Original subtitles

Automation: gearbox pressure.

[Rattling]

Man: Ah, hell.

Man: Brace!

Narrator: Off the coast of Newfoundland...

a helicopter crashes into the ocean.

Stephen Harper: When you see a tragedy like this,

it makes many, many people across the country

understand the sorrow.

Narrator: 17 people are dead.

Remarkably, one man survives.

Man: Look at it.

Somehow he gets out in a helicopter

that is sinking past 30 feet.

Man: It was a long descent.

Eventually my arms broke the surface.

Man: It's very important to analyze

what affected their ability to exit the aircraft.

Narrator: What investigators uncover has a critical impact

on the safety of every helicopter flying over water.

Man: That man is lucky to be alive.

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: Cougar Flight 91 prepares for liftoff.

This is a commuter run from St. John's, Newfoundland,

to offshore platforms in the Hibernia oil fields.

Captain Matthew Davis is at the controls.

In a helicopter, unlike an airplane,

the captain sits on the starboard or right-hand side.

Matthew Davis: Next stop, Sea Rose.

Narrator: First Officer Tim Lanouette

is in the left-hand seat.

A veteran Navy helicopter pilot,

he's a newcomer to civilian aviation.

Tim Lanouette: Ground, Cougar 91, request takeoff.

Controller: Cougar 91, depart to the south, then on course.

Cleared for takeoff.

Narrator: The helicopter they're flying is a Sikorsky S-92.

It's a large aircraft

with room for 17 passengers and their gear.

Philip Greenspun: The Sikorsky S-92 was kind of designed

for this mission.

You can look at the S-92 as kind of a merging of their best ideas

from the U.S. Army's Black Hawk helicopter.

Narrator: The Hibernia oil fields

are 170 miles from St. John's.

It would take 15 hours to get there by boat.

Davis: Autopilot engaged.

Lanouette: Autopilot engaged, copy.

Narrator: By helicopter, it's only a 90-minute flight.

So for workers on oil rigs,

it's the primary mode of transportation.

Davis: We only have two for the Sea Rose?

Lanouette: Affirmative. And 14 for Hibernia.

Davis: Let's lighten the load early.

Alpha routing.

Lanouette: Copy.

Gander, Cougar 91.

Taking a look at the ops plan here.

We would like to amend our flight plan.

We would like to go alpha routing,

Hibernia first, then Sea Rose.

Narrator: A minor change in plan.

Cougar 91 will travel to the Hibernia rig

and then proceed to the Sea Rose platform.

Controller: Okay.

Cougar 91 is cleared to Hibernia via the amended route.

Narrator: The flight is almost full.

The 16 passengers are service workers,

the cooks and cleaners of the offshore world.

Robert Decker is a weather observer

for rigs in the North Atlantic.

He's made this flight 50 times over the past three years.

Greenspun: Because there are so many constraints

on the amount of space and the amount of weight

that a helicopter can carry,

the amenities in the helicopter

are just stripped down to the bone.

So you're not gonna find any of the amenities

that you would find in an airbus or a boeing.

Decker: It's boiling in here!

Narrator: High-visibility survival suits are mandatory

on all helicopter flights over the open sea.

Greenspun: Unlike an airplane,

if you have to ditch in the water for any reason,

the aircraft will not float.

An airplane will float

for, you know, anywhere from five minutes to many hours.

The helicopter will simply sink like a rock.

Narrator: 28 minutes into the flight,

Cougar 91 has leveled off at the standard cruising altitude.

Davis: 9,000 feet.

Lanouette: 9,000 feet, copy.

Three weeks on and three weeks off.

Life on a rig.

Davis: I don't know what's worse.

Three weeks off, I'd get bored.

Automation: gearbox pressure.

Gearbox pressure.

Davis: MGB oil pressure.

Narrator: Oil is the lifeblood of a helicopter.

A problem with the oil pressure can be catastrophic.

Davis: Emergency checklist.

Narrator: While first officer Lanouette

looks for the checklist...

