Poised for the pit: The unique submersible is suspended from the mother ship before her descent into the deep.

‘It will take three years to build a rescue sub’

Hamish Harding’s 12-hour mission to the deepest part of the ocean, the Challenger Deep, broke world records – and two thrusters on his unique sub. Words: Mike Stones

Poised for the pit: The unique submersible is suspended from the mother ship before her descent into the deep.

‘It will take three years to build a rescue sub’

Hamish Harding’s 12-hour mission to the deepest part of the ocean, the Challenger Deep, broke world records – and two thrusters on his unique sub. Words: Mike Stones

WHEN HAMISH Harding began his record-breaking, near seven-mile dive into the world’s deepest ocean trench, he was comforted by the fact that, in the event of an emergency, his submersible carried four days’ supply of oxygen, food and water. Less comforting was the knowledge that the vessel is unique and it would take three years to build another capable of rescue.

At least he was not alone. Accompanying the chairman of Action Aviation on their 12-hour mission to the Challenger Deep – the lowest point on the planet’s surface – was Victor Vescovo, the submersible’s American captain, private equity investor, former naval officer, mountain climber and famed undersea explorer.

It was a deep dive that began with a business jet. “It was a classic example of how a business jet makes things possible,” Harding told Corporate Jet Investor. “In March 2021, due to the Covid lockdown, there were no flights from our home in Dubai to the island of Guam – the point of embarkation for the Mariana Trench that includes the Challenger Deep. Fortunately, we were able to use our Dassault Falcon 7X for the 11-hour direct flight, cruising between FL430 and FL450 [43,000 to 45,000 ft].”

A week later, Harding found himself bobbing in the waters of the western Pacific Ocean, aboard the purpose-built Triton submersible DSV Limiting Factor. The submersible had just launched from the expedition yacht DSSV Pressure Drop. (He is keen to explain the difference between a submersible and a submarine. “A submarine is capable of an autonomous voyage, whereas a submersible must be launched from a mother ship and re-embarked on the vessel after the dive”).

The submersible – the Triton 36000/2 – doesn’t so much resemble a submarine as a gigantic white suitcase with portholes and 10 fan-like thrusters (more about those later) mounted around the hull. Its modular appearance belies the high-tech wizardry jammed aboard the vessel – the world’s only full-ocean depth submersible. All external cables must contain high pressure oil to keep the electrical wires apart during the pressure experienced at extreme depth. Equipped with an array of sensors and controls, the vessel can monitor the full gradient of depth, temperature, salinity and other factors.

Cosy in the sub’s cockpit Hamish Harding (L) and Victor Vescovo pictured during the deep dive.

The mother ship DSSV Pressure Drop seen from from one of the vessel’s support inflatables.

It’s not unlike a business jet cockpit, according to Harding.

“The submersible’s pressure vessel is incredibly heavy because it has to be made of 90mm thick titanium to withstand the pressure. It’s a huge perfect sphere in the middle of the sub that keeps the two people safe. Inside, it’s no bigger than a small business jet cockpit – like a Citation CJ1.”

This confined space was home for Harding and Vescovo for their 12-hour dive. Denied the comfort of a lavatory during the mission, Harding reduced his intake of food and water. He had “precautions” in place but fortunately did not need to use them.

So, what motivated the dive? A combination of factors – beginning with a book: “Perhaps reading Jules Verne’s 20,000 Leagues Under the Sea as a boy planted the idea of a dive to the deepest part of the ocean,” recalls Harding. “But I never thought it would be possible.”

“It’s much quicker to communicate between the Moon and Earth.”

Then, there was the opportunity to break more world records. Harding has developed a taste for busting records, following his 2019 One More Orbit flight, which smashed the pole-to pole-world circumnavigation speed record in a Gulfstream G650ER. Two more entries in the Guinness Book of World Records are likely to bear Harding’s name alongside Vescovo. Though yet to be confirmed, the records will be for longest time spent at full ocean depth – 4.3 hours breaking the previous record by 90 minutes – and the longest traverse at full ocean depth – 2.86 miles (4.6 km) horizontally across the trench floor.

There was a third reason – motivated by the desire to monitor that scourge of 21st century living – plastics. Every year, 8m metric tons of plastics enter world’s oceans to swell the tide of an estimated 150m metric tons that circulate our marine environments, according to the non-profit environmental advocacy group Ocean Conservancy. Harding wanted to discover if any plastic could be found in the deep ocean.

So, as Harding squeezed into the tiny cockpit of DSV Limiting Factor, with his captain Vescovo, was he worried about the calculated risk he was taking in making this, the deepest of all, ocean dives? “No. I have this problem with not getting as concerned as I probably should,” he says. “One probably shouldn’t overvalue one’s life too much.”

Also, he was too occupied to focus on what might go wrong. Harding and Vescovo shared the duties aboard their tiny vessel. Navigating the submersible, monitoring its vital systems, communicating with the surface and taking photographs and videos left little time for worry. While the sub is packed with 21st century technology, its speed of communication at depth is strictly of the 1980’s era. “It’s much quicker to communicate between the Moon and Earth – 1.5 seconds each way – than to send or receive a message at the bottom of Challenger Deep – 7 seconds,” says Harding.

