Original subtitles

One of the world's most sophisticated warplanes speeds down the runway at

Guam. Their mission that day was to return home.

But the takeoff ends in disaster.

A $2 billion stealth bomber goes up in flames.

We want to know what the heck just happened.

The entire fleet is grounded.

This could be the end of the B-2 bomber program.

Lane goes full nose up.

Investigators analyze the flight second by second.

What about this?

And discover a hidden vulnerability in the B-2's electronic armor.

There's no way a pilot would understand the system well enough to realize what

could happen. What is going on?

You're good to go, sir. Thank you.

and captain justin grieve are ending a four-month deployment in guam better

yeah it looks good okay let's head home then copy that

anderson air force base is both a training facility and a launching point

for u.s military operations in the western pacific

generator one is on

Engines ground idle, 25% confirmed.

Free flight checklist is complete.

Their mission that day was to return home.

Our time was up in Guam, and they were beginning a 16-hour continuous

flight back to Nob Nostra, Missouri, Whiteman Air Force Base, which was our

home base.

They're one of two crews returning home today in a unique warplane.

The B-2 bomber.

It was a flying wing design and really a marvel of engineering.

The Air Force ended up spending $44 billion to develop and then field the

fleet of B-2 bombers.

Developed in the 1980s during the Cold War, the stealth bomber was designed to

evade Soviet radar.

There are only 21 of them in existence.

It can sneak in with much less chance of being detected either by enemy surface

-to-air missile defenses or enemy fighters.

Tower, Death 5, startup is complete. You can activate our flight plan.

Refueling number one will be at ARCP Charlie at 0735 Zulu.

Expecting to unload 51,000 pounds.

Control point Charlie, copy.

Today, the 7,000-mile journey home from Guam will require the crew to refuel

near the Hawaiian Islands and then over California before reaching Whiteman Air

Force Base in Missouri.

Major Link is a qualified instructor on the B-2.

Captain Grieve is an experienced pilot with more than 2,500 hours of military

flying experience.

They are among only 300 pilots qualified to fly the B-2.

The aviators in the B-2 at that time were the absolute best of the best.

They were hand-picked.

They were vetted extensively.

They were truly an elite group of aviators.

Grieve and Link are second in line to take off.

The plane they're flying is named Spirit of Kansas.

Every B-2 bomber is named after an individual state, except for two.

There's a Spirit of America and a Spirit of Kitty Hawk.

That's six plus one, clear for takeoff.

Maintain 5,000.

Pitot heat is on.

Clear right.

Good to line up.

The pilots must carefully maneuver the massive 168-ton bomber to the foot of

the runway to ensure they don't put any dents in the B-2's shell.

We try to taxi slowly because you're a low observable platform.

So, obviously, if you were to scrape the airplane, you'd degrade the capability

of the warfighting machine.

Death 5, go Channel 5.

Death 5, copy, Channel 5.

Death 5, check 5.

Our lead is airborne. We go in 60.

On this flight, Captain Grieve is the mission commander.

What's different is the captain, like you would think the aircraft commander,

is actually in the right seat. And we call him a mission commander.

And the pilot is in the left seat.

Last time, CT.

Good cues.

The very first time I flew the V2, I felt like I was a bird.

It was so smooth.

You just slightly touch the flight controls and she does what you want.

100 knots.

Spirit of Kansas lifts off the runway at Guam.

Almost immediately, the massive bomber pitches up dramatically.

Next thing they know, they're going straight up.

The momentum of that maneuver up caused their pilots to experience about 1.6 Gs.

The aircraft's no longer doing what it's supposed to be doing.

Full power.

The B-2 isn't gaining altitude.

It's still only 80 feet off the ground and losing speed.

Make believe you're in your automobile right now. You turn left, but the car

turns right.

What is going on?

That's not the way it's supposed to work. That's the scenario these pilots

were in.

The pilots now feel their airplane shaking violently and realize it's on

the verge of stalling. From my 15 years of flying the B-2.

The only time I felt the B-2 shake is in the simulator.

That's the only scenario where you will feel that shake.