Davis: Autopilot off.

Narrator: Captain Davis disengages the autopilot

so he has complete control of the aircraft.

Then he does what all captains hope they will never have to do.

Davis: Gander Center, Cougar 91.

Mayday.

Controller: Cougar 91, go ahead.

Davis: Sir, we have a main gearbox oil pressure problem.

Request immediate clearance back to takeoff.

Controller: Cougar 91, roger.

You can make a right turn heading three-zero-zero.

Narrator: The controller contacts

the search and rescue headquarters in Halifax.

Controller: Halifax, Gander center.

We have a mayday call from a Sikorsky S-92,

currently on return to St. John's.

Main gearbox problem.

Narrator: Flight 91 is 54 miles from land.

It will take them 30 minutes to reach shore.

Captain Davis alerts Cougar helicopter's dispatch center

in St. John's.

Davis: Dispatch, Cougar 91.

We're coming back to St. John's.

Dispatch: Cougar 91, dispatch.

Roger. Keep us advised.

Davis: I'm taking her down to the water.

Lanouette: Roger.

Davis: Checklist?

Lanouette: I'm still trying to find it.

It might be at the back of the book.

Davis: Main gearbox failure.

We should be getting smells, vibrations.

I don't smell anything.

What about the back?

Lanouette: Nothing.

Nobody's doing anything in the cabin.

Narrator: Cougar 91 is descending

to just under 1,000 feet.

The helicopter is now 52 miles from St. John's.

Controller: Gander center for Cougar 91.

Which runway would you like me to set you up for?

Davis: I'm going for the nearest piece of terra firma

I can get to, whatever I see first,

if it's Cape Spear or a parking lot.

Lanouette: Okay, I got the checklist.

MGB pressure below 35 psi.

Narrator: The pressure gauge indicates

That the main gearbox oil pressure

is well below the normal range of 45 to 70 psi.

Lanouette: Confirmed.

MGB oil temperature greater than 130 degrees.

Narrator: But the reading on the temperature gauge

is not what it would be if there were a loss of oil pressure.

Lanouette: Your temperature looks normal.

The problem could be with the sensor.

Controller: Cougar 91, Gander.

Search and rescue has been notified

and if you have the time,

I'll take the souls on board and fuel remaining.

Davis: Okay, two-nine-nine-two, we have, uh, about three hours

of fuel on board and 18 persons on board.

This is the captain.

We've had a major technical problem,

and at this time I'd ask for everyone

to prepare your survival suits.

We are heading for the closest land.

♪

Dispatch: Cougar 91, dispatch.

Davis: Go for 91.

Dispatch: Rescue is asking if ditching

is imminent, probable or possible.

Davis: Dispatch, 91. Ditching is possible.

Dispatch: If possible, can you update our senior pilot

on the situation?

Davis: Dispatch, I think we have an oil pump problem

or an oil pressure sensor problem.

Dispatch: Matt, can you describe the symptoms?

Davis: The gearbox oil temperature is still normal.

I don't think we've lost all the oil in the system.

I'm on a heading for closest landfall,

if this goes south on us.

Narrator: Cougar 91 is still 35 miles from the nearest land.

But now...

[Rattling]

Davis: Ah, hell.

Dispatch, we're ditching.

Lanouette: Ditching.

Airspeed 122, Matt.

Davis: I think it just kicked on me.

Lanouette: Okay, nose up, nose up.

Alright, we're turning.

Davis: Call it in.

Lanouette: We're getting prepared to, uh, ditch.

Ditching!

Ditching! Ditching! Ditching! Ditching!

500 feet.

You got this.

Get it pointed downwind.

Brace! Brace! Brace! Brace!

♪

♪

Narrator: The passengers and crew of Cougar 91

are now trapped inside a sinking helicopter.

One of the most advanced helicopters in the world

has dropped out of the sky

into the icy North Atlantic off the coast of Newfoundland.

