How a terrible coincidence brought down this Aircraft | Tarom flight 371 - YouTube

Channel: Mentour Pilot

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it's the 31st of march 1995 and an
airbus a310 from taron airlines is
flying its standard instrument departure
from the 08 right in bucharest
initially everything looks okay but
about a minute and a half into the
flight it's obvious that something is
right the aircraft starts banking more
and more towards the left
the nose starts dropping and they find
themselves in an almost vertical nose
dive down towards the ground
seconds later the worst aviation
accident in romanian history is a fact
how come that a pretty minor technical
malfunction have led up to this and what
has happened to the pilots
well in order to understand this we once
again have to turn our attention towards
the final report
so stay tuned
the aircraft involved in this incident
was an eight-year-old airbus a310
initially it had been bought by
pan-american airlines and when they went
delta airlines had taken it over and
then about a year prior to the accident
the taram airlines had bought the
this aircraft did have some technical
issues specifically
with its outer truss systems the atf
what had a tendency to happen was that
as the aircraft was transitioning
from its takeoff phase into its climb
well then the trust should be reduced
back to what we call
climb thrusts but on this particular
when that happened several times instead
of just
setting the trust the number one trust
lover the one that's controlling the
left-hand engine had started reducing
back towards
idol while the number two engine would
have stayed at the take-off thrusts
now airbus was aware that there was some
issues with the autotron systems on the
early airbus a310s
and they have found out that it probably
had to do with some
excessive friction between the linkages
of the
couplings that you can engage with the
truss levers and the truss levels
and because there was only one motor
driving the truss levers
if one of the truss levers got stuck
well then
the mechanism would feel that actually
you know the trust that we have asked it
to set is not set
and it will continue to drive so the
trust level that did not
have an issue would drive backwards all
the way to idle
while the truss lever that got stuck
would just sit where it was sitting
this particular failure had occurred
both when the aircraft was owned by
delta airlines and also at least
12 times when tarum had taken it over
but the issue here was that any time
that the pilots would report this the
aircraft would come down on the ground
maintenance would take over and they
would start to try to replicate the
failure to see where it was
but they were unable to replicate the
failure instead they would follow the
that airbus had sent out something
called service information letters which
basically um a step below a service
okay a service information ledger is
something that the manufacturer would
send out
when they are aware of what they think
of causing this
but they haven't found a permanent
solution to it and in this case
it was replacing the bearings but
replacing some of the linkages
and also just kind of lubricating the
whole system
and anytime that maintenance did this it
would solve the problem
right they wouldn't be able to replicate
it and it would take several months
before the same problem would come back
because of this therm airlines had
actually issued something called the
briefing card to its crews
and that's a permanent entry into the
tech log where
all of the crews that are flying the
aircraft when they're looking through
the technical status of the aircraft
they will see that okay there's a
briefing card and they will see that
time and time again this spurious
failure would come in so make sure that
you're guarding the trust levels during
departure phase um in case you'd come
back and then obviously put it into the
tech log
and the last entry into the tech log
that was referring to this particular
was about 15 days earlier on the 16th of
however subsequent investigations would
that this failure had actually happened
on the flight
preceding the accident flight as well
when the aircraft was flying from dubai
to bucharest
but the crew had not entered it into the
the reason behind that we will never
really know but it is possible that the
previous crew
knowing that this was actually stated in
the briefing card
didn't think it was important enough to
put it into the tech log again
in the flight deck of terrorism flight
371 was captain
livio bartanio he is 48 years old
had 14 312 hours of which
1735 was on the airbus a310
his previous experience prior to that
was mainly on the back 111
and on the boeing 707. together with him
in the cockpit was first officer ian l
stoy he had 8988 hours of which 650 was
on the airbus a310
and his previous experience prior to
that was mainly on soviet-based aircraft
like the illusion 1
8 and the illusion 62. there was also
nine cabin crew members and 49
passengers onboard this flight
terror flight 371 was scheduled to fly
from bucharest international airport
over towards
brussels international airport the
weather on the day of the departure was
not great it was
cloudy with some low hanging clouds and
also some snow showers in the area and
because of the snow showers the crew
decided that they needed to de-ice the
aircraft prior to departure
they loaded the aircraft up with about
20 tons of fuel to bring them towards
and because of the icing they got a
little bit delayed
when they were preparing for the um taxi
now during the pre-flight inspection and
during the pre-flight briefing
there was discussions regarding the
briefing card so the crew clearly knew
that this aircraft had had issues with
its ats system before
because of this the captain decided that
the first officer was going to be the
pilot flying for the leg and
he the captain was going to be guarding
the trust levels not only during
the takeoff which is what we always do
but also during the climb about to make
that the trust lovers wouldn't start
going back and starting to get this
trust level disagreement at times 05 54
the crew was ready for departure and