You never feel it otherwise.

The plane's left wing drops.

Grieve knows the plane is heading for the ground.

There's only one thing he can do to save his and Major Link's life.

They are trained to have that gut feel of when to pull the ejection handle. And

don't forget, the Air Force wants these pilots to eject and save themselves.

There is no shame in ejecting ever, even from a billion dollar bomber.

Reeve doesn't have time to think about his decision.

The B-2's left wing is now scraping the ground.

Explosives tear a hole in the fuselage above the cockpit, and rockets eject the

pilots from the aircraft.

The stealth bomber hits the ground and bursts into flames.

Alert one, alert one, runway six, Romeo, runway six, Romeo.

I'm stunned.

The B-2 has gone through 19 years and three wars without a crash. This is

unheard of.

One of the world's most advanced warplanes has been incinerated during a

routine takeoff.

The whole world is left wondering what went wrong.

For two straight days, firefighters at Anderson Air Force Base in Guam battle

the flaming wreckage of B-2 bomber Spirit of Kansas.

With a price tag of $2 billion, this is the most expensive aviation accident of

all time.

The crash at Guam did shake us to the core in that we want to know what the

heck just happened.

Operations of the entire B-2 fleet are suspended even before an investigation

is launched.

It's bad to have to stand down the B-2 flying operations.

On the other hand, they have no choice. They have no idea what's gone wrong

inside that B-2 and they have to find out before they risk any more B-2s in

flight.

The US Air Force appoints the well-respected General Floyd Carpenter

to lead the investigation.

Because of the high-profile nature of this accident, I think they expect a lot

of media interest.

And so as a senior brigadier general, I was picked, I think, to get the

airplanes back operational and cleared to fly again.

You're never going to believe this.

Investigators watch the accident unfold on security video.

Great to have the video, and we were able to glean a lot of information from

it.

Video of the takeoff shows that as the plane lifted off, it pitched nose high.

Your first reaction when you see that airplane pitch up is like, what are they

doing?

The plane then drifts left before the left wing scrapes the ground.

Left wing falls off and hits the ground.

And through that whole thing, you're thinking, where is the crew?

First time you see it, you probably don't realize the crew actually ejects.

Can you take it back for me please?

Stop.

That's the pilots.

One and two.

The video shows the pilots ejecting just as the plane hits the ground.

Both pilots have been taken to hospital for evaluation.

Justin Grieve has suffered a serious back injury from the forces of the

ejection.

It was a waiting process for us and gathering all the other information

while we waited to talk to them and hear their side of what really happened.

Investigators study the mechanical and computer systems that control the jet.

Perfect. What about the actuator?

We had so much of the aircraft already available, actuators, engines, all those

things are what you're really looking for in this type of accident.

They quickly determined that all of the plane's flight control surfaces were

functioning on takeoff.

Pretty quickly, we were able to rule out the fact that the engines were not a

problem, the hydraulics weren't a problem, the flight controls were not a

problem.

Pull these from the video.

Up.

Up. Up.

It's a beautiful sunny morning. Why does a bomber pitch its nose up and crash in

a fireball on the runway at Guam?

Is this a weight and balance issue?

In any deployment like that, it's not uncommon to load aircraft with spare

parts or other equipment that you might want to get home and not wait to ship

home.

Some classified material going back to Whiteman.

Personal belongings.

Gear.

So center gravity became a big issue for us. Could it have been that?

Not enough to disrupt their balance, sir.

The B-2 is capable of carrying 40,000 pounds of weaponry.

But Spirit of Kansas wasn't carrying any bombs or other heavy cargo that could

have shifted on takeoff.

We found out that there really wasn't a lot of equipment. There were no

munitions being carried.

So everything was in balance as it should have been, and so center of

gravity was ruled out pretty quick.

Investigators look more closely at the takeoff rolls of both B-2s on the day of

the accident.

For clues as to why Spirit of Kansas couldn't get airborne like the plane

just ahead of it, Spirit of South Carolina.

Okay, pause it right here.

Okay.

So South Carolina lifts off just past that taxiway.

Right about here.

