A new type of submersible craft based on the principles of flight may soon help to reveal the secrets of the oceans. John May reports
Deep Flight, a revolutionary submersible based on principles never employed before in undersea craft, may make it possible to explore a huge area of the planet largely inaccessible to us - the deep ocean. Deep Flight's inventor, Graham Hawkes, points out that about half a dozen ageing submersible craft can carry people little more than halfway to the deepest part of the oceans. His craft may be the key to uncovering the secrets of this last planetary frontier.
Hawkes is a mechanical engineer who began work designing submarine torpedoes for Plessey in Ilford. He left to set up a company called Osel in Great Yarmouth, developing offshore submersibles and atmospheric diving suits "in the Wild West days of the North Sea oil industry". He then went to California, believing the investment climate there was better for the more advanced technologies he wished to develop, and established Deep Ocean Engineering, which builds robotic systems for subsea use.
Despite the company's success, it did not satisfy Hawkes. "I have a strong interest in manned systems because they are articulate, capable and intelligent," he says. "Robotic systems are limited by the fact that they are linked to cables. Manned systems may be out of favour at present but, as we go deeper, the rationale becomes stronger."
So, with his wife, Karen, he established Hawkes Ocean Technologies (HOT) to turn his dreams into reality.
Hawkes has built 65 craft and has always done all his own test diving. He also holds the world record for the deepest solo dive in a submersible - 945m (3,100ft). He is thus familiar with the ocean world and this experience, combined with his impressive engineering and construction record, makes his vision for the new craft both credible and exciting.
Deep Flight is a new class of submersible, fundamentally different from all previous underwater craft. Because humans are subject to gravity, they have an instinctively rigid concept of up and down. Consequently, previous submarines and submersibles were designed with inherent stability so that they would remain horizontal underwater. They also use a combination of ballast, buoyancy tanks and weights to change their apparent weight in the water, causing them to sink or rise.
By contrast, Deep Flight is shaped, styled and streamlined, like an aircraft or a dolphin, to move in any direction through the water. Powered by thrusters, it uses the control surfaces on its short, fixed wings (configured the opposite way to an aircraft) to climb and dive at will. Moveable aft wings provide control.
The pilot lies prone, and views the ocean through the craft's acrylic nose, inside what HOT calls its Bio Shell: its goal is to place and hold the pilot in the position naturally chosen by humans experiencing artificial weightlessness underwater - head first, face down and body aligned in the direction of swimming (in this case, along the axis of the craft). The pilot "flies" the craft using joysticks that operate a fly-by-wire system.
Hawkes's aim with the Deep Flight programme is to develop a generation of lightweight manned submersibles that can operate economically, and independently of research ships and commercial fleets. To achieve that, he has had to shrink the bulk of a submersible down to the size of a microsub. Deep Flight is, in fact, more like a deep-diving suit than a small submarine.
Deep Flight 1, the proof-of-concept vehicle, did its trials off the Californian and Mexican coasts earlier this year. Built at the cost of $1 million (about £625,000) and made of glass-epoxy composites, this one-person experimental vehicle - 4.6m (15ft) in length - uses battery-powered thrusters to travel in any direction at speeds up to 12 knots and is capable of reaching depths of 1,006m (3,300ft).
Having proved the principles of the craft, HOT has now completed the engineering and design work on Deep Flight 2. This one's shell will be made of advanced ceramic materials, developed by the US Navy's San Diego Labs and to withstand the pressures at great depths.
Hawkes aims to "fly" the craft to the bottom of the Marianas Trench. Located near the island of Guam in the Pacific, it is the deepest point in the world ocean - around 11,000m (36,090ft). At that sort of depth, the pressure is more than 18,000lb per square inch. Hawkes and Deep Flight's chief scientist, Dr Sylvia Earle, call this project Ocean Everest; if Everest were placed in the Marianas Trench, it would still be covered by 2km (1.25 miles) of water. The price tag for the craft and the journey is $7 million.
Only two craft have ever plumbed the Trench: the bathyscape Trieste, on January 23, 1960, with a crew of two; and Kaiko, an unmanned Japanese probe, which landed on the ocean bed and recorded a depth of 10,911m (35,797ft) on March 24, 1995. The greatest depth attained by a manned submersible currently in service was 6,527m (21,414ft), achieved by the Shinkai 6500 in the Japan Trench, on August 11, 1989.
"We want to go to the Trench because people are still terribly preoccupied with depth," says Hawkes. "It's like flight before the sound barrier was broken - it was a psychological barrier. We want to show how shockingly easy it is. In the history of flight, the first question was: can you fly? Then it was: how far? Now it's simply: how long is it going to take? In Deep Flight, it will be a 30-minute flydown to the mid-ocean ridge and 60 minutes to the bottom."
Deep Flight 2 is, however, primarily designed with more workaday tasks in mind. Constructed on a modular basis, it can be easily reconfigured on a ship's deck to become a single-person craft for surveys and exploration; a two-person craft, to carry an observer; or a twin-pilot craft with a container for tools and samples, enabling it to be used as a heavy-duty work vehicle.
But is there a demand for such craft? "Commercial reasons for access to the deep ocean is a lot of time out in the future," admits Hawkes. "Only Japan has a longer view of the technology. An alliance of government and heavy-engineering companies has invested $0.5 billion in the Japanese Marine Science and Technology Centre for deep-ocean research." Founded in 1971, the centre developed both the Shinkai craft and the Kaiko probe.
"Think of the seabed as part of the planet's surface, and just as rich in geological features," says Hawkes. "The funding for exploring it is much more difficult than the engineering. These winged submersibles have gone off the end of the chart where normal sources of funding apply. Probably the most practical sources of funding will be the media." (Backers so far have included National Geographic and TV New Zealand.)
Hawkes reckons he can have two of his new craft completed within 18 months of receiving $4.5 million. "This is a quarter of the cost of competing in an America's Cup campaign," he says. "One of the hallmarks of Deep Flight is that we have never gone out for government money, or competed for the scarce money for scientific research in the ocean. We have designed it to make it look the part, as if it belongs to the future. We are tweaking people's imaginations."
Now Hawkes is also hoping to form the Society for Earth Access (SEA), the world's first underwater aviation school. He believes that, with these new craft, he has created the possibility for a new area of sport: underwater aviation or hydro-acrobatics. Deep Flight craft can barrel-roll, dive-bomb, breach and carry out other manoeuvres at depths ranging from 15m (50ft) to 1,006m (3,300 ft) underwater.
However, the bottom line for Hawkes is that a huge area of the planet, "has never been seen by human eyes. It is a huge 3D space populated by really interesting lifeforms. The seabed is like the surface of an alien planet. We have to get out of our straitjacket of thinking and realise we are living on an ocean planet."
