Original subtitles

Narrator: On a challenging descent in the Himalayas...

Pilot: Landing on runway zero-two.

Questions or concerns?

Co-Pilot: No questions, no concerns, commander.

Narrator: A passenger jet collides

with the side of a mountain.

Pilot: What's happened! Co-Pilot: No, no, no, no, no!

Man: It really was a shocking moment.

Narrator: But when their most vital piece of evidence

doesn't deliver...

[Tape Hiss]

Man: This is it?

Narrator: Investigators scramble for answers.

Man: Could be weather?

Man: Loss of thrust?

Man: Intruder in the cockpit?

Narrator: But the accidental discovery of a valuable clue...

Man: Could it be?

Narrator: Points to the origins of what went wrong.

Pilot: Come on, come on, come on!

Man: That was the eureka moment in this investigation.

Flight Attendant: Ladies and gentlemen,

we are starting our approach.

Pilot: We lost both engines!

Flight Attendant: Put the mask over your nose.

Emergency descent.

Pilot: Mayday, mayday!

Flight Attendant: Brace for impact!

Controller: I think I lost one.

Man:...investigation starting into this tragedy...

Man: He's gonna crash!

Narrator: Pakistan International Airlines Flight 268

is en route to Kathmandu, the capital of Nepal.

The 2 1/2-hour flight from Karachi

is one of the few that flies to the Nepali capital,

situated 4,600 feet above sea level.

Landlocked between China and India,

Nepal is home to eight of the world's ten tallest peaks,

including the mighty Everest.

Kathmandu is a favorite destination

For travelers to the Himalayas,

many of whom are making their way to Nepal

for the start of the popular trekking season.

Mick Hardwick: Could I have a tea, please?

Narrator: Among them are Mick Hardwick

and his friend Dave Harries,

both mountaineering instructors back home in Britain.

Hardwick: Thank you.

Malcolm Creasy: I climbed with them through the Alps.

They were certainly very, very good climbers

in a variety of different disciplines in alpine work...

really top of the tree.

Narrator: They're on their way to climb Annapurna,

the 10th highest mountain in the world.

Creasy: Annapurna is certainly an ambitious program,

but it wasn't foolhardy.

It was well thought out and well planned.

It would have been a huge moment for them.

It would have been a trip of a lifetime.

Narrator: In the distance,

They get their first look at the Himalayas.

Hardwick: Hey, have a look at that.

Wow, finally!

Narrator: On the flight deck,

Captain Iftikhar Janjua is in command.

He's a former officer in the Pakistani Air Force

who's now a senior pilot instructor with the airline.

Captain Mohammad Hosain flew around the world

with Captain Janjua on many different flights.

Mohammad Hosain: I knew him for a period of about five years.

He had no airs about him, you know?

He was quite a simple person.

He was a family man.

He never smoked, he didn't drink.

In that way he was a straight guy.

Iftikhar Janjua: I don't like the look of the clouds ahead.

Narrator: The first officer is Hassan Akhtar,

a junior pilot with the airline,

with almost 1,500 hours flying the Airbus A300.

Janjua: How about we divert around them?

Hassan Akhtar: Yes, commander, agreed.

Narrator: It's nearing the end of monsoon season.

Large storms are still frequent along the route.

Janjua: Kathmandu, Pakistan 268.

We are 10 to 15 miles right of the track

to avoid a build up en route.

Narrator: To avoid the storm,

Captain Janjua notifies Kathmandu air traffic control

of his change to flight 268's approach.

Controller: Roger, 10 to 15 miles right of track, copied.

Janjua: It could get bumpy.

Let's keep them seated.

Akhtar: Agreed, commander.

Fasten seat belt sign is on.

[Chime]

Janjua: We're about to begin our descent into Kathmandu.

We are entering an area of turbulence,

and I request all of you to remain seated.

Creasy: The descent is always quite scary

because the plane seems to be descending forever.

You sort of lose track of where you actually are.

Janjua: We're expecting it to be a little choppy.

Hardwick: Well, here comes the mountains.

Creasy: Then you're on the runway and it's always,

uh, always a relief when the plane comes to a halt.