Because we did have video, we were able to look at the takeoff roll of the lead

aircraft compared to the second aircraft.

And stop.

Okay, our guys lift off just past that runway light, which is

this guy.

Right here.

Look at that.

We found out that Spirit Kansas took off 1,500 feet shorter than its lead

aircraft.

What is going on?

Again, video helped us understand that takeoff roll was shorter, but didn't

understand why.

The investigators turn to data from the bomber's flight recorder for answers.

The plane is still on the ground, 546 feet above sea level.

Not 682.

So the altitude is off by 136 feet.

Now, sir, there is no way he got up to 145 knots using only this much runway.

Agreed. Something happened to cause this airplane to pitch up.

But so far, we've ruled out all the easy stuff. And so now we start looking into

other situations that could have caused an aircraft to do what it did.

Now here, sir, the nose is lifting off the ground, but the plane registers a

pitch down of minus eight degrees.

Now, obviously, this plane is not pitching down, but the computer thinks

it is.

That is why I tried to lift the nose higher and higher and higher.

Until it stalled.

Once we got the performance parameters of the aircraft and we were able to

determine that the airplane thought that it was negative 8 degrees angle of

attack, then you start going back to say, why did it think that?

The heart of the B-2 bomber is its sophisticated onboard computer, known as

its Flight Control System, or FCS.

Without it, it would be impossible for pilots to make all the calculations

necessary to keep the unusual aircraft flying.

You don't have a tail.

Think about that. You don't have any kind of vertical empennage.

It's just a big flying wing.

Accurate data is crucial.

On a B-2, pilots tell the computer what they want the plane to do, and the

computer determines how to accomplish that.

The flight computers move the surfaces of this airplane in a way that's not

intuitive to any pilot of any other aircraft.

Simply put, it'd be nearly impossible to fly this airplane safely without flight

computers.

So, airspeed, climb angle, and altitude are all off.

How does that happen on this plane?

Investigators need to determine why the stealth bomber was getting faulty data.

Let's see what the pilots can tell us.

We weren't looking to blame them or, you know, point the finger at them, but

there were tough questions to ask.

Three weeks after the accident, the pilots of Spirit of Kansas agree to be

interviewed by investigators.

Okay, Captain.

How about we take it from the top?

We started up at 915.

A few minutes later, Major Link saw the calibration message during startup.

The pilots tell investigators that they received an unusual computer message

shortly after startup.

Never seen that.

Me neither.

Hey, Chief, we're seeing an Air Data Cal message. Can you send someone up here to

clear that up?

Air Data Cal stands for Air Data Calibration.

In the simplest terms, the air data calibration gives the aircraft its

orientation to the universe.

There are 24 sensors, flush-mounted near the nose of the B-2, that constantly

measure air pressure.

The plane's computer uses those readings to calculate altitude, airspeed, and

angle of attack.

All 24 systems have memory in them, and they're measuring themselves against all

the others.

And so if they get out of balance, if one is reading too low or too high, it

calls for an air data calibration, and the pilots see that.

When that occurs, they call out maintenance.

Okay.

Let's see what we can do to clear this for you.

Can you put it in maintenance mode for me?

That's good.

You're good to go, sir.

Thank you.

So they have these 24 sensors. They make sure they're communicating correctly.

And if they do, they let it go forward.

Keto heat is on.

Less than an hour later.

Clear right.

Good to line up. The pilots maneuver the massive bomber to the start of the

runway.

Okay. Go on.

Everything was 100% routine until we had 100 knots.

That's when we got the FCS master caution.

You got a master caution while you were still on the ground?

Yes, sir.

Just a flicker.

100 knots.

before I could even push the button and rescind it itself.

What was that?

FCS caution.

After 100 knots to our decision rotate speed, we will abort for safety of

flight items.

We define safety of flight as we are unable to control this airplane or

there's something on the runway you're going to hit.

Stop or go?

Go. Warning rescinded.

In that scenario, if I was the pilot in command, I would continue.

Why? It's not safety of flight.

145, rotate.

When we hit 145, I called for Major Lind to rotate.