they called up the tower
to ask for pushback and startup
clearance soon after that they started
taxiing out for departure runway 08
right in bucharest during the taxi out
once again
the captain restated who was going to do
what during the departure
that it was going to be a standard
briefing for a right
seat departure on the 08 right and when
they had received their departure
they were expecting to climb straight
ahead for a couple of nautical miles
and then turn left towards a vor a pro
trade called
sierra tango juliet and this left-hand
turn is actually going to play a major
part in what's about to happen
at times zero six zero six and 44
seconds utc
the uh aircraft starts rolling down the
runway and everything looks completely
normal during the takeoff roll
the only thing that's noted on the
cockpit voice recorder is the captain
telling first officer to remove his
hands from the trust levels
and put both of them on the control
um this this is considered quite normal
normally during the takeoff role the
captain is the one that's guarding the
trust levels in case a rejected takeoff
will be needed
the aircraft rotates normally gets
captain calls out positive rates to
which the first officer responds with
asking to get the gear up
the captain retracts the gear and also
does a couple of associated
extra things like turning off the
landing lights and disarming the
aerodynamic brakes the aircraft
continues to climb
normally and at the time zero six zero
seven twenty so that's about 30
seconds after departure the captain
contacts the departure controller
the virtual controller comes in and
tells the aircraft that they can turn
left early towards sierra tango juliet
now remember that they were expecting to
fly straight ahead so the fact that
they're now getting a clearance to turn
to the left early means that they have
to go into the flight management
and tell the aircraft that they have to
make a turn
so the first officer asks the captain to
do this this is also standard procedure
pilot flying concentrates on flying and
any updates to the navigation
is done by the pilot monitoring but
as the captain is now reaching down to
the flight management computer to update
the new clearance
they reach about 2000 feet which is
about 1500 feet above
ground level i remember this is
where the outer truss system now couples
with the truss levels again to drive it
from take of trust
back towards climb trust so as the
captain is
working on the computer here
the trust levels start to move and the
reappears so the number one trust lever
which is connected to
the left hand engine is now starting
to reduce backwards towards idle
slowly with about one degree of trust
level movement
per second number two anden is stuck
in take off trust but because the the
has left the trust levels and is now
focusing on
the fmc it's likely that he does not
notice that this is starting to happen
and also on top of this remember that
they're expecting to make a left-hand
well if this would happen
if you start to get asymmetric trust so
that the trust is reducing on your left
hand side but staying the same on the
if you're staying on a straight ahead
track you would notice this because the
aircraft would want to
yaw towards the engine with less thrust
but because this aircraft is now
initiating a left-hand turn
this is now likely masking the fact that
they're starting to get
asymmetric trust and because this is not
an engine failure or a failure of any
sort that is connected to any kind of
there is no indication to the crew other
than the position
of the truss levers that this is
happening the aircraft continues to
first officer is in a initially quite
left banked turn with about 15 to 20
degrees of bang
but the bank angle is steadily
increasing and this
might be because of the asymmetric trust
that they're now facing
but none of the pilots are noticing this
and as they climb through about 3 000
the captain looks up at the primary
flight display and notices that the
speed is not accelerating as it should
then he calls out speed
first officer acknowledges that pitches
down a little bit in order
for the speed to continue to accelerate
and soon after that
at about 3 300 feet or so the first
officer says
250 knots inside flaps up
captain responds and selects the flaps
but here something else is going wrong
because as the aircraft continues to
climb now
the first officer asks for the slats to
be retracted which is a
separate thing to do on the airbus 310
but he doesn't get a response back from
the captain
so he calls it out again nothing happens
instead on the cockpit voice reporter
you could hear
something that can be interpreted as the
sound of human pain as
in someone groaning on the flight deck
first officer is asking what's what's
the matter with you what's up with you
but it doesn't get any reply so
the aircraft is now in a left-hand turn
the trust's asymmetry is starting to
increase more and more and at this point
it's at about 0.19 epr
the first officer would be very
concerned at this point remember they've
just taken off and there's obviously
wrong with his colleague so the
workload that the first officer is
feeling is going to start to
increase very rapidly here and you have
two things
that is happening at the same time both
the incapacitation of
his colleague potentially and also this
kind of subtle malfunction that's
happening in the background
the problem is though that this subtle
malfunction to the ats
system is going to have very real
on the flight controls of the aircraft
the bigger the asymmetric
trust becomes the more of a yaw is being
introduced and as this aircraft is
already in a turn
the bank angle just continues to
increase the bank angle of the aircraft
is now approaching 30 degrees which is
normal maximum when we are in normal
operations of the aircraft
the trust's symmetry is at about
0.36 epr still increasing
the aircraft is still climbing but the
first officer is now becoming more and
more concerned with his colleagues there
are indications that he tried to make a
radio call at this point but there's
nothing indicated on the cockpit
voice recorder instead the aircraft just
continues to increase
its bank angle now for any one of you