Janjua: I'll take over from here, Akhtar.

Akhtar: Yes, commander.

Janjua: I have control.

Akhtar: You have control.

Narrator: The first officer hands over control

of the aircraft to the captain.

Flight 268 leaves its cruising altitude

as it begins the approach into Kathmandu.

In 1992, Kathmandu airport

doesn't use radar to track its planes.

Every movement, planned or otherwise,

must be accurately reported by the flight crew.

David Mcnair: In the absence of radar,

it requires good communication

between the aircraft and the air traffic controller.

They have to communicate very carefully.

Akhtar: Pakistan 268 approaching overhead,

uh, Simra 1-5-0.

Controller: Pakistan 268, descend to 11,500,

no delay expected.

Akhtar: Roger, sir.

Down to 11,500.

Andrew Robinson: The problem with Kathmandu

is that you have a range of mountains

to the south that you have to get over,

and then you have to drop down quite steeply

in order to be able to land at the threshold of the runway.

There is a danger of arriving at the threshold too fast

or even a little bit high.

Narrator: The mountains surrounding Kathmandu

require pilots to make what's known as a stepped approach.

Pilots must descend to a series of lower altitudes,

at certain distances from the airport.

Janjua: We can expect descent clearance by 16 miles.

Descent angle is steep,

So we need to be at flaps 15 by 16 miles.

Landing on runway zero-two,

watch for stray animal and birds.

Questions or concerns?

Akhtar: No questions, no concerns, commander.

Controller: Pakistan 268, report 1-6 miles.

Wind 1-8-0, expect sierra approach.

Akhtar: Roger, call you at 1-6 miles.

Expecting sierra approach.

Sierra approach, commander.

Janjua: Here it is.

Watch my levels.

Narrator: The details of the stepped approach

are laid out on a chart for the pilots.

Mcnair: The approach chart is designed

to keep you clear of terrain.

So you had to follow the approach chart.

Narrator: As flight 268 begins its final approach

towards Kathmandu,

passengers and crew prepare for landing.

Hardwick: Well, sun and blue skies would be nice.

Controller: Alpha Charlie Hotel, surface wind 2-0-0, 0-5.

Akhtar: Pakistan 268 is at 1-6 miles, 11,500.

Narrator: 16 miles from the airport,

the pilots report their altitude as 11,500 feet.

Controller: Roger, Pakistan 268.

Report 1-0 miles.

Akhtar: Roger, call you at 1-0 miles, Pakistan 268.

Narrator: The crew works its way through the steps

towards Kathmandu, approaching from the south.

They should be touching down in about 6 minutes.

Controller: Alpha Charlie Hotel, continue to taxiway number two.

Akhtar: Pakistan 268 is at ten miles.

Controller: Report your level.

Akhtar: We crossed out of 8,500... 200 now.

Controller: Roger, clear for final.

Report 4 miles, runway zero-two.

Akhtar: Will call you at 4 miles.

Pakistan 268.

Cleared for final, runway zero-two.

Janjua: Runway zero-two.

Narrator: Flight 268 is now less than ten miles from the runway.

Air traffic control waits

for the flight crew's next position report.

♪

Three minutes go by.

♪

Flight 268 should have reported

that they've reached the next step by now.

Controller: Pakistan 268, report your position.

Pakistan 268, report position.

Pakistan 268, tower.

Pakistan 268, this is tower.

Narrator: As the minutes tick by...

Air traffic controllers come to a horrifying realization...

Flight 268 is missing somewhere in the Himalayas.

It doesn't take much time

for Kathmandu air traffic controllers to get word

that PIA flight 268 has crashed somewhere in the Himalayas.

Within hours, the plane's wreckage is found

On the side of a mountain.

The flight was carrying more than 20 tons of fuel,

and the plane is completely consumed by fire.

All 167 people on board have died.

Reporter: Tonight investigators refuse to speculate

on possible causes of the crash.

So dangerous are the conditions...

Creasy: We were all back in North Wales,

and news filtered through into the office.

We just sort of stared in disbelief, really.

We couldn't believe it.

