Enter the Draken – How Sweden Built a Double Delta Masterpiece | SAAB J35 DRAKEN

In April 1940, the radio in the Swedish Air Staff operations room crackled with a voice that changed everything.

“Oslo airport is in German hands. Repeat, Oslo airport has been seized.”

The officers around the table froze. Cigarette smoke hung motionless in the air. On the wall, a map of Scandinavia was already crowded with pins and penciled arrows, but this… this needed no annotation. Norway was next door. Too close. The news moved across the room like a cold wind.

Colonel Lindström, whose hair had gone gray somewhere between the Munich crisis and the invasion of Poland, said nothing for several long seconds. He simply stared at the map, at the narrow ribbon of land that separated Sweden from the Axis war machine.

Then an aide hurried in with a cable from Washington.

“Sir, it’s from the Americans. About the aircraft order.”

The colonel took the sheet, read it once, and read it again, as if repetition might change the ink.

The United States, worried that any planes sent to Sweden might end up in German hands, was cutting off deliveries. Of the 316 modern aircraft Sweden had ordered, they would receive just sixty-two.

The rest would simply vanish into American inventories, swallowed without ceremony.

The colonel let the paper fall onto the table.

“So,” he said quietly, “we are neutral. And alone.”

He didn’t raise his voice, but the room heard the verdict clearly.

At the stroke of a pen, Germany’s invasion of Oslo had become Sweden’s own Pearl Harbor—not a bombardment of ships, but a brutal lesson. In a world at war, a neutral country that relied on foreign aircraft could wake up one morning and discover its sky was defenseless.

That day planted a seed, deep and stubborn: never again.

If Sweden was going to survive the storms sweeping over Europe, she would need more than good intentions and diplomatic notes.

She would need her own wings.

Nine years later, in the winter of 1949, a young engineer named Erik Bratt sat alone at a drafting table in a small town called Linköping, staring at a blank sheet of paper that felt heavier than steel.

Outside, snow whispered against the factory windows. Inside, the air smelled of oil, paper, and the faint ozone tang of early fluorescent lights. On his desk lay a slide rule, a sharp pencil, and the thin folder labeled:

Project 1200 – Supersonic Interceptor Requirements.

He had read the pages so many times the words were burned into him.

Single engine.
Rapid climb to high altitude.
All-weather, day and night.
Operation from 800-meter road bases in forest clearings.
Fully serviceable by conscripts with basic tools.
Capable of destroying Soviet bombers before they crossed Swedish airspace.

And one more line, the one that made his hand tighten around the pencil every time he looked at it:

“Maximum speed: Mach 1.4 minimum. Growth potential required.”

Speed creep, they called that. A polite way of saying: whatever you build, it had better be faster than what the enemy is dreaming up.

In 1947, news of the Bell X-1’s supersonic flight had reached Sweden. For most of the world it was a milestone, a curiosity, a headline about a rocket plane somewhere over the California desert. For the small team at Svenska Aeroplan AB—SAAB—it was something else.

It was an invitation.

If supersonic flight was possible, then Sweden’s next fighter would be supersonic. That decision, in Stockholm, had taken about five minutes.

Figuring out how to make it real now sat in front of Erik, in the empty hush of the design office.

He touched the pencil to the page.

“Okay,” he murmured to himself. “Let’s build a dragon.”

Erik wasn’t a dreamer who’d wandered into engineering by mistake. He’d earned his degree from the Royal Institute of Technology in Stockholm in 1942, the hardest years of the war. Years when Sweden tried to stand still while the world tore itself apart. But his education hadn’t stopped at lectures and chalkboards.

He had also earned his pilot’s wings.

In 1940, he’d trained as a reserve pilot in the Swedish Air Force—one of the “Silver Wings” reservists. He’d flown in icy skies over forests and lakes, felt the tremor of the stick in his hand, the shudder of buffeting air. He knew what it meant when an instrument needle wandered where it shouldn’t. He knew the difference between a smooth landing and one that left your teeth rattling.

That dual identity—pilot and engineer—was rare. It meant that when he drew a line on paper, he could imagine exactly how it would feel through the seat of a pilot’s pants.

He leafed again through the Project 1200 file, past the technical specifics, to the pages that explained why Sweden was about to bet her future on his pencil.

On the other side of the Baltic Sea, within easy flying distance, sat a superpower that no longer needed anyone’s permission to rearrange borders. The Soviet Union now had nuclear weapons, delivered by bombers with range enough to reach Western Europe.

Finland, Sweden’s eastern neighbor, had been battered in the Winter War and forced into a tight dance of constrained neutrality. They walked a narrow line—independent in name, sensitive in practice to Soviet wishes.

To the west, Norway had joined NATO.

Sweden, who had stayed neutral through two world wars, now found herself in the crosshairs of a confrontation she wanted no part of, but couldn’t ignore.

If the Soviets ever chose to send bombers west—to Norway, to Britain, to the Atlantic—they would likely fly over or near Sweden. Geography didn’t care about neutrality.

Sweden’s answer was brutally pragmatic:

If we can’t join an alliance, we will defend our neutrality by making any violation ruinously expensive.

Somebody in Moscow needed to look at a map, look at the distance from Soviet bases to targets in Norway or the North Sea, and realize that every bomber crossing Swedish territory would have to fight for every mile. Fight, and pay in metal and blood.

