Life on the Vidda remained harsh. Of the Vemork saboteurs who had stayed behind, only two, Bonzo Haukelid and Einar Skinnarland, remained. The others had been driven away by the weather, starvation, the German Razzia, or had returned to Britain for further specialist training.
It was 14 February 1944 when Haukelid skied towards Rjukan, at Wilson’s behest and on a top-priority mission. Much had happened over the intervening months since Operation Gunnerside had scored such signal success. Niels Bohr had finally seen the light, and not a moment too soon. In the summer of 1943 the Nazi regime had finally shown its true colours in Denmark: Jews and other enemies of the Reich were rounded up and carted off to the concentration camps.
No longer could Niels Bohr—the grandfather of atomic physics—bury his head in the proverbial sand. He had been wrong about the Nazis and Hitler; they were far from being a benign presence in Denmark. In September 1943, just before the Gestapo came for him, Bohr fled Copenhagen for neighbouring Sweden.
When he reached Stockholm he appealed to Princess Ingeborg, the sister to the Danish King Christian, to save Denmark’s Jews by making a royal appeal to the German leader’s ‘better instincts’. Secretly, Princess Ingeborg was part of Stephenson’s spy network, and she was a tough and plain-speaking woman.
‘You are out of touch with reality,’ she told Bohr, bluntly. ‘You lived in the Third Reich, but you never understood it.’
Bohr tried to protest. ‘But surely an appeal to Hitler—’
Princess Ingeborg rounded on him. ‘Dear God! An appeal to Hitler is an appeal to the Devil himself. If we draw attention to those Jews, Hitler could kill every one of them … Your laboratory has been a fool’s paradise.’
The Princess’s words cut through the fog of Bohr’s delusions. Seeing the Nazi regime for what it was, he agreed that the only course of action left open to him was to travel to Britain and join forces with the Allies. In spite of his naivety and his misguided loyalties, he was wanted on the Manhattan Project badly. If Bohr would cooperate, he could help win the nuclear race for the Allies.
The Allies’ need for Bohr was too urgent to countenance a lengthy sea voyage. So it was that a Mosquito aircraft took off from RAF Tempsford—Gibraltar Farm—scheduled for a midnight rendezvous with the Danish scientist on a remote and deserted Swedish airstrip. The Mosquitoes executing the moon flights had been converted so that the bomb bay could carry one passenger, slotted in and breathing on oxygen.
‘SOE had priority as far as the allotment of seats … was concerned,’ Wilson remarked, of these flights. ‘It was possible to send in a limited number of men to make their way into Eastern Norway, and more important, to bring out many … such as Professor Niels Bohr, the nuclear physicist, travelling in the bomb rack.’
Bohr almost didn’t survive the nerve-racking journey.
On a deserted airstrip the wooden-framed aircraft awaited, its engines still turning. From the bowels of the Mosquito had climbed a mysterious young woman, an SOE agent on a secret assignment. She briefed the Danish scientist hurriedly, leaving little to the imagination: he would be isolated from the Mosquito’s aircrew for the duration of the return journey to Britain, and if the unarmed aircraft were attacked he could expect little help.
If he were wounded, there were morphine and medicines packed into a small, hand-held kit. He would need to medicate himself and to hang on until arrival in Britain. The converted bomb bay would allow little room to move. If the plane went down in the icy waters of the North Sea he would be trapped, but at least, like the aircrew, his suffering would be short, before death from exposure.
Her briefing delivered, the young woman peeled off her snow-suit—designed to keep a human warm at high altitude—and handed it to the world’s pre-eminent nuclear physicist. It was 7 October 1943, and Bohr had just turned fifty-eight. Taking her helmet and mask—still warm from her body heat—he clambered into the dark and constricting hold. Moments later the bomb doors hissed closed, the twin Rolls-Royce Merlin engines snarled and Bohr was whisked into the dark skies.
As they climbed to altitude the pilot checked the airflow to his mystery passenger, but the dial was stuck stubbornly on zero. Either it was faulty, or the man in the hold wasn’t breathing any oxygen. The Mosquito’s only protection against enemy fighters was speed and altitude, but if his passenger wasn’t getting any oxygen and they remained at this height, he would die.
The pilot had no option but to push his nose downwards and dive towards the sea. He recalculated his route. If he turned further north he had just enough fuel to make Scotland at full speed. Probably. He would need to juggle throttle and speed with the remaning fuel supplies, to nurse them into an airfield like Wick.
When the Mosquito finally touched down it was sipping on fumes. An ambulance tore across the tarmac. The bomb bay whispered open to reveal an unconscious Niels Bohr. Waiting on the runway was Stephenson himself. Bohr had a weak pulse, but at least he was alive. Somehow, the oxygen supply had failed.
In due course Bohr was nursed back to good health. Some days later he was in London, being visited by the great and the good of the British nuclear initiative.
