(ALARMS BEEPING)
Wrong way! Other direction!
A late-night flight in Russia...
..ends in a harrowing crash.
The flying control surfaces,
the fuselage, the engines - totally destroyed.
Investigators search for a mechanical explanation for the crash.
The split in engine balance
makes it more difficult to fly, but it shouldn't cause a crash.
- But when they dig deeper... - It doesn't make sense.
- It's like all hell broke loose. - ..they make a shocking discovery.
- Just do it all yourself, OK? - Take it! Take it!
Why isn't the captain helping him?
821, is everything OK with the crew?
It's the middle of the night in Russia.
A passenger jet is 45 minutes from
touching down in Perm, a city in central Russia.
There are 82 passengers onboard.
Most of them are Russian.
43-year-old first officer Rustem Allaberdin
is the pilot flying tonight.
The captain, Rodion Medvedev, 34,
is monitoring the instruments and radio communications.
The two have only flown together twice before.
Did you see the latest schedule?
Not yet. How is it?
It's ridiculous. They think we're machines.
Aeroflot Nord is a regional airline
and a subsidiary of Russia's state-owned airline Aeroflot.
INTERPRETER: Regional airlines sprouted up between 1991 and 1995.
One of them was Aeroflot Nord.
The reputation of the company was fairly strong.
Flight 821 lifts off from Moscow just after 1:00 in the morning.
The plane is making a two-hour journey to Perm
and then returning to the Russian capital.
- Any new crew coming on in Perm? - I doubt it.
Great.
Captain Medvedev and first officer Allaberdin
are flying a 16-year-old American-built Boeing 737.
The twin-engine plane has clocked almost 45,000 flying hours.
Aeroflot Nord leased the plane in March 2008 to expand its fleet.
The demand within Russia was on the way up, so the industry needed
to get aircraft in, and the supply for aircraft obviously
was to come from the West.
Perm is a small international airport.
It has a single tower operating 24 hours a day
and one long runway running north-east to south-west.
The plan for Flight 821 is to approach from the west,
turn right and land on runway 21.
Good evening -
good morning.
This is your captain speaking.
We've begun our descent into Perm
and should have you on the ground in 20 minutes.
The local time is 4:50am, and the temperature is 7 degrees.
Flight 821, you're cleared to continue descent to 8,800 feet.
Follow Bravo approach pattern.
The Perm air traffic controller reroutes
Flight 821 to keep the runway clear for another plane's take-off.
What's this now?
- Why the change in direction? - I don't know.
Aeroflot 821, we are changing the approach due
to impending take-off of Lufthansa 319.
821, OK, understood.
He could have told us sooner.
Flight 821 must now wait for permission to land.
What's the weather like?
Light rain. Visibility 10km.
Aeroflot 821, turn right.
Descend to 6,800 feet.
Throughout the flight, the two engines have been
operating at different power levels.
That forces the first officer to make constant steering adjustments
to keep the plane on course.
How low must we descend?
The captain wants to know at what altitude they should begin their
final right turn to the runway.
821, descend to 2,000 feet.
Surface winds 050 degrees out, 10 knots.
Tailwind is 9 knots.
Increase your speed.
Right. Of course.
891 - 821, confirming base turn and descending to 2,000 feet.
The crew now prepares for landing.
Flaps 30.
Set.
The first officer notices the plane is veering left,
so he brings it back on course.
In the tower, the controller sees that Flight 821 is now
climbing instead of descending.
Aeroflot 821, according to my data you are climbing. Can you confirm?
Dammit!
The first officer adjusts the pitch of the plane to resume the descent.
We can confirm and we're descending now.
But now the controller sees Flight 821 has
flown past the approach path.
He instructs the crew to loop around and restart their landing.
Aeroflot Nord 821, restart your final approach.
Turn right heading 360.
Descend to 2,000 feet.
But the plane keeps going straight.
821, descend to 2,000 feet.
Turn right heading 360.
Follow my instructions strictly.
