Original subtitles

New South Wales, Australia, 2020.

After dropping a load of fire retardant... Load us away.

...firefighters on the ground witness the unthinkable.

A C-130 fire bomber crashes, killing all three crew members.

It's a guttural, visceral loss.

Investigators must determine the cause of the crash within an active fire zone.

Look at that. Complete destruction.

And they must do it without a flight data recorder or a cockpit voice

recorder. This is a lot of important data that we did not have access to.

But fellow pilots do provide valuable insight.

I didn't think it was safe.

I rejected the task.

Why was the fire bomber even out there?

Whoa, hang on.

Colson Aviation B137 is circling above a wildfire near Adaminaby, Australia.

2,000 feet. Copy, 2,000 feet. Let's make another turn and see what we can see.

Colson Aviation is one of the world's leading aerial firefighting companies.

Headquartered in British Columbia, Canada, They operate a fleet of fixed

and rotary wing firefighting aircraft around the world.

The majority of aerial firefighters are private companies, and they are

contracted by the government.

Visibility is still pretty bad, and I think we're going to need a closer look.

Yeah, I'm going to take her down to 1,000 feet.

The crew of the 737 is searching for somewhere to drop 4,000 gallons of fire

retardant. Descending to 1,000 feet.

So they're looking for that sweet spot. They're looking for the perfect drop

altitude with the perfect line to be able to drop that retardant right where

the firefighter needs it.

The 737's mission is just one battle in a much bigger war.

The Black Summer fires were some of the worst that Australia has seen.

New South Wales was the hardest hit state. They suffered a loss of 21% of

its alpine vegetation.

which encompassed over 68,000 acres of burned area.

It challenged everybody in the fire services, in aerial firefighting, in

ways that they've never been challenged before.

Air crews from the United States and around the world respond to the call for

help and join their Australian counterparts to battle the wildfires.

As the crew prepares, they get as low as they can to make a drop.

Descending to 800 feet.

800 feet.

Got wind shear.

There's been a rapid change in wind speed and direction.

Affirmative. Increasing thrust.

Climbing.

In aerial firefighting, you've got to get very low and very slow, and at times

you'll all of a sudden get hit by a gust that you weren't expecting.

All right, I think we got her back under control.

Aerial firefighting pilots face unique challenges compared to your average

everyday pilot.

That's why they are so experienced and so skilled in what they do.

All right, can you get us direct to base?

After almost 30 minutes of difficult flying in dangerous conditions, the crew

decides not to return to the fire in Adaminaby.

Heading set for return to Richmond Air Base.

Autopilot on.

You know what, though? We need to contact fire control and the bird dog.

Everybody needs to know that conditions out there are deteriorating rapidly.

Agreed. 100%.

The crew sends out a warning about the conditions to the control center and

their lead plane.

There's often what's called a bird dog or a lead plane, which is a much smaller

aircraft, more nimble, a very experienced pilot who can better assess

the drop for the tanker pilot before the tanker pilot even arrives.

Do you hear that?

B-134.

The pilots of the 737 overhear another Colson aircraft headed to the fire zone

they just abandoned.

B-134, this is B-137. Do you read?

Colson B-134, a modified Hercules C-130 with a crew of three, is approaching the

fire in Adaminaby.

Good afternoon, B-137.

B-134, reading you loud and clear.

The pilot in command is 45-year-old Ian Macbeth.

He's flown nearly 1,000 firefighting missions like this one.

We just did a drop in Adamina B.

Conditions are very bad.

We had some crazy wind, and visibility is really poor.

You can go take a look, but I'm not going back there.

Copy that, B-137. We'll assess conditions carefully.

Thanks for the warning.

Communications in aerial firefighting is an integral part of the overall

firefight for weather conditions and changes on the fire ground.

The C-130 co-pilot is 42-year-old Paul Hudson, a former U.S. Marine pilot.

43-year-old flight engineer Rick De Morgan is on leave from active duty in

the United States Air Force.

If you were to put together the perfect crew for the type of thing that 134 was

fighting, You would get these guys, or somebody exactly like them.