Maybe, if that price looked high enough, they would think twice.

That was the theory.

The reality depended on Erik’s blank page.

“Bratt,” a voice said behind him.

He turned. In the doorway stood Lars Brising, SAAB’s chief project leader. Older, heavier, with the easy slouch of a man who had spent half his life around drafting tables and noisy hangars.

“The Air Board sent their requirements?” Brising asked.

Erik nodded. “Yes. They want the impossible.”

Brising smiled thinly. “Naturally. That’s why they came to us.”

He stepped inside, closed the door, and pulled up a chair.

“Walk me through it,” he said.

Erik summarized. The climb rate needed to be ferocious—fast enough to reach high-flying intruders before they got anywhere near strategic targets. The fighter had to operate from short stretches of reinforced highway, roughly eight hundred meters long and barely wider than a two-lane road, hidden among trees.

Dispersal doctrine, the Bas 60 concept, had been hammered out after air staff officers digested photographs of obliterated German and British air bases. Big, obvious airfields were invitations to be vaporized in the first minutes of a war.

If war came, Sweden’s fighters wouldn’t sit in neat rows on concrete runways. They would scatter like cats at the first sound of a door opening, vanishing into forests, operating from improvised wartime road bases with camouflaged revetments.

You couldn’t destroy what you couldn’t find.

But that doctrine had a twist.

The people maintaining these fighters, out on damp stretches of road surrounded by trees, wouldn’t be elite technicians with years of specialized training. They would mostly be conscripts. Eighteen-year-olds in gray-green uniforms, wearing thick gloves in winter, working quickly in the rain and dark.

Refuel, rearm, perform basic checks, get the aircraft back into the air.

Ten minutes. No complicated tools.

If the design couldn’t be turned around by conscripts on a forest road in ten minutes, Bas 60 fell apart. Then Sweden had no credible air defense.

“So,” Brising said, “we need a supersonic interceptor that can sprint like a demon, land like a gentleman, and be fixed by teenagers with a wrench.”

“Yes,” Erik said dryly. “Is that all?”

He hesitated—then added the part that weighed on him the most.

“And there’s the Soviet problem. The specification says Mach 1.4, but you know as well as I do that their bombers won’t stand still. They’ll get higher and faster. Speed creep. If we design for 1.4 and they show up at 1.7, we’re dead.”

Brising tapped the folder with a finger. “Then we don’t design for the minimum. We build the bones for more. Even if we can’t reach Mach 2 now, the airframe must be ready to grow into it.”

He looked at the blank page, then back at Erik.

“Welcome to the job.”

“I thought this assignment was temporary,” Erik said. “Until someone with more supersonic experience can be found.”

Brising laughed, a single hoarse bark.

“Supersonic experience? In Sweden?” he said. “Apart from the Bell X-1, the only aircraft that have gone through the sound barrier are test beds in America. Nobody has designed a supersonic fighter, not really. Not production. Not yet.”

He stood, hands on hips.

“There is no one with more experience,” he said. “Congratulations. You are now Sweden’s leading supersonic aircraft designer.”

The team that gathered around Project 1200 in late 1949 was small. A dozen engineers at first. They shared cramped offices, one overworked slide rule machine, and a sense that they were about to try climbing a mountain nobody else had even seen.

They weren’t entirely alone. After the war, as the Allies divided up the remains of German research, a handful of aerodynamicists found their way to Sweden. Men like Klaus Oswatitsch, Siegfried Erdmann, and Hermann Behrbohm—ex-Peenemünde and Messerschmitt minds who had spent years wrestling with high-speed airflow before their world collapsed.

They brought with them thick notebooks, habits of thought, and scars from programs that had flown too close to the edge.

During one early meeting, Behrbohm stood in front of a blackboard, chalk dust on his fingers, and sketched a straight wing, then swept it back.

“At Mach 0.8,” he said in a soft accented voice, “this will behave nicely. Lower compressibility, better transonic handling. You know that already, from Sabre and MiG-15.”

He flicked the chalk. Wing swept further.

“Past Mach 1.4,” he continued, “wave drag comes like a wall. Thick wing, swept or not, bad. We tried. Many people tried.”

Then he wiped the board, drew a delta—a big triangle.

“Pure deltas,” he said. “Good for high supersonic. Thin, stiff, low drag. Mirage, perhaps, will be like this. But…”

He drew a small stick figure of a pilot landing, nose high, trailing a long arrow of runway.

“At low speed, you need big angle of attack. Vortices help, yes, but you fly like this.”

He tilted his hand, palm up at a steep angle.

“On big airfields, maybe acceptable. On your short forest roads? No.”

Low-speed handling and short-field performance on one hand. High supersonic performance on the other. Every solution for one seemed to punish the other.

They tried everything.

Swept wings with tails, without tails. Pure deltas with different aspect ratios. Variable geometry ideas that belonged in science fiction pulps more than budget reports. Models piled up on shelves. Calculations filled notebooks. And every time they thought they were close, some number refused to cooperate.

If they sized a pure delta for fuel and structure, the wing area exploded. Great for landing. Terrible for transonic drag. If they cut the area down for high speed, landing speeds climbed, and runway length requirements blew past what a forest highway strip could offer.

