At midnight on Sunday, 8 September 1968, the Danish naval officer Christian Christiansen writes the weather data in the logbook of the lightship "Gedser Rev": wind SE, 1-2 Bft, air 15 °C, water 17 °C. Its sea position is between Gedser in the south of the island of Falster and the coast of the GDR. "Gedser Rev" is the most important sea mark for navigating the notorious Kadet Channel.
At 4 a.m. sharp, Christiansen goes on deck once again to read the data from the weather station. It is a warm, starry night. The sea is smooth. He sees a single wave rolling towards him from the south. What is that? It disappears just off the side of the lightship. He pays no attention to the strange wave.
That is also interesting:
Suddenly he hears a human voice. In the middle of the Baltic Sea! He runs into the wheelhouse and grabs the binoculars. No other vessel can be seen. Was he mistaken? But then the voice sounds again: "Help, help!" Christiansen sounds the alarm with the ship's bell. A few seconds later, all six crew members are on the scene. They shine a searchlight into the darkness and spot a person. They immediately throw him a line, which the stranger can hold on to.
"Good morning, my name is Bernd Böttger and I come from Sebnitz near Dresden"
Minutes later, the rope ladder is hanging overboard. Christiansen puts on a lifejacket to help the supposed castaway out of the water. But he is already smiling as he climbs up himself - using only one hand because he is holding a strange device in the other.
"Good morning, my name is Bernd Böttger and I come from Sebnitz near Dresden. May I come on board?" asks the stranger in the finest Saxon. Not only that: he is allowed to shower and is given clothes and breakfast. The Danes want to know how he was able to swim so far and what kind of machine it is.
"I didn't swim," replies Bernd. "That's my submarine. I was just hanging on."
Christiansen sends a coded radio message to the naval home defence in Gedser. The GDR navy must not find out about this under any circumstances. At around 10 a.m., a launch comes alongside. Bernd Böttger transfers his "submarine" and enters the Danish mainland an hour and a half later. A newspaper reporter and a television crew are already waiting for him there. Bernd gives interviews and demonstrates his invention.
One day later in Lübeck, Bernd is surrounded by journalists. His "mini-submarine", now called the "Aqua Scooter", and the daring escape story appeared in all the major newspapers. The "Neue Revue" celebrates him with the headline "Under water to freedom - the greatest escape of 1968". He makes public appearances, including on Sender Freies Berlin, and is a guest on the NDR programme "Die Aktuelle Schaubude". He exhibits his "mini-submarine" at the "Arbeitsgemeinschaft 13. August", which runs the escape museum "Haus am Checkpoint Charlie" in West Berlin. At this point, Stasi chief Erich Mielke takes a personal interest in him.
GDR rebel since time immemorial
Bernd Böttger was already a case for GDR state security as a teenager. In the summer of 1958, when Bernd was 17 years old, he had his first three-stage solid-fuel rocket ready to launch high into the sky. On 10 June 1958, in a meadow not far from his hometown of Sebnitz, he ignited the homemade missile. It rises and disappears into the blue sky. Unfortunately, it did not orbit the earth, but landed shortly afterwards in the centre of the courtyard of the Sebnitz district police office.
Having just returned to his basement workshop, Bernd is visited by men in leather coats. He has a cartridge full of black powder in his trouser pocket. While the Stasi men ask him questions in the cellar, he lets the explosives disappear into a pile of briquettes behind his back. His youthfulness protects him from punishment.
After the 8th grade, Bernd Böttger learnt the trade of a skilled chemical worker at the VEB Sächsisches Kunstseidenwerk Pirna. From September 1958, he then worked at VEB Pyrotechnik Silberhütte in Harzgerode. He now also worked with explosives and rockets. The Stasi still had him in their sights. The comrades were told that Bernd knew how to make people fly over obstacles with rocket engines strapped to their backs.
Bernd is inquisitive and inventive. After just one year at the company, he is sent to study directly at Magdeburg Engineering College at the age of 18. After just five semesters, however, he had to leave the technical college without a degree. A Stasi report states that he was expelled "because of negative discussions".