who knows a little bit about
flying aircraft or maybe i've seen my
videos about how to make steep turns
you know that the more the aircraft is
the more back pressure you need in order
to keep
the noise above the horizon if the bank
angle continues to increase and you
don't do anything about it
the nose is going to start to decrease
and drop
further and further down and the
aircraft is going to start descending
and this is what's starting to happen
now as the aircraft continues to climb
it reaches a maximum
altitude of 4620 feet
the bank angle is down about 43 degrees
and as the bank angle continues to
increase now the nose of the aircraft is
going to drop below the horizon and
a rapid descent follows
at about this time there is an
indication that the first officer is
for the autopilot to be engaged and he
actually reaches
up and engages the autopilot as well
but because he is still inputting back
pressure on the control column
the autopilot only engages for about one
second before it disengages again
and when an autopilot disengages it will
with an alarm to you know basically tell
the pilots that
the autopilot hasn't engaged properly
this is called the cavalry alarm on the
on the airbus and it's a very loud alarm
this alarm goes off and it keeps
sounding for the remainder of this
as the aircraft is now descending down
through 3600 feet
there is a call on the cockpit voice
recorder where the first officer says
this one has failed which indicates that
he is now trying to
understand what is going on with this
but you have to understand that at this
when the first officer likely is looking
up and on to his instruments he's
finding himself
in a really really critical attitude the
nose has dropped
well below the horizon in fact at the
point here it's pointing downward with
as much as 83 degrees which is basically
straight down towards the ground the
role is continuing and in fact the
aircraft rolls completely around
its roll axis and as the aircraft is now
heading straight down towards the ground
the speed is increasing very very
here there's also an indication that the
trust levers are starting to be reduced
and the reason for that
is likely that the aircraft is
overspeeding and there is a protection
in the ats in the autotrust system that
feels if the speed is getting too high
it will start moving the truss levers
back again and
it's very possible that whatever was
holding the number two truss level up
before has now given way and the trust
is starting to decrease
this however has no real implication to
what's about to happen to this aircraft
what is a little bit interesting is that
there was no overspeed
warning the reason for that during the
subsequent investigation
was thought to be that the cavalry
the autopilot disconnect alarm is
actually set as a higher priority than
the overspeed alarm
so that if the autopilot disconnect
alarm was going
then the overspeed alarm would not be
similarly it's also interesting to
understand why
they didn't get any gpws warning ground
proximate warning system which was
included in this aircraft the
the thought behind that was that because
the gpws is using the radio altimeter
which is situated at the belly of the
to measure closure rate towards the
ground if the aircraft was actually
rolled over almost completely well then
there would be no
readings from the radio altimeter either
as they were now hurling towards the
the highest speed recorded before the
aircraft impacted with the ground was
324 knots and a negative attitude of
50 degrees so when the aircraft impacted
the ground
less than two minutes after departure it
did so with an absolutely horrendous
force it was a completely non-survivable
event and all 49 passengers and 11 crew
perished immediately
the crash site was only a couple of
kilometers away from bucharest airport
and fortunately it happened outside of
any populated area
the aircraft investigators came to the
scene and started to
to try to get a picture of what had
happened and because
of the very high angle that the aircraft
impacted the ground with
and the actual crash site was relatively
small but part of the aircraft was found
as deep into the ground
as five meters it was not possible to
make any post
mortem on the first officer and the
captain because of the
severity of the damages so we will never
really know
what happened to the captain or to what
extent that
he was incapacitated but what we do know
from both the cockpit voice recorder and
from the flight data recorder which was
recovered from the crash site
is that after that initial groan that
was hard on the cbr
there was no more input neither voice or
inputs on the controls
from the captain so it's likely that the
first officer was completely by himself
during this event
so now the issue for the investigation
is to try to figure out why this
happened in the first place
they very quickly honed in on the issues
that have been previously recorded on
this aircraft with the auto trust system
and they understood
that it's likely that this was a piece
of the apostle but what they couldn't
was why this would have caused this
crash in the first place
and it was only when they looked into
the cvr and they realized the
of when this issue
started appearing at around 2000 feet
the captain
was heads in onto the computer
trying to update the fmc and then the
subsequent incapacitation
by the captain first officer being
potentially preoccupied with what was
happening to his colleague
as this was happening at the same time
and this could potentially explain why
the deteriorating attitude of the
aircraft went undetected for so long
but it doesn't explain why the first
officer was unable to rectify the
once he realized how bad it was but
we're gonna get to that in a few minutes
guys i hope that you are finding this
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short minute after this message
i'll tell you how the training of
commercial pilots have changed after
this accident so stay tuned
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the final report came to the conclusion
that the following casual factors was
the reason for the crash
number one there was trust asymmetry
number two a incapacitation of one of