Weeks became months. The pressure mounted.

In the spring of 1950, with Project 1200 designs filling drawers and no clear answer in sight, Erik sat up late one night, alone in the office, tracing a triangle over and over.

The wing planform glared back at him. Too big, too draggy. Too small, too unforgiving.

He stared at the line near the fuselage.

We need thickness here, he thought. For fuel, for landing gear, for strength. But we don’t need all that area outboard.

What if…

He picked up the pencil.

What if the wing doesn’t have to be one idea?

He drew the inner section of the wing, swept sharply, almost absurdly, toward the rear. Eighty degrees. Far more than the thirty or forty of typical swept wings.

Then, at some distance outboard, he changed the angle. Broke the line. The outer panel swept more gently, like a conventional delta’s edge.

The result looked… wrong.

Like a triangle that had been bent and snapped.

A double-delta.

He sat back, heart beating a little faster.

The inner wing, with its extreme sweep and long chord, would behave like a razor-thin high-speed wing at Mach 1.5 or more, even if it was physically thick near the fuselage. The thickness-to-chord ratio would stay low; the wing would “feel” thin to the air, even as it hid fuel tanks and landing gear in its deep root.

Outboard, the less-swept panel would provide more traditional lift and control at lower speeds, making takeoffs and landings manageable. And when the nose came up at high angle of attack, the sharp leading edge of the inner wing could generate vortices—spiraling tubes of low-pressure air—that would cling to the wing and feed the outer panels, keeping the flow attached.

High-speed performance and low-speed control, married on paper.

He stared at the drawing for a long time.

It looked like a child’s kite. Or a mythical dragon’s wing.

Or a broken triangle that could save a country.

The next morning, he unrolled the drawing in front of the team.

For a few seconds, there was only silence.

Then a young aerodynamicist frowned. “It looks… wrong,” he said. “Broken.”

Another engineer narrowed his eyes. “Aerodynamically, the inner panel could be treated like a very thin swept wing,” he mused. “If the vortex behavior is predictable…”

“Or catastrophic,” someone muttered.

The German experts approached the drawing like bomb disposal technicians.

“It is unconventional,” Behrbohm admitted, tracing the crank with a finger. “But not insane. The idea of leading-edge vortices is sound. You will need a lot of testing.”

“Wind tunnels,” Erik said. “Models. Whatever it takes.”

They agreed to study it. Skeptically, but seriously.

A few weeks later, the drawing sat on a different table.

The air smelled of aftershave and uniform wool. Major General Bengt Jacobsson, second in command of the Swedish Air Board, stood over the designs while Bratt and Brising walked him through two options.

The conventional “safe” one: a swept-wing interceptor with horizontal tail.

And the radical one: the tailless double-delta.

Erik explained the trade-offs in measured, careful Swedish. Lighter, more predictable aerodynamics at high speed for the double-delta. Better landing performance from vortex lift. Lower drag in the transonic regime.

Jacobsson listened, his face giving away nothing.

At the end of the briefing, Brising cleared his throat. “General,” he asked, “do you have any comments?”

Jacobsson looked at the broken-triangle drawing, then at the more familiar swept-wing layout. The room held its breath.

“You can build the damned airplane however you want,” he said at last. “But it shall have a tail.”

After he left, Bratt and Brising shared a look.

“Make some drawings of the double-delta with a tail,” Brising said finally. “Something we can pull out when the generals come to visit. Then we put them away and do the real work.”

They laughed, but it was a strained sound. The compromise was political, not aerodynamic.

The argument wasn’t over.

It ended in a different room, with a different general.

The Chief of the Air Force, Bengt Nordenskiöld, arrived in Linköping on a gray morning with a small entourage and the quiet authority of a man used to making decisions that made other people sweat.

He listened to the same presentation. Saw the same two drawings. Heard the same pros and cons.

At the end, he asked one question.

“Which aircraft is best?”

Erik didn’t hesitate. “In my opinion, the double-delta is best,” he said.

Nordenskiöld nodded, as if confirming something he already suspected.

“Then why are you working on anything else?” he asked. “From now on, you work only on that aircraft.”

Then he stood up and left.

No more hedging. No more safety blankets. No more tails on paper to soothe worried brass.

By May 1950, the conventional Project 1220 was officially shelved.

Sweden had gone all-in on a wing that looked like it had been damaged in transit.

Now they had to prove it wouldn’t get pilots killed.

Proving it meant testing. And testing meant facilities that Sweden barely had.

In 1950, the country possessed exactly one supersonic wind tunnel. It could test 1:50 scale models that fit in your hand, whisper-fast blasts of air skimming over tiny wings.

The engineers quickly discovered that at that scale, you couldn’t trust the results in the messy transonic region where shock waves formed and did nasty, complicated things. They needed larger models. Higher Reynolds numbers. Closer approximations to reality.

So they built their own transonic tunnel at Linköping.

They also leaned on friends. The National Aeronautical Research Establishment in Stockholm. The Royal Institute of Technology. Even NASA’s wind tunnels at Langley and Ames, far across the Atlantic.

Wherever a model of the double-delta went, it left behind pages of data: pressure distributions, drag curves, shock positions. Graphs with dots and lines that either confirmed their equations or tore them apart.