Then it all very quickly went to hell.

They lift off.

The flight control computer senses a problem, so it pitches up.

Pilots try to go nose down.

Full power.

They go max power, but the airplane is trying to stall them.

Major Link was trying to push it back down, but it wasn't working.

He wasn't having any effect on the plane. We were basically just along for

the ride.

And the left wing just drops.

And I know we're done.

We gotta get out.

Then I pulled the handles.

If the airplane did not perform as advertised, it was time for them to get

out. and give the aircraft back to the taxpayers.

Thank you for your time today, Captain.

Thank you, sir.

They were extremely forthcoming in their testimony.

They survived it, but they had no understanding of what happened either.

Investigators need to know more about the calibration that Grieve reported in

his testimony.

It's not part of the plane's regular start-up procedure.

If a sensor provides a reading that differs significantly from the others, a

recalibration is done that tells the wayward sensors how much they're off in

order to bring them back into agreement with the others.

These three weren't just off by a little.

They are way off.

And they need a very big adjustment to get them in line with the rest.

And we're not sure why, sir.

100 knots.

A master caution alarm that flickered on for a few seconds just before takeoff

becomes a key piece of the puzzle.

At that point, we really didn't know how they're related, but we figured they

might be. There was too much coincidence starting to happen that pointed to these

things. What was that?

FCS caution.

The recalibrated sensor started providing faulty error data again.

Six seconds later... Stop or go?

Go. The flight computer resolved the discrepancy between the sensors and

canceled the warning.

What is going on with this plane's sensors?

They have a mystery flaw in the B-2, puts the 509th and the Air Force under a

lot of pressure. They have to find out exactly what went wrong with the flight

controls in order to return that fleet to safe operations.

And the world will be watching them.

Okay, so let's start at the top.

Why the need to recalibrate in the first place?

It was a procedure that a lot of pilots had never seen, and maintainers didn't

do very often.

Investigators look for any abnormalities in the mission that might have had an

effect on the B-2's sensors.

Huh.

So, they got delayed by a day.

What had happened was Whiteman Air Force Base in Missouri had a severe snowstorm.

It was snowing quite heavily. Visibility was near zero.

So what we did is we delayed the mission to come home 24 hours.

Spirit of Kansas was left on the tarmac while the pilots waited to resume their

mission.

Okay.

So the jet was left outside for 24 hours because of the delay.

So what?

Check the weather.

Second to last page.

Holy smokes.

That is one hell of a lot of rain.

Weather records show that a tropical rainstorm settled over the airbase the

night before the accident.

Tell me a rainstorm didn't take down a two billion dollar airplane.

Decisions were made and these B-2s were left outside in this particularly

heavy rainstorm.

Okay, let's fly these two.

Investigators run tests on B2 sensors to determine the effect rain may have had

on them.

And stop.

Gotta be kidding me.

Tests confirm that the sensors exposed to the heaviest rainfall got saturated

and needed recalibrating.

Even prior to that, when it was in test and development, We'd never experienced

that much rain on the system, so no one really knew how that would adversely

affect the operations of the B-2.

The reason no one realized how heavy rain affects the B-2 is that it's almost

always parked inside a hangar at Whiteman Air Force Base overnight.

Even if it's flying a mission over Afghanistan or Libya, it returns to

Missouri.

The B-2's occasional deployment to Guam presented different weather conditions.

Could heavy rain be the simple explanation for this accident?

This would not have happened in a desert environment. This would not have

happened at Whiteman. But Guam is very unique. They left the B-2 parked out all

night in the rain. The moisture got in there.

Something just doesn't add up.

They did the recalibration.

You're good to go, sir.

But they still ended up with faulty data.

They nearly killed him. Yeah.

Wow.

A state-of-the-art military jet put itself into a storm because it was

getting faulty data about its climb angle.

Investigators still don't know why.

The B-2 has always operated under so much pressure and scrutiny.

If they can't figure out what went wrong that morning on Guam, honestly, this

could be the end of the B-2 bomber program.

Okay, so they recalibrate at

0934.

Nearly an hour later...