You hear of these things happening,

but when it happens to people you've been in contact with

on a daily basis year in year out

and worked with on the cliffs and the crags, just disbelief.

Narrator: As the flames die down,

Nepal faces a chilling reality:

A passenger jet has crashed near the Kathmandu runway

for the second time in two months.

The first was a Thai Airways Airbus with 113 people on board.

Canadian accident investigator Dave McNair is already in Nepal

leading the Thai Airways investigation.

Mcnair: There hadn't been an accident in Kathmandu

for many, many years.

There was the one accident that happened back in July,

and then a second accident,

a major aircraft in the same place,

and it really was a shocking moment.

Investigator: Yeah. OK.

Narrator: Within hours, the Nepalese government

launches an investigation into the crash of Flight 268.

Investigator: We need to get there

as soon as the weather clears.

Narrator: Already stretched thin

by the Thai Airways investigation,

the Nepalese ask British investigators for help.

Investigator: Thanks for coming, Andrew.

Narrator: Andrew Robinson

from Britain's Air Accidents Investigation Branch

is one of the investigators assigned to the case.

Robinson: Let's see what we're dealing with here.

My role in the investigation was to look at the...

the engineering aspects of the accident,

so I would be looking at the site,

the wreckage distribution, the wreckage itself,

the components within it,

and trying to work out what the impact attitude was,

whether all the aircraft was present at the impact site,

that sort of thing.

Narrator: Kathmandu airport is the main hub

of Nepal's tourist industry.

The pressure is on the team to figure out

what caused this accident as quickly as possible.

Robinson: We wanted to find out obviously

if there was something wrong with Kathmandu airport

or procedures involved in approaching or landing at it.

So, yes, there was a huge concern

within the aviating community.

Narrator: The Nepalese government deploys the military

to help investigators get to the remote crash site,

Which is more than 7,000 feet above sea level.

Mcnair: I was part of the team to go up there

to look at the initial, uh, wreckage survey.

It was quite of a perilous drive to get there.

We got to the base camp,

and then we had to walk about 2 kilometers up a path

to get to the site.

It was an emotional walk because as we were walking up,

people are bringing the remains down.

When we first encountered the wreckage site...

You couldn't even recognize an airplane except for the tail.

And of course you could see some of the souvenirs people had

were lying on the ground...

A little child's sock was there, so, you know that related you

to people that were on the airplane.

But, uh, in this case, uh,

it was just the aircraft was just totally destroyed.

It was just a complete obliteration of the aircraft.

Narrator: The team begins examining the wreckage.

But conditions are treacherous.

Robinson: The aircraft had crashed

into the side of a mountain about 150 feet from the top,

and getting about on the site to inspect it

was actually quite difficult

because the average slope was about 45 degrees.

Narrator: Investigators quickly conclude

that it's too dangerous to examine the wreckage on site.

Mcnair: The actual workers were Nepalese

who had to deal with some steep slopes

and had to work very, very carefully

to make sure that nobody was injured on the site.

Narrator: As the investigation gets underway,

one thing is obvious: Flight 268's final altitude.

Investigator: This is the location of the crash site,

9 miles south of the airport.

The aircraft collided with the mountain

at an elevation of 7,280 feet.

Narrator: Investigators plot the location and altitude

of the crash site.

Investigator: Just below the summit.

Robinson: Where should they have been?

Investigator: Can you pass me that approach chart, please?

Thank you.

At 10 miles out, he should have been at 8,200 feet.

Robinson: How do you hit a mountain

you're supposed to clear by 1,000 feet?

Mcnair: You know it hit the mountain.

There's no doubt about that.

But you don't know why it was as low as it was

when it hit the mountain.

Narrator: As yet more mystery swirls around flight 268,

a makeshift morgue is set up outside the airport.

The people of Kathmandu must come to terms

with a second tragedy in as many months,

and pressure builds to find out why that happened.

Nepalese soldiers have retrieved the aircraft's black boxes

from the wreckage of PIA flight 268.

Investigator: Put that over there, please.

Narrator: The digital flight data recorder, or DFDR,

contains information

About critical aircraft operations and performance.

Investigator: They look pretty banged up.