Harper: When you see a tragedy like this,

it makes many, many people across the country

understand the risks and understand the sorrow.

Narrator: 17 people are dead.

There is only one survivor.

Robert Decker, a young offshore oil worker,

is rushed to the hospital with life-threatening injuries.

[Siren]

The close-knit offshore oil community is shattered

and looking for answers.

Man: It's hard, you know, to believe that it happened

to somebody within your community.

Wendy Tadros: This was an international accident.

There were about 80 Sikorsky S-92s operating worldwide,

and they were operating in every extreme environment

you can imagine.

We really needed to drill down and figure out

what had happened and why it had happened.

Narrator: The answers lie 554 feet beneath the surface

of the Atlantic Ocean.

Within hours of the crash,

Canada's Transportation Safety Board assembles a team

to recover the wrecked helicopter

and discover the cause of the crash.

Mike Cunningham will lead the investigation.

Cunningham: We were looking at a major accident,

and it was gonna require a significant response

from the TSB.

Narrator: The Transportation Safety Board is provided

with the Atlantic Osprey,

a vessel designed to service offshore oil rigs.

Allan Chaulk will lead the recovery effort.

Allan Chaulk: It's one of the best pieces of equipment

in this area.

When it comes to recovery, it's very well equipped.

Narrator: Using the last known waypoints for Cougar 91,

the ship locates the wreckage within hours.

Chaulk: I'd say our number one priority

was to recover the victims,

and then the priority became the multipurpose flight recorder

and the remainder of the wreckage.

Narrator: Remotely operated vehicles, or ROVs, are deployed

to recover the victims and retrieve the wreckage

from the ocean floor.

Cunningham: Yeah, this'll do.

Narrator: The TSB sets up operations

in a hangar at St. John's International Airport.

Cunningham: Yeah. Tell them all the wreckage comes in here.

♪

Controller: There was no indication of any problems

until the mayday came in.

Cunningham: Right, that's what we heard as well.

Narrator: While Cunningham waits for the wreckage

to be recovered, he interviews the air traffic controller

who last had contact with the doomed helicopter.

Cunningham: We talked to the air traffic controllers

to find out how things went on their end.

We look at their comm tapes, their radar tapes.

Controller: The mayday came in at 09:45.

Davis: Gander Center, Cougar 91. Mayday.

Controller: Cougar 91, go ahead.

Davis: Sir, we have a main gearbox oil pressure problem.

Narrator: Cunningham gets his first clue.

Cunningham: He said that they had lost

all main gearbox oil pressure,

so this was important information for us.

Narrator: The main gearbox uses power from the engines

to spin the main and tail rotors.

Like the transmission in a car,

the gearbox requires a constant supply of oil

to keep moving parts lubricated.

Cunningham: The main gearbox in a helicopter

is a very critical piece of equipment.

The failure of the gearbox would mean a loss of lifting power

from the main rotor,

the loss of directional control to the tail rotor.

Narrator: Cunningham needs to find out what caused

the oil pressure warning the crew reported.

Could there have been an oil leak in the main gearbox?

Davis: Request immediate clearance back to takeoff.

Cunningham: So the captain requested clearance

Back to St. John's, and that's 45 nautical miles.

How long would that take to fly?

Controller: 30 minutes.

Cunningham: But, uh, Cougar 91 went down in, uh...

Controller: 11 minutes.

Narrator: The fact that Cougar 91 went down so quickly

supports Cunningham's hunch

that there was an oil leak in the main gearbox.

But it doesn't explain why the pilots thought

they could still reach land.

Cunningham: So something convinced him

that he could make it back.

Narrator: Looking for answers,

Cunningham asks the senior pilot at Cougar Helicopters

if anything stood out from his radio exchange with the crew.

Cunningham: Anything at all you could tell me would be helpful.

Pilot: There's one thing That Bugs Me: the oil temperature.

Greenspun: If the oil pressure inside the gearbox is falling

and the oil is leaking out, the temperature would begin to rise,

because now the gears are grinding against each other

And generating a lot of heat.