Flight 821 continues to ignore the instruction to turn right,
and then his radar shows the plane banking left and veering off course.
- Wrong way! Other direction! - In the cockpit, it's now chaos.
COMPUTER: Bank angle.
(SCREAMING)
- What's going on! - COMPUTER: Bank angle.
Bank angle.
Terrain.
Terrain. Pull up. Bank angle.
Bank angle. Bank angle.
The plane has crashed onto the Trans-Siberian railway
on the outskirts of Perm, Russia.
(SIREN BLARES)
It had nearly eight tonnes of fuel on board.
Local firefighters and rescue workers rush to the crash site.
Sunrise reveals the extent of the damage
to Aeroflot Nord Flight 821.
Nothing is left but charred wreckage.
All 88 people onboard die in the accident.
Their distraught relatives gather outside the Aeroflot Nord offices.
They hope an investigation into the cause of the tragic accident
will explain why their family and friends died.
Russian authorities labour around the clock to clear
the wreckage of Aeroflot Nord Flight 821 from the crash site
on the Trans-Siberian railway.
They need to get the trains running again.
Be careful with this. Bring it over here.
Meanwhile, Russian investigators
from the Interstate Aviation Committee,
the IAC, will work to find the cause of this tragic accident.
Photos of Flight 821's crash site offer up clues about the orientation
and pitch of the plane when it hit the ground.
The flying control surfaces, the fuselage, the engines -
totally destroyed.
And it flew past the approach line.
We need to find out why.
Russian investigators need to understand what could have provoked
a catastrophic loss of control just minutes before landing.
It was raining.
Let's track down the weather charts.
Thank you for making the trip from Washington.
- I hope we can help. - American investigators
from the National Transportation Safety Board join the team.
Bob Benzon is among them.
We were invited 'cause the Boeing was
manufactured in the United States.
The first priority is checking the weather
conditions at the time of the crash.
Visibility was 6.2 miles.
Some cloud cover.
Light rain. And hardly any wind.
Hardly challenging conditions for commercial pilots.
I agree.
One of the things we eliminated rather early in the investigation
was a problem with the weather.
What about the flight recorders?
On a plane to France. They're in rough shape.
The cockpit voice recorder and the flight data recorder
were so badly damaged in the fire
that they had to be sent to a specialised facility
in France to retrieve the data.
It could take weeks for results to return.
In the meantime, the Russian investigators brief the Americans
on their progress.
We found no evidence of mechanical failure in the engines.
What about an in-flight fire or breakup?
The plane first hit these trees on the left embankment,
and all the debris was confined in the immediate area.
There's no scorching on the trees.
No breakup prior to crash.
- The fire started on the ground. - Agreed.
After scouring through the wreckage and examining the impact details,
investigators are certain Flight 821 was intact before it crashed.
With no clues to work with,
the investigators wonder if Flight 821's air traffic controller...
Thank you for your time.
..can shed any light on the crash.
I keep playing it over and over in my mind.
- It doesn't make sense. - What happened when the plane
- made its approach? - Let me show you.
Here. The plane started climbing, but it should have been descending.
They were going to miss the approach lane,
so I told them to turn right and redo the approach.
Aeroflot Nord 821, restart your final approach.
Turn right heading 360, descend to 2,000 feet.
Aeroflot 821, can we continue our approach?
They wanted to keep the planned approach, but I said no.
821, understood and follow my instructions strictly.
And had to give the instructions
three times and still they didn't turn.
They seemed confused.
What he tells investigators next is revealing.
821, is everything OK with the crew?
Aeroflot 821, affirmative.
Once the captain confirmed everything was OK,
they still failed to turn.
- And then? - Aeroflot 821, please come in.
They confirmed the instructions?
Yes. Several times they said they knew where to go and what to do.
821, confirming descending to 2,000 feet and turning right.
Heading 360.
The controller deepens the mystery.
Why didn't the crew do what the controller asked?