Narrator: The cockpit voice recorder

records conversations between the pilots.

They'll both be sent to France

where the data will be downloaded and analyzed.

Mcnair: Flight recorders are extremely vital

to investigations.

The most important part is it really brings you closer

to understanding the entire reason for the accident.

Narrator: But until they get the data,

investigators must look elsewhere for clues.

They hope the air traffic controller

can provide some insight.

Controller: I've been running through

every conversation we had and studying my notes.

Investigator: Does anything stand out?

Controller: They had to deviate around some bad weather.

[Coughing]

Janjua: Kathmandu, Pakistan 268.

We are 10 to 15 miles right of the track

to avoid a build-up en route.

Narrator: The controller tells investigators

that the crew reported some storm clouds

on the way to Kathmandu.

Robinson: It's usually very hazy in the Kathmandu valley.

In most conditions where you've got mountains

you invariably have clouds.

Controller: That's common this time of year.

Investigator: anything else after that?

Controller: Standard position reports, by the book.

Akhtar: Pakistan 268 is at ten miles.

Controller: Report your level.

Akhtar: We crossed out of 8,500... 200 now.

Controller: Roger, clear for final.

Report 4 miles, runway zero-two.

Akhtar: We'll call you at 4 miles, Pakistan 268.

Controller: He said he'd contact me when he got 4 miles out,

but I never heard from them after that.

Robinson: Ok, let's see what the wreckage can tell us.

Mcnair: When an aircraft is destroyed,

there are still things you can get from the accident site.

Narrator: Investigators consider the possibility

the jet was flying out of control when it crashed.

They scrutinize the crash site for clues.

Robinson: Look at this.

The right wing impacts up here.

Narrator: A large scar shows Robinson

precisely where the wings hit the side of the mountain.

He also notices that just over 4 feet below the impact scar,

the top of a tree has been cut cleanly.

Robinson: The wing couldn't have cut that tree, so what did?

Mcnair: The aircraft cut some tree branches,

so you can actually use that to measure angles of impact.

Then you use other evidence

to find out what happened to the airplane.

Robinson: What about...

the flaps?

Investigator: Fully extended,

exactly 1.3 meters below the wing.

Narrator: For the team, it's a critical clue.

As the Airbus A300 slows for landing,

its wing flaps extend by as much as 25 degrees.

Hanging below the wings, the extended flaps

would shave the top of the tree as it slams into the mountain.

Robinson: Wings level, no pitch down, flaps extended.

In other words, the exact landing configuration.

And this plane was absolutely not out of control.

Janjua: Flaps 10.

Akhtar: Flaps 10.

Mcnair: This is an indication that in fact the crew

was deliberately flying it there.

But what was abnormal

was the fact the airplane was being flown too low.

The question is: Why was that?

Narrator: To answer that question,

the team creates a list of every conceivable scenario,

based on the evidence they've collected so far.

Investigator: Any thoughts?

Investigator: Loss of thrust?

Akhtar: Cleared for final, runway zero-two.

Janjua: Runway zero-two.

[Alarm Beeping]

Akhtar: Loss of engine number one.

[Beeping]

We're losing number two as well.

Narrator: Investigators consider a loss of thrust

in both engines.

Janjua: Ok, watch my altitude.

Janjua: Come on, come on, come on!

Akhtar: 7,800.

Janjua: Initiate restart, either engine.

Narrator: And a rapid loss of altitude...

Akhtar: 7,500. We're not gonna make it!

Narrator: Leading to the collision with the mountain.

Robinson studies what's left of the plane's engines.

♪

Robinson: Only one way this got in so deep.

Narrator: The damage and debris inside tell Robinson

the fan blades were spinning when they hit the ground.

And further examination of the device that controls fuel flow

shows they were at the lowest thrust setting... flight idle.

That's precisely where they should be

for an A300 descending towards the runway.

Robinson: The thrust from the engines

was symmetrical and at low power.

There was no indication of loss of control,

so that was dismissed.

So we then had to sit down and think of reasons

why the pilot might have been too low.

Narrator: With mechanical failure ruled out...

