pilots of older Generations aircraft have learned via experience of sometimes being able to get an errant system back functional resetting the circuit breakers turns off the alarm but that needle continued to climb around the the clock face until it activated the overspeed warning the autopilot system sent yet another warning that the plane was traveling too fast but the reality was just the opposite the plane was slowing down at this point the over speed of the errors are good going slow they think they're going too fast and confusion is set in let's pull the airspeed that's when Captain edem made the greatest era of all you can see that he now pulls back investigators realize that at the plane's already slow speed pulling back on the throttles was disastrous the crew got the most severe warning that a plane can send out distinction he's got a tactile sense coming through his flight controls that literally shakes the stick and says you've got to lower this note in a matter of seconds Captain Adam was first warned that his plane was traveling too fast and then that it was traveling dangerously slowly they're in direct opposition of each other and two warnings that you would never expect to get one right behind the other autopilot is programmed to always disconnect when the stick Shaker activates it's up to the pilot to get the plane out of a stall watch the autopilot reached its limits of authority it said I've done all I can do I'm out of here when the autopilot disengaged Captain edem suddenly found himself in control of the plane at the moment of his greatest confusion if you watch the plane at the top of the screen the cockpit recordings lead investigators to a stunning conclusion Avi Captain Adair may not have recognized that his plane is about to stall but the relief pilot behind him did ADI this additional pilot intervened to say ADI ADI in other words look at that ADI and put yourself where you would normally see the nose of the aircraft five degrees nose High 10 degrees so when the reserve pilot says ADI he is attempting to focus the captain's attention to role in Pitch which are becoming problematic the relief pilot wanted Captain Adam to recognize that the plane's nose was pitched dangerously Skyward investigators can hear first officer gagan trying to convey the same message nose down at this point the first officer is actually tried to lead the captain to some solutions but not actually take control of the airplane what the 757 desperately needed was airflow over the wings to generate lift the only way to get that was to point the nose down and dive what puzzles investigators is that the first officer had a control column identical to the captains he could have pushed it and brought the nose down himself he may have been able to save the plane [Applause] he didn't instead he and the other Turkish crew member continued offering suggestions to their more experienced but overwhelmed Captain but climbing what am I to do you can live a life our altitude's okay the recording shows that Captain air dam ignored valuable advice that could have saved the plane and in the burgundy case there's a case of a relatively Junior FIRST officer looking at one of the most senior captains on the airline it is not culturally appropriate for him to say I'm going to take the airplane away from you instead he tries to assist the captain to lead the captain but leave the captain in command other cultures other training other airlines may very well have required the first officer to physically take control of the airplane I think the the social uh atmosphere in the cockpit will prevail to Revere age and experience to the point where it it can kill somebody and in this case it looks like it did the flight data recorder reveals that instead of pushing the nose down Captain Adam tried to get more speed from his engines at this but this will goes to full power at the angle the plane was falling the engines couldn't get enough air applying full power was more than they could handle the left engine quit first with the right side at Full Throttle The Airliner swings around as though its left wing were caught on a branch the airplane goes into a classic full stall where the nose drops it falls on a wing which is now a very life-threatening condition the 757 itself makes the situation worse like many modern jets it uses a so-called swept Wing design the wings angle slightly backwards to reduce drag and increase fuel efficiency but the design has a downside one of the characteristics of swept Wing Jets is they get less and less stable they're much harder to fly as they approach stall [Music] to maintain control of a swept Wing Jet with no more altitude than they had in this condition is very very problematic and they are not successful and the airplane goes into the water investigators now know why Bergen Air flight 301 crashed what they can't understand is why the flight ever left the ground 80 knots my airspeed indicator is not working at 80 knots if the pilot and co-pilot's instruments disagree takeoff should be aborted [Music] investigators are troubled that the captain took off knowing he had malfunctioning instruments if something is not functioning correctly it doesn't matter what it is one should abort the takeoff at 80 knots this decision on the part of the captain has been criticized but there is a very short time window for this decision to be made members of the investigative team in Puerto Plata try to find any clues that might explain why Captain edem didn't abort his takeoff it was raining that night perhaps he was worried that he wouldn't be able to stop his speeding plane in time procedurally he's required to stop but high-speed aborted takeoffs are something that are very serious and that flight Crews trained to avoid high-speed aborted takeoffs if possible and we certainly looked at the parameters of the runway to ensure that there was adequate runway in the in that particular situation careful measurements are taken investigators conclude that at 80 knots when he first noticed the problem Captain erdem had enough Runway left to bring his plane to a stop he could have aborted his takeoff there's also the question of the hastily assembled crew investigators now wonder if the last minute nature of the crew's call could have influenced their decision to take off Bergen air started with a a crew that probably didn't expect to fly that night they didn't have adequate rest they got out to the aircraft and perhaps were rushed in some of their planning investigators consider the possibility that the crew who had been away from home for more than two weeks was simply too eager to get home zero eight three zero one thank you a good flight good flight good fight this is the homesick Factor where minor problems are ignored in order to get back home investigators will never know what was going through Captain Adam's mind when he opted to continue his takeoff in this case the airplane is accelerating rapidly enough the first officer responds B1 which is the commit to fly speed and by training now the decision window has closed they need to fly rotate and immediately thereafter in their Airport once the plane was in the air it's blocked pitot tubes caused Captain air Dem to make a series of critical mistakes but how were the tubes blocked in the first place investigators will find that the deaths of 189 people was caused by something the size of a paperclip [Music] investigators now know that a blocked pitot tube led to a series of conflicting warnings that confounded flight 301's captain now they want to know how those same warnings would affect other Pilots [Music] we went to a flight simulator and in the simulator we tried to recreate the conditions of what happened on the night of February 6 1996.