Inventions for the escape from the GDR
Bernd is learning to scuba dive and is experimenting with combustion engines. He owns two Opel cars built in the 1930s and several old motorbikes. In January 1963, he toboggans uphill on his propeller sledge in front of the astonished Sebnitz residents. But in secret, the young inventor is working on a device that will enable him to escape from the GDR.
His godmother from Allensbach on Lake Constance sent him a wetsuit with a bonnet in 1966. Barakuda has been manufacturing these wetsuits for divers since 1954. With a wetsuit, you can stay in the water for hours without your body temperature dropping. Bernd decides to build a "mini-submarine" to which he can attach himself and be towed unnoticed through the Baltic Sea.
He estimates the power required to pull a person under water at 1 kW or 1.5 hp. An electric motor would be easy to seal against water as it does not require an air supply. But there are no batteries that provide enough energy for such high performance over many hours. So he has to build a submersible with a petrol engine.
His favourite was the Hühnerschreck engine, the most popular auxiliary bicycle engine in the GDR from 1954 to 1959. However, because of the mopeds produced later, the Hühnerschreck is no longer manufactured. But Bernd manages to get hold of a second-hand one. Officially, the machine is called the MAW auxiliary engine, named after the manufacturer VEB Messgeräte- und Armaturenwerk in Magdeburg. The 6 kg 1-cylinder two-stroke engine has a displacement of 49.5 cm3 and an output of around 1 kW. It is very simple and built without any technical bells and whistles. This makes the chicken scarer extremely robust. However, it is also very loud, which gave it its name.
Bernd seals water-sensitive parts such as the carburettor, ignition coil and breaker with plastic. He builds a snorkel about one metre long for intake air and exhaust gases. In the summer of 1966, he tries out his development in various lakes in the Sebnitz area. In September 1966, he tested it for the first time in the Baltic Sea near Binz on the island of Rügen. One problem is the snorkel for the intake air: if it undercuts or a wave washes over it, the engine dies. The "submarine" is also very loud; everyone in the neighbourhood immediately hears that there is a chicken scare under water. Bernd is often observed. He no longer makes a secret of it and now even tests his invention in the Sebnitz swimming pool at the start of the 1967 season.
First escape attempt
On 14 June 1967, he travelled to Lake Templin north of Berlin with a tent and a "submarine" in the boot of his car. On the way there, he meets up with his girlfriend, schoolgirl and long-distance swimmer Maja O., in the capital. They agree to flee to the West together.
Bernd has a new neo. In addition to a snorkel, mask and fins, he has brought an old neoprene jacket for Maja that he got from the West back in 1963. He has covered one of Maja's gymnastics trousers with rubberised material to protect her from the cold. He has also made a bonnet. Everything fits perfectly. To be on the safe side, they agree not to contact each other again. On 20 July 1967, they plan to meet at the Baltic Sea. Bernd undertakes test drives on Lake Templin and improves a few details. The fact that it makes such a hellish noise, especially at night, really bothers him. But he can no longer change that.
On 28 June 1967, he travels to Boltenhagen and registers at the Wohlenberger Wiek campsite. Boltenhagen is the last place on the GDR coast that holidaymakers are allowed to visit. The restricted border area begins behind the Redwisch district at the north-western end of Boltenhagen. Bernd is looking for a place to land illegally at night. It's holiday time and there are lots of people on the beach. In his uncomplicated manner, Bernd chats with the soldiers and tries to find out details about the border security. Little does he realise that the Stasi have long had him in their sights.
After 8 pm on 7 July 1967, he takes the bus to the cliffs between Boltenhagen and Redwisch. He walks along the beach and hopes to find a less frequented spot for the secret launch. At 11 p.m. he heads north-west towards the cliffs. Suddenly, two soldiers jump out of the bushes and point their Kalashnikovs at him: "Hands up! You are under arrest!"
Bernd spends three and a half months in custody in Dresden. On 26 September 1967, the Sebnitz district court charged him with "preparing to leave the GDR illegally". During the trial, Bernd denies the charges: He had only constructed his "submarine" in order to revolutionise water rescue in the GDR. As he himself had already worked as a lifeguard in the summer, the argument doesn't sound completely out of thin air and the judge makes a lenient judgement: Bernd receives an eight-month prison sentence, suspended for two years.