The master caution lights up because of an air data issue.

So, what happens in those 56 minutes?

Investigators review what the pilots told them about the flight.

Routine taxi.

They hit the pitot heat, wait for the timer, and they're off.

So, what about this?

There are small heaters connected to each of the plane's sensors.

Just before takeoff, the pilots activate the heaters so the sensors don't freeze

up when the plane reaches cooler temperatures at higher altitudes.

We can't take off, advance to power, and go down the runway until we put the

pitot heat on.

Pitot heat is on. It's essential that those sensors are getting heated.

Investigators wonder if the pitot heat could have affected the recalibrated

sensors.

Clear right.

Get to line up.

We didn't know enough to really put them together.

And so we had to go get better understanding of the system. And we did

that through engineers that actually built the system.

When he saw the frequency of our calibrations, he was surprised and

concerned.

And then they turn on pitot heat when they get to the runway.

And then... He was really concerned when he saw and understood, like he only

could, that with moisture in the system and the data that we were putting into

it to fix it could cause such a problem.

On the day of the accident, turning on the pitot heat had a consequence that no

one anticipated.

Recalibrating the sensors brought the three wet ones in line with the others.

But turning on the pitot heat... boiled away the moisture, bringing the sensors

back out of alignment.

Last time CT.

So the data that was put in on the calibration now is invalid again and the

flight computers are now trying to resolve the issue with these sensors.

But the discovery doesn't explain another key event during the short

flight.

What was that?

FCS caution.

Why did the faulty air data warning disappear six seconds after it came on?

Stop or go?

Go. Warning received.

It's seconds from takeoff.

U.S. Air Force investigators look into the logic guiding the B-2's flight

computer. So it has to make a choice.

The flight data computer needs a solution.

And what we mean by that is it can't spend even a second or a millisecond

wondering where it is and what needs to be done.

The B-2's flight computer is constantly receiving four separate data streams

from all 24 sensors.

If there's a discrepancy in the values of those channels, the computer is

programmed to select any two of the channels to proceed.

It just chose wrong.

Yeah, we should fix that.

Now it's voting as to throw out bad data, what they think is bad data, keep

the good data, and it resolves the issue.

The light goes away. The flight computers are now good to go.

And so the pilots are now, okay, well, that must have just been a glitch.

Let's keep going.

Stop or go?

Go. Warning rescinded.

The flight computer chose the two channels that included the faulty sensor

data.

1-45, rotate.

Twelve seconds later, the plane pitched up abnormally because of the faulty air

data readings.

Once they rotated the aircraft on speed, as they thought, and left the ground,

they were along for the ride at that point.

But if recalibrating the plane's sensors before turning on the pitot heat can be

catastrophic, why was that the official procedure?

So hardly any at all.

Investigators learned that recalibrations are rarely done while the

B-2 is at its home base in Missouri.

But during a deployment in Guam in 2006, maintenance personnel were performing

frequent recalibrations.

Copy that. I'm on my way.

They knew there was a challenge, but they didn't know what it was.

And they did speculate that because of the...

weather in Guam raining a lot more than at home, that it might be an issue of

moisture.

Technicians in Guam spoke to an engineer in the U.S. who suggested a procedure to

remedy the frequent air data calibrations.

Yeah, then we have to do an onboard recalibration.

They were able to talk to an engineer that said, well, before you do a data

calibration, try turning on the pitot heat.

and burning that water out of the system and see if that'll take care of it. I

haven't tried that.

Good idea, though.

The technician passed on the suggestion to the B-2 pilots in Guam.

Try turning on your pitot heat for 40 seconds instead.

Copy.

Apparently I should do it.

Yeah, but our guys didn't do that.

Can you think of a reason why?

Investigators learn from technicians at Whiteman Air Force Base that the

procedure for activating pitot heat in response to an air data calibration

message was not officially adopted.

Really?

Why the heck not?

Some crews knew about it.

Some did not.

Pilots back at Whiteman who were not there, never heard of it, and

maintainers had never heard of it.

There's nothing.

There's nothing anywhere about using pitot heat when a calibration message

appears.