They fed those numbers into BESK, the government’s hulking vacuum-tube computer in Stockholm. BESK took up an entire room, its cabinets humming and glowing like something out of a science-fiction magazine. It drank electricity like a steel mill and in return spit out calculations that would have taken human mathematicians months.

Equations, load cases, performance predictions—reams of punched cards and printouts.

Wind tunnels were one thing. Real life was another.

They built a thirty-foot Ferris-wheel rig, bolted fuel tanks into it, and spun them under load, watching how fuel sloshed and slammed at high G. In a tight turn or sudden pull-up, the fuel inside a wing tank could surge forward or backward, shifting the aircraft’s center of gravity and turning a stable machine into an unstable one in a heartbeat.

Better to find that out with a spinning rig and pressure sensors than with a test pilot pulling on the stick at low altitude.

They built a climatic chamber large enough to swallow major components and freeze them down to temperatures no Swedish winter could match, then pump out the air until the pressure mocked an altitude of nearly a hundred thousand feet. Metal shrank. Rubber seals stiffened. Hydraulic fluid became sluggish. They recorded every creak and crack.

They fired frozen chickens at cockpit windscreens using compressed air guns, the great birds turned into tragic, feathery projectiles. At a thousand miles per hour, a one-kilogram bird slamming into glass hit with the force of dozens of rifle bullets arriving at once. Windscreens shattered. Others cracked. Eventually, they found shapes and laminates that would hold.

The floor of the test hall looked like an abattoir. Someone joked that the chickens had served Sweden’s defense just as surely as the pilots would.

Every test was a question.

Every surviving component was an answer.

And yet, for all the tunnels and computers and spinning rigs, there remained one question that could only be answered one way.

Would the double-delta actually fly?

In early 1950, SAAB made a decision that would save them years and perhaps lives.

They would not go straight from paper to full-scale Draken.

They would build a little dragon first.

The SAAB 210—nicknamed Lilldraken, the Little Dragon—would be a flying laboratory. A half-scale proof of concept. If it flew nicely, the double-delta could be trusted. If it tried to kill its pilot, better that it did so at four meters nose to tail than at fifteen.

The design went to the experimental workshop in February 1951.

Twenty months. That was the schedule from rubber stamp to first flight.

The workshop was a forest of scaffolding, rivet guns, and aluminum sheets. Men in overalls moved around the growing skeleton of the 210, their breath steaming in the cold air that seeped through the hangar doors.

They built it like any other aircraft: stressed-skin aluminum over ribs and spars. But they made choices that hinted at improvisation.

They borrowed an ejection seat from the older J 21 fighter. They gave Lilldraken a simple nose intake—two oval inlets split by a small central cone at first, later reshaped. The landing gear was semi-retractable: hydraulics pulled it up, but there were no doors; the wheels hung partly exposed under the wing, ugly but adequate. Gravity, not complexity, would bring it down.

For power, they chose an Armstrong Siddeley Adder turbojet. It wheezed out a little over a thousand pounds of thrust—just enough to get the small machine into the air and up to around 370 miles per hour. They didn’t need speed records. They needed stability and handling data.

Inside the fuselage, they installed something clever.

Two trim tanks—one forward, one aft—filled with water-glycol. By pumping liquid between them, the pilot could move the center of gravity forward or backward during flight, taming odd behaviors or provoking them intentionally. Later, they replaced the system with removable weights for simplicity, but the idea gave them invaluable flexibility early on.

By November 1951, Lilldraken sat on its landing gear under the hangar lights, paint gleaming, its strange double-delta wings stretching out like a mythic bird ready to leap.

During initial tests, another problem surfaced. The control servos—hydraulic actuators that moved the elevons—shook themselves nearly to pieces when the engine ran at certain RPMs. On the bench, powered by a long hydraulic hose connected to an external pump, they’d been fine. In the aircraft, with shorter lines, pressure spikes hammered them.

The solution was to put back what they’d accidentally had before: they ran an eight-meter hydraulic hose inside the wing, acting as a damper, smoothing pressure pulses. Sometimes engineering progress meant discovering why an accident had worked and then making it permanent.

December arrived, bringing short days and angry weather. Test pilot Bengt Olow taxied Lilldraken up and down the runway, feeling out its behavior. At 110 miles an hour, the little machine felt light on its wheels, teasing the edge of flight. Once or twice, it hopped—lifting a meter into the air before slapping back down.

Enough to prove the wing could lift. Not enough to know what it would do once fully committed.

Weeks of snow and cloud followed.

On January 21, 1952, the sky over Linköping finally cleared. Cold, pale blue. Light winds.

Olow climbed into the cramped cockpit, strapped himself in, and ran through the checklist.

Hydraulics. Fuel. Instruments. Controls free.

He advanced the throttle. The Adder engine spooled up with a rising whine. Lilldraken rolled onto the runway.

At around 110 miles an hour, he eased the stick back.

The nose lifted.

The wheels left the ground.

Lilldraken climbed, light and sure, into the winter sky.

For twenty-five minutes, he flew gentle circles above the field. Feeling the aircraft in pitch, roll, yaw. Listening for vibrations. Watching the behavior of the strange cranked wing at different speeds and angles.

No sudden departures. No vicious stalls. It flew like an airplane, not like an experiment gone rogue.