Pilot: He said the oil temperature was normal.

Davis: The gearbox oil temperature is still normal.

I don't think we've lost all the oil in the system.

Pilot: He thought he still had oil.

Narrator: The crew thought they could make it back to land

because the oil temperature read normal.

So was the oil pressure warning a false alarm?

Cunningham: When the crew mentioned the oil temperature

and it was indicating normally,

this told us that we needed to make sure

that what they were seeing was in fact accurate

to what was going on with the helicopter.

Narrator: Only the wreckage can provide the answers.

Five days of calm seas make the helicopter's quick recovery

from the ocean floor possible.

Chaulk: Over by the cabin floor.

Narrator: The team finally gets a first look at the wreckage.

What can it reveal about the deadly crash?

Chaulk: When you look at an aircraft that strikes land,

You have a wreckage trail.

You have ground scars that can tell you certain things.

The water gives up very little.

There's nothing left to look at.

It's just the surface of the water.

So you have to focus on the fuselage.

Cunningham: Damn.

So it was upright when it hit.

Chaulk: Pancaked.

Dropped like a rock.

My initial impression of the helicopter

was that it struck the water at a significant vertical rate.

When an object hits water, water is non-compressible.

It'll cause a little bit of a different kind

of damage signature than what would be as if it hit the land.

Cunningham: It's hard to believe anyone survived.

Narrator: Investigator Allan Chaulk's recovery

of Cougar 91 provides a big break in the investigation.

Chaulk: Here you go.

Cunningham: What have we got here?

Chaulk: Voice recorder transcript and audio file.

Cunningham: All the flight data on here?

Chaulk: Yeah.

Cunningham: Okay, good.

Chaulk: A major piece in any investigation is the recorders.

You start narrowing the focus down in each component.

Narrator: Will the data confirm an oil pressure problem

in the main gearbox?

Chaulk: Look at this.

Here's the oil pressure warning.

Here's the oil supply.

Gone.

Narrator: The flight data recorder shows

the main gearbox oil pressure dropped from 54 psi to zero

in less than two minutes.

Cunningham: That happened fast.

If the gearbox had lost all oil pressure,

the possibility of a catastrophic failure

of the gearbox had to be taken into consideration.

Uh-huh.

Narrator: Within days of the wreckage recovery,

the helicopter's manufacturer, Sikorsky,

has questions about the crash.

Cunningham: That's right, the whole main gearbox.

[Whispers] Sikorsky.

Alright. Yeah, good.

Yeah, we'll be expecting you.

Great.

Chaulk: They're coming?

Cunningham: Yeah, and the FAA.

They want to take a look at the whole main gearbox.

Narrator: It turns out Sikorsky

and the U.S. Federal Aviation Administration, or FAA,

are extremely interested

in the same piece of wreckage as Cunningham.

Cunningham: This way. Come over here and...

When the FAA and Sikorsky showed up,

it seemed they were very anxious about this accident.

Man: We need to look at this.

Cunningham: They unrolled the schematic of the main gearbox

And said that this is something that we have to look closely at.

This isn't the first time this has happened, is it?

Narrator: Investigators learn that eight months earlier

a Sikorsky S-92 in Australia got the same gearbox warning.

Automation: Gearbox pressure. Gearbox pressure.

Narrator: But that S-92 reached land in less than seven minutes

without incident.

The circumstances are identical.

Man: Catastrophic loss of oil,

unusual oil temperature reading; same.

Cunningham: We were conscious about

not jumping to conclusions too early.

That being said, if it was indeed the same problem

that was encountered in Australia,

it was gonna be important to take action quickly.

Narrator: Is there some flaw in the design of the main gearbox?

Cunningham: So what went wrong?

Man: Right here. The oil filter bowl.

Narrator: The oil filter bowl filters the 11 gallons of oil

circulating through the main gearbox.

It's fastened to the gearbox with three studs.

The investigators now focus on this key component.

Chaulk: Here we go.