Now approaching the target area in Adaminibi, the crew descends to 2,500

feet and begins a circuit pattern.

Oh, boy.

There's that chop B-137 I was talking about.

No doubt this wind will be pushing the smoke all over the fire ground.

Visibility is terrible.

Another day at the office, right, fellas?

Yeah.

Well, let's take her down to 2,000 feet, get a closer look.

Despite the other crew's warnings, Macbeth wants to assess conditions for

himself.

Aerial firefighters are a unique breed in that they're highly experienced

pilots before they ever get behind the controls of an aerial firefighting

aircraft. They're already people who conduct risk assessments.

They're people that know how to handle a...

Crisis situation.

Coming around for one more circuit.

Though the conditions seem dire, a C-130 fire bomber like B-134 is modified

for such extreme conditions.

The C-130 is an amazing aircraft.

It's a robust, strong airplane that was built to haul and deliver a lot of cargo

and a lot of weight. They make wonderful air tankers.

C-130 air tankers are retrofitted with structural reinforcements in their

fuselage to accommodate tanks that carry more than 16 tons of fire retardant.

Having four big engines on a C-130 like that, it is wonderful to be able to

power out of something if you find yourself in a position to be in trouble.

But no aircraft is invulnerable, and for professional flight crews, safety is a

priority.

That 737 crew was dead right.

These winds are too crazy.

All right, I'm calling this one off on North High Fire Control.

Kuma FCC, Coulson B134.

Go ahead, Coulson B134.

Kuma FCC, conditions at Adam Enemy, too smoky and windy.

There's no way to make a drop here.

Copy that, Coulson B134.

The Fire Control Centre in Kuma, Australia, serves as a local base for

the New South Wales Rural Fire Service.

It coordinates firefighting efforts in the area, both on the ground and in the

air.

B134, we're sending through coordinates for an alternative target at peak view.

Stand by.

Your new heading is 085.

Copy that, Kuma FCC, 085, proceeding to peak view.

The C-130 is directed to another fire.

New heading is set.

All right, plan B.

Here we go.

When you've got a crew assessing the situation and saying, is it a little bit

too windy, it's a little bit too smoky, let's not drop here.

It's a good thing to have the ability to go on to another location.

The C-130 is rerouted to an area 58 kilometres to the east of Adaminibi,

known as Peak View.

A remote area of hills and farmland running up to a mountain ridge.

All right, let's see what we got here.

There, along that ridge line.

If we aim for the east side. I see it. Yeah, that could work.

Let's get a closer look.

Starting first circuit now.

Following standard procedure, the C-130 flies several low-altitude circuits over

the fire ground.

There's a multitude of factors that air tanker pilots look at when they go into

a fire.

We're talking about the fire behavior.

We're talking about the weather.

What are my escape routes like?

All right, that's three circuits.

I'd say we're good to drop just east of that ridge there.

Agreed? Yes, sir. Good to go.

Stand by.

Descending towards drop area.

Now all that's needed is for the C-130 to get in close enough to make a

successful drop.

The crew of bomber 134 prepares to drop a load of fire retardant on a wildfire

near Peak View, Australia.

Okay, there's our line.

Release point in sight.

Rolling in on final.

Passing through 400 feet.

300.

Standby to drop.

Hang on, almost there.

Probably the most critical time in this whole process is on the drop because

you're losing a lot of weight on the airplane, which means the aerodynamics

of the airplane are going to be different. You're going to need to climb

fast.

We are at 200 feet.

Clear to drop.

Dropping, dropping. Load us away.

As soon as the C-130 drops its load of fire retardant... Clamp thrust flaps 50.

Flaps 50.

The crew tries to regain altitude.

Whoa, hang on.

Come on.

Still not gaining altitude.

But the plane won't climb.

Bomber 134 has crashed into the Australian bush.

Tragically, there appears to be no survivors as a result of the crash.

The aerial firefighter community is very small, and it's a guttural, visceral

loss.

We could just have a minute's silence.

When I got the call, bomber 134 had crashed near Cooma, New South Wales.

Hercules, the C-130, is a very reliable aeroplane and I honestly couldn't

believe it.