His invention is confiscated. However, the wetsuit that is so important to him is returned to him. When Bernd is released, he already has a new and improved diving device in mind. He came up with the entire design in prison. There are no sketches on paper, only in his memory. And this time, nobody will find out about it.
Further development of the "submarine"
As soon as he is released, he begins to put his new ideas into practice. So that the rattling two-stroke engine no longer betrays him, the exhaust gases are not channelled directly to the outside, but first into a fist-sized rubber ball that absorbs the shocks of the piston stroke. From there, they go into the tank, which can therefore only be half full, and on into the next chamber, above which there is a snorkel for sucking in fresh air and a water separator.
Supply air and exhaust gases are therefore channelled through one and the same inlet. There is a slight overpressure in the snorkel when the engine is running, so that any water that may enter is expelled. The overpressure in the air chamber has the side effect that the combustion air is not sucked in but pressed into the engine with slight pressure, which leads to a turbo effect.
The fact that the engine sends some of its exhaust gases back into the combustion chamber does not bother the two-stroke engine. There is only the risk that the spark plug will soot up. For this reason, Bernd constructs the watertight power supply in such a way that he can remove it when the engine is up and unscrew and clean the spark plug. For this purpose, he buys an air mattress that he can inflate at sea as a "work platform". The engine prepared in this way is barely audible under water.
Second attempt
8 September 1968 is a warm late summer's day. Bernd Böttger arrives at the Graal-Müritz campsite east of Rostock-Warnemünde on the Mecklenburg Baltic coast in the afternoon, registers with the campsite warden and immediately sets up his tent. He parks the car near the beach and leaves his equipment in the boot. Then he unobtrusively inspects the beach: although he is a long way from the inner-German land border, the coast is also patrolled - on land and at sea. However, there are no patrols to be seen at the moment.
Even late in the evening, the air is still 18 degrees and the water is 17 degrees. A light south-easterly wind is blowing. The conditions are almost ideal. The only thing he doesn't like is the swell. At 10 p.m. he puts on a jumper and his wetsuit with bonnet over it. He takes his mask, snorkel and fins out of the car, closes the boot lid again and looks around him: the holiday season is already over, not a single holidaymaker is on their way. It's now or never!
Half an hour later, Bernd puts on a six-kilo weight belt and takes his "submarine" out of the boot. In his other hand he has his fins, snorkel and mask. He heads straight for the beach, puts on his fins, goggles and snorkel and wades into the surf. Standing in waist-deep water, he looks around one last time. He will never see this land again. Suddenly he hears voices. A man shouts: "Look, there's still a swim in the water." It's high time! With a turn of the propeller, Bernd starts the engine and hangs behind his invention, which immediately pulls away. Thanks to his lead belt, the team immediately goes to depth. Seconds later, nothing can be seen or heard on the surface.
Alone in the sea
Only after a long time does he dare to surface again to find his bearings. He is alone on the sea at night. The coast of the GDR lies as a flat, dark strip behind him. Only the spotlights of the watchtowers glimmer across the dark surface of the water. Bernd is already so far from the shore that nobody can see him. He looks for the constellation of the Big Dipper and the fivefold extension of its rear axis: that's where the North Star is! Denmark must lie in this direction - and the Danish lightship "Gedser Rev" must be about halfway there. However, he considers it unlikely that he will meet the ship on the long journey across the sea, despite its powerful lantern. He doesn't even know the identification of the "Gedser Rev" light, because nautical charts are not allowed to be sold freely in the GDR.
Bernd estimates the speed at which his "submarine" pulls him at five kilometres per hour. He is in high spirits. He has never been able to test the improved model with its many technical innovations before. But his invention runs like Swiss clockwork. And the motor is extremely quiet.
Around midnight, he hears a loud roar. It's not his two-stroke! He emerges and is startled. A guard boat from the Coastal Border Brigade, which is subordinate to the People's Navy, is heading towards him! His first thought: They've spotted him! Have they come to arrest him? Or do they want to drag him through the propellers? Or are they "mercifully" just going to shoot him? Bernd sees the grey prow just a few metres ahead of him. He quickly switches off his engine, exhales deeply and lets himself sink into the depths thanks to his lead belt and his heavy "submarine". He can hear the ship's diesel engines just above him. He knows that he can hold his breath longer than the doctors advise.