What was really going on in the cockpit in the moments
before this horrible crash?
With the crash of Aeroflot Nord 821 still a mystery,
investigators need to find out if the 737 was mechanically sound
when it took off from Moscow.
When the Soviet Union split up, a lot of the resources
that the Russian aviation industry had were in short supply.
Spare parts were in short supply.
The skill of the engineers maintaining the aircraft
was reduced, and the aircraft were being operated on a shoestring.
In Russia, tracking down records
can be complicated by bureaucratic roadblocks.
Great. We got them.
Let's see what they can tell us.
Good. They go back to when the plane went into service.
But the team is lucky.
A safety and certification company, Bureau Veritas, regularly inspected
the Boeing 737 and kept detailed records going back years.
When this aircraft went down,
the rudder system became an object of interest.
Remember the design flaw
in the 737's rudder that we discovered in the 1990s?
It caused multiple accidents before it was caught.
In 1994,
USAir Flight 427 was approaching Pittsburgh...
when a rudder hard-over
caused the aircraft to nosedive and slam into nearby woods.
All 132 people on board that 737 were killed.
It was not an isolated incident.
A rudder hard-over was something that occurred because of a mismatch
between hydraulic pressure on the rudder on the 737,
which caused the rudder to move in one direction,
which could not be reversed with the rudder pedals.
Boeing decided to redesign
the actuator of the rudder system to prevent these rudder hard-overs.
Have a look.
Did they fix this one?
But you never can be perfectly sure that the fix is in.
The team now considers whether a frozen rudder caused Flight 821
to nosedive into the ground.
They hunt through the maintenance records
for any mention of the rudder.
Wait, I've got a work order here. It's from 2005 for
replacing the rudder PCU.
It's a match.
They took a look at the power control unit for the rudder
and found that the airplane had the new system fitted,
and then the investigation moved on from there.
With confirmation that the rudder's
- control unit was in fact replaced... - OK.
Let's see if we can find some airline maintenance logs.
..investigators now wonder if Aeroflot Nord, which leased the 737
only six months previously, kept up with its maintenance.
- Here. - Suddenly, a new clue appears.
A month before the crash,
the right engine started producing 20% more thrust than the left.
That's enough to throw the engine balance way off.
Investigators learn that during Flight 821,
the engines were producing asymmetrical thrust.
When one engine is producing more power than the other,
the airplane will rotate or yaw.
An aircraft flying out of balance
is sort of skidding sideways through the air.
To balance right engine with the left,
the thrust levers need to be staggered,
like this.
That's a big split.
It makes it very difficult to fly
the aircraft and manipulate the throttles when they're split.
Investigators discover that, just the day before the crash,
different pilots who flew the same
plane were so concerned about the problem, they took photographs
to show how far the thrust levers needed to be staggered.
It's a crucial lead.
A split in engine balance makes it more difficult to fly,
but it shouldn't cause a crash.
The auto-throttle can correct it most of the time.
But did these pilots know about the mismatch?
Take a look.
The crash day.
And it's signed by our captain.
Investigators now know there was a problem with the mismatched engines,
and they know the pilots were aware of it.
The question is, did they know how to fly the plane
with imbalanced engines?
The airline insists both pilots was very experienced.
Still looking for leads in the case of Flight 821,
the team shifts the focus to the pilots.
And yet the controller said the crew seemed
confused when he asked them to redo their approach.
Captain had over 3,900 flying hours, 1,400 of these at night.
That's not a tonne, but it's enough.
Wait. Two-thirds of his hours were in the cockpit of the Tupolev 134.
The Tu-134?
Built in Russia, the Tupolev 134
was one of the most widely used jets in the former Soviet bloc,
but it required twice as many crew members to fly them
as a modern Western jet like a Boeing or Airbus.
Russian aircraft were operated on a four-crew basis, and now you were
asking the pilots to operate solely on their own with no engineer,
no navigator, demanding more skill and knowledge from the two pilots.