So how far is the crash site from Cooma?

The Australian Transport Safety Bureau, or ATSB, is alerted to the disaster

immediately.

About 35 miles northeast, near Peak View.

Oh, I know that area. That's pretty remote.

Surrounded by brush fires. We have a few teams dispatched to the area.

It was located on a single-direction access road that was impacted by fire a

number of times during our on-site activities.

So, the fire bomber is a modified C-130.

What do we know about its history?

While investigators wait for updates from the crash site... They look into

the plane's history for anything that could explain the crash.

Alright, here's the certificate of airworthiness.

Looks like everything's in accordance with FAA standard.

And according to the aircraft specs, it was converted to fire bomber in 2018.

Since then it's accrued 683 hours of firefighting operations.

And it had an inspection just yesterday.

Any issues?

Nothing significant.

A review of the aircraft's maintenance log books and worksheets showed that

there was no pre-existing defects prior to the flight departing, so we were now

looking at something happening during the flight that we had to consider.

Investigators continue to sift through the aircraft's records.

Take a look at this.

The C-130 was equipped with a cockpit voice recorder, but no flight data

recorder. Nor was it required to have one.

Really?

Well, that makes it more challenging.

Where aircraft are fitted with a flight data recorder, this gives investigators

a huge amount of information that can be used to determine aircraft performance.

This is a lot of important data that we did not have access to.

Thank you.

Footage from the New South Wales Police gives investigators a bird's eye view of

the severity of the crash.

Look at that.

The scale of devastation was incredible to see. It was a shocking sight.

All that was recognisable while approaching was that tail and the aft

section. Everything forward of the back of the wing was in multiple pieces

throughout the site.

So the first point of impact is here, clip the tree, then the wreckage extends

all the way up to here.

Investigators discover that after impact, the wreckage slid 600 feet

uphill.

Must have come in pretty steep for that kind of damage.

It was evident that the aircraft had come in quite heavy. We're talking a lot

of energy here.

So what could have caused the devastating crash?

Investigating an accident like this, we start to sort of think about what could

possibly have gone wrong.

Are we looking at an engineering issue here? Are we looking at an operational

issue here? Or are we looking even at an environmental issue?

With that level of devastation we have to consider a structural problem.

Agreed.

Did the Colson C-130 experience a structural failure prior to crashing

violently into the ground?

One of the fundamental things we have to determine is all the aircraft on the

site. So the cockpit was torn away and the nose is here.

We have to locate effectively the four corners of the aircraft to determine

that all the components of the C-130 were on site.

There's evidence of the left wing tip and the right

and of course the tail.

It's all there.

The C-130 did not suffer any kind of structural failure prior to impact.

If there had have been an in-flight breakup, there would have been pieces of

the aircraft that weren't in the wreckage site.

They would have been further back along the flight path.

Look at this.

We've got retardant at the site.

So they only released a partial load, which means they were carrying extra

weight.

Typically, the flight crew are trained if they do run into any emergency

situation to dump that retardant. This would increase the aircraft's

performance.

Why didn't the crew release its remaining fire retardant? It could be a

factor if they were struggling to regain altitude.

Whoa, hang on.

Come on.

Still not gaining altitude.

We've got something.

Several days after the crash of the Colson fire bomber, the investigation

receives unexpected evidence.

Eyewitness video from the RFS.

A firefighter with the RFS, or Rural Fire Service, captured the final seconds

of the C-130 on video.

We were provided with a witness video which had captured the last 25 seconds

of the aircraft's flight.

You see it coming in low.

It drops the fire retardant.

And it looks like it starts to climb.

Right.

And for some reason, it doesn't regain altitude.

All of a sudden... The

witness videos

essentially provided an unedited version of the aircraft's final movement.

A short time after the retardant dropped, the aircraft became obscured by

smoke.

I think there's more we can do with this video.

Typically, when we receive a witness video, we're able to use basic

photogrammetry on determining the aircraft attitude.

In this case, we're using new software that we had just got access to.

Will video analysis software provide investigators with more information

about how and why the Colson fire bomber crashed?

The use of the 3D tracking software allowed us to look at the witness video

in a lot more detail.

