Original subtitles

In the final months of Hitler's Third Reich, at a remote airfield deep inside Nazi Germany,

a top-secret jet fighter makes its first flight.

This is the Horten 229,

a Nazi weapon that might have changed the very outcome of the war.

The Horten 229 had to be the most exotic piece of machinery in Germany at that time.

But was it truly stealth?

It's one of the last great mysteries of World War Two.

Now, more than sixty years after it took to the skies...

...an elite team of aeronautical engineers and stealth experts...

Yeah, we lost it; it's over!

...reconstruct one of the Third Reich's most incredible secrets.

- It's great, it's in! - I've never moved a German stealth fighter before.

They'll put the Nazi flying wing to the test-

- to unlock the mystery of Hitler's Stealth Fighter.

In the final months of World War II -

Allied forces speed across Germany in a desperate search.

Intelligence reports suggest Hitler's Third Reich -

- has a secret weapon that could change the outcome of the war.

On April 14th 1945, the -

US 3rd Army discovers a top-secret facility hidden in the woods -

one-hundred miles northeast of Frankfurt.

Inside, they find one of Nazi Germany's most advanced weapons...

...made almost entirely of wood.

The soldiers must have been stunned when those doors opened up -

- and for the first time they see this aircraft, with its unearthly shape,

something that know one had seen before: A jet engine powered wooden aircraft.

It would have been impossible for them to understand the magnitude of what they had discovered.

In July 1945-

- the Horten 229 and other advanced Nazi aircraft are shipped back to the United States -

- under the codename "Operation Seahorse".

The batwing fighter is reassembled-

- but its flying and stealth capabilities are never tested.

For the last six decades, the only surviving Horten 229-

has remained hidden in the shadows and away from prying eyes.

Generations ahead of its time-

the coveted Nazi war prize remains under tight security along with other US artefacts-

- here inside a government warehouse outside of Washington DC.

Sixty-four years after the Horten 229 took to the skies-

- the debate about its stealth capability is about to be settled.

It's amazing that the Germans were that far along in World War Two.

It's amazing that of the technology that existed during the timeframe-

- that they could come up with this type of a vehicle.

Stealth expert and aircraft designer Tom Dobrenz-

- will lead a team from the aerospace company Northrop Grumman-

- in building a full-scale replica of the Horten 229.

Once complete, they'll then test its stealth ability against World War Two allied radar.

After the Battle of Britain Goring came out and said we need to find new flying machines:

"What we have now is ineffective."

It wasn't ineffective ; they had good flying machines- it was the radar that destroyed them!

Most of what is known about the 229, was gathered by David Myhra-

- during his meetings with the planes designers, Walter and Reimar Horten-

- before they died in the 1990s.

OK, Aldo... Diameter of the exhaust liner...

The team has been given a few precious hours to examine and take measurements of the original German jet-

- plane constructed almost entirely of wood.

...three-quarters of an inch.

The layers of veneer suggest the plywood may have prohibited the radar from penetrating the skin.

Was it truly something that they were trying to defeat a radar system-

- and that's going to be something we're going to try and find out.

To solve the mystery, they'll first test the plywood skin.

This will help us determine whether energy is being absorbed or reflected-

- or maybe shielding the inside of vehicle itself from energy.

They'll use a pair of radar-emitting probes to focus electromagnetic energy against the plywood skin-

- to see if it absorbs radar.

It seems like the surface itself isn't conductive-

- but it maybe absorbing the signal.

So there's a good possibility that this could have been built as-

- if anything maybe not even absorbing but just possibly shielding.

The test confirms the wood improved the fighter's detection range-

- but it's not the only stealth feature on the Horten aircraft.

It's got buried engines in the fuselage.

All the surfaces are blended.

You got the carbon in the skin and then to say-

- we're they thinking about radar? Well everything points to that.

This is the modern shape of stealth: The Northrop Grumman B-2 bomber.

This expansive flying wing embodies both engineering elegance-

- and all aspect stealth.

