People & Culture

Covenant with mystery: James Cameron’s magic submarine

Dr. Joe MacInnis discusses his relationship with explorer and filmmaker James Cameron as well as how the DEEPSEA CHALLENGER came to be 

  • Published Jun 23, 2023
  • Updated Jul 11
  • 1,532 words
  • 7 minutes
The DEEPSEA CHALLENGER was built in Sydney, Australia, by a group of individuals from England, America, Canada and Australia. (Photo: Mark Thiessen/National Geographic)
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On March 26, 2012, undersea explorer and Academy Award-winning filmmaker James Cameron dove his DEEPSEA CHALLENGER science platform to a depth of 10,908 metres in the Mariana Trench and became the first solo pilot to reach the deepest place in the ocean.

There is magic in his machine. In how she was conceived and built. In her life-and-depth journey. In how she informs and inspires us. DEEPSEA CHALLENGER is more than a machine; she is a fusion of art, science, engineering and discovery. She is a call to action.

How do I know this? I witnessed her almost 50-year journey. I worked on deep-sea expeditions with the man who created her.

James Cameron exits the DEEPSEA CHALLENGER after a successful dive. (Photo: Mark Thiessen/National Geographic)
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James Cameron's sketch of Sublimnos when visiting the ROM at 14 years old. (Photo courtesy Kim Butts)
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My first encounter with Cameron was in 1969. My undersea station, Sublimnos, was being exhibited outside the main entrance of the Royal Ontario Museum in Toronto. On a February morning, 14-year old Cameron got out of a car and headed into the museum. He stopped in front of Sublimnos and made a sketch. This is the station. This is the sketch. There are hints of genius in its detail and perspective.

That night, Cameron wrote me a letter asking for the blueprints. He wanted to build his own station. There was passion in the words and how they were written. I wrote back and encouraged him to move forward with his project. He built a model, put a mouse inside the living chamber and lowered it into the river near his home. This is the model. This is young Cameron launching the model into the river. The mouse survived.

Cameron grew up when Mercury astronauts were starting to orbit the earth and Jacques Cousteau was beginning to build undersea stations. He was inspired when the US Navy deployed a manned vehicle more than 10,000 metres into the Mariana Trench. He aimed his life at the grand adventure of deep-sea exploration.

In 2001 Jim went back to Titanic to produce a documentary feature. The next year, he explored the battleship Bismarck at a depth of 4,900 metres. He had logged more than 3,000 hours underwater and made 75 submersible dives to depths greater than 4,000 metres. Soon after, he told me he was committed to creating a research sub that could go to full ocean depth.

Our undersea lives came together again in 1992. As the co-leader of the Imax-Titanic expedition, I invited Jim to the world premiere of our Imax documentary. He saw the giant ship on a giant screen. He met the Russian sub pilots who carried our cameras and lights. Three years later, during the production of Titanic, he used their expertise to make 12 dives to film the wreck. Twenty-six years after his promise to himself, he was a leader in the grand adventure of deep-sea exploration.

He spent 10 years making sketches, creating CAD drawings, talking to experts, making revisions and building a team. When I visited him on the Avatar 1 set in L.A., all we talked about was the progress being made with his new sub.

Seven metres long, DEEPSEA CHALLENGER was a marvel of linked computers and microprocessors. When you saw her, you knew that something weird and exceptional was going to happen.

James Cameron at 14 with a model he built that was inspired by the Sublimnos underwater habitat.
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DEEPSEA CHALLENGER was built in in Sydney, Australia. Seven metres long, she was a marvel of linked computers and microprocessors. When you saw her, you knew that something weird and exceptional was going to happen.

DEEPSEA CHALLENGER was built by a small, group of brilliant misfits from England, America, Canada and Australia. We spent 60 days together on a ship in the Western Pacific.

Our first dive was to one metre. We made 13 test dives to 20, 1,000, 4,000, 8,000 and 11,000 metres. With an untested sub, an untested team and a malevolent ocean, every descent contained a large measure of dread. This once-in-a-century project had echoes of the Wright Brother’s first flight and the initial ascent of Mount Everest.

On the day of Jim’s 10,908 metre dive, I was in the communications room on the ship’s bridge. We were using audio instruments to track the sub’s free fall toward the centre of the earth.

Jim was jammed into the combat confines of the pilot sphere making forty decisions a minute about speed, depth, direction, power supply, oxygen supply and thrusters. He was using joysticks to control the sub’s functions.

