Aquariums & Specialty glazing
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Passion for the deep sea

© Stiftung Rebikoff-Niggeler

Kirsten and Joachim Jakobsen are completely at home under water: Equipped with a viewing dome made of PLEXIGLAS®, the married couple explores the deep sea and its inhabitants in the LULA1000 submersible.

Joachim Jakobsen started diving when he was just five years old. Today, he and his wife Kirsten explore the deep sea. Since 2013, the couple have been looking for the legendary giant squid. However, they have not yet found the Architeuthis. The previous lack of success has not put the researchers off their quest though. On the contrary, they want to track down the underwater giant with the help of a new strategy. In the following interview, the Jakobsens explain what their exact plan is and how the only way to succeed depends on the LULA1000 with PLEXIGLAS® viewing dome.

Researchers with a passion

© Christoph Bauer / Röhm GmbH

The Jakobsens have been exploring the underwater world together for many years. They are on the lookout for lost submarines and deep sea creatures. In 1994, the couple founded the Rebikoff-Niggeler Foundation non-profit organization on the island of Faial in the Azores. This organization helps them continue the work of the underwater pioneers, Dimitri Rebikoff and Ada Rebifkoff-Niggeler. In order to better understand the habitat of the deep sea, the couple take their LULA1000 submersible to depths of up to 1,000 meters.


Mr. Jakobsen, when did you have the idea to build a submersible?

Joachim Jakobsen: I know it sounds strange but, as a young boy, I was on a trip with my parents through the Eifel and I saw a slurry tanker, which is basically a pressurized container with an entry on the top. And I thought to myself, if you put a PLEXIGLAS® window on the front of that, it could be a submersible!

An ambitious plan for a young child.

Joachim Jakobsen: I grew up around submersibles. My father worked for the diving pioneers Dimitri Rebikoff and Ada Rebifkoff-Niggeler. Diving was part of daily life. I got my first piece of diving equipment when I was five and I used it to look for Easter eggs underwater.

There’s quite a jump between diving for Easter eggs and deep sea diving.

Joachim Jakobsen: True. But there was a step in between. Before LULA1000 came LULA500. It had a different concept, using a diesel engine for propulsion above water. However, it had a viewing dome which didn’t meet our requirements and was only good for diving to depths of 500 meters. It soon became clear that LULA1000 had to have a dome made of highly transparent and extremely strong PLEXIGLAS®.

So, in 2010, you approached Röhm with your idea. How did the manufacturer of the brand acrylic glass react to your request?

Joachim Jakobsen: At first, they were astonished. The thick, perfect blocks have been produced in Weiterstadt for a quite some time. But forming a viewing dome shape from PLEXIGLAS® was unknown territory for the company. Wolfgang Stuber was my contact and he recommended I look for an alternative, just in case. But I was stubborn. I wanted PLEXIGLAS® to fulfill our high optical requirements and nothing else.

A distortion-free view

The viewing dome on the predecessor, LULA500, did not satisfy the requirements of the researchers. They therefore decided to use the brand acrylic glass from Röhm for the viewing dome on the successor, the LULA1000.

© Christoph Bauer / Röhm GmbH

The LULA1000

It was not just the viewing dome which was specially developed for searching for the giant squid, so was the entire submersible. The LULA1000 is 7.5 meters long, 1.65 meters wide and 2.65 meters high. Three people can fit inside the LULA1000. Its maximal diving depth is 1,000 meters.

© Dave Mothershaw / Röhm GmbH

The researchers

Joachim Jakobsen is in charge of controlling the submersible during diving operations.

© Christoph Bauer / Röhm GmbH

The researchers

Kirsten Jakobsen is in charge of filming and logging the navigation data. This enables all the collected data and images to be linked to the respective positional and depth data, thus displaying exactly where the data was collected.

© Christoph Bauer / Röhm GmbH

Mrs. Jakobsen, you are the camerawoman of the deep sea. Has your husband’s persistence paid off?

Kirsten Jakobsen: Absolutely! The first time we dived in the LULA1000, we saw the viewing dome disappear in front of our eyes and our camera – an amazing effect. It just simply disappears! Almost all of our guests have asked if they can touch the dome, just to check if it is still there.

But you haven’t yet been able to film the giant squid?

Kirsten Jakobsen: Unfortunately no, but we will. Filming animals requires patience and perfect equipment to be ready when the time comes. We have filmed many, many other animals underwater though, including minuscule creatures, whose images are also razor-sharp thanks to the clarity afforded to us by the dome.

Joachim Jakobsen: And this is exactly what excites the scientists who dive with us so much. They are only a few meters away from animals in their natural environment which they would otherwise only be able to see dead in their laboratories, if at all.

Fascinating world underwater

The researchers have not yet been able to find the giant squid, but they have been able to observe this smaller specimen and many other animals.

© Stiftung Rebikoff-Niggeler

Fascinating world underwater

Thanks to the PLEXIGLAS® viewing dome in the LULA1000, even minuscule animals can be seen razor-sharp…

© Stiftung Rebikoff-Niggeler

Fascinating world underwater

… while other marine creatures were spotted too, like this sixgill shark.

© Stiftung Rebikoff-Niggeler

An extraordinary find

The Jakobsens made a sensational discovery when they found the missing U 581 submarine from World War II. The 67-meter-long and almost 800-ton submarine was found off the coast of the Pico island in the Azores at a depth of 870 meters.

© Stiftung Rebikoff-Niggeler

You also found a lost submarine. Are you still looking for the giant squid?

Kirsten Jakobsen: Definitely. We are now working together with a team of German scientists who specialize in whales. For the first time, we will be spending several days at sea with our submersible carrier and the LULA1000.

Why whales?

Joachim Jakobsen: Squids are a sperm whale’s favorite food. And their absolute favorite is the giant squid. We want to use the hunting ability of this giant to get closer to our goal of filming an Architeuthis.

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