Although it spans more than 170 feet, its radar cross-section-

- the amount of electromagnetic energy it reflects back to the radar-

- is smaller than that of an eagle.

To reduce its signature, stealth aircraft like the B-2, rely on two critical factors:

Materials that absorb this energy-

- and more importantly, a shape that prevents it from returning to the radar.

Stealth technology doesn't make an aircraft invisible-

- but what it can do is dramatically reduce its detection range-

- making it much more difficult to defend against using fighters and anti-aircraft weapons.

Modern stealth aircraft were developed by aerospace companies like Northrop Grumman-

- in secret facilities starting in the 1970s.

A lot of the things we've been doing over the years-

- is kept in a cloak of secrecy.

Most of the time, the things I work at Northrop are programs I'm not allowed to talk about.

Much of that top-secret works happens here-

- at the company's advanced design and manufacturing facility-

- in the Los Angeles suburb of El Segundo.

It's also where they'll build the Horten 229 over the next three months.

While it won't be designed to fly, like the original, it will be a full-scale replica -

- constructed around a center-body flanked by a pair of outer wing panels.

Right now we're building the rotator.

Tim Knott's model shop team begins assembling the center-body-

from blueprints reproduced from the Horten brothers original drawings.

OK, lets stick it together.

Like the original Horten fighter, they'll use glue and nails to fasten the parts.

While the shape of the replica is critical to its radar-cross-section or RCS testing...

...so are the materials.

Most of it is wood and there are few parts that are going to be made out of fibreglass-

- but the only metal parts are the rotator and the lifting points.

Gus Kindweiler and Tim Knott have spent their careers working on-

- Northrop's most advanced stealth programs.

They'll assemble the model's center-body around a metal rotator.

The majority of RCS models built by Northrop Grumman are classified-

- most are destroyed after stealth testing is complete -

- the rotator is the only part that is reused.

This rotator box was used on a different program, another classified program.

I really can't tell you what it is but its seen its fair share of action.

When complete, the rotator will be used to attach the model to a pole-

- five-stories above the ground.

They'll then direct radar at the fighter to determine its stealth.

The idea to build the original 229-

a German aircraft virtually undetectable to allied radar-

- was born in the aftermath of one of the most pivotal battles of World War Two.

In preparation for Hitler's planned invasion of Great Britain in the summer of 1940-

- Hermann Goring unleashes the Luftwaffe-

- with orders to destroy the Royal Air Force.

But the British have a secret weapon.

What gave the British the defensive edge they needed was radar.

This was a new technology that provided accurate-

- range, altitude and the numbers of German aircraft-

- as they approached across the English Channel.

Britain's Chain Home network of radar stations proves critical-

- in directing RAF fighters who cut down the German invaders.

That was the one technology that completely alleviated the advantage the Germans had-

- with their overwhelming number of aircraft.

The Battle of Britain proved to be the pivotal point in the air war and radar was the key.

In an effort to recapture Luftwaffe supremacy, Goring envisions a new fighter-

- employing the latest in state-of-the-art German technology.

Officially the concept was known as "3x1000":

That is a fighter that could fly a thousand kilometres an hour-

- over a 1000 km distance and deliver a 1000 kilogram bomb on target.

It was pushing the limit of any known aviation technology of the day.

As members of the Hitler Youth, Reimar and Walter Horten became consumed-

- with the idea of creating an aircraft that flew with the elegant efficiency of birds.

In the early 1930s, the self-taught aircraft designers-

- began building and piloting a series of tailless wooden gliders.

To meet Goring's requirements the brothers began modifying their flying wing-

- around a recent innovation: the jet engine.

If their concept worked, it promised to leave the allies defenceless.

Walter & Reimar's brother Wolfram was killed in the Battle of Britain-

- as Wolfram was laying mines along the French coast in a Heinkel 111.

Walter still burned with revenge for losing all his friends in the Battle of Britain.

So he wanted to go back to England to attack the British Chain Home Radar Network.

The Horten 229, brain child of Walter-

- and was generations ahead of any other aircraft developed in the world.