Investigator: OK, not the engines.

Narrator: And the black box data still in Paris...

Investigator: What else?

Narrator: Investigators turn their attention

to what was happening in the cockpit.

Robert Bor is an aviation psychologist

who has studied the course of this investigation.

Robert Bor: Accident investigators

will typically approach this kind of investigation

As though they were detectives,

and they're gonna raise a wide range of questions,

hypotheses that they will want to test out.

Robinson: OK, uh, what about an intruder in the cockpit?

Mcnair: Unlawful interference is something that's around us.

It's everywhere.

We spend our lives dealing with it

every time we check in to the airport.

So we know it's out there.

Narrator: The team now wonders:

Were the 167 people on board

victims of a terrorist attack?

Investigators are concerned

an act of terrorism may have brought PIA flight 268

to a violent end in the Himalayas.

[Explosion]

Pakistan International Airlines

has been on high alert for over a decade

since one of its planes was hijacked for 13 days in 1981.

As a result, the airline routinely places armed guards

On high-risk routes.

Investigator: There were four air guards on this flight.

Narrator: They turn to the passenger manifest

for more information.

Investigator: Here, here, here and here.

Robinson: As often happened in Pakistan Airways flights,

there were a number of security guards on board,

which would probably tend to suppress unlawful interference.

Narrator: The controller reported

that the first officer's final radio call,

just 32 seconds before impact, was calm and professional.

Akhtar: We'll call you at 4 miles.

Pakistan 268.

Narrator: No hint of a struggle.

Bor: That helps us to understand

that on the flight deck things were pretty normal.

The crew were probably, therefore,

not being interfered with by a hijacker.

Investigator: I think we can rule out an intruder.

Now what?

Robinson: Could be weather?

Mcnair: In Kathmandu there are quite often build-ups of clouds,

and they can develop into thunderstorms

or cumulonimbus types of clouds,

and the suspicion was maybe

there was some sort of cloud like that on the approach.

Investigator: This is everything from the time of the accident.

Narrator: Investigators examine weather conditions

throughout the flight.

The report was cloudy with a potential for storms.

But because the crew had deviated around bad weather...

Janjua: Kathmandu, Pakistan 268.

We are 10 to 15 miles right of track

to avoid a build-up en route.

Narrator: It's unlikely they then flew into a thunderstorm.

By now, the team has ruled out all possible external factors

for this accident.

Investigator: Flaps were out, engines spinning, no intruder,

no serious weather on approach.

Narrator: They're left with only one conclusion.

Investigator: They must not have known

that they were flying too low.

Akhtar: Cleared for finals, runway zero-two.

Janjua: Runway zero-two.

Akhtar: Next altitude is 6,800 at 8 miles.

Now crossing through 7,500.

7,400.

Janjua: What's happened? Akhtar: No, no, no, no!

Bor: It's clear in this situation

that the pilots had built up a picture of the outside world

that is not true and accurate, which leads to the crash.

However, we have to ask questions why that may be.

Narrator: Investigators look into two possibilities

for the flight's dangerously low altitude.

Robinson: Either they ignored their chart

and were doing a visual approach,

or they somehow misread the chart.

Investigator: Nothing else makes sense.

Robinson: We had no way of knowing why it was too low,

so that became a matter of studying the data

And having a general roundtable discussion.

Alright, let's start with the visual approach.

Controller: Roger, Pakistan 268, report 1-0 miles.

Akhtar: Roger, call you at 1-0 miles, Pakistan 268.

Janjua: We can save some time by going visual.

Watch my speed.

We should soon see the runway.

Narrator: On a visual approach,

pilots fly based almost entirely on what they can see...

Akhtar: Yes, commander, visual to runway zero-two.

Narrator:...rather than a pre-determined route.

Janjua: Flaps 10.

Akhtar: Flaps 10.

Janjua: Flaps 15.

Akhtar: Flaps 15.

Narrator: In many instances,

visual landings are easier for pilots...

Janjua: Watch for the runway.

Narrator: But with a greater risk of human error.

Janjua: What's happened? Akhtar: No, no, no, no!

Investigator: Agh...

It's... It's possible, but...

