Fly Like a Cetacean

By Glen Martin|Tuesday, September 01, 1992
RELATED TAGS: GADGETS, OCEAN
Though the vineyards and Lucullan mansions of the Napa Valley are only a mile or two to the north, the ambience of the Napa Marina is decidedly middlebrow. The boats are mainly fishing or low-end recreational craft, not extravagant yachts. The slips and buildings, though well maintained, are modest. With their long hair and T-shirts, Thomas Doc Rowe and Dennis Dusty Kaiser blend in well here. In fact, the two self- described aging-hippie engineers, who normally work at Whiskytown Lake in Redding, some 150 miles to the north, look right in their element.

For a fact, they are in their chosen element: water. They’re standing knee-deep in the brackish, pea green effluvium of the marina, gazing disconsolately at the engine compartment of their Bionic Dolphin, also known as the VASH (for Variable Attitude Submersible Hydrofoil).

Damn, drawls Rowe. The seal between the engine plate and the transmission plate just isn’t holding. Nothing to do but take her back to the shop--we aren’t flying today.

Though the two men are palpably disappointed, they handle the setback with equanimity. They had hoped this would be the day that humankind realized the aqueous parallel to the Wright Brothers’ achievement: underwater flight. Unlike today’s unwieldy and painfully slow submersibles--deep-diving small submarines normally used for undersea research--the VASH is designed to mimic the speed and maneuverability of a real dolphin, diving and pirouetting underwater at speeds up to 30 knots (35 miles an hour). It’s a vision that has sustained the two men and their sometimes exasperated families through four years of design, construction, and hardscrabble fund-raising.

Forty miles south of the marina another aquatic flight project is unfolding in San Leandro, the home of the Deep Ocean Engineering company. While the VASH’s dolphin imitation will limit its diving to 200 feet, Deep Ocean’s submersible, called Deep Flight, will dive to 4,000 feet at 12 to 15 knots. The company was cofounded by Graham Hawkes, whose first sub, Deep Rover, plumbed the depths of Oregon’s Crater Lake in 1988 and 1989 (and was designed to be so easy to use, says Deep Ocean CEO Philip Ballou, that even a scientist could master it).

With Deep Flight you’ll be able to barrel-roll and swim with the great whales, says renowned marine scientist Sylvia Earle, Deep Ocean’s other cofounder and holder of the world’s record for untethered deep diving. With such maneuverability, the pilot will be able to interact with the marine environment, not just observe it; that will completely change our view of the deep ocean.

Civilian submersible technology is on the cusp of a breakthrough, one that will see the emphasis shift from horrendously expensive, slow- moving, ship-supported craft to mass-produced, speedy subs that fly. Deep Flight will quite literally fly, says Hawkes. With its wings and thrust, it acts just like an airplane, only in the medium of water instead of air.

Current deep-water submersibles rely on an old technology: ballast. Most contain a tank that is filled with water at the surface; the weight allows for descent. When the crew wants to come back up, the water is displaced by air from onboard compressed-air cylinders. The interlude from the top to the bottom in any abyssal dive is long. For example, on a recent seven-hour dive to 3,000 meters by the Japanese research sub Shinkai 6500, six hours were required for submersion and ascent, which left only one hour of bottom time. When combined with the puny viewing ports and the poky speeds of today’s submersibles--a few knots at best--the vessels make serious scientific research frustratingly laborious and slow.

That’s why the idea of flying subs with expansive viewing areas, speed, and ease of maneuverability is one that is ripe for development, though the research is still being conducted by small cells of true believers rather than large corporations intent on an attractive bottom line. Technically, flying submersibles could have been built years ago, Hawkes points out, but it just took this long for the breakthrough of imagination.

Both Deep Flight and the VASH are positively buoyant (that is, they are designed to float to the surface), and both resemble dolphins. The VASH tapers in back to a set of fins, with a second set of fins on each side. It’s about 12 feet long and just short of 3 feet wide at its broadest point. Deep Flight is a little bigger, about 15 feet by 8 feet, and its fins look more like the wings and tail of an airplane.

The subs differ more dramatically in their propulsion systems. The VASH, whose blue-collar designers hope it will become the Volkswagen of civilian submersibles, relies on a cannibalized outboard motor located inside its frame to generate power. On the surface, the outboard drives both the propeller and a turbine air compressor. Air is obtained through blowholes and pumped into a storage tank by a compressor. As the VASH submerges, the blowholes snap shut, the air needed by the engine is supplied by the stored air in the tank, and all the engine’s power is shifted to the propeller shaft. Rowe estimates the compressor will require just three to five seconds of surface time to fill the air tank, allowing for dives of up to 20 seconds, thus mimicking a dolphin’s leaps into and out of the water.