Of the proposals reviewed by Goring for his new fighter, only one aircraft met his requirements.

It was a radical design submitted by two brothers he'd never heard of.

The flying wing was a radical concept to everyone including Goring-

- and the idea that it was made out of wood, just added to his scepticism.

Walter is so consumed with the passion for this plane that he sort of pulls Goring into the whole idea, saying:

"We do it, we can build this from wood, with jet engines we can make it fly a 1000 km/hour."

"We can give it a thousand kilometre range, we can deliver the payloads you need."

And Goring just said: "I'm just astounded by this machine and the shape", he says, "no tail, no elevator?"

Walter said: "It's going to be so manoeuvrable against allied fighters and bombers."

"It's going to sweep the skies clean for you."

So Goring is so taken by Walter's vision-

- that he buys in completely to a flying wing.

And Goring just said: "Go do this, build it for me and make it fly."

The Hortens left the meeting with Goring knowing that they had won the contract to build the 3x1000 flying machine-

- and now they felt they had been vindicated.

More than a half-century later-

- the team at Northrop Grumman begins constructing the wings for their Horten 229.

This is going to be a big model, over fifty-feet wingspan and we're going to need a lot of wood to build this model.

We're trying to build it similar to what they built it back in WWII.

Even though it's only a model, they must insure its shape and the materials used in its construction-

- mimic the original aircraft for the radar testing to be valid.

Just painting the back of the wing is enough to represent the tanks?

Yeah, because actually...

...at the frequencies and the wavelengths that these radars worked at they were very long-

- and this was an aluminium metallic tank and I think if we paint it with some conductive materials-

- it will represent part of the structure of that tank to the radar.

We're actually going to be painting in this back area here-

- and probably we will do some outside painting-

- when the vehicle is fully assembled.

Now it's going to be getting it to stay, gluing it.

Tim Knott and the model shop crew at Northrop Grumman-

- are one of the few teams in the world building new stealth concepts.

They're an elite and eclectic group who've spent most of their careers working in the shadows.

It's nice to have a chance to build these models and then -

- we get to see what they look like even before they come into production.

They'll construct the wings in two major subassemblies-

- first they'll build a long curved leading edge-

- wrap it in wood and then bolt it to the main wing panel.

It's being built in about a quarter of the time that a normal RCS model would be built.

Normally this is a year effort and we're doing this in three months.

Give me a nail right here, cause I know I'm good here.

I didn't even know there was something this advanced in those days.

I can imagine it have done with the war if they would have got successful with it.

OK, ready.

We can't let go of this its popping.

Yeah, keep going down.

The team at Northrop Grumman will use a combination of old world craftsmanship and modern tools-

- to recreate the 1940s flying wing.

We're using foam to manufacture the wing tip of the Horten aircraft.

Machining it is just a lot easier so by carefully controlling what kind of paint we put over it-

- it will have the same radar reflective properties as the wood that it's mounted onto.

In little more than a week, they glue and nail together the eighty ribs -

- that make up each of the outer wing panels.

We're simulating what would normally be the fuel tank in the Horten.

This is real silver paint. It's silver suspended in a polyurethane coating-

- and it's rather expensive, about twenty-five hundred dollars a gallon.

OK, that will look like two fuel tanks to radar.

Keeping true to the materials the Nazis used on the Horten 229,-

- they skin each wing with plywood.

It's always great to see major subassemblies coming together.

A month into the build, they've finished the leading edges-

- and are ready to bolt them to the outer wing panels.

Down a little bit, just a little... Push it in.

But where there's wood, there's warpage.

There's a gap between the pieces because this piece of wood is warped out from the water.

It looks like a half-inch.

There's always a little warping so that's why these guys designed it so they could put a bunch of the fasteners in afterwards -

- to just take care of the warping to get a really good solid assembly.

We're just filling it in with resin and cabosil-

- and we're going to put a layer of fibreglass on there.

To ensure there are no imperfections that will create unwanted radar reflections,-

- the team spends hours in a cloud of fine dust painstakingly sanding each wing panel.