We could look at the aircraft's attitude. We could look at the pitch and

roll angles to get a better sense of what was happening.

OK, that's everything.

At the beginning of the drop, the pitch is level with a slight left bank.

Seems pretty normal.

After the drop, the plane is banked left and pitched up.

They're climbing out.

For 10 seconds following the drop, we could see that the aircraft had

established a positive rate of climb up to about 170 feet above the drop height.

And through the remaining images, the plane appears to be sinking.

Looks like a stall.

All the signs are there.

The witness video showed that the aircraft's final movements were

consistent with an aerodynamic stall in terms of the aircraft stopped climbing

and the rolling movement of the aircraft.

However, without a flight data recorder, we were unable to confirm with a degree

of certainty that the aircraft had stalled.

The question is, did it stall?

And if so...

Why?

Will the wreckage of the Colson C-130 support the ATSB's theory that the fire

bomber stalled?

Excellent. Cockpit voice recorder.

Let's get that to HQ for download straight away.

Finding the cockpit voice recorder gave us an opportunity to understand the

crew's communications within the cockpit.

While data from the cockpit voice recorder, or CVR, is processed,

investigators examine the engines.

Thanks for coming in.

An expert from the engine manufacturer, Rolls-Royce, assists with the

examination.

Were the engines operating?

Were they operating comparably across all four of them? And is an engine

failure why this aircraft stopped flying?

As you can see, there's pretty heavy impact and fire damage.

Let's have a look.

Have a look at that.

The compressor blades are badly damaged.

That looks like molten metal.

All signs of engine ingestion.

There was a significant explosion and fireball when this aircraft impacted the

ground. The evidence of molten metal inside the compressor casing was

indicative that the engines were operating when this fireball occurred.

The engines had ingested the fire and the broken bits of metal.

Just got confirmation from our records team the flaps were at 50.

That's the right configuration for climb out.

So we've ruled out engine failure and improper configuration as causes for a

stall.

Normally we would have airspeed and engine parameter data from the flight

data recorder, but because we didn't we had to come up with different ways to

determine if the aircraft aerodynamically stalled.

Let's look at the CVR transcript.

Will it explain what could have caused the C-130 to stall?

Training exercise, what is this?

This is not our flight.

Looks like it's from a previous flight in California.

Nine months prior to the accident flight, the inertia switch had activated

during a hard landing.

This meant that the recording device stopped recording any further

information.

With no CVR or FDR available, investigators turn to what data they do

have. Okay, according to the equipment list, the C-130 was equipped with two

tracking devices, the ADS-B and SkyTrak.

ADS-B and SkyTrak are two onboard positioning systems that transmit the

plane's location and other data to satellites and ground stations in real

time.

At the very least, that'll give us a flight path.

Perhaps more evidence of a stall.

We had to look at alternative ways to start looking at the aircraft

performance. This included other real-time tracking data that was

available to us.

We've got the data.

So they approach the area at 2,000 feet.

They complete their first circuit at 1,500 feet.

Second circuit at 500 feet.

Final circuit, 1,000 feet.

We're doing a proper survey of the situation.

This is really to assess the weather conditions at that lower level.

OK, so what about the drop itself?

Before they drop into the higher-risk 200-foot altitude.

They make the drop at 200 feet and then they climb up to 370.

And they're at a very low altitude, three seconds later.

What airspeed would the plane have to be flying in order to stall if it was in a

climb-out configuration?

While the tracking data further supports the enhanced witness video, can it

reveal if the plane was flying so slowly that it stalled?

An airplane has a specific stall speed for specific configurations, flaps up,

flaps down, and particular weight.

That's flaps 50, weight 131,000 pounds after a partial retardant drop.

Investigators start by calculating the stall speed of a C-130 on climb out.

We'll need to factor in some turbulence near the drop area.

Turbulence introduces the possibility that you're going to have a sudden

updraft or a sudden downdraft, and it's going to affect your altitude and your

attitude.

All right, let's start with moderate turbulence with a load factor from 0.5

Gs to 0.99 Gs.