Almost total cloud coverage throughout the entire approach.

Plus, they knew the terrain.

The captain made this approach at least seven times,

the first officer, five.

Narrator: Investigators conclude it's highly unlikely

the flight crew attempted a visual approach in thick clouds.

Bor: It's a complicated arrival.

It requires a step down

at various points toward the runway threshold,

and perhaps most significantly, the meteorological conditions

were not conducive to a visual approach.

Controller: Pakistan 268, report 1-6 miles.

Narrator: The only theory left

is that the pilots somehow misinterpreted

their approach chart.

Akhtar: Sierra approach, commander.

Janjua: Here it is. Watch my levels.

Bor: Everything was working, technically.

There didn't appear to be any interference

on the flight deck by anyone.

And so the only conclusion that we can take from this

is that for some reason

the pilots had clearly misinterpreted data.

Investigator: Alright. Let's look at this.

Narrator: Investigators hope the flight's black box data,

back from Paris, will help solve the mystery.

They look at the plane's flight path

as the crew prepares for landing.

Investigator: They started their descent.

At 16 miles out they're at 10,500 feet,

then down to 9,500 at 13 miles, 8,200 at 10 miles,

then quickly down to 7,500 until impact at 7,280.

Narrator: The data reveals an astonishing fact.

Robinson: So 1,000 feet too low, right from the get-go.

Narrator: The approach to Kathmandu

is one of last places on earth

a pilot would risk flying too low.

Robinson: Wait a minute.

There you go, perfect match.

They were flying the approach, but one step ahead.

What the aircraft flew

was pretty much what the chart said,

except that the pilot had got one step ahead of himself.

So he's flying the correct altitude for the next position,

which was a sort of eureka moment, I think,

in this investigation.

Investigator: He's adjusting his descent

to hit the lower altitudes.

It's no accident.

Robinson: We obviously started to wonder

why this should be the case.

Narrator: Still working in the shadow

of the Thai Airways crash just two months earlier...

Investigator: Are we ready?

Let's hear it.

Narrator: Investigators now hope

the Pakistan Airways cockpit voice recording

will shed light on what happened in the cockpit

In the lead-up to the fatal collision.

♪

But as the team begins listening to the CVR,

they get a gut-wrenching shock.

[Beep]

[Tape Hiss]

Investigator: This is it?

♪

Narrator: The cockpit voice recording of PIA Flight 268

is playing the last thing investigators want to hear:

Silence.

But then...

Janjua: We are entering an area of turbulence,

and I request all of you to remain seated.

Narrator: The tape has recorded

the announcements made to the cabin

and conversations with controllers,

but not the conversations between the two pilots.

Investigator: OK.

So nothing from the cockpit mic.

Narrator: It's a major setback.

Investigator: Back to the drawing board.

Narrator: Without the full cockpit voice recording,

investigators need to find other ways of understanding

why the pilots of Flight 268 were flying 1,000 feet too low

at every step of their approach.

Bor: We have to therefore build a picture

of what might have been going on in their minds,

in the relationship between the two pilots,

and in their relationship between themselves,

the physical environment, and air traffic control.

Investigator: What if the problem

is the actual approach chart itself?

Narrator: To avoid the mountains surrounding Kathmandu,

pilots follow an approach chart...

about the size of a large postcard.

It provides the specific altitudes pilots must take

at set distances from the airport.

They study the same chart used by the flight crew.

Robinson: So, is, let's say, 8,200 feet the right altitude

For 10 miles or 8 miles?

It's hard to say.

Investigator: Even harder when it's actual size.

Robinson: The operations team spent a lot of time

looking at the chart that the crew had been using.

They concluded that there was

a large amount of information on it.

It was, um, it was a lot of clutter.

Narrator: Investigators need to know

how the crew would have prepared themselves

for the complicated approach.

They examine the cockpit layout

of an identical Pakistan International Airlines

Airbus A300.

Robinson: There's no place to clip an approach chart here.

Most aircraft have little clips

on the control column to attach the approach plates to.

Now, this particular aircraft didn't.

There is just here.

Now only the captain can see it,

And he'd have to keep turning his head.