When they're testing the model up on the pole and the RCS -

- they don't like to see any humps or sharp edges at all or gaps.

Anything that, and it could be a rivet, it could be an edge, it could be anything,-

- they'll get a return and that's not good.

Northrop Grumman has a long history building wings.

Like the Horten brothers, company founder Jack Northrop -

- was convinced, tailless aircraft -

- would one day revolutionize military aviation.

More than decade before the Nazi's began working on their all wing fighter,-

- back in the United States Jack Northrop was already flight-testing flying wing designs of his own.

After World War Two, the Northrop YB-49 became -

- the US Air Force's leading contender as its first intercontinental bomber.

Now, decades later,-

Northrop is recreating a flying wing with a much darker past.

Worked myself into the model.

With the internal structure of the Horten 229's center body assembled,-

- Gus Kindweiler and Jeremy Osborne get to work skinning it with plywood.

That's good right there.

We're using flex-board, wood that's not real strong-

- and the reason we're using it on the leading edge-

- is so we can use just use one piece and wrap it around the bulkhead.

I need a third hand here.

Like the finished outer wing panels,-

- they'll construct the complex shape of the center-body primarily of wood.

To insure the amount of electromagnetic energy the 229 reflects back to the radar is accurate,-

- Northrop Grumman will replicate two of the most vulnerable areas on a stealth aircraft:

the metal cockpit and inlets.

The engine shrouds flanking the cockpit will be fabricated by Bill Marsh and Mark Ferrari.

On the original plane itself it was welded steel.

This is made out of carbon fiber which is a lot lighter, easier to layup.

Simulates the metal.

To reduce the amount of handcrafted parts,-

- they use a sintering machine to rapid prototype the engine turbine blades.

The sintering machine is ideal for replicating complex, one-of-a-kind parts,-

- capable of creating any shape-

- by melting thin layers of powdered nylon.

This kind of technology is called additive layer and what it does -

- is you start with nothing and you make only what you need.

We grow this overnight and it's completely finished. All the holes, everything is there.

In less than a day, the turbine blades are finished and ready to be assembled.

For the radar testing, they must insure the nylon and fibreglass parts-

- have the same conductive properties as metal.

In the area of the inlets what we end up doing is that we take a reflective paint-

- and we coat the outside of the shape-

- so that from the radar standpoint it doesn't know whether it's was a piece of fibreglass underneath-

- or it's a piece of steel or aluminium.

I think in the 40's, the how the brothers made this canopy,-

- they started out with a flat sheet and they bend and screw it, heat it up and keep bending and forcing.

The cockpit of the 229 is a big opening and vulnerable to radar.

Modern stealth aircraft use special coatings on the canopy-

- to prevent electromagnetic energy from entering the cockpit-

- and bouncing back to the radar.

In order to keep the replica faithful to the original aircraft for its radar testing,-

- the team decides to use 1940s material and techniques to form it,-

- but it's a complex shape and time is running out.

- How do you say one, two, three in German? - Eins, Zwei, Drei.

Yah, we lost it. It's over.

- It's over, it aint gonna work no more. We're done. - We're going to have to give it another shot.

We're gonna cut this out so this area is relieved and then this will lay down a lot better.

After reheating the plexiglass, the team makes a second attempt-

- to shape the canopy in one piece.

We've lost it. OK nice effort.

We're not going to give up so what I'm going to do is do it in two pieces.

I'm going to eliminate half the problem.

With the inlets and nozzles metalized the team pushes forward to complete the center-body.

The radar coming in this direction because the plane is heading toward the target-

- so the radar is coming in at this angle and you have turning fan blades that reflect the radar-

- so this is very vulnerable area of the aircraft for RCS.

When I get out of here Mark let's start working on the nozzles and put the foam in.

- Clockwise... - Right there.

I don't think we need to move it except to paint underneath it.

OK, I think we're ready.

They attach the carbon fiber engine shrouds to both sides of the cockpit.

Like the wings, the center-body is filled and sanded smooth-

- to insure the shape of the model is as close to original aircraft as possible.