The placement of the engines on the Tupolev is also different.
The engines are close together at the rear of the plane.
Mismatched engines require minimal
adjustment, since the thrust is all coming from the back.
When you add power, the airplane just accelerates ahead.
It doesn't pitch up. The nose doesn't come up.
Flying the 737, it's very different from flying the Tupolev.
A Boeing 737's engines are spaced apart, slung beneath the wings.
With a mismatch in engine power, the stronger side pushes the wing up
and requires the pilots' constant correction of control surfaces
to maintain balance.
The only way it can counteract an asymmetric thrust is to provide
bank, a small amount of bank
in the opposite direction to try and maintain the aircraft's track.
With this discovery, investigators now take a hard
look at how much the pilots knew about flying the 737.
The first officer had almost 9,000 flying hours.
While investigators discovered that the first officer
had 9, 000 flying hours, the captain had much less,
only 3,900 hours, less than 1,200 of which were on the 737.
That's low for a captain.
We need to find out if his training made up for it.
The captain had gone to Flight Training International
in Denver, Colorado.
Every pilot's training should be fully documented, but when Captain
Medvedev's training records arrive, investigators are shocked.
There's almost nothing here.
And all the paperwork surrounding that training had
pretty much disappeared.
It's a crucial development
that changes the course of the investigation.
Investigators delve into the training records
for the captain of Flight 821.
They need to know if he was properly trained to fly a 737,
especially one with mismatched engines.
The captain's English language skills were limited,
which begs the question, how much training did he understand?
All the technical manuals were written in English, and all their
operating procedures were written in English, the interaction with
the flight computers. So it really is quite a difficult task to
get that level of understanding in a very short period of time.
Medvedev got his training certification for the 737
on September 10, 2006, but then went back to flying the Tupolev.
He didn't get into the 737 again until...
January 9, 2007.
Investigators learn that Captain Medvedev
did not do a refresher course before returning to the 737.
He had a four-month break away from his knowledge,
and he had to have been forgetting things left and right.
Hardly a proficient 737 pilot.
Hardly.
Investigators now know that Captain Medvedev's training
on the Boeing 737 was woefully inadequate.
The team knows first officer Allaberdin had much more flying
experience than the captain.
OK, tomorrow we'll try in the air. Take care.
What they now need to find out is if the first officer
was any better equipped to fly the 737.
I am from IAC.
I have a quick question for you.
Investigators wonder how the first officer performed
during his 737 training.
He had plenty of experience on Antonov-2.
An Antonov 2 is a huge propeller biplane with a single engine
designed mainly for agricultural and forestry purposes.
The 737 simulator proved to be a real challenge for him.
Investigators learn that one thing the first officer
especially struggled with was flying with thrust asymmetry.
- Check the speed. You are banking. - COMPUTER: Bank angle. Bank angle.
- You're banking! - Bank angle. Bank angle.
This is the third time.
Bank angle.
The team now knows First Officer Allaberdin
needed much more training for flying with unbalanced engines.
INTERPRETER: The co-pilot, his situation is even more
dramatic than the captain's.
The instructor said that he cannot fly the asymmetrical thrust.
He wasn't ready even to be the co-pilot on this plane.
Investigators are astonished
by the extent of the first officer's shortcomings on the 737.
Medvedev was simply too green to captain the 737.
We can't tell how much of the English training he even retained.
The first officer had even more failings.
It was a mistake to put them together in the cockpit.
The team determined that the airline should never
have paired a new captain with such an unproven first officer.
But they still don't know if the crew's lack of training
and experience played any role in the crash.
Specialists in France have finally extracted the data
from the badly damaged flight recorder of Aeroflot Nord 821.
OK.
Now we can see what the plane was doing.
- Let's pull up the parameters. - Up to now, the investigators only
know what the controller told them about 821's path leading up
to the crash. The recorded flight data will tell them much more.
They focus in on the engine thrust parameters.
The first few hours of data provide few clues
as to the cause of the crash.