But there must have been concerning moments? Harding pauses for a moment to remember. “During the traverse at full ocean depth, we climbed an unmapped undersea mountain the size of Table Mountain in Cape Town. We came into contact with the mountain a couple of times.” He pauses again to rephrase: “Well, let’s just say we gently nudged it.” One of the “nudges” was sufficient to disable one of 10 thrusters responsible for the propulsion and steering of the sub. Another had been disabled before the launch but, rather than miss their dive slot, the team decided to press on with nine.

One of the two autonomous landers that aided navigation.

Worm’s eye view: Shrimp-like creatures feast on a bait fish.

“Relying on eight thrusters out of 10, was OK in the end. We were crabbing across the ocean floor sideways. The only problem was we couldn’t fully see where we were going,” says Harding. “Due to the position of the portholes, when climbing the mountain, we had to look down and anticipate how it was rising. But if you reach a sheer vertical wall, it’s very hard to predict that – it’s difficult to climb fast enough to avoid a vertical wall.”

My son Giles was rather hoping we would see a megalodon. Sadly, none were visible.”

Visual navigation was supplemented by sonar guidance from two landers dropped before the dive. The autonomous devices, which bob to the surface after the mission, are placed in known locations to enable the team to triangulate the sub’s position.

Fortunately, the voyage was not disrupted by the creatures that starred in Jules Verne’s classic novel – the giant squid or any other deep-sea denizens. This was a disappointment for at least one person. “My son Giles, who joined the expedition on the mother ship to co-ordinate social media coverage, was rather hoping we would see a megalodon. Sadly, none were visible – I suspect they are creatures confined mainly to Hollywood.”

But the deep ocean floor was not entirely devoid of life. “We managed to bring back some genuine Challenger Deep shrimp-like creatures, called hadal amphipods,” explains Harding. “It’s incredible to think that they have survived as a species for millions of years at a pressure of 1,200 atmospheres.”

What lies beneath: A circular view of the deepest point on planet Earth.

Deep view: The mission’s Triton submersible.

While they found no plastic bags or pack rings floating in the darkness, Harding believes there may be contamination with microplastics. Water samples collected from the Challenger Deep are being tested for the presence of plastics at Aberdeen University in Scotland.

Although only two men were aboard the sub, they were supported on the surface by a crew of about 30. “Without them, and the marvellous technology of the sub, Victor and I would soon have been dead.”

Speaking on behalf of the submersible’s manufacturer, Triton co-founder and president Patrick Lahey told Corporate Jet Investor that Harding’s dive was further proof of the company’s own successful mission. In building the Triton 36000/2 or Limiting Factor (LF), the manufacturer aimed to create a revolutionary new submersible design, which provided safe and reliable daily access to the deepest and most remote parts of the ocean for the first time in history.

“The significance of the dive with Hamish Harding and the other people who have now had the privilege of seeing the Challenger Deep with their own eyes from inside the LF, is it proves Triton was successful in opening a doorway to the most enigmatic and least understood area of our world,” said Lahey. “The LF has fundamentally changed our relationship with the deep ocean and all of us at Triton Submarines are immensely proud of this achievement.”

As the sub rose close to the surface and the crew began to buckle up for the “rodeo-like conditions” in the choppy ocean swell, it was to the technology that Harding’s thoughts returned once more. “To create something that can travel 4.6 kilometres horizontally using electrically powered thrusters outside the pressure vessel and can manoeuvre like a helicopter in the deepest part of the ocean is amazing. The deep ocean is truly one of the last few unexplored frontiers – without going further into space. More men [24] have travelled to the moon than have visited the bottom of the Mariana Trench [Harding was the 19th in history].” And, he was relieved their craft performed flawlessly – without the need to wait three years for the construction of a rescue sub.

Thumbs up before going down: Hamish Harding bids farewell before the deepest dive on the planet.

The deep dive – in numbers:

1 – Submersibles capable of making the dive

2 – People to have traversed the Challenger Deep furthest

2.86 – Miles (4.6 km) the length of the record deep-sea traverse

8 – Tonnes per square inch they experienced at the bottom of the Challenger Deep

10 – Thrusters on the submersible (two of which were not functioning by the end)

12 – Hours of the mission. Includes four hours each of descent, traverse and ascent

19 – Hamish Harding’s ranking in the total number of people who have reached the bottom of the Challenger Deep

12,000 – Atmospheres of pressure on the deep ocean floor

35,856 – Depth in ft (10,929 m) of the Challenger Deep.

Action Aviation – at a glance:

Action Aviation, established in 2004, is an international business jet brokerage company offering a range of services in the business aviation industry, including aircraft financing, getting aircraft operational for clients and aircraft wet and dry leases. The firm provides aircraft brokerage and advisory services to owners who wish to sell, as well as buyers in the market for the first time or those who want to replace/upgrade their existing aircraft.

CJI Connect

Hamish Harding Chairman, Action Aviation [email protected] +971 50 251 8958

Patrick Lahey Co-founder and president, Triton [email protected] +1 772 770-1995

Mike Stones, Group editor, Corporate Jet Investor

Mike Stones, Group editor, Corporate Jet Investor