Unlikely they used that.

More likely he put it here.

Narrator: The other clip is a full three feet away

from either pilot.

Robinson: That's not much better.

It's almost impossible to read,

and that handle is blocking the descent profile.

Narrator: They learn that Pakistan International Airlines

has only two places for pilots to clip their charts.

Both positions make it very difficult

to read a 4-inch-wide piece of paper.

Robinson: It's difficult to make a quick reference

if you're having to sort of look to the right or to the left

for a chart.

Could it be?

Narrator: Then, quite by accident,

the investigators discover a key clue

regarding the pilots' misreading of the approach chart.

Robinson: If you pick up the chart

And happen to put your thumb over the 11,500-foot mark

for 16-nautical-mile marker,

in that case it might have guided his eye

to the next height fix,

and he might assumed that that was the correct height

for the 16-mile marker point.

Robinson: This definitely makes it look like 10,500

is the correct altitude at 16 miles.

Narrator: Robinson finally has a theory he can put to the test.

Akhtar: Kathmandu tower, good afternoon, Pakistan 268,

2-5 miles at 11,500.

Narrator: Just a few minutes before impact,

the first officer reports being 25 miles from the airport,

at the correct altitude of 11,500 feet.

Controller: Pakistan 268, report 1-6 miles.

Wind 1-8-0, expect sierra approach.

Akhtar: Roger, call you at 1-6 miles.

Expecting sierra approach.

Sierra approach, commander.

Narrator: But when the captain looks at the approach chart,

His thumb may have obscured the correct next altitude.

Janjua: Here it is. Watch my levels.

Narrator: Now, instead of maintaining 11,500 feet,

Captain Janjua dials in the next altitude on the chart...

Janjua: Descending to 10,500.

Narrator:...oblivious that his plane's approach

is now one step ahead.

The crew has now made a fatal mistake,

unaware the airliner is now descending

towards a violent collision with the side of a mountain.

Robinson: So that was where it all started.

Narrator: Investigators now pursue the new theory,

that the pilots of Flight 268

misread the altitudes on a cluttered approach chart.

Robinson: At 16 miles they should be at 11,500,

but they've descended to 10,500.

Narrator: The team has a surprising realization.

Robinson: But then they report being at 11,500.

Narrator: At the 16-mile mark,

the first officer reports the altitude they should be at...

11,500 feet.

Akhtar: Pakistan 268 is at 1-6 miles, 11,500.

Narrator: Instead of 10,500,

the lower altitude they're actually at.

The investigators have uncovered a new mystery

that goes right to the heart of what went so horribly wrong.

Robinson: Why did they descend to 10,500

and then report being at 11,500?

Narrator: Andrew Robinson's team returned to the flight data,

hoping to understand why the pilots of flight 268

misread and misreported their approach altitudes

before the crash.

Robinson: A slat extension, a frequency change

and then flaps and landing gear.

Investigator: He was a busy guy.

Bor: It's a fast and steep approach,

and unless you're a pilot

with considerable experience flying this route,

maybe several times in a week, it's going to be very testing.

Janjua: Descending to 10,500.

Janjua: Initiating descent.

Narrator: Investigators now believe

that as the distracted flight crew approached 16 miles...

Janjua: throttles to flight idle.

Slats 15.

Narrator: Their attention was consumed

by the demands of the busy descent.

Janjua: Flaps 10.

Akhtar: Flaps 10.

Janjua: Flaps 15. Landing gear down.

Narrator: By now, the captain has already dialed

the flight's descent 1,000 feet too low.

Akhtar: Gear down. Three green.

Janjua: We're at 16. Report our position.

Akhtar: Pakistan 268 is at 1-6 miles.

Narrator: Investigators think the first officer

hastily misreports the altitude on the approach chart...

Akhtar: 11,500.

Narrator:...without double-checking his altimeter.

Then, captain Janjua is too busy to notice the discrepancy

Between the reported and actual altitudes.

Bor: In quite a stressful environment,

such as the arrival at this airport,

the build-up of pressure inside the pilot

must be quite considerable,

and their capacity to assimilate,

take in information, read what's going on around,

is going to be severely taxed.