Cunningham: Wow, two of the studs are gone.

Chaulk: It was very obvious once we pulled back the panels

that surround the main gearbox

that two attachment points had definitely been compromised.

There was a gap between the oil filter housing

and the main gearbox.

And that's where the oil in the main gearbox exited.

So it wasn't a slow leak.

It poured out all at once.

Narrator: This discovery confirms what investigators saw

in the FDR data: an extremely sudden loss of oil.

They now have concrete evidence that oil leaked

because of the broken studs.

Chaulk: So what made the studs fail?

Cunningham: What is it made out of?

Man: These ones? Titanium.

Chaulk: Hmm.

This looks like galling.

Narrator: Galling is a form of wear

caused when two surfaces are moving against each other,

particularly two different metals under pressure.

Titanium is prone to galling,

especially when in contact with steel.

Cunningham: When you're trying to tighten a nut onto a stud

that has a significant amount of galling,

it can actually jam before it's properly tightened

in the location it should be in.

Chaulk: Once fatigue cracking began,

well, it's just a matter of time until failure.

Narrator: Sikorsky studied

the Australian helicopter's broken studs

and concluded the galling was caused

by the steel nuts used to fasten them.

Cunningham: Here, take a look at this.

Chaulk: Alert to operators of the S-92.

Replace all titanium studs within a year,

or 1,200 flying hours.

Narrator: Six weeks before the Newfoundland crash,

Sikorsky issued an advisory

to swap the titanium studs for steel studs.

Cunningham: They knew the studs could fail.

Sikorsky had known there was a problem

with these studs previously.

The thing that we found distressing

was that most of these studs

showed some kind of damage on them,

which this enhanced visual inspection

should have picked up.

Sikorsky said that the titanium studs

would last at least a year.

Cougar got the replacement parts,

but maintenance didn't think that it was urgent enough

to replace the studs immediately.

When the accident occurred,

those parts had, had just been recently received by the company

and they knew they had to replace these studs eventually

with new steel ones.

Narrator: The question now is

why did Cougar delay replacing the studs?

[Rattling]

Davis: Ah, hell!

Dispatch, we're ditching.

Narrator: Investigators need to find out why Sikorsky

told operators they could wait a year to replace the studs.

Chaulk: No luck here.

Narrator: The team examines how the S-92's main gearbox

was certified.

Cunningham: Alright, I got something.

Sikorsky says possible failures of the main gearbox

that could result in a rapid loss of oil

are extremely remote.

Chaulk: Extremely remote. Cunningham: Yeah.

Chaulk: What does that mean?

Cunningham: One in ten million.

Chaulk: Two failures in less than a year.

That's not one in ten million.

Cunningham: Basically what they're saying

Is in the normal lifetime of this machine,

the possibility of a total loss of lubricant

will almost never happen.

Narrator: Sikorsky didn't communicate the urgency

of replacing the studs because they didn't understand

how severe the situation really was.

As the 17 victims of the crash are laid to rest,

the offshore oil community focuses

on the Cougar 91 investigation.

Man: We see this, this accident

as something that we're all in together.

Uh, we're hurting.

Narrator: Thousands of people from tourists to world leaders

fly in Sikorsky helicopters every day.

Are they at risk from some unknown flaw?

Investigators are eager for the medical examiner's report.

They hope it will tell them exactly what happened

to those on board the helicopter when it hit the water.

In the meantime, the team reviews the recordings

from the helicopter's cockpit voice recorder,

Hoping to find out

how the pilots handled the emergency situation.

Cunningham: Alright, this is at 09:45 local.

Davis: Dispatch, Cougar 91.

We're coming back to St. John's.

Greenspun: One of the first things that this crew did

was make a 180-degree turn back towards the land,

because it's always much better to make an emergency landing

on the ground than in the water.

Davis: Main gearbox failure.

We should be getting smells, vibrations.

I don't smell anything.

Greenspun: They're not feeling any vibration.

They're not smelling anything burning.