You're good to go, sir.

Neither Ryan Link, Justin Grieve, nor the maintainer assigned to their plane

was ever told about the moisture issue or the informal procedure for rectifying

it. Better?

Yeah, it looks good.

The maintainers that morning were following the tech orders, which tell

them exactly what to do in the pre-flight.

But for some reason, this new workaround to compensate for the moisture just

hadn't made it into the manual.

And that's a little bit of a tragedy.

So these three are wrong.

What if they'd used pitot heat instead of recalibrating?

It would have burned off the excess moisture.

It solved the problem.

No faulty air data.

No accident.

If information had been shared from previous deployment 2006 to 2008, this

accident could have been prevented.

Hey, Chief, we're seeing an air data cal message. Can you send someone up here to

clear that up?

The maintenance personnel that came out to the aircraft that day of the accident

did everything exactly right.

They were just doing the procedure they were taught.

It doesn't seem like anybody understood what these recalibrations could do.

The investigation has uncovered a catastrophic gap in the B-2 crew's

understanding of the link between calibrating sensors and flight controls.

145, rotate. There's no way a pilot or a maintainer would understand the system

well enough to realize what could have happened when they did that data

calibration.

That lack of understanding left the crew of Spirit of Kansas vulnerable to the

effects of the faulty data Investigators now wonder if there was something the

pilots could have done to save their plane

18

seconds to get this plane under control Was it even possible?

Investigators re-examine the crash sequence to see if the pilots of the B-2

bomber Spirit of Kansas could have prevented their aircraft from crashing

at Guam.

145 rotate.

Certainly no B-2 pilot wanted to be the first to eject from a B-2.

Plane goes full nose up.

He pushes full forward.

and goes full power.

Plane starts yawing and rolling left.

He applies right stick.

He's fighting.

Investigators determined that Major Link took the correct action to save the B-2

bomber.

But because of its low altitude and slow speed, disaster was unavoidable.

Ultimately, this was a no-win situation for the crew.

As we determined with hundreds and hundreds of simulations afterwards, no

one could have flown this aircraft out of that situation.

The data also shows just how close the pilots came to losing their lives.

They are seconds away from impact, and they still hadn't pulled the handle.

If they had delayed even a fraction of a second later to eject, they most likely

would not have survived.

The video of the accident shows that the plane's left wing was already scraping

the ground when the pilots ejected.

We've got to get out.

They are heroes in the sense that these guys waited till the very last possible

second. I don't know of many other people that can say that they waited

till the wingtip hit the ground before ejecting. Can you imagine that?

All pilots in the Air Force are good or maybe even great.

But these guys were truly outstanding.

And they were very, very close, despite everything, to actually saving that

aircraft.

One of the most sophisticated warplanes on Earth was brought down by a

combination of poor weather. Who would have guessed that a bit of moisture

would have led to all this?

And poor communication, which left Grieve and Link without an understanding

of how recalibrating their sensors could lead to a serious flight control issue.

100 knots.

This accident didn't happen because of bad data.

Not because of bad software, not because of bad weather, not because of bad

decision making.

145, rotate.

It happened because of bad communication.

In the end, safety is everything.

It doesn't matter if it's an airliner, a fighter jet, a space plane, or a stealth

bomber. Full power. Safety is critical, and safety depends on communication.

The Air Force investigation underscores the need for pilots to be kept informed

about the technology controlling their airplanes.

Do you really, really want to leave the defense of your families, your children,

your grandchildren to a computer?

Or do you want to leave it to the greatest asset that we have, and that is

the human brain?

In spite of being involved in the most expensive aviation disaster in history,

Major Ryan Link and Captain Justin Grieve went on to have successful

military careers.

The B-2 was back in the air two months after the crash.

The flight computer was redesigned to prevent faulty air data.

The procedure for using pitot heat instead of recalibrating the sensors

is documented in Air Force manuals and technical documents.

There hasn't been an issue with faulty air data since.

Northrop produced an amazing aircraft and I commend them and the maintainers

and the aviators that continue to make the B-2 the envy of the world.