Almost there
He has to get back up, otherwise he will die. But his strength is no longer enough. He throws off the weight belt and dashes upwards. All he can see of the guard boat is the stern. He takes several deep breaths. Will his engine start again? He turns the propeller with all his might and his "submarine" comes back to life. This also gives him wings. Now that he no longer has a lead belt, he lets himself be pulled through the Baltic Sea just below the surface and pushes a small wave in front of him.
Something jumps out of the water in front of him. A cod the size he has never seen before. Bernd is in high spirits. His engine purrs without interruption. He has no watch. On the eastern horizon, the light seems to be getting brighter and redder. Could this be a harbinger of sunrise? But the sun doesn't rise until around 6.30 am. Bernd has never been out on the open sea at night.
He sees lights in front of him. They flash red and green in different rhythms. Are they fairway buoys? A white light flashes above everything, which appears to be much brighter. Is that Denmark already? His "submarine" pulls him onwards through the now smooth sea. Bernd keeps an eye out with his head above water. The flashing white light is already very close. He eases off the throttle and steers towards the stern of the strange ship. A large red flag with a white cross is waving in the light southerly wind. At the stern, he reads the home port "Copenhagen". Bernd switches off the engine and calls out "Hello". Nobody answers. Now he shouts as loud as he can: "Help, help!" A spotlight flares up on board. He is saved.
West reached, career launched
In West Germany, Bernd Böttger is celebrated as the refugee of the year 1968. He is 28 years young, good-looking, athletically trained and always in a good mood. Above all, he is a creative inventor. He doesn't believe in nicotine, alcohol or drugs. Instead, he drinks tea made from herbs he collects himself. Beautiful women lie at his feet. He cares little. Several companies offer him work. Bernd believes that he can now lead a free and self-determined life. He has no idea that the Stasi has him in its sights in the West too.
The company Babcock & Wilcox in Oberhausen, which develops technical systems for energy generation and places great value on its employees' thirst for research, offers him the opportunity to develop his "submarine" to series maturity. Bernd is delighted and moves to Annabergstraße in Oberhausen in January 1969. In June, he is seen at the German Underwater Research Station BAH II, which operates a diving station in Lake Constance. Finally, on 15 September 1969, his Babcock scooter, which had been developed to series maturity, was presented to the public. He is granted three international patents.
The successful inventor proudly tells his mother in Sebnitz about his new life in letters. But she is worried. She and her sons Horst and Achim had already been picked up and interrogated by the State Security. Neighbours and acquaintances were also questioned. Worried that their mail might be monitored, they sometimes correspond using the addresses of relatives. The mother received a visit from a businessman from Sebnitz. He says that he is allowed to travel to the West on business and offers to take her mail with him so that he can pocket it "over there" or even deliver it personally. The mother gratefully accepts. She has no idea that the helpful stranger also works for the Stasi.
Development of the Aqua Scooter and military variants
A few weeks after the presentation of his scooter, Bernd's time at Babcock & Wilcox comes to an end. ILO-Werke in Pinneberg near Hamburg, which belongs to the American Rockwell Group, wants Bernd Böttger and the rights to his invention and the patents. They offer him his own research department, a monthly salary of DM 1800 and additional royalties of DM 200,000 in the first year for his patents. The income from the patents is expected to increase to around DM 1.2 million over the next three years.
Bernd is floating in happiness. He moves to Pinneberg to Mrs Braun's boarding house in Stettiner Strasse and works in his own research department at the ILO works. The company produces a wide range of specialised engines - from lawnmower engines to torpedo drives. ILO makes its biggest turnover as a manufacturer of moped engines for several West German companies. Bernd has a wide range of 2-stroke petrol engines at his disposal. ILO also produces special engines for the American military.
Bernd is commissioned to develop a military version for the U.S. Navy's combat swimmers in addition to the civilian Aqua Scooter for diving. Everything is top secret. Bernd's research department is hermetically sealed within the factory. The military Aqua Scooter should be powerful and be able to travel silently under water at speeds of up to 15 kilometres per hour.
