Unless you're a submarine pilot, it isn't every day you get to pilot a submarine, and so I'm in Malta to test drive U-Boat Worx' C-Explorer 2. The 2 isn't a version number, but denotes that this is a two-seater submarine. Coincidentally, it also denotes roughly the number of millions of euros you'd need to buy one. It's a millionaires' plaything designed for exploring under the sea to depths between 100 m (328 ft) and 1,000 m (3,280 ft), depending on the spec. My mission: to explore a wreck at the bottom of the Mediterranean Sea. Equipped with U-Boat Worx' GoPro video cameras in and outside the sub, my trusty point and shoot camera and a dictaphone smartphone app, I'm as ready as I'll ever be for my appointment at the seabed.

Mike usually handles these sorts of assignments for Gizmag. Back in April he tested the Seabreacher X, a shark-shaped marine recreational vehicle with the power to weight ratio of a Bugatti Veyron. And though the C-Explorer 2 is designed for more sedate speeds, it boasts some serious specs of its own to operate at depth. However, I'm nearest to Malta and so the job of trying out the C-Explorer 2 falls to me. I mention this because of one crucial difference between Mike and me: he isn't a coward. This will become relevant. (And while I'm inappropriately shoe-horning footnotes into the introduction of the article, I should mention that this all took place last Tuesday. I'm writing in the present tense because I'm told it heightens the drama. Brace yourself.)

My first glimpse of the C-Explorer 2 is from the small tender taking me to the Alk, a former German research yacht acquired by U-Boat Worx for transporting its submarines to choice dive sites around Europe. Utilitarian as yachts go, the Alk is still an impressive vessel, made more so by U-Boat Worx' addition of a mighty yellow hoist for lowering and lifting its subs into and out of the water. The C-Explorer 2 is already at sea, a good 50 m from the Alk.

Aboard the yacht I'm asked to sign a document saying something along the lines that U-Boat Worx is in no way responsible should I swallow 20 gallons of seawater and fail to make it back alive (it's possible the actual clauses in the document were less specific). Before I'm allowed anywhere near the sub I must receive a safety briefing from Erik Hasselman, officially the company's Sales and Marketing Manager but also its foremost sub pilot (where better to sell one than than at the bottom of the sea?). I am also asked to divulge my weight and divest my shoes. Slowly I'm becoming less apprehensive. It's clear that U-Boat Worx takes safety deathly seriously.

Approaching the sub (Photo: James Holloway/Gizmag)

Soon after, we're back in the tender for the hop to the sub itself, which is undergoing final preparations by another member of the team. Here it becomes obvious why they want to know my weight. The sub is loaded with additional ballast so that, once the ballast tanks are flooded, the sub reaches neutral buoyancy below but near to the surface. If the pilot lets go of the controls at depth, the sub should rise slowly of its own accord. I suspect that they add less ballast than is usual.

After passing across my various gadgets, I'm helped aboard the sub (which, irrationally, is perhaps the most hair-raising moment of the whole experience), and directed to stand on the black grippy surfaces rather than the yellow hull, an error that would lead to an almost certain dunk. I follow Erik into the cockpit, lowering myself into the passenger seat through the top hatch above. Initially Erik takes the controls, and with good reason. There are numerous checks and readings to carry out, which Erik relays via radio to the rest of the team. Though entering and exiting the hatch isn't difficult for a relatively fit, able-bodied person (or even myself), the company can make clamshell variants of its subs in which the entire top half of the sphere opens up for easier access.

At the surface we travel to a buoy marking the location of our wreck: the Imperial Eagle, some 42 m (140 ft) down. This is when the C-Explorer 2 expends the most energy, battling against the surface tension of the water. Its natural habitat is beneath the surface. Later, Erik will tell me about its more popular C-Quester range of subs which, thanks to its boat-like hull performs better at the surface. Its undoubtedly more of a looker, but the hull compromises both performance and visibility under the surface which, in a submarine, one would think would be where you want it. Both subs sport a spherical acrylic cockpit, but in the Explorer your visibility is impeded only by the essential components. Give me a C-Explorer 2 any day. No really. Do.

Beginning the dive: an odd sensation (Photo: James Holloway/Gizmag)

With the hatch closed, the cabin pressurized to 1 atmosphere and the final checks made we're ready to dive. Erik floods the tanks and we begin to sink. It's okay, we're supposed to sink, I remind myself. Before long, the entirety of the C-Explorer 2's spherical hull is beneath the surface. It's a peculiar sensation, but not, in the end, an alarming one. It's reassuring that U-Boat Worx is a serious outfit, and the C-Explorer 2 a serious piece of equipment, and yet there's undoubtedly some human psychological quirk in play, the feeling of being safely cocooned within an impermeable bubble. Motorists will know the feeling. But U-Boat Worx won't sell you a sub unless you complete its training program, which means completing 20 accompanied dives.

Erik tilts the sub first forward than back pushing then pulling the vertical throttles in opposite directions to ensure the tanks are fully flooded. Once below the surface, the sub is propelled forwards and backwards by two 2-kW propellers. Two more control sideways motion. Each propeller is controlled from a bank of four throttle levers in the pilot's control deck. A joystick could be used, Erik explains, but throttle levers are more immediate, and surprisingly easy to master. Children take to them faster than anyone, apparently.

As we descend we follow a shot line suspended on a buoy marking the location of the Imperial Eagle, not far from Malta's Qawra Point. Originally named New Royal Lady, the boat entered service in 1935, entertaining passengers with pleasure cruises setting out from Scarborough, England. It was requisitioned by the Royal Navy in 1940, and after the war returned to civilian duties on the Firth of Forth and then the Thames as the Crested Eagle. In 1957 she was sold to E. Zammit & Co. and renamed the Imperial Eagle to ferry passengers between Malta and Gozo. She was scuttled in 1999 to create an artificial reef as an attraction for divers.