Fins on the side of the VASH work much like the airfoils on an airplane--the pilot determines the rate of descent and ascent by changing their angle of attack, or attitude. This part of the design was based on Rowe and Kaiser’s long history of ultralight aircraft design. Fins are like wings, so we just switched our thinking to a medium heavier than air, notes Kaiser.

The VASH’s interior resembles a cockpit; the pilot reclines in the crashproof Kevlar and fiberglass hull and controls fins, rudder, and throttles with a joystick and foot pedals. There’s no problem if we lose power, says Kaiser. Since we are positively buoyant, we just pop to the top. On the surface, the pilot looks out a windshield, much like that of a car. Below the surface, because the water and glass cause distortion due to diffraction, sight is obtained via a video camera; a screen rests between the pilot’s legs. The VASH has no instrumentation; as Kaiser points out, Orville and Wilbur Wright didn’t have any instrumentation in their first plane.

Deep Flight’s power plant is more upscale. It uses aluminum- oxygen batteries, which consist of racks of aluminum plates that are fused with a platinum catalyst. Salt water is the electrolyte. When the aluminum comes in contact with seawater, electricity is generated as electrolysis begins and the aluminum is slowly eaten away. The current is steady and the batteries are long-lived--electricity is generated as long as any of the aluminum remains, and the batteries are recharged simply by replacing the aluminum plates. Deep Flight also carries lead-acid batteries--the standard batteries in traditional submersibles. The system will allow Deep Flight to submerge for up to four hours.

The pilot lies flat on his stomach in a people pod, a heavy fiberglass tube fitted with a pressure-resistant acrylic dome. Fins, rudder, and throttles are controlled by hand. Flaps on the winglike fins control the degree of steepness of the dive. The sub carries the basic instrumentation of sonar, camera, and navigation equipment.

Deep Flight also uses its positive buoyancy as a safety feature. The people pod is secured by straps to the submersible’s frame, which houses all the propulsion and guidance systems. In case of a mishap, the pod can be jettisoned and recovered at the surface. Since the pods are maintained internally at one atmosphere, occupants won’t have to decompress as they surface.

While Deep Flight is an experimental vehicle (Hawkes compares it to the Bell X-1, the plane in which Chuck Yeager broke the sound barrier), it is still the prototypical means to a more grandiose end: Sylvia Earle hopes that future Deep Flight incarnations will allow scientists to track sperm whales as they dive for giant squid, the huge cephalopods that are known to haunt the deepest tracts of the ocean but which have never been seen alive. Ultimately Deep Ocean’s goal is to develop a more sophisticated generation of Deep Flight that would allow the routine exploration of any site on the ocean floor, including terminal depth, the deepest point of the planet’s oceans: at the bottom of the Mariana Trench, 38,520 feet below sea level.

The Mariana Trench has been visited only once before, in 1960, when Donald Walsh, now on Deep Ocean’s board of directors, and Swiss oceanographer Jacques Piccard descended in the bathyscaphe Trieste. The ascent back to the surface took three hours. When we go back, we wouldn’t want it to be a one-shot visit, says Earle. Our future submersibles would allow us to stay at terminal depth for sustained periods and be safe and comfortable while we’re there.

Eventually they hope to expand the size of the submersible’s frame to carry more pods and thus more people at one time. Earle also believes that once in mass production, each of the company’s relatively simple vessels would be very cheap when compared with today’s one-of-a- kind submersibles--they’ll cost a few million as opposed to a hundred million. Nor would they require expensive support ships. Since they’d be so light, they could be dropped from a helicopter or from any good-size ship without the special hydraulics, cranes, or berths on support ships that the current traditional submersibles need.

The whole goal is to make deep-ocean exploration something that isn’t out of the ordinary, but something that anyone can do, not just scientists, says Earle. If we’re going to understand and save the world’s oceans, we need that kind of public involvement.

And what’s the ultimate goal for the VASH’s crew? Rowe envisions the Bionic Dolphin joining up with a pod of its living counterparts: I think the only way to really learn about cetaceans is to become part of their society, and the VASH will let us do that. Adds Kaiser: I think it was Jacques Cousteau who said the dolphins will never respect us until we can do what they do. So we’ll just swim along with them.
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