Stasi targets Böttger again
This did not go unnoticed by the HVA, the "Main Administration for Reconnaissance", which was responsible for foreign espionage at the Ministry for State Security. A file was opened with the name "Diver" and as much information about Böttger's life as possible was collected. The GDR secret service found out that he owned a car and a rubber dinghy and spent his weekends at the North Sea or Baltic Sea trying out his diving equipment. He is a loner. Sometimes he travels to France or Spain to test his scooters, which are now available in different versions, in the Mediterranean. Does the Stasi want to bring Bernd back to put his invention at the service of socialism? Are the military of the Warsaw Pact interested? Or do they want to liquidate Bernd?
Bernd saves all the money to buy a sailing yacht and sail around the world. In a letter to his mother dated 12 August 1971, he writes: "I've had a new room-mate since Sunday. He is from Dresden and left about 4 weeks ago via Hungary - Yugoslavia - Austria. He's a great mate. But the remarkable thing is that his father is already visiting here from over there."
Bernd is naive and thinks little of his new neighbour Erich Wolfgang K. Bernd also has new friends on the Mediterranean: they live in Perpignan in the south of France, just before the Spanish border. Bernd visits them there on Saturday 26 August 1972. They arrange to meet the next day to go diving in Cala Joncols, which is already on the Spanish side. Bernd drives his car to the popular cove the evening before, where he spends the night in a tent.
On Sunday morning, Jean Paul B., his wife Jaqueline and his brother-in-law take their motorboat "Norfeu", which is moored in the harbour of the Spanish town of Rosas, to visit Bernd in Cala Joncols. They meet at around 10.30 am. Bernd goes on board the "Norfeu".
Mysterious death
27 August 1972 is a beautiful, sunny Sunday. There are already a lot of anchormen on site in the morning. The new friends sail together with Bernd on the "Norfeu" to the narrow rocky bays a few hundred metres to the east. There is a lot of laughter on board.
At around 11 a.m., Bernd jumps into the water with a snorkel, mask, fins and his homemade harpoon to hunt for something for breakfast. Jean Paul B. then puts on his diving equipment with compressed air cylinder and also goes to depth. At 11.30 am, Jean Paul comes up to the surface and screams for help. Bernd is lying motionless on a rock at a depth of eleven metres. He brings him to the surface himself. They call for a faster motorboat and race to the nearest doctor in the harbour town of Rosas, six nautical miles away. The Spanish doctor, Dr Pereira, can only determine that he is dead. At the later autopsy, "suffocation" is recorded as the cause of death.
One day later, his room-mate disappears head over heels from the boarding house in Pinneberg. Bernd's mother asks for permission to travel to the West to say goodbye to her dead son. Although she is already a pensioner, the Stasi refuses. Instead, Bernd's ashes are sent to her.
After reunification, Bernd's younger brother Achim Böttger tried to solve the mysterious death of the "fugitive from the republic". In 1993, he filed a criminal complaint with the ZERV (Central Investigation Centre for Government and Association Crime) on suspicion of murder by the State Security. The witnesses who saw Bernd immediately before and after his death are still living in Perpignan. But nobody bothers to investigate the crime scene. Instead, the ZERV officers could think of nothing more than to ask the former head of the Stasi in Sebnitz whether there had been an intention to murder Bernd Böttger in the West. He denies it.
In October 1995, the Berlin public prosecutor's office wrote to Achim Böttger that "no promising investigation approaches are apparent" and that the proceedings would therefore be discontinued. Achim Böttger has not given up hope that at some point a witness or a document from the Stasi archives will provide information about the circumstances under which his brother died - and why.
Legacy continues
Bernd Böttger's invention lives on: the civilian Aqua Scooter is built in series at the ILO factories. The 2-stroke engine used has a displacement of 48 cm3 and develops an output of 2 hp at 4000 rpm. The more powerful military version can be seen in James Bond films. How many Aqua Scooters were produced for the U.S. Navy remains a secret. They were first used in combat in October 1973 during the Yom Kippur War, when Israeli combat swimmers used them to cross the Suez Canal.
At the end of 1990, the ILO factory closed its doors for good. The Aqua Scooter with combustion engine continued to be manufactured in Italy for a long time. Today, batteries are so powerful that its modern successors are powered by electric motors. They have become a popular leisure device. Few people know that their inventor came from Saxony - and fled to freedom with them.