Being able to see out of the bottom of the C-Explorer 2 is fantastic (Photo: James Holloway/Gizmag)

But before we visit the wreck we first follow a short crevasse to Kristu l-Bahhar, a 13-ton statue of Jesus, blessed by Pope John Paul II during a visit to Malta in 1990, and lowered to the bottom of the sea as a lucky charm for Maltese fishers. It takes us about four minutes to get there from the surface, and though in our safety bubble it doesn't feel all that deep, we are already at the recommended limit for recreational scuba divers. Erik turns on a light which boosts visibility, if only at limited range.

After circling the statue it takes only a few minutes to find the Eagle. As it emerges from the blue, 10 minutes into the dive, an alarm sounds. Fortunately Erik told me this would happen. It's a dead man's alarm which sounds every 10 minutes, and which must be actively disabled by the pilot to continue the dive. If not, compressed air will fill the ballast tanks, expunging the water, causing the sub to rise to the surface. In the event that system fails, the sub can sustain life for 96 hours, a deployable buoy marking the sub's position.

Every 15 minutes, Erik performs another system check, checking the battery status readings on one of two main displays (the other shows our "altitude" above the seabed). A control panel with numerous dials and switches is located behind us. It's not all high-tech. Erik describes an ordinary stop watch as the cheapest part of the sub, and a compass is stuck to the battery display screen.

The Imperial Eagle comes into view (Photo: James Holloway/Gizmag)

As we circle the wreck, turning occasionally to face the fish seeking refuge within, I'm struck by how serene and beautiful it is. It's a credit to U-Boat Worx that the C-Explorer 2 feels completely safe, so one is free to set about the serious business of fish-spotting, studying the detail of the wreck and soaking in the azure (though strictly in the figurative sense). Visibility is somewhat reduced by a patchy sheet of cloud, but I feel that I can see some distance.

Twenty-five minutes into the dive and facing the wreck, I switch seats with Erik and take the controls. It turns out I'm a cautious submarine pilot, partly because the curvature of the acrylic hull has a foreshortening effect on distance, and partly because I'm acutely aware that I'm in control of a €1.4 million (US$1.8 million) piece of machinery – the barebones, shallow-diving version of the C-Explorer 2. The average price, with a few extras thrown in, is about €1.8 million to €2 million. Later, back aboard the Alk, I'll have a chance to speak with U-Boat Worx owner Bert Houtman, who'll tell me the aim is to increase sales from the current level (a handful of each model per year by the sounds) and reduce the price, making the submarines more viable for research purposes. Gizmag originally reported that the C-Explorer 2 would cost six figures rather than seven, which doubtless remains the company's aspiration.

At one point Erik assures me I'm still a few meters from the wreck even though it appears to be only 18 inches away. Our model can dive to depths of 100 m thanks to its 2-inch thick acrylic cockpit. In the 1,000 m version this would be 7 inches thick. In any case the acrylic shell is one of the most specialized parts of the sub, made by UK specialists. U-Boat Worx keeps a few in reserve due to the long lead time. In the latest versions being made, the band of aluminum joining the two acrylic hemispheres is done away with. Instead, the two halves are glued, increasing the field of view even further.

Turns out I'm a cautious submarine pilot (Photo: James Holloway/Gizmag)

Because I have a tendency to let the sub rise, we tend to hit the current flowing over the wreck, slowly carrying us away (Erik tells me this is not a good thing). Even so, piloting a submarine with such a large field of vision is incredibly good fun and surprisingly easy. The controls are more responsive than you'd think.

After an hour's diving we agree to head back to the surface. Back in control, Erik takes us steadily back up the shot line. At 10 m from the surface, he requests permission to blow the diving tanks, and with a howling rush of decompressing air, white light washes away the blue and we return to the realm of air-breathing creatures.

Back aboard the Alk I observe the involved process of hoisting the sub onto the deck. It's a five-person job in which two people are employed to lean on the C-Explorer to stop it swinging into the stern. It's not something you'd want to try on rougher seas. Safely on deck, there are more checks to carry out, and the whole sub has to be washed down with freshwater – otherwise it will be gone inside of a year thanks to the corrosive power of seawater. It becomes clear that the cost of acquiring the sub is only the beginning: you also need a yacht and a crew. I give up on negotiating a discount.

At times it's a five-person job to get the sub aboard the yacht (Photo: James Holloway/Gizmag)

Though the main market for these subs is private users, there is interest from academia, and particularly marine archaeologists and biologists who could potentially capitalize on the extended dive times (up to 8 hours in the case of this C-Explorer 2), not to mention comfort, such vehicles afford. There are also five-seat versions with business could use to charter. In these the pilot sits at the back of the cockpit, and requires video display screens to aid visibility. In the five-seater variants, passengers are given viewing priority. It was a five-seat C-Explorer 5 that Vladimir Putin was recently photographed taking a dip in.

Despite the shot in the arm James Cameron has given the profile of small submersibles, there are relatively few players in the field. But the market is growing, and U-Boat Worx hopes that more than half of small civilian subs sold will be of its design. Even if the cost does come down as is hoped, it will remain out of reach of us ordinary folk, but it may be that charter subs begin to appear at the world's most interesting dive spots. I hope that happens. Diving in a mainly-transparent submarine is an unforgettable experience (behind the controls or no). Just make sure you ask to see the pilot's license.

We'll upload a highlights video from the dive next week, but for now you can see more images from the dive in our image gallery.

Further info: U-Boat Worx

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