Landing was another matter. The delta wing required a high angle of attack for approach, nose pitched up, forward visibility sacrificed. On this first flight, Olow chose caution: a long, shallow glide that kept the nose relatively low, eating up half the runway.

The wheels touched at around 120 miles an hour. The aircraft rolled out and came to a stop.

The double-delta had flown.

The sigh that went through SAAB that day was almost physical. Years of equations and arguments and late nights finally had proof in aluminum and airflow.

They gave the machine a proper name: Draken.

The Kite. The Dragon.

Though, as Erik later admitted, he wasn’t particularly fond of the name. It felt a little too dramatic for a man who triple-checked sums. But the name stuck. The shape demanded it.

Over the next four years, Lilldraken worked for her living.

Test after test. Hundreds of flights. Different intake geometries. Different control settings. Tufts of wool glued across the wing, filmed by a fin-mounted camera to reveal airflow patterns. Pilots speaking into tape recorders as they flew, calling out speeds and attitudes, their voices steady even when their hands were not.

In early 1953, test pilot Olle Klinker took Lilldraken up for what looked on paper like a routine flight: explore the low-speed end of the envelope, incrementally, to find the stall characteristics.

He slowed, nose coming up, angle of attack increasing.

Seventy knots. Seventy-five. Eighty.

Around eighty miles per hour and roughly twenty-five degrees nose-up, the world went sideways.

The nose snapped upward violently, pitching toward vertical. Then it fell through just as violently. The aircraft began to oscillate—nose up, nose down—in a slow, sickening pendulum. It rolled gently left. The altitude unwound like a clock spring.

Klinker pulled the stick forward. Nothing. Pulled it back. Nothing.

Lilldraken had entered what would later be called a superstall. The wing wasn’t stalling like a conventional aircraft. It wasn’t breaking and spinning. It was simply… stopped. The airflow separated across most of the surface, vortices gone. The controls, immersed in dead air, had nothing to bite.

The aircraft became a falling, stable brick.

Three thousand feet.

Two thousand.

A thousand.

The ejection handle was between his knees, waiting.

He watched the oscillation.

When the nose swung through the low point, the airspeed flickered upward for a heartbeat. The elevons bit, just a little. The aircraft responded, slightly.

Now, he thought.

He hauled the stick fully aft, then at the forward swing, slammed it forward. The nose dipped, the airflow reattached over the wing, vortices formed, and the Dragon woke up.

He leveled out with perhaps three hundred feet to spare.

Back on the ground, engineers pulled the data apart. The lesson became doctrine: to recover from this strange stall, a pilot had to do something that would have horrified generations raised on conventional aircraft—pull full aft, then push forward at just the right moment.

It was counterintuitive, dangerous, and absolutely vital. They wrote it into training manuals long before the word “superstall” became common.

Years later, a Soviet test pilot in a different delta-wing aircraft would discover a similar phenomenon over another airfield. He too would ride the physics to survival. But in 1953, Klinker’s experience was unique, a glimpse into the weird aerodynamics of the double-delta world.

Lilldraken kept flying until 1956, long after the big Draken took shape. When the small aircraft finally retired, it was wheeled into the Swedish Air Force Museum, its engine removed, its skin scarred by years of experiments.

It looked small, almost fragile.

But it had given Sweden something enormous: confidence.

While Lilldraken chased vortices, another drama was unfolding in engine rooms and boardrooms.

Sweden had always wanted its own engines. Relying on foreign powerplants was exactly the kind of dependency they’d sworn off after 1940. Two companies, Svenska Flygmotor and STAL, had been developing turbojets. STAL’s axial-flow designs, Dovern and its planned big brother Glan, were the pride of the program.

Dovern, a compact nine-stage engine with nine combustion chambers, had finally run successfully after thousands of design tweaks. Turbine blades that sheared off from resonance were redesigned. Bearings that overheated were cooled and lubricated differently. Each failure added a note to a thickening book of hard-earned knowledge.

By 1952, the Swedes had mounted Dovern under an Avro Lancaster and flown it for hundreds of hours. It produced around 7,300 pounds of thrust. Glan, intended for Draken, promised over 11,000 pounds dry, even more with afterburner.

In an office where the air stank of stale coffee and stress, engineers pored over charts of compressor maps and turbine temperatures, believing they were on the cusp of joining the select club of nations with independent jet engine capability.

Then, in November 1952, the order came down.

Cancel Dovern.

Cancel Glan.

Immediately.

The decision landed like a physical blow. Men who had spent years wrestling metal and flame stared at the memo as if it were a betrayal.

The reason sat neatly on another set of papers.

Rolls-Royce, in Britain, had made an offer.

License the Avon engine to Sweden on generous terms. Full technological access. The right to build current and future versions at Svenska Flygmotor. Technical assistance. In effect, Britain would hand over the keys to a proven, powerful turbojet—and Sweden would stop pouring money into domestic designs.

Dovern had flown for three hundred hours. Avon had tens of thousands. Dovern still had problems lurking in the corners. Avon’s had mostly been solved.

A small country of seven million could only stretch its budget so far.

The choice was brutal, and practical.

Glan would never howl in a Draken. Dovern would never pull an operational fighter into the sky. They would remain as photographs and metal skeletons in test cells.