‘Professor Bohr was a gentle soul,’ Stephenson remarked. ‘He genuinely believed in Gandhi’s philosophy of opposing evil with humility, of resisting violence with intellectual weapons. He had to come out of Nazi surroundings to comprehend the scale of the wickedness we were dealing with.’
A few days later Bohr met Churchill. He was bombarded with queries about Hitler’s plans to shower London with thousands of Vergeltung (vengeance) weapons. Could an atomic or radiological warhead be fitted to such rocketry, as the Allies feared? Had the Nazis mastered such technology? Bohr couldn’t answer. Ensconced within the ivory tower of his Copenhagen laboratory, he hadn’t even known about the Third Reich’s development of the V1 and V2 technologies. Yet here in Britain expert teams equipped with radiation detectors were set to deploy on the city streets, in case the Vergeltung weapons rained down such an apocalypse.
Churchill did little to hide his frustration. He scolded Bohr’s passive and unwitting collaboration with the enemy, not to mention his wilful ignorance about the true nature of Hitler’s ideology. He had been cosseted and stroked by the Nazis, and he had chosen to believe in their hollow words and flattery. Bohr was told that he was needed in the US as soon as possible to help perfect the Allied bomb.
‘We cannot fight one barbarism with another barbarism,’ he objected.
‘We won’t survive to fight for anything if we neglect this new weapon,’ came the counter-argument. ‘The freedom to behave in a civilised manner must be defended, and sometimes that means using violence.’
Bohr was persuaded to fly to America. He would go there to work on the Manhattan Project under an assumed identity—travelling as a ‘Mr Baker’. Reluctantly, and after a long campaign to enlighten him, Bohr had become another of the Baker Street Irregulars.
As Bohr flew west to the USA, so a US Air Force armada thundered eastwards, darkening Norway’s skies. It was 16 November 1943, and in the nine months since Operation Gunnerside the Germans had moved heaven and earth to get the SH200 production up and running again. Their success in doing so, and the transformation of the Vemork works into an utterly impregnable fortress, had convinced the Allies that only an air raid could stop them now.
General Groves had got his way, and a USAAF bombing raid was put into operation. The armada of 460 bombers—Flying Fortresses and Liberators—included some executing diversionary raids, while the main body headed for Vemork. At around 11.30 a.m.—when most of the workers should have broken for lunch, thus lowering the risk of casualties—the lead aircraft opened their bomb doors. Over the next thirty minutes hundreds of 500-pound bombs fell in and around Vemork.
Direct hits were scored on the railway along which the Gunner-side force had made their clandestine approach, on the pipelines snaking down the mountainside, and on the suspension bridge that spanned the gorge. Four bombs struck the heavy water building itself, but with the SH200 plant secreted in the basement, they did little or no damage to the key infrastructure. The all-important high-concentration cells were not even touched.
Due to a navigational error, dozens of bombs were dropped on the fertilizer plant at Rjukan. In total, twenty-two civilians were killed in the air raid, which enraged the Norwegian government in exile. They had not been informed that an air attack was scheduled to take place. They complained that the raid was ‘out of all proportion to the objective sought’, especially as not a single drop of SH200 had been destroyed.
With Haugland having left the Hardangervidda, Einar Skinnarland remained Wilson’s sole communications link on the ground. In contrast to his own government’s bitter complaints, Skinnarland sounded a positive note on the USAAF raid: ‘Great enthusiasm for the results of the attack and for the accuracy … All pipelines for about 100 metres … badly damaged … Suspension bridge fell down and the gas pipes and electric cable to Rjukan are broken …’
Certainly, the USAAF attack did achieve one concrete result in the battle to defeat the Nazi bomb: it convinced the Germans that continued attempts at SH200 production in Norway were futile. They didn’t possess the fighter aircraft to defend the Vemork plant should a second and more accurate bombing raid be launched. Thus the decision was taken to remove both the SH200 stocks and the means to produce them to the comparative safety of the Fatherland.
Skinnarland alerted London to the Nazis’ intentions. Wilson read his message with growing unease.
Recently, the Allies had secured air reconnaissance photos of the Haigerloch-Hechigen area of southern Germany. These revealed that structures were under construction that had all the appearances of nuclear reactors. With Berlin increasingly being targeted by Allied bombing raids, this was the area into which the Uranverein were known to have retreated with their precious uranium pile.
In their intelligence assessments the Allies were working on the assumption that the Germans had a 100-kilowatt reactor up and running, which would produce enough ‘fission products’ to ‘manufacture 4-8 bombs in a year’. The fear was that the Reich would either develop a fully fledged nuclear arsenal, or in desperation strike quickly by showering its enemies with some kind of radioactive warhead. The race for nuclear supremacy had become a brutal ‘war of nerves’, in which both sides were largely in the dark regarding the other’s capabilities.
‘One or more research institutes have been set up in the neighbourhood of Hechigen …’ Allied intelligence reports concluded. ‘Heisenberg is known to be working there … Information has also been received that Hechigen and the neighbourhood district are “prohibited areas” under military control … Heisenberg was in charge of experimental work on the production of a U.235 bomb … he was stated to have half a tonne of heavy water, and to be due to receive a further tonne.’