It's perfectly understandable that they would want to try

to get back to that parking lot at Cape Spear.

Lanouette: The problem could be with the sensor.

Narrator: As the team continues listening,

they hear the pilots troubleshooting the crisis.

Controller: Cougar 91, Gander.

You are unable to maintain altitude.

Is that correct?

Davis: In this condition, we have to be down as close

to the surface as possible in case of a catastrophic failure.

Greenspun: For a crew cruising at 9,000 feet in level flight

on a nice day,

the first task when a warning light goes on

is to try to figure out: Is it an indication system problem

or is there some kind of real underlying problem?

Cunningham: The captain reduces altitude from 9,000 feet

to 1,000 feet.

Narrator: The CVR then reveals something changed

just under 1,000 feet

that forced the pilots to suddenly ditch.

[Rattling]

Davis: Ah, hell!

Dispatch, we're ditching.

Lanouette: Ditching!

Ditching! Ditching! Ditching!

Narrator: Investigators need to find out what that was.

Cunningham: Let's look at the pinion.

Narrator: The pinion is the gear that transmits power

from the main gearbox to the tail rotor.

Chaulk: This tail rotor takeoff pinion

is being driven at a high rate.

And as heat builds up

the hardness of the material goes away,

now you have the potential for damage on the teeth.

Cunningham: Here you go.

So what is it supposed to look like? HMM?

Chaulk: Basically there were no teeth left

on that takeoff pinion in the end.

Narrator: Without oil in the main gearbox,

friction wears away the pinion's teeth.

Chaulk: It's stripped clean.

Well, no pinion, no tail rotor.

Cunningham: No tail rotor, no control.

Narrator: The tail rotor's main job

is to keep the helicopter straight.

It counters the spinning force created by the large rotor

That lifts the aircraft.

Without a tail rotor,

the helicopter would spin uncontrollably.

Greenspun: The pilot's only option at that point

is to land the helicopter with no engine power.

Narrator: When the engines are turned off,

air flowing upwards through the blades should allow

for the helicopter to glide to a safe landing.

Greenspun: The pilot still has control

over the helicopter's overall airspeed and direction.

Narrator: The optimal altitude for such a glide is 200 feet.

But the Cougar captain kept his altitude at nearly 1,000 feet.

Cunningham: Why didn't he take it down lower?

Chaulk: There's a 500-foot hill between him and the airport.

He was trying to stay high enough to clear it.

Way too high.

Lanouette: Alright, we're turning.

Davis: Call it in.

Lanouette: We're getting prepared to, uh, ditch.

Uh, ditching!

Tadros: He was at high airspeed

and at 800 feet and at high power.

And that aircraft really was not in a position to be ditched

in that configuration.

That was in no way a ditching that day.

That was a crash.

Narrator: Investigators of the Cougar 91 crash

look into the final communications

between the captain and first officer.

Cunningham: Okay, so the checklist says land immediately.

And we know that's not what they did.

Chaulk: F.O. says, "Checklist is complete.

We're in a land-immediately condition."

Greenspun: Land immediately means put the helicopter down,

even if you're over water, or not very flat terrain.

Cunningham: But the captain says...

Chaulk: I'm going to stop descent at 1,000 feet.

Cunningham: The first officer is telling him

that they should put it down in the water.

Chaulk: Well, that's easier said than done.

Lanouette: We're in a land-immediately condition.

Davis: Roger, I am going to stop descent at 1,000 feet.

Lanouette: 1,000 feet, okay.

Checklist is complete.

We're in a land-immediately condition.

Tadros: I would say that there really was a disconnect

in that cockpit.

The captain had a very strong personality,

and as the situation developed

he became more and more intent upon making it to land.

Davis: I'm going for the nearest piece of terra firma

I can get to, whatever I see first,

if it's Cape Spear or a parking lot.

Tadros: The first officer had more experience

in over-water flying and ditching scenarios.

He used to fly the Sea Kings for the Canadian military.

But he had a quieter personality.

