"A lot of engineering went into this boat," says Wynne, who designed the first successful turbine-powered ocean racer. "You don't just put a thing like that in there." The water-jet pump alone took Pratt & Whitney engineers three years to sort out, and when they mounted the first one in Formula 322 they weren't at all sure their tests in the lab at West Palm Beach had given them all the answers.
Says Project Engineer Carl Comolli, "We were afraid at the time we installed it in the boat that when the driver socked full power to it, the pump might cavitate [i.e., just open up a big air bubble] and not give thrust right away." It was also feared that the pump would stall or become powerless in high-speed turns. Worse, with the boat running in reverse, engineers were afraid the jet squirting back under the boat would cause turbulence in the water intake, starve the pump of water and thereby rob the boat of power.
Happily, however, all these fears were unrealized, and almost from the beginning pump and turbine ran smoothly, potently and with few hitches.
But the designers still worried that garbage, driftwood and other water-borne debris might be sucked into the pump to gum up the works. To find out they deliberately fed the pump a diet of hardwood plugs. It quickly swallowed the mess, apparently with considerable relish. Again, to satisfy the engineers that the pump wouldn't fly apart should the boat run aground, another experiment was performed in the lab. "We put tons of sand in it to see what would happen," cheerfully explains Dr. R. A. Schmidtke, P. & W.'s chief of research. "But instead of ruining the pump, the sand simply polished up its stainless-steel rotor."
Later, on the water, the pump sucked up a length of nylon rope. On a propeller-driven boat such an accident would have meant sending a diver overboard to cut it free. But not on Formula 322. Within the safe, dry confines of her spacious cockpit a crewman merely opened up an inspection plate, reached inside the pump and unwound the tightly turned coils of nylon.
So why don't all boatmen promptly scrap their diesels and their stern drives and buy a turbine-powered water jet? Well, for one thing, it will cost them around $40,000 for the turbine alone—a sizable price even for a wealthy yachtsman. "To the man who can afford the initial price and who can prorate the cost of a turbine over several years," says one Pratt & Whitney technician, "a turbine makes sense. But anyone who thinks they're just around the corner for the average boat owner is fooling himself."
Jim Wynne and Thunderbird President Dick Genth do not agree with this pessimistic appraisal. Says Genth, "Wait until they get this Vietnam thing straightened out and military contracts begin shrinking; then turbine builders will have to start thinking about the civilian market. Also, there'll be surplus helicopter and airplane turbines around. Besides, you've got to remember this engine's not that expensive. In ocean racing after nearly every race you've got to pull piston engines. You're talking about eight to 10 engines a season, and at $4,000 to $5,000 each, that adds up. For all intents and purposes, the cost of turbines is the same." Indeed, Wynne believes turbines will one day sell for less than diesels. Other Thunderbird engineers are even more optimistic, guessing they'll go for little more than gasoline engines.
The price still makes the turbine-powered runabout the boat of the future rather than the present, but Wynne believes that turbines now make possible—for those who can afford them—big yet extremely fast power yachts. "We simply couldn't do this with any other kind of engine because they'd fill up the boat, leaving no room for cabins, galley or any comfort," he says. "Fifty-footers used to do 20 knots in a pinch. With turbines we can move up the ladder to 35 or 40, yet not give up anything in the way of accommodations."