If Vemork’s SH200 could be married up to the Uranverein’s new Haigerloch-Hechigen facilities, it could prove disastrous. At all costs, its shipment to Germany had to be stopped. Hence Knut ‘Bonzo’ Haukelid’s February 1944 foray into Rjukan—a lone figure moving south on skis, and with sabotage in mind.
Haukelid remained the only fully trained SOE agent in the region who was in a position to act—a reluctant Einar Skinnarland being charged with maintaining the all-important radio communications link with London. But from the very start Haukelid had questioned the merits of mounting any fresh sabotage attempt.
After Gunnerside, all the windows and doors into the SH200 plant had been bricked up, leaving just the one entranceway, which was heavily guarded at all times. A battalion of commandos would have trouble fighting their way in there, and Haukelid was alone—apart from a handful of locals recruited at short notice.
He had other reasons to feel daunted and dispirited: this war had cost him dearly. Recently he’d received a letter from his young wife, Bodil, asking for a divorce. Their wedding earlier in the war had been a rushed affair, after which Haukelid had disappeared to fight. Bodil was in Sweden and too much time and distance lay between them. She was seeing another man, she told him. Haukelid had given so much to the struggle. He’d fought for survival for eighteen months on the Vidda. His mother had been arrested, and his father was still in Gestapo custody facing untold horrors. His friends had been tortured and killed.
And now this: his wife of a few short years was leaving him.
Haukelid’s mood was dark. On Gunnerside, he’d been part of a well-trained, well-armed, ultra professional outfit. Now he was alone, apart from one or two local resistance men, and the Germans were on the very highest state of alert. He rated his chances of survival at about zero, and either way he was sure to have the blood of locals on his hands, for the Germans were bound to react with untold savagery.
He’d radioed such misgivings to Wilson. Even if the SH200 stocks could somehow be destroyed, which he very much doubted, the risk of local reprisals was too great. The residents of Rjukan had been warned that if there were to be another sabotage attempt, they would reap the whirlwind. As Haukelid made clear, he did not want to be the author of that storm.
Wilson was under intense pressure from Churchill and Roosevelt; the British prime minister had made it clear that the SH200 shipment had to be stopped, and at all costs. His response to Haukelid was uncompromising, and it brooked no dissent. ‘Case considered. Very urgent that heavy water be destroyed. Hope this can be done without too serious consequences. Send our best wishes for good luck in the work. Greetings.’
Despite Haukelid’s clear misgivings, Wilson kept the faith. He reckoned that one such man in the Vidda was worth a hundred regular soldiers elsewhere. Somehow, Haukelid would find a way.
For his part, Haukelid had spent long enough in London to grow fond of the great city. He’d been drawn to its unique charms, not to mention the bulldog spirit of its wartime residents during the Blitz. If the Nazis succeeded in building their bomb, nothing the Luftwaffe had ever done to destroy London would equal the cataclysm that would follow. He had no choice but to act.
Using his local contacts at the plant, Haukelid studied how the Germans intended to move the stocks of heavy water. Steel drums were to be loaded aboard railway cars, to be shipped along the railway to Rjukan town and onwards to a ferry. The ferry boat would steam across the nearby Lake Tinnsjo, taking the drums by stages to a seaport, from where they would be shipped onwards to Germany.
At all stages General von Falkenhorst’s exhortation—When you have a chest of jewels like this, you plant yourself on the lid with a weapon in your hand!—was to be adhered to. A crack unit of German troops would shadow the SH200 shipment every step of the way. Spotter planes would fly searches above the Vidda, keeping eyes out for suspicious movement or ski tracks, and Gestapo agents had flooded Rjukan town.
Even so, Haukelid sought out the enemy’s weak point. Eventually he figured he’d found it in the Norsk Hydro ferry, the vessel scheduled to carry the drums of SH200 across Lake Tinnsjo. He reckoned the SF Hydro—a flat-bottomed ugly duckling of a boat—was the one chink in the Nazis’ armour.
The SF Hydro was an ancient-looking, steam-powered vessel with a pair of vertical funnels set amidships. A rail car ferry, she was used primarily to shuttle goods to and from the Vemork and Rjukan works. Launched in 1914, and with a weight just short of 500 tonnes, she was already pushing thirty years old. With parallel tracks laid across her flat deck she could carry a total of twelve rail cars, plus 120 passengers.
Haukelid felt certain that the elite German troops charged to guard the SH200 shipment would do von Falkenhorst’s bidding to the letter: they would sit atop the crown jewels—the precious barrels of heavy water—all the way. But paradoxically, that was both their greatest strength and also their greatest weakness.
The day the SH200 barrels were loaded aboard her the SF Hydro was sure to be crawling with German troops, but that didn’t render her immune to sabotage. Far from it.
He just needed the means to execute the kind of attack that he had in mind.