the pilots in this case
the captain and number three the
insufficient corrective actions
from the co-pilot in order to rectify
the situation that came
from the first two points
there were two safety recommendations
that came out of the final report both
of them were aimed at
airbus industries the first one
basically said that there needed to be
some kind of service bulletin or air
boardness directive issued in order to
make sure that the underlying reasons
for the trust asymmetry was dealt with
airbus fairly promptly issued two
service bulletins to deal with this on
all of the aircraft affected
by this potential increase in
friction between the couplings and the
trust levels
the second one had to do with language
used in the
maintenance manual for example but
none of these recommendations talked
about the pilot
and why the pilot would have lost
control in the first place
and this is something that really stuck
with me um
i i didn't feel that the final report
gave me
sufficient closure on this one because
from all i could read when it came to
the experience of the first officer and
his training records and everything is
that this was a very good
pilot right he had really good training
history he had he was liked by his
everything pointed towards a really
experienced high-functioning
pilot and the only thing really wrong
except for the fact that the captain was
was some trusty symmetry and actually
when he found himself
in that attitude the trusty symmetry
likely wasn't even there because the
trust lever on engine number two
had already come back so why was it that
he wasn't able to recover the aircraft
so i brought this to detention of my
patreon crew i love going to my patreon
crew and kind of talk to them about
things like this
and one of my patreons who called
brought my attention to a specific part
of the first officer's
experience and what he brought to my
attention was
the type of experience that the first
officer had
the first officer had close to 9 000
hours in total
but out of those 9 000 hours only 650
was flown
on western built aircraft the rest over
8 000 hours
was actually on illusion 1 8 and
illusion 62.
now there is a crucial difference
between western
and soviet-built aircraft when it comes
to one of the most important
instruments in the cockpit which is the
artificial horizon that's the instrument
that shows how the aircraft is actually
in relation to the horizon because as
we're flying inside of a cloud
we cannot feel what is up and down okay
it's impossible
g-forces makes it impossible for our
inner ear to understand that
we have to have something to look at
that tells us an accurate picture
of what's going on and the primary
instrument for that is the artificial
on western-built aircraft the horizon is
there is an aircraft symbol and then the
artificial horizon is moving depending
on the attitude of the aircraft
now on soviet-built aircraft the horizon
stays fixed in the gyro and it's the
aircraft symbol that is moving instead
so if you look at the attitude in a
western built aircraft but your mental
is the russian built aircraft well then
if you straighten out the horizon
it will actually look like the aircraft
is turning the opposite way
if you as a pilot find yourself in a
really high stress
situation like the first officer in this
case definitely found himself in
you look up and your attitude is
severely out of what you would consider
to be normal
well then the way that your brain
interprets the information in front of
you is going to be
crucial for your actions following that
and if you for just a split second
misinterpret what you're seeing in front
of you
and put the wrong inputs into the
controls or too little
inputs into the controls or even no
inputs as in you're struggling
to to understand what it is that you're
seeing in front of you
this might be fatal especially at a low
altitude like this
but if this actually did play a part it
wouldn't have been the first time
in fact another crash crosshair flight
49er 8 was
also partially blamed to the pilots
their artificial horizon
this accident was like every other
aviation accident a huge
tragedy but like we've learned
throughout this series of air crash
we as an industry always try to learn
from anything like this and to make sure
that the industry as a whole becomes
better and safer afterwards
and this is also true with rom flight
371 after this accident and other
incident that involved palliative
the way that we train commercial pilots
to deal with pallet incapacitation
was upgraded so right now if you are
going for
your initial type rating on any
commercial aircraft you are going to be
practicing this
in different phases of light and the
and the priority whenever you find out
pilot incapacitation
is for the remaining pilot to focus on
flying the aircraft
right make sure that the aircraft is
fully under control
get it up to a safe altitude get the
in and only after that then you can pay
some attention to your colleague
the first thing that you do is to verify
they haven't inadvertently touched any
switches or any gauges or done anything
to the flight deck so you verify that
the flight deck is completely safe
the automatics is in and then you call a
mayday to air traffic control
ask for as much help as you need from
them and you also contact the cabin crew
to come in and help you
to potentially administer cpr
or secure the pilots in its seat
so that's what i wanted to tell you with
this video guys as always i'd love to
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with more than 3500 people in there at
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and last weekend for example we
had a group flight where some guys got
together in the discord server they
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went island hopping in microsoft flight
sim 2020 discussing talking amongst each
other on the discord server
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download it today
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nice community we do aviation quizzes
most sundays we're discussing flight
training and we're swapping pictures
with each other anything really
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