They factor in different levels of turbulence likely present at the time of

the incident.

And severe turbulence up to 1.99 Gs.

The higher the turbulence, the higher your airspeed needs to be to ensure that

you don't stall.

Alright, that should do it.

So in moderate turbulence, the C-130 stall speed is between 101 and 117

knots.

In severe turbulence, it's between 117 and 143 knots.

Was the C130 flying at a stall speed between 101 and 143 knots,

causing it to plummet to the ground?

Pull up the ground speed from the tracking data.

To determine if the C130 was flying at stall speed, investigators examined the

ground speed recorded in the tracking data.

We didn't have the airspeed.

and therefore had to estimate it based on ground speeds that had been recorded.

Ground speed for the C-130 is 144 knots before they dropped the retardant,

increasing to 151 knots before impact.

Alright, now let's factor in the wind speed.

We knew that they were flying in hazardous environmental conditions,

which included gusting and changing wind conditions, and this then posed a

challenge for us.

to determine what the airspeed was.

Airspeed measures a plane's speed relative to the air it's flying through.

That's the weather at peak view, less than a mile from the crash site.

We've got a lot of turbulence with winds gusting from the northwest.

15, 30, and 40 knots.

Pull up the aerial image from the crash site.

What direction was the C-130 flying?

Right after the drop, the C-130 was flying south-southeast.

With winds from the northwest, that would mean they would have had a

tailwind.

Tailwind as high as 40 knots?

That's extreme.

Sounds like wind shear.

Wind shear is a sudden change in the wind's direction or speed.

resulting in drastic changes to a plane's airspeed.

At low altitudes, it can be deadly.

If you have a sudden tailwind, that's going to rob you of airspeed, and you

may have a struggle staying in the air.

All right, we've got the wind speed, now let's calculate the airspeed.

To calculate the C-130's airspeed, investigators also factor in other

weather data on the day.

Temperature, atmospheric pressure.

The airspeed was between 100 and 123 knots in the last 20 seconds of flight.

There it is. The C-130's airspeed falls within its stall speed in those

conditions.

The team concludes the plane was hit by wind shear.

Whoa, hang on.

That resulted in a sudden increase in tailwind.

Still not gaining altitude.

Which robbed the plane of vital airspeed and caused it to stall.

Here's what's troubling.

Many planes experience wind shear events and don't crash.

So why the C-130?

Investigators examine Colson's onboard safety features to determine if their

pilots were equipped with a warning system that could have helped them

recover from wind shear events.

Looks like some of the Colson aircraft, like the 737, have an onboard wind shear

warning system.

We got wind shear.

Wind shear. Wind shear.

Wind shear. Affirmative.

Terrain, terrain.

Pull up.

Any time you can put something in the cockpit that is going to give you the

capability of identifying wind shear or the potential for wind shear, it is a

win.

Did the Colson C-130 Fire Bomber also have a wind shear warning system?

The C-130 did not have a wind shear warning system.

The C-130H model aircraft was built in the early 80s.

Whoa, hang on.

Colson believed that their highly experienced pilots would be better able

to identify wind shear than an onboard warning system.

Wind shear. Wind shear. They are trained to recognise the onset of wind shear

through the degradation of the aircraft performance.

Come on.

Come on.

A wind shear warning at a higher altitude would have allowed the crews to

immediately respond to the situation, but if such a warning occurred at a low

altitude, there may not have been sufficient time for the crew to recover.

We are at 200 feet.

Clear to drop.

Dropping, dropping. Load is away.

Investigators conclude that wind shear warning or not, at such a low

altitude... Whoa.

Hang on.

Come on.

With 25,000 pounds of fire retardant still on board... Still not gaining

altitude. The C-130 fire bomber was just too heavy.

If all the retardant had been dumped, it would have increased the aircraft's

performance. By about 50%. And lost too much airspeed from the extreme wind

shear event.

Wind shear.

Maximum thrust.

As a result of flying into a combination of wind shear and tailwind at low

altitude and a relatively slow speed, the aircraft performance decayed into

the stall region.

We're stalling.

Resulting in the aircraft colliding with terrain.