It looks like the auto throttle is on.
The auto throttle controls the engine's power setting
automatically instead of the pilot controlling it manually.
It's staggering the thrust levers and matching the engines.
OK.
Bring up the last three minutes of the flight.
Isolate this section.
It's like all hell broke loose.
The pitch and roll data paint a harrowing picture.
That's a barrel roll.
No-one stood a chance.
The investigation team continues to study the flight data to better
understand what happened onboard Aeroflot Nord Flight 821.
They have learned the first 1.5 hours of the flight was uneventful,
but when 821 starts the approach, things go terribly wrong.
OK, let's break this down.
The plane comes down to 6,800 feet.
Everything seems fine.
Until this.
The right engine is operating at 61%, but the left is near 40.
As the plane banks steeply to the right,
the auto throttle can't handle such a large split in engine power.
So it disengages.
Now, the first officer has to manage the massive stagger in the thrust
levers himself, the thing he couldn't do in training.
It required a lot more flying skill.
You had to compensate for the fact that the engine power
was mismatched, or you had to very
carefully move the throttles in a way that kept the power balanced.
And the crew wasn't very good at doing either one of those things.
What investigators discover next is even more puzzling.
The first officer now disengages the autopilot.
As the first officer begins the final right turn
towards the runway,
he performs a series of actions that disengage the autopilot.
He turns the yoke right, pushes it forward,
and engages the stabiliser trim in sequence.
Just like hitting the brakes when you're in cruise control.
This signals to the autopilot
that the pilot wants to take manual control, even if he doesn't.
In most instances, an autopilot is somewhat difficult to disengage.
But this man managed to do that by accidentally
trimming when he should not have.
The mismatched engines are now forcing the plane to bank
left and climb when it should be turning right and descending.
Take a look at this.
No-one has an input for 20, 25 seconds?
Investigators are astounded to discover that,
even though the autopilot is now off,
neither pilot makes any changes to throttle,
to pitch or roll for a full 25 seconds.
What is this?
No-one flying the plane?
If a pilot isn't aware that the autopilot is off,
then he can get himself into a lot of trouble
by not noticing airspeed changes,
by not noticing subtle turns,
by not keeping track of his altitude.
The team now knows more of the technical details
that contributed to Flight 821's crash,
but why things spiralled out of control in the cockpit
is still unknown.
Finally, investigators get the cockpit
voice recorder that captured the last 30 minutes of flight.
They hope it will provide the answers they need.
Are you guys ready?
OK. Let's hear now what's going on in that plane.
- Flaps 30. - Huh?
- Flaps 30. - Yeah.
Do what you have to do. Come on.
- Set. - Just do it all yourself, OK?
Hold it.
At 5:04am the first officer
has to call out the flaps twice before the captain even responds.
Why the captain commands his first officer to do it all himself?
It's essential that these two crew members work together.
The non-flying pilot would be operating the radio
but monitoring the progress of
the aircraft as well and monitoring the performance of the other pilot.
Investigators compare the flight data
with the cockpit voice recorder timeline.
Here it's clear there's a problem with the thrust.
With the auto throttle disengaged,
the mismatched engines cause the plane to veer left.
The first officer notices the aircraft banking.
He now makes the series of inputs that forces
the autopilot to disconnect.
This causes the aircraft
to climb and continue banking left instead of descending to the right.
821, is everything OK with the crew?
Aeroflot 821, affirmative.
Take it! Take it!
The first officer doesn't know why they're banking.
He wants the captain to take over.
Keep going.
Take it!
- Take it! - Take what?
- I can't do it either. - Oh.
Wrong way! Other direction!
- COMPUTER: Bank angle. Bank angle. - What's going on?
He needs to bank right,
but he's banking left instead.
He's confused.
The captain is looking at the 737's ADI but confuses
it with an Eastern-style ADI like on the Tupolev.
The ADI, or attitude director indicator, is the instrument
that displays an aircraft's orientation relative to the horizon.