Shut the door.

With the plexiglass now cut in half, Steve Simpson makes another try at forming the canopy.

- I think this might work. - This is looking good.

OK, somebody get the middle quickly.

You see that we have a shape. I think its success.

I'll just polish that sucker with a buffing wheel and it will be nice.

I think the Germans did the real one in two pieces.

- Down. - OK, that's good.

Push it, push it forward.

We're good.

Go a little more north.

Looks great, its in.

With the outer wing panels attached,-

- the last component of the center-body is ready for installation.

Yeah, I'm in the hole go ahead.

Using a litany of materials including the plastic pipe you might find under your kitchen sink,-

- Gary Hethcoat has built an accurate cockpit of the German fighter.

OK. Look at that man!

Having this all correct is really good-

- because it's going to have all the correct surfaces to come in and reflect off of-

- so we really have a true representation of the real plane.

With the cockpit and canopy installed,-

- the team undertakes one last step to insure the plane is ready for radar testing.

This paint is supposed to simulate real metal to the radar-

- because we want this to be exactly like the real aircraft was-

- and right now I'm checking the resistance here against real metal-

- and then coming over here and I'm comparing that to the the metalized area we painted-

- and they're identical right now and that's exactly what we wanted to achieve here.

Although assembly is complete, the team has less than two weeks to paint and finish the replica-

- before its radar testing is scheduled to begin.

Sixty-four years earlier, at a secret hangar deep inside Nazi Germany,-

- the Horten 229 was being readied for its first test flight.

At the top secret Sonderkommando 9,-

- the Horten brothers are overseeing preparations-

- for the first flight of their stealth fighter.

The war is about to enter its sixth year-

- and allied bombers continue relentlessly pounding Nazi Germany.

On June 6th, 1944-

- Hitler's grip on Europe suffers a crippling blow-

- as the allies land on the beaches at Normandy.

By the fall of 1944, work on the 229 is nearly complete when the Hortens receive word-

- that the Fuhrer is now desperate for a long-range bomber.

Adolf Hitler had a dream of taking war to the United States-

- and would describe in detail to confidants like Speer how he dreamed of destroying cities like New York-

- to knock down the skyscrapers to leave them in flames.

Reimar spent three weeks in December of 1944-

- designing the intercontinental bomber known as the Horten 18.

It was going to be an expanded version of the Horten 229.

As the brothers work in seclusion on Hitler's America Bomber,-

- their flying wing fighter is about to make history.

December 18, 1944.

Just before dawn, pilot Erwin Ziller watches-

- as the ground crew rolls the bat-wing fighter from the hangar.

Although a highly experienced test pilot,-

- this will be the first time a jet powered flying wing has ever been flown.

The Horten 229 was generations ahead of any other aircraft developed in the world-

- and the Horten 229 had to be the most exotic piece of machinery-

- in Germany at that time.

In the frigid winter air, Ziller nudges the throttles forward-

- and begins his take off roll.

When the 229 flies for the first time it's vindication and validation for the Hortens'-

- and ironically the brothers aren't even there to see it.

They're busy working around the clock on their design for the America bomber.

In January 1945, Walter Horten returns to Berlin-

- to brief Goring on the brothers' design for a long-range bomber, the Horten 18.

Walter shows Goring the concept, a bigger version of the 229,-

- a 142 foot wingspan, jet engines... Goring is stunned.

In their conversations Goring was very clear to Walter that he needed this new aircraft-

- because by 1946 Germany would have a functioning nuclear weapon.

While the Hortens' attention focuses on their flying wing bomber,-

- test flights of the 229 continue.

Over the following months Ziller flew the Horten 229 numerous times-

- and it performed way beyond the Hortens' expectations.

In fact Ziller even flew it in a dogfight against a Messerschmitt Me-262,-

- and it out performed them in dogfighting abilities, manoeuvrability and speed.

While the flying wing uses the same jet engines as the Me-262,-

- its new propulsion system lacks reliability.

On a test flight in February 1945, Ziller's right engine flames out.