For the men who had dreamed of Sweden-powered wings, it felt like defeat.

For Draken, it meant life.

The Avon, license-built as the RM 5 and later RM 6, would give the interceptor the thrust it needed to chase bombers to the stratosphere. Swedish engineers would design their own afterburners, the EBK series, mating British core to Swedish flame.

The Air Board saw it as a necessary compromise, one that kept the country’s industry focused on airframes and systems rather than trying to tackle everything at once.

SAAB, whether they liked it or not, now had an engine.

On October 25, 1955, three and a half years after Lilldraken’s cautious first hop, a full-sized double-delta fighter sat at the end of the runway in Linköping.

Fpl 35-1. Stordraken.

The Big Dragon.

Where Lilldraken had fit into a large garage, Stordraken loomed over the tarmac. Its wings spanned almost ten meters. Its length, from sharp nose to tail, was over fifteen. The double-delta planform that had seemed odd on paper now looked… right. Predatory. Like something designed not by committee, but by physics.

Under the skin lay the RM 5A turbojet, a license-built Avon without afterburner for the prototype. Enough for supersonic in a dive, they hoped. The production aircraft would have the afterburning RM 6.

Test pilot Bengt Olow, older now, with lines around his eyes and the memory of Lilldraken’s first flight in his bones, climbed into the cockpit.

He strapped in, flicked switches, watched gauges come alive.

Taxiing out, he felt the weight and the responsiveness—heavier than the little test machine, but familiar in the way the nose bobbed, the way the wing moved over humps in the concrete.

He lined up.

For a moment, he sat there, hands steady on the throttle and stick, looking down the long strip of runway toward the trees.

Somewhere on the other side of the Baltic, Soviet bomber crews were practicing their own runs, checking their own instruments. Somewhere else, politicians in distant capitals were making speeches about peace while quietly stockpiling weapons.

The Dragon was about to join that world.

He released the brakes and eased the throttle forward. The RM 5A gathered itself and pushed. Draken accelerated, the double-delta wings slicing air that thickened with speed.

At around 150 miles an hour, he pulled gently on the stick.

The nose lifted without drama.

The main gear left the ground.

The Big Dragon climbed.

He kept the first flight conservative. Gentle turns. Modest speed. Feeling out the controls. The q-feel system, which mimicked aerodynamic resistance in the stick, told his hand what his eyes were confirming: the aircraft was responsive, perhaps a bit too eager in pitch, but fundamentally sound.

Landing required the same long, shallow approach style they had used on Lilldraken. The nose-high sight picture was still strange compared to conventional fighters, but manageable.

Touchdown. Rollout. Stop.

Bratt, watching from the ground, let out a breath he hadn’t realized he was holding.

All the tunnels, all the simulations, all the Argus-eyed examinations of data, all the late nights over slide rules and cold coffee—they hadn’t lied.

The double-delta worked at full scale.

The second prototype, Fpl 35-2, added the real teeth.

It had a more powerful Avon Mark 46 and an operational afterburner.

On its first flight in March 1956, the test pilot climbed away from the field, leveled off, and thumbed the afterburner switch.

The EBK lit with a guttural, hungry roar. The extra thrust slammed him into the seat. The Mach needle crept upward.

Then, as the aircraft still climbed, it passed through Mach 1.

Supersonic.

By accident.

Later, engineers would shake their heads affectionately. “Only a Swede,” someone would joke, “could break the sound barrier by mistake.”

But beneath the humor was something serious. The wing and fuselage did exactly what they were supposed to do. No violent transonic buffeting. No pitch-up or loss of control.

Months earlier, in January 1956, 35-1 had already gone supersonic in level flight without afterburner, the uprated Avon Mark 43 nudging the aircraft past Mach 1. The Dragon could slip past the sound barrier on dry thrust alone.

For an interceptor designed to reach Soviet bombers, that mattered. It meant the afterburner, and its fuel thirst, could be reserved for the climb and final dash.

Success bred confidence.

Confidence, in test programs, is always tempered by what comes next.

In aviation, problems rarely show up on cue. They arrive uninvited, at the worst possible moment.

During one landing in 1956, Olow, flying 35-2, reached for the brake parachute handle and, in a moment’s confusion, selected the landing gear lever instead.

The aircraft was still rolling. The gear folded. Draken dropped onto her belly and slid, sending up a shower of sparks and shredded metal.

Olow climbed out unhurt. The prototype was not so lucky. Months of repair lay ahead.

A few weeks later, 35-1 gained altitude for another test flight. On final approach, test pilot K-E Fernberg hit the switch to lower the gear.

No green lights. No red. Nothing.

He cycled the gear. Still nothing.

Indicator failure? Gear failure? Both?

With fuel running low, there was only one choice. He brought Draken in for a belly landing on the far side of the main runway. The aircraft slid, metal shrieking. Fernberg’s back took the impact, rewarded with an injury that would ache in the winter for years. But he survived.

Post-incident tests of the gear system suggested it worked flawlessly. Whether the gear had been down but unindicated, or genuinely failed, remained a matter of speculation.

What was clear was that SAAB’s test program now had two of three prototypes sitting damaged in hangars.

The Dragon project, as one engineer dryly put it, was “completely stuffed.”