Cunningham: There should have been more interaction

between the captain and the first officer.

Despite the concerns that the first officer

was trying to convey to him

about the need to possibly land immediately,

when he didn't hear any noises or sounds,

he made a decision that he wanted to make,

and that's called confirmation bias.

He wanted to make it back to shore.

Chaulk: At 09:48:32, the captain says,

"You know, I'm thinking this is a sensor problem."

Why does he think that?

Cunningham: And they said that the oil temperature was normal.

But with a leak it should be spiking.

They believed that they had probably an oil pump

or oil pressure sensor problem

because their oil temperature gauge had not increased at all.

It was basically showing what would be expected normally.

Chaulk: No, the oil's reading is normal range.

Narrator: A sensor in the main gearbox

provides an oil temperature reading for the crew.

Cunningham: You know, all the oil is gone by now.

It's reading the air temp. It's reading the air temp.

Chaulk: The oil temperature sensor in the main gearbox

of the S-92 is a wet sensor.

If there's no oil present, it's just sensing

the ambient temperature within that gearbox.

They felt no strange vibrations.

Cunningham: No.

Chaulk: No smell.

And they saw the temperature was normal.

Cunningham: Yeah, that makes sense.

That's why the guy kept flying.

Chaulk: They had no idea how much trouble they were in

until the pinion failed.

[Rattling]

Davis: Ah, hell.

Dispatch, we're ditching.

Lanouette: Ditching.

Airspeed 122, Matt.

Narrator: But the tail rotor fails just below 1,000 feet,

too high to perform a safe ditching.

Cunningham: They lost directional control

of the helicopter.

And this is probably the most challenging emergency

that any helicopter pilot will face.

Greenspun: With no engine power, descent rate is, you know,

usually about 1,500 feet per minute,

so in the best of circumstances

this crew only had about 30 seconds to do everything right.

Narrator: Is there anything the pilots could have done

in those last few seconds to recover?

Cunningham: So they lost the tail rotor here.

And it was all over in less than 15 seconds.

Davis: God! The engines! Shut 'em down.

Shut 'em both down!

Lanouette: Shutting down one and two.

Okay, nose up, nose up.

Alright, we're turning.

Davis: Call it in!

Lanouette: We're getting prepared to, uh, ditch.

Uh, ditching!

Ditching! Ditching!

500 feet.

You got this.

Get it pointed downwind.

Davis: It's turning right on me.

Come on!

Lanouette: There you go. You got this, you got this,

You got this.

Davis: I'm full up!

Lanouette: Doing good. Keep her spinning.

Rotor's low.

Narrator: It's too late.

The fate of Cougar 91 is sealed.

Davis: Ah, here we go, here we go!

Lanouette: Brace!

Greenspun: The ditching began from 800 feet,

so those control inputs were all initiated too high.

So the result was essentially sinking like a rock.

Cunningham: The captain, in the end

he unfortunately wound up in a position

where he didn't have enough energy remaining

To land safely on the water.

Narrator: The main gearbox makes helicopters top-heavy.

Once they hit water, they tend to capsize and sink quickly.

Chaulk: The aircraft did strike the water

with a high vertical descent.

And it would not have been on the surface of that water

for very long at all.

Narrator: Were the passengers doomed

once Cougar 91 hit the water?

Investigators finally get the medical examiner's report.

Cunningham: Allan, you're not gonna believe this.

Narrator: The conclusion is shocking.

Chaulk: They all survived the crash.

Narrator: Instead, all 17 victims died from drowning.

Cunningham: It was a bit of a shock

to think that 17 people had survived that impact

but only one had survived the accident.

Narrator: So why does only Robert Decker survive?

How was he able to escape?

Investigators start by looking at where he's seated.

Cunningham: So Decker is seated in 3D, on the right-hand side.

Narrator: The team has already determined that as Cougar 91

hit the surface, it rolled left, and quickly filled with water.

Chaulk: Decker was lucky to be on the right side.