I was holding my breath. At 10,908 metres the compression on the pilot sphere was equivalent to the weight of 26 space shuttles—eight tons per square inch—two SUVs pressing on your thumbnail. A thru-hull failure meant a thunderous explosion and Jim would vanish. Slowly, methodically, he took pictures and recovered samples. On the outer edge of the known world, he was the loneliest person on the planet.

The first dive the DEEPSEA CHALLENGER made was to one metre followed by 13 other test dives up to 11,000 metres. (Photo: Mark Thiessen)
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The place was so stark it was invigorating. The cold and darkness trembled with life. Jim had a profound awareness of his mortal self. He was never more alive than deep inside the ocean face-to-face with the possibility of his own death. His focus was on extreme-place exploration, extreme-image filmmaking and extreme-depth science.

There was a moment when he stopped what he was doing, leaned into the view port, looked at the new-found-land and reflected on his journey. “I felt the full weight and age of the ocean,” he told me.

The explorer married to mystery was gathering insights and emotions to channel into his Avatar 2 movie. He was recommitting himself to diminishing stresses on the ocean and healing the planet.

After three hours, his thrusters started to fail. He decided it was time to go up. He released the ballast and the sub started to rise. It took 70 minutes to reach the sunlight.

The expedition succeeded because we had a transformative leader. Jim changed us and we changed him. We were inspired by a man who for ten long years invested his mind, his money and his mortality in things he believes in. Science-driven exploration. Fail-safe engineering. Healing the planet. During those 60 days at sea, he took us beyond collaboration into a symphony of selves—the performance zone I call team genius. 

James Cameron Into the Abyss


Our planet is over 70 per cent water — primarily ocean water — yet we know more about the surface of the moon than we do the ocean. Explore the DEEPSEA CHALLENGER and dive into the future of ocean conservation. On display from June 5 to Sept. 1, 2023. 50 Sussex Drive, Ottawa. Alex Trebek Theatre. 

James Cameron giving thumbs up after the hatch is opened after his successful dive to 11,000 metres in the DEEPSEA CHALLENGER. (Photo: Mark Thiessen)
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For 60 days I wrote a daily blog for the National Geographic website. As it unfolded, the expedition attracted a global audience, garnering 45 million pieces of print and online journalism and 2.8 billion views of online material. It’s not often you get a chance to look into the soul of a man and the heart of his team. For three months, I had the honour to do both.

You can sum Jim up in three words: Exploration is destiny. He’s an alpha leader with a fierce love for his team. He knows that breakthrough ideas about engineering and exploration are embedded with false starts, improvisations and tight interactions with talented people. Each day, under Jim’s leadership, we made hundreds of decisions about how to fix the sub or get it safely into and out of the water. Any problem was everyone’s problem. With clarity and calmness, he guided us through hundreds of life-and-death judgments.

We saw him carrying the whole project on his shoulders: the financial burden, the engineering options, the scientific objectives, the risk management. He moved seamlessly from role to role. One moment he was the expedition leader, next the sub pilot, then the scientist. He knew when to listen. He knew when to ask questions. He admitted his mistakes. Week after week, we witnessed the peak performance of a multi-systems thinker.

He is not perfect. He thrives on overload and loves to redline his mind with hard challenges for months at a time. Sometimes he forgets that his overload is someone else’s burnout.

One of the many sketches made by James Cameron over a 10-year period as Deepsea Challenger took shape.
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Fifty-four years ago, sea-space pioneers carrying the ancient fire of exploration and discovery inspired a 14-year old boy. In gratitude, James Cameron blazed his own unique trail of science, art, engineering and story telling. His personal fire, including curiosity, creativity and courage, informs his movies, his deep-sea exploration and his Avatar Alliance Foundation.

DEEPSEA CHALLENGER, a co-mingling of cold steel and hot electrons, is one way he’s passing his fire to the next generation.

The magic sub lights up the mind of everyone who sees her. She invites everyone to come on board and join the fight to heal the ocean.

Listen to her message. From climate disruption to plastic pollution to overfishing, the ocean is in peril. Take action. Go to tough places and do hard things. Find out who you really are.

The way ahead is not closed. Go there. Find out what needs doing. Do it. Your time, talent and tenacity are a gift come true. Be a leader. Carry the fire. You can change everything.


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