The third prototype, 35-3, saved them.

First flown in September 1956, it was the first fitted with cannon armament—a sign that Draken was finally being treated not just as a flight laboratory but as a future weapon. As 35-1 and 35-2 returned to service, all three aircraft carried the burden of finding every quirk and flaw before the fighter reached the hands of squadron pilots.

They found plenty.

Draken, like many deltas, was sensitive in pitch.

The elevons—combined elevator and aileron surfaces—sat far aft on the wing, giving them considerable leverage. Small deflections translated into significant pitch changes, especially at approach speeds when the wing was riding high on its vortices.

Pilots transitioning from conventional trainers quickly discovered that ham-fisted inputs produced oscillations—nose bobbing up and down during landing in a cycle that could amplify if not corrected.

One pilot joked that the oscillations could be triggered by his heartbeat.

Bosse Engberg, who later wrote about his experiences, recalled the first time he came in nose-high, peering past the edge of the instrument panel at the runway ahead, having to look sideways around the canopy frame.

“Raising the nose immediately demanded more thrust,” he said. “It felt like balancing on the edge of a table. New, awkward—and then, gradually, natural.”

SAAB tweaked the control system, refining the q-feel and mixing to reduce sensitivity. Draken never became a forgiving trainer. She remained what she was built to be: a thoroughbred interceptor that demanded respect.

At high speed and low altitude, another issue lurked.

During aggressive pull-ups at transonic speeds, pilots discovered that yanking the stick sometimes didn’t produce the expected response. The thin, high-speed air hammered the elevons so hard that the hydraulic actuators simply couldn’t drive them to full deflection.

The controls had hit their own version of a stall.

Servo stall, the engineers called it, with their usual gift for understatement.

Left unaddressed, it meant that a pilot diving toward the ground at Mach 0.9, pulling with all his strength, might find the nose answering too slowly.

Dead pilots don’t care about elegant aerodynamic theories.

SAAB’s answer was to use the airbrakes as allies.

They modified the system so that when a pilot pulled more than a preset force on the stick—around thirteen pounds—the upper airbrakes on the wing would automatically deploy partially, acting as maneuvering flaps. The added drag and altered airflow helped pitch the nose up, assisting the struggling elevons.

It worked, but it also highlighted delta-wing realities. Draken could pull hard, generating enormous lift at high angles of attack, but that lift came with massive drag. In a tight turn, her drag rose like a wall. Airspeed bled away quickly. For an interceptor, designed to climb and sprint rather than joust in prolonged dogfights, it was acceptable.

She would never be a turning champion. She would be a killer of bombers.

For that job, her climb performance was a thing of cold beauty.

Later variants would claw almost forty thousand feet per minute skyward—numbers that put her in the same rarefied company as the MiG-21 and just below the explosive climbs of the English Electric Lightning. In Swiss trials, Draken’s climb rate beat Dassault’s Mirage III by margins that made foreign evaluators look twice at this odd, tailless Swede.

Which was the point.

If Soviet Tu-16s or Tu-22s ever came through Swedish skies, Draken’s job was to be there first.

By 1960, the Dragon was no longer just a white prototype on a company apron. She wore Swedish Air Force markings and sat on alert in camouflage revetments carved out of forest along stretches of highway.

Bas 60, the dispersal doctrine, had become reality.

On a chilly autumn night, somewhere in southern Sweden, a conscript named Johan adjusted his wool cap, stamped his feet, and blew on his hands. The road strip where he stood was just wide enough for a Draken to land, reinforced concrete disguised as ordinary tarmac until you looked closely.

Trees crowded in on both sides. Camouflage nets hung over small parking bays where aircraft waited, their sharp noses pointed toward painted centerlines.

Johan had grown up in a world where the word “war” meant grainy newsreel footage and his grandfather’s stories. Now it meant early morning alerts and the knowledge that on the other side of the Baltic, men his age wore different uniforms and memorized different slogans.

He checked the fuel line connected to the Draken’s belly, the refueling truck idling behind him, vapor curling from its exhaust. Another conscript, Karin, stood by the trolley of missiles and rockets, breath fogging as she watched the squadron sergeant move between aircraft with a clipboard.

The Dragon they worked on was a J 35D, Mach 2 capable, her double-delta wings bearing the scars of training. Her fuselage had been designed in two halves, forward and aft, bolted together so that if the engine needed changing, the rear section could be unbolted and rolled back, the RM 6 slid out like a cartridge. The outer wing panels could be removed for transport to workshops or tucked into forest hides.

This modularity made engines easier to swap and aircraft easier to hide. It also made the Draken look slightly disjointed if you caught her mid-maintenance, like a lizard whose tail had been removed for inspection.

The radio in the field shelter crackled.

“Alpha flight, scramble.”

The word sliced through the cold like a knife.

Johan yanked the fuel hose away, the quick-release coupling hissing. Karin swung the trolley clear as ground crew pulled chocks. The pilot, who had been sitting in a heated car sipping coffee from a thermos, sprinted across the road, climbed the ladder, and disappeared into the cockpit.

The RM 6 lit with a bark and a rising howl. Exhaust shimmered under the tail, the short double “roller skate” wheels of the tailskid glinting as they extended. The afterburner wasn’t lit yet; the forest didn’t need more fire than necessary.