Cunningham: Undo harness, find a window,

get out, get up to the surface.

That's if you're not too badly injured.

But look at this.

I mean, look at it!

Somehow he gets out

in a helicopter that is sinking past 30 feet.

He holds his breath, he gets to the surface,

all in water that is just barely above freezing.

Even with a survival suit on,

as soon as you get immersed in that cold water,

that cold water is going to rob

your ability to hold your breath.

Chaulk: And he floats there for an hour and 20 minutes

before he's rescued.

Cunningham: That man is lucky to be alive.

Narrator: A helicopter with a design flaw.

Automation: Gearbox pressure. Gearbox pressure.

Narrator: Instruments with a misleading readout.

Lanouette: Your temperature looks normal.

Narrator: And a cockpit with differing assessments.

Lanouette: We're in a land-immediately condition.

Brace! Brace!

Narrator: Only one person survived the resulting crash.

What did Robert Decker do to ensure his survival?

Chaulk: It's very important to analyze how individuals

would have gotten out,

and how the individuals that didn't get out,

what affected their ability to exit the aircraft?

Narrator: Investigators hope the lone survivor

can provide some answers.

Eight months after the crash of Cougar 91,

Decker testifies at a hearing in St. John's, Newfoundland.

Decker: The helicopter was sinking quickly

with its port side down, and it instantly filled with water.

It was as if it was sinking

The same way it was dropping through the sky.

I undid my seatbelt

and I pulled myself out through the window.

The window would have been directly above me

because, um, as it was sinking on its side.

Cunningham: When he first became conscious of where he was

and the environment he was in,

he looked up and he could see a light in the distance.

And because the fuselage was already opened up,

he was able to get out.

Decker: Then it was a long, I guess, ascent to the surface.

I kind of had my hands above my, my head.

And, uh, I could look up and I could see

it was getting brighter and brighter,

and I guess eventually my arms broke the surface

and I could tell that I survived the helicopter crash.

Cunningham: He said that he attributed some of it

to luck as well as his physical abilities.

Narrator: A crash into water is traumatic.

Most passengers will be stunned and unable to act quickly.

Research shows that as many as 15 percent of passengers

fail to take any action.

In fact, drowning is the leading cause of death

following a helicopter ditching or a crash into water.

Cunningham: With the water temperatures we had,

even with a survival suit on, as soon as you get immersed,

that cold water is going to rob

your ability to hold your breath.

Narrator: That's why survival training is a critical rehearsal

for such an event.

When investigators dig into the training

of all the people on board Cougar 91,

they discover that everyone had received

mandatory survival training in a simulated ditching.

Decker: If the helicopter sinks,

you have to wait till it's fully submerged,

and then you kind of take your last breath

and you release your seatbelt.

Your hand is already on the ledge,

and you pull yourself up.

Narrator: But Decker was the only passenger

who had cold water experience.

In his youth, he sailed often in the Atlantic

and had capsized in the cold sea.

Decker: When the helicopter suddenly filled with icy water,

I could react instinctively.

It was like a reflex to take a breath and to hold it

and just stay calm until I could get to the surface.

Narrator: While Decker's training

and cold water experience played a key role in his survival,

safety on board a helicopter begins long before it lifts off.

Decker: The only way to keep every offshore worker safe

is to keep every helicopter in the air.

Narrator: In its final report,

the Transportation Safety Board makes recommendations

that will improve safety

not just in the Sikorsky but in all helicopters.

Emergency underwater breathing apparatus are now mandatory

for all occupants of helicopters involved in overwater flights.

The unit provides approximately two minutes of air.

Cunningham: This was another key change that took place

as a result of this accident,

and again, not just in Canada but around the world.

Narrator: The TSB also recommends reviewing

how long a helicopter should be able to run

without any oil in the main gearbox.

Tadros: It was a broad and deep investigation

that uncovered every safety issue that there was to uncover

about that helicopter and about flying in the offshore.

I think our recommendations made flying in the offshore

much, much safer.