In the Western ADI,
the airplane symbol remains fixed aligned with the actual airplane.
So as you bank the aircraft, the horizon will tilt
to show the same view as you would see if you looked out the window.
The ADI in older planes from Eastern bloc countries
worked just the opposite.
The horizon is fixed and the airplane symbol moves.
It's a huge difference.
The captain didn't know which way he was really banking.
Exactly. And he made the bad situation worse.
COMPUTER: Bank angle. Bank angle.
The captain was suddenly given control of the aircraft.
I think he looked down and didn't realise the situation
and started to bank it hard to the left.
The co-pilot said, "No, no, don't do that," but it was too far gone.
He may have reverted back to interpreting the instruments he
was used to when he was flying the Tupolev or the Antonov.
It was just a case of not being able to interpret the Western ADI.
But one last mystery remains.
Why was the captain so unwilling to take charge until the last second?
What was his problem?
The team investigating the crash
of Flight 821 has determined that pilot error
led to the tragic accident that killed 88 people.
The first officer couldn't handle the mismatched engines,
but the captain refused to take control of the situation.
Take it! Take it!
Take what? I can't do it either.
In order to better understand the psychological
state of the pilots,
investigators have analysed the pitch of their voices.
They wonder if stress played a role in the crash.
The first officer was alert
but didn't get distressed until the last few seconds.
Let's take a look at the captain now.
The analysis reveals that the captain was at a high level of stress
throughout the entire flight.
Yet he never tries to take control of the plane.
(PHONE RINGS)
Then investigators get a break in the case
from the air accidents investigative branch in the United Kingdom.
Right before take-off a passenger sent a text to a friend.
She thought the captain was drunk.
Good evening, ladies and gentlemen.
This is your captain speaking.
I'd like to welcome you onboard Aeroflot Nord Flight 891 - 821.
Our flying time to Perm will be 20 hours -
two hours and 30 minutes.
I'll talk to you again before we reach our destination.
Until then, sit back and enjoy the flight.
I think the captain sounds drunk.
Investigators learn that, just prior to take-off,
a passenger sent a text to her friend in the United Kingdom.
The passenger said she was scared
because the captain sounded totally drunk.
Let's cue the captain announcements.
Investigators listen to the CVR once again,
but this time with a horrifying new perspective.
Good evening - good morning.
He's confused. Play it again.
Good evening - good morning.
This is your captain speaking.
We've begun our descent into Perm
and should have you on the ground in 20 hours - uh, 20 minutes.
Local time is 4:50pm - am and the temperature is 7 degrees.
I'd say he's drunk.
The recording substantiates the passenger's text,
but the investigators still need hard evidence.
Finally.
The captain's muscle tissue has been tested for traces of alcohol.
The analysis confirms that there was alcohol
in his system before the crash.
He was drunk.
They found that the commander had raised levels of alcohol,
which would have been in his body before he took off.
Those levels would have impaired his judgment and his ability
to react accordingly in a stressful situation,
where the aircraft in effect was out of control.
Take it! Take it!
Take what? I can't do it either.
- What's going on! - Aeroflot 821, please come in.
COMPUTER: Terrain. Terrain.
- Pull up. - The malfeasance, neglect,
irresponsibility and incompetence that was demonstrated unilaterally
in this, it's just unbelievable.
The most shocking part of this entire
event was the fact that an airline could allow itself to either
evolve or maybe even devolve into such a multifaceted situation.
How could they allow themselves to do this?
And it killed 88 people.
In its final report, the investigative team
recommends a complete overhaul of the Russian aviation system.
The whole system needed to be looked at and strengthened in
terms of the regulations and how they train Russian pilots.
Three years after the crash, Aeroflot sold Aeroflot Nord.
It now operates as a separate airline called Nordavia.
Aeroflot does have quite a good safety record, and I assume that
they're working on the situation and have done a good job.
The accident rate's way down over what it used to be,
so hopefully things are moving in the proper direction.