The Draken rolled onto the straight strip of road and paused.

Then, with a roar, she accelerated, trees blurring to green smudges on either side.

At lift-off, her nose rose, her wings bit the cold air, and she climbed out over the dark sweep of forest toward the open sea.

On the scope of a radar station miles away, a blip moved along a track that hugged the edge of Sweden’s airspace. Another blip—Draken—rose to meet it.

Inside the cockpit, the pilot leveled off, flicked on the radar, and watched the screen bloom with a small, bright echo.

Somewhere ahead, a Soviet bomber crew sat in their own metal tube, watching their own instruments. Maybe it was just a training run. Maybe it was a probe, a test of reaction time. Maybe it was simply another line in an endless Cold War ledger of “incidents.”

Draken’s pilot eased the throttle forward. The afterburner snarled. The Mach meter slid past 1.5.

At a pre-agreed distance, he leveled alongside, a few hundred meters off the bomber’s wingtip.

He could see faces through glass. He imagined they could see him: a sleek, strange fighter with broken-triangle wings and Swedish roundels, keeping pace like a watchful hawk.

He rocked his wings in a slow roll. A courtesy, and a warning.

The bomber crew looked back. One of them, behind thick glass, raised a hand in a brief, almost human wave.

We see you, the gesture said. We know you’re there.

We will not pass unchallenged, the Dragon replied.

After a minute, the bomber turned, sliding away from Swedish airspace. Draken banked, following until the line on the pilot’s map was respected, then turned back toward home.

Base 60 worked. The Dragon had done its job without firing a shot.

That was the kind of war everyone preferred.

Years later, after he retired from SAAB, Erik Bratt would walk through the Swedish Air Force Museum in Linköping, hair white, steps slower but eyes still sharp.

Near the entrance, under carefully positioned lights, sat Lilldraken, paint freshened, engine removed. Visitors looked at the strange little aircraft, sometimes puzzled, often charmed. Few realized how much had hung on that small frame’s shoulders.

Further along, in a larger hall, a full-sized J 35 stood on display, double-delta wings outstretched, nose pointed slightly upward, as if waiting for a scramble order that would never come.

A plaque beside it explained the basics: Mach 2 interceptor. In service through the 1960s and 70s. Exported to Denmark, Finland, Austria.

The text spoke of performance, of speeds and altitudes, of climb rates and radar sets.

It did not speak of the nights in 1949 when a young engineer stared at a blank page and imagined a broken triangle that could solve an impossible equation.

It did not speak of chickens fired at glass, of Ferris-wheel rigs spinning fuel tanks in dimly lit halls, of test pilots hanging on the edge of superstall with their hands on ejection handles.

It did not speak of conscripts in forests, of coffee steam mixing with exhaust fumes, of engines that never flew and designs that died in memoranda.

Erik walked up to the Draken and laid a hand on the cold metal of her leading edge.

He could feel, in memory, the tug of the wing through the air.

“We built you for a war that never came,” he murmured softly in Swedish. “That is the best measure of success we could have.”

If the war had come—if Soviet bombers had crossed Sweden in numbers, if interceptors had risen from forests by the dozen, if missiles and cannon shells had filled the sky—the Draken would have been judged by kills and losses, by wreckage on both sides.

Instead, she was judged by something quieter.

By the fact that for decades, any Soviet planner drawing arrows on a map had to factor in the existence of a fast, unforgiving, homegrown interceptor that would make their bombers fight for every mile.

By the fact that this small neutral country, with fewer people than a major city, could look at its sky and say: we will not leave this to others.

A curator stepped up beside him.

“Bratt, isn’t it?” the younger man asked, recognizing him from old photographs.

Erik nodded.

“She’s beautiful,” the curator said. “People are always surprised that Sweden built something like this. That we didn’t just buy from the Americans or British.”

Erik smiled, a small, tired smile.

“We tried that once,” he said. “They stopped sending when the war moved closer to them. It taught us an expensive lesson.”

He glanced up at Draken’s sharp nose, at the familiar crank of the wing.

“So we built our own.”

The curator hesitated. “Was it worth it?” he asked. “All the effort? The cost? For an aircraft that never fired in anger?”

Erik thought of the cable from Washington in 1940, the empty columns in the delivery ledger. He thought of the day Project 1200 landed on his desk. He remembered the first time he saw a Draken lift from a forest road, tailskid wheels spinning, afterburner flame licking the air.

“Yes,” he said simply. “It was worth it.”

The Cold War ended not with bombers over Stockholm, but with parades and speeches and the uneasy absence of an enemy. The dragons built in Sweden were gradually retired, some scrapped, some sold, some preserved.

In one photograph taken late in Draken’s career, a J 35 sits on a highway strip for an exercise, its nose cone open, radar exposed, young mechanics crawling over it like ants under a gray sky. Somewhere beyond the trees, a truck rumbles by, a reminder that the war this machine prepared for was a ghost that never quite materialized.

That was the whole point.

The SAAB J35 Draken began as a pencil line on a cold night, an answer to a question nobody had ever asked a small neutral country before:

Can you build a supersonic interceptor from scratch, in time, with limited resources, and make it so capable that it helps prevent the very war it was designed to fight?

The answer, decades later, sat in a museum, silent and proud.

Yes.