Unable to regain control, he crashes the crippled fighter into the German countryside.

Exactly two months after his first flight in the 229,-

- test pilot Erwin Ziller is dead.

After a gruelling three-month build schedule,-

- the Northrop Grumman team rolls open the doors to its classified model shop-

- and gives employees a chance to see the Nazi fighter first hand.

No one's more excited to show off his creation than Tim Knott.

Alright so here it is, it's done.

I tell you, you guys got to be proud of yourselves with what you've done?

- I mean this thing looks absolutely fantastic. - Thank you, we're really proud of it.

Among those interested in the all-wing fighter-

- are the designers of Northrop's B-2 bomber Irv Wayland and John Cashen.

You did a great job. I tell you what, there's nobody better in this business than you guys.

After working twenty-eight years in the dark, it's nice to spend one day in the light you know.

You know most of what we do in here over the years never sees the light of day you know.

It's nice to let people...

...see what goes on.

You don't get the opportunity to work on something like this...

...with history behind it-

- and that's what made it a little bit special.

The other thing is...

...that it's got my heart and soul in it, there's a lot of me in there.

I can't wait to see it up on the pole.

I want to see if it's stealthy, it looks stealthy. It certainly looks stealthy.

Finally now we'll get real answers, some real data-

- that will tell us how stealthy it really was so that's awesome.

In a remote part of the Mojave desert sits Northrop Grumman's Tejon Test Range.

Built in the late 1970s,-

its numerous dishes can precisely measure an aircraft's stealth capabilities.

From these inconspicuous hangars have emerged a stunning array of stealth designs.

Security is incredibly tight and access is granted to a select few.

This is the first time cameras have ever been allowed at this desolate test site.

Going up.

The surfaces we've been working on are going to taste electromagnetic radiation pretty soon.

This is the first time radar is going to be shot at this aircraft ever.

This it, this is the day we've been waiting for.

Great weather. You can't beat this.

I've moved a lot of stuff, but never moved a German stealth fighter before.

- Yeah we're good. - Wow, awesome!

This is the first time we're actually getting a feel for what it looks like as if it was flying.

While it won't actually fly, the 229 will be mounted five stories off the ground-

- so radar can be shot at it.

I'm just at a loss for words, this just looks so cool!

It just changes the whole perspective to see it that far away and up in the air.

With delicate precision they lower the German fighter onto the RCS pole.

Three-months of work hang in the balance.

- It looks great up there! - Oh it does.

As far as stealth characteristics and everything we always as an American we feel like that's our deal.

We're the ones doing the stealth stuff, never had no idea-

- that the Germans were doing a wing back in the 40s.

- It looks great it really does. - Time for the moment of truth.

Six decades after the first flight of the Horten fighter,-

- the legend of its stealth is about to meet reality.

Deep inside a secure control room on the edge of California's Tehachapi Mountains,-

- the Northrop Grumman team is about to do something the Nazis never did...

...test the stealth of the Horten flying wing.

To get a complete picture of the fighter's stealth capabilities,-

- they'll rotate the Horten 229 to illuminate it by radar from every angle.

We're pretty much doing level and nose on for the first set of spins.

Each rotation does a frequency band.

We're doing VHF, UHF and L band.

This wide range of frequencies will give-

- Dobrenz and his team a better idea of the fighter's radar-cross-section.

So we want to make sure we get enough of that data-

- in order to characterize in each one of those systems how the vehicle performed.

OK, we're starting our next spin now.

At this frequency you can tend to see a lot more of the characteristics of the inlets and the canopy area-

- up in the front of the vehicle.

The inlets specifically, where energy is down and hitting the front of the engine frame is showing up-

- and the bowframe and the canopy and just energy that's getting into the cockpit area and rattling around itself.

They want to determine if the Nazi fighter could have indeed penetrated-

- the radar array along the British coast known as the Chain Home system.

I'll be really fascinated to see how after we process the data and get some numbers-

- about what the performance of this aircraft really would have been like against the Chain Home radar system.