Investigator: Can we hear his next report, please?

Akhtar: Pakistan 268 is at ten miles.

Controller: Report your level.

Akhtar: We crossed out of 8,500... 200 now.

Investigator: When he makes this report, he's at 8,100 feet.

Akhtar: We crossed out of 8,500...

200 now.

Controller: Roger, clear for final.

Report 4 miles, runway zero-two.

Narrator: Both pilots seem to have made mistakes.

But air traffic control could have caught them

and sounded the alarm.

Bor: Why did the air traffic controllers not speak up?

Why did they not say anything?

Narrator: Investigators head to Kathmandu airport

to find out why air traffic controllers

didn't warn Flight 268 it was flying too low

before it crashed.

Controller: I did not know his exact position,

so I had no way of knowing what the terrain below him was.

Mcnair: In this case without radar,

it is really the responsibility of the crew

to make sure of where they are flying and their approach.

Narrator: They also learn that pilots flying into Kathmandu

often reported being at altitudes

lower than the ones specified on the chart.

Controller: When the mountaintops

are covered in clouds,

pilots will sometimes dip under them

and fly over this valley instead.

Akhtar: We crossed out of 8,500... 200 now.

Narrator: If the pilots of Flight 268

Had detoured around the mountain,

8,200 feet would be a safe altitude.

Bor: Radar coverage in this area was not well developed,

and therefore it was very much a procedural approach

and not one that relied on inputs

from air traffic controllers themselves.

They were recipients of information

and not really guiding the aircraft in.

Investigator: It all starts with the initial misreading

of the chart and spirals forward from there.

Narrator: Investigators believe they've finally developed

an explanation for how the tragic accident unfolded.

Akhtar: Sierra approach, commander.

Narrator: The first mistake is made before the 16-mile marker,

where the captain likely misreads the approach chart...

Janjua: Here it is. Watch my levels.

Narrator: And enters the altitude for the 13-mile marker,

one step ahead.

Janjua: Descending to 10,500.

Landing gear down.

Akhtar: Gear down. Three green.

Janjua: We're at 16. Report our position.

Narrator: Then, likely distracted by the busy approach,

the first officer misreports their altitude.

Akhtar: Pakistan 268 is at 1-6 miles.

Narrator: He reports where they should have been...

Akhtar: 11,500.

Narrator:...not where they actually are.

Investigators believe that if the captain

had caught and checked that discrepancy,

the flight's outcome might have been completely different.

Robinson: At that point there was scope to correct

and get back on track,

but the profile suggests

that, uh, they thought they were on the correct altitude,

and everything stemmed from there.

So they carried on being that one step ahead.

Narrator: Flight 268 remains 1,000 feet

below the recommended safe altitude

for what's left of its fatal descent.

Akhtar: We crossed out of 8,500...

200 now.

The next altitude is 6,800 at 8 miles.

Now crossing through 7,500.

7,400.

Janjua: What's happened? Akhtar: No, no, no, no!

Investigator: Three minutes after they first

misread the chart, they impact the ground.

Bor: What is quite striking

is that it is a very difficult approach,

and in spite of that, the pilots

are actually operating effectively, but not safely.

This is at the heart of crew resource management,

and that has failed in this accident.

Narrator: In the end,

if the plane had been just a few hundred feet higher,

it would have missed the mountain,

and 167 lives would have been spared.

In the aftermath of the flight 268 tragedy,

investigators make a number of recommendations

To prevent another accident due to a misread approach chart.

Chief among them is simplifying the Sierra approach itself,

to make it less complex and challenging.

They also recommend installing air traffic radar at Kathmandu

and suggest Pakistan International Airlines

install clips on the control columns

of all its A300 airplanes.

Robinson: Minor things like the provision of chart clips,

installation of radar...

It's a gradually improving picture,

and things hopefully still will continue to improve.

Narrator: A memorial to the victims of Flight 268

stands at the foot of the mountain where it crashed.

Creasy: They're still remembered by people of my generation.

They're still remembered as people who did a lot

and would have done a lot more

in the world of mountain training.