But understanding why the C-130 crashed doesn't entirely explain the accident.

Given the dangerous conditions, why was the fire bomber even out there?

As aerial firefighting is operating within a very dynamic environment, it's

important that any new information or changing information is communicated to

ensure that the safety of flight and the operation as a whole is maintained to a

high standard.

Investigators examined the vast communication network involved in

monitoring and dispatching firefighters the day the C-130 crashed.

Who knew what and when?

There is a large number of individuals at various different locations, all with

different information.

What were the pilots told about weather conditions in the drop zones?

There are three planes tasked to Adamina B on the day of the crash.

First, the 737 departs at 11.27am.

And what time did the C-130 depart?

It departed at 12.05pm.

And the bird dog's departure?

What is it?

At 12.04pm, virtually the same time the C-130 departed, the bird dog declined

the task.

We had learned through the investigation that the bird dog pilot assigned to Adam

Innaby had rejected that task.

But why?

Why did you reject the task?

Investigators speak to the bird dog pilot to understand why he refused the

assignment.

I was in the snowy mountains a couple weeks earlier.

There was heavy turbulence.

The bird dog pilot experienced a downdraft and an uncommanded 30 to 40

degree roll.

You were able to recover?

Barely. I had to execute an escape maneuver.

So, tell me about the day of the accident.

The forecast and the conditions were even worse.

I didn't think it was safe, and I rejected the task.

You told the Richmond Air Base manager.

Did you tell anyone else?

I thought they would inform the other aircraft.

The Bird Dog pilot expected that their decision not to fly and to reject the

task based on the weather would be communicated to other crews who were

going to operate in that same area.

The Richmond Air Base informed the State Air Desk that the Bird Dog rejected the

task. But did the State Air Desk tell other crews?

They didn't tell the 737 or the C-130.

What time did the 737 leave Annaminibi?

12.25pm.

Did they return to the area?

Doesn't look like it.

The conditions were really bad.

The pilot in command warned the bird dog of the conditions and that they wouldn't

be returning to the area.

That's not all. They also reported the situation to Kuma Fire Control.

Kuma, FCC, this is B-137.

Conditions in Adaminibi are dangerous.

Cancel all aircraft operating in the area.

They even radioed the Richmond Air Base.

Investigators learned the 737 made multiple efforts to advise others of the

dangers in Adaminibi.

Did anyone inform the C-130 of those messages?

Not the Richmond Air Base, not the State Air Desk.

No official body told the C-130 that conditions were worsening.

While there was a lot of information that was being shared with all the

flight crews on that particular day,

There were missed opportunities to provide the crew of Bomber 134 with a

lot more information about what was happening in this area.

Looks like the 737 overheard the C-130 on the approach frequency and reached

out to them.

We just did a drop.

Conditions are very bad. We had some crazy wind and visibility is really

poor. You can go take a look, but I'm not going back there.

Copy that, B-137. We'll assess conditions carefully.

Thanks for the warning.

Despite warnings about the conditions at Adaminaby proving to be correct... That

737 crew was dead right.

Kuma FCC, there's no way to make a drop here.

Copy that. The crew of B-134 was sent to a second location just ten minutes away,

at peak view.

Your new heading is 085.

Copy that, Kuma FCC, 085.

Even though it was the C-130 crew's decision, they didn't get a complete

picture of the risky conditions they were flying into.

If additional sources had warned the C-130 of the conditions in the area, the

crew may have rejected the task at peak view.

The ability of flight crews to make the most informed decision about the safety

of continuing these operations in a high risk environment.

relies on clear solid communication of all of the available information whether

that be from local crews and their activities or from task rejections based

on previous experience.

In the ATSB's final report they make many detailed recommendations including

fitting wind shear warning systems on all C-130 fire bombers.

Above all, the ATSB highlights the need for new procedures for making risk-based

decisions.

Aerial firefighting pilots are not reckless individuals. They're very smart

and methodical.

This is definitely a brotherhood of pilots.

And I believe that in aerial firefighting, when a pilot's lost, it's

not only felt by one person and their family, the families of the pilots, the

company.

but it's felt throughout the whole industry.