We have to do a lot of the post processing in order to get the actual numbers that we can use for comparison-

- against the fighters and bombers of the day.

Inside their advanced air combat facility, Northrop Grumman can test the capability-

- of nearly any aircraft in the world.

It's here they'll conduct the second test-

- on the Horten 229, flying it in a simulated attack on Britain,-

- and hitting it with allied radar to determine its stealth.

Flying the jet will be Paul TP Smith.

TP was the chief test pilot in the competition to build the US military's newest stealth fighter,-

- the F-35.

Roger, I've got altitude 20,000 feet, 600 knots.

TP will approach the British coastline from a variety of altitudes.

His target, a Chain Home radar station.

In the Battle of Britain, Chain Home Radar System had a range of about 100 to 110 miles-

- which could see across the channel and into France.

They could see the German fighters marshalling before they ever crossed the channel.

To help reduce their detection range,-

- German aircraft began flying across the English Channel at altitudes as low as fifty-feet.

But by early 1945, any chance for a German victory had been lost.

By mid April, the allies are closing in on the Nazi's Sonderkommando 9.

Although they've nearly finished a second 229, the Horten brothers flee,-

- leaving behind their dream of arming the Luftwaffe with flying wing fighters and long-range bombers.

Sixty-three years after the surviving Horten 229 was discovered by the US Army-

- and shipped back to the United States,-

- the bat-wing fighter begins to reveal its secrets.

Is that canopy in the center that's lighting up or is that blending from the inlets?

Well it's probably a combination of both.

Again, when you get down to these kind of wavelengths a lot of the scattering elements tend to blend together.

You can see that the nose, the inlets, that canopy area-

- that's where a major part of the radar reflection was coming from.

It looks like with all data-

- that this aircraft would have made a major, major difference.

All in all it's about a 20% reduction in the actual detection range.

Once detected by radar,-

- a conventional fighter of the time approaching at high altitude-

- takes nineteen minutes to reach the target.

With its stealth and speed advantage,-

- the Horten 229 covers the same distance in less than eight minutes.

While the Horten advantage in detection range is on the order of 20%,-

- the combination of speed and stealth was absolutely lethal.

But even if you did detect it, it was so fast it would have been extremely difficult-

- for any of the allied fighters at the time to have been able to catch it.

You can imagine the amount of improvement-

- that the Horten 229 could have given to the German warfighter.

I surely wouldn't have wanted to be the allied forces.

Had the 229 adopted the low level tactics employed by the Luftwaffe,-

- the results could have been devastating.

When you're flying at 50 feet and travelling around 600 miles an hour-

- plus the reduction in the detection range-

- now you've got only two and half minutes-

- of reaction time for the allies to know you were coming.

Looking at it, your response time then with low altitude,-

- when you only have twenty-four miles that's two and half minutes. You just don't have the time to respond.

If you can keep them from seeing you and getting their defensive systems up-

- you create such an element of surprise-

- you can now basically roam at will and attack the targets you want to.

The Horten 229 aircraft design predates modern stealth technology by more than three-decades.

If the Germans had deployed it in great numbers-

- it would have been a game changer.

After decades of speculation and debate,-

- Northrop Grumman has finally unlocked the mysteries of the Nazi stealth fighter.

But the 229 wasn't the only Horten stealth aircraft-

- ordered into production.

The characteristics and things we saw on the Horten 229-

- would translate directly to the Horten 18-

- which was the larger version of the Horten 229.

Goring was very clear that by 1946 they would have a nuclear bomb-

- and the Horten 18 would be used to deliver-

- that bomb on an American city like New York or Washington.

Even if you managed to detect a Horten 18 bomber-

- approaching the east coast of the United States-

- you probably would have had only about eight minutes of warning time-

- which would have been totally inadequate to mount any defence against it.

While the stealth flying wing would have been a lethal fighter,-

- its use as Hitler's long-range bomber is unthinkable.

It's a terrifying thought in a lot of ways-

- because if the Third Reich was able to use them operationally-

- before the Allies understood they were there-

- those first few strikes with those airplanes could have been devastating.