America's Top Designer of Hydroplanes Tells
What Puts the Speed in a Champion Speedboat
By Elliot Marple
What makes a champion hydroplane?" I asked Ted Jones, greatest designer of speedboats in America. "Obviously it's not just design or power."
"You might say," Jones answered, "that it's all the little things your competitor overlooked." Turning away from his newest hydro, Miss Bardahl, which he was readying for the 1958 racing season for unlimited hydroplanes, he explained:
"Design counts, and power, and they've got to be in the right combination. But little things can be vital, too --the shape, size and location of the rudder; the size of the propeller with respect to gear ratio; the location of the prop; the size and shape of that tiny skid fin; the construction of fuel tanks, and even the driver's seat."
Jones pointed to the narrow-backed padded seat in Miss Bardahl. Norm Evans, the driver, is an ex-welterweight boxer. His hips are slim, and the seat was tailored to his fit. Padded armrests are built in close to the body, then undercut to leave room for his thighs. "If the pilot is held snugly he can do better than if he's tossing around," Jones explained.
"Individually," he went on, "details don't amount to much, but collectively they can lose you a race. Take the fuel tanks, for instance."
Tanks are welded aluminum wrapped with reinforced fiber-glass in Jones' boats. If a crack appears, a little resin and glass cloth will permit repairs between heats.
"When you go into a turn at 140 m.p.h., fuel is thrown high up against one wall in the tank," Jones said. "That leaves a void and the fuel line draws air. As a result you backfire and slow down, or even blow part of the engine off. To prevent this, we have a partition that traps some gas over the fuel opening."
The water pickup, too, must be just right to ensure proper engine cooling, whatever the speed of the boat. Miss Bardahl's cooling system is designed for a constant water pressure of 25 p.s.i. At higher speeds, when the pickup pressure is much greater, a spring-loaded relief valve opens, keeping pressure constant.
Because he has come so far in hydroplane design in the last dozen years, Jones can afford to concentrate ' on the little things. His first unlimited, Slo-Mo-Shun IV, went into racing in 1950 and revolutionized hydroplane design.
In the years just before Slo-Mo, the best heats in Gold Cup races generally ranged between 52 and 70 m.p.h. Last year's Gold Cup saw speeds almost twice as great. And every boat in it was either a Jones design or an obvious copy.
The new Miss Bardahl, the second unlimited that Jones has designed and built, has a number of innovations meant to eliminate faults in earlier racing craft.
An example is the air spoilers, which Jones introduced in the original Slo-Mo. A hydroplane travels as fast as the far heavier DC-3 airplane; the DC-3 takes off, the hydroplane must not. The hydro rides on a wedge of air that flows between the water and the hull and is trapped on the sides by the vertical edges of the sponsons. But the lift from this wedge of air must be no greater than hull weight.
Jones borrowed from the aircraft industry the idea of a spoiler that would break the flow of air under the hull and reduce lift as the bow rose. The spoiler also prevents "nosing in" in rough water.
In Miss Bardahl, Jones has made a strategic shift in the location of the spoiler. In place of a single central spoiler he attached two smaller ones right to the sponsons. Why?
High-speed crackup last year at Madison, Ind., ripped hull off Miss Thriftway. Nose dive after hitting a swell at 165 mph did it. Driver, Bill Muncey, thrown clear of wreckage, survived.
"Last year, racing at Madison, Ind., Miss Thriftway hit a swell from a cruiser, went up in the air, and came down at an angle on her nose. The force of water caught the dihedral of one sponson and tore the boat apart diagonally. Now we've built the spoiler into each sponson, giving the sponson a V bottom, so when she hits a turn at excessive speed the water won't catch and rip it off."
On Miss Bardahl, Jones also tapered the forward deck to a thin edge where it joins the hull at the very bow of the boat. Three layers of fiber-glass cloth have been laminated around the edge for greater strength with very little increase in weight. Why was it added? Again Jones points to a failure in an earlier racer:
"In the 1956 Gold Cup race at Detroit, Bill Muncey, driving Miss Thriftway, struck a vertical wall of water near the Belle Isle Bridge. The water got in between deck and hull and instantly lifted off 12 feet of the deck."
The forces involved when a hydroplane tears over the water at 150 to 180 m.p.h. are tremendous. At that speed, "the force of a sheet of water is like a giant knife," says Jones. "It rips, tears, and cuts. The faster you go, the sharper the knife. When Miss Thriftway had her accident, the water tore 3/16-inch duralumin like tissue paper--metal so strong that we couldn't straighten it out with a hammer. This edging keeps the water out."
Another innovation in Miss Bardahl is the plastic fin or tail of molded fiber-glass and polyester resin. The tail was introduced to hydroplane racing in Slo-Mo IV to help the driver hold his course at high speeds and offset the side thrust of the prop. But until this year's Miss Bardahl, the fin required outside struts for its support, a constant hazard to the driver. If he is thrown out and strikes a strut, he might be cut in two. The plastic fin, with internal supports, eliminates that hazard and gives the boat cleaner lines.
For better control on the turns, Miss Bardahl has a larger, longer non-tripping chine. This is the 45-degree angle along the side of the hull, starting narrow just aft of a sponson and widening as it extends to the stern. The non-tripping chine-called the "non-trip"-comes into play mainly in rough water. When a hydro takes a fast turn, it rides the chine.
Up to now a driver starting a turn at 120 m.p.h. would come out doing 80 m.p.h. But better lateral support from the larger chine should enable him to start at as much as 155 and come out at 110.
Extra strength has been built into Miss Bardahl in many places, frequently with a saving in weight through use of duralumin. In a number of places dural is bonded to plywood. The sponsons and non-trip chines, formerly planked with plywood, now have 1/8-inch dural.
Use of aluminum-plywood laminate cuts about 500 pounds from the weight of the boat, holding its total weight without engines close to 3,000 pounds and making for faster acceleration.
The construction of Miss Bardahl borrows more from the aircraft industry than from marine design. "There is not one piece of marine equipment in the boat," Jones observes. Aircraft bolts are used more and more in place of screws. The propeller is not bronze, but a heat-treated steel forging 25 times as strong as the prop of a pleasure cruiser.
The special props cost $625 each, and an unlimited hydro should have six as a minimum-two sets of three different pitches. The prop used will vary with the condition of the water and altitude. (High altitude calls for less prop pitch.)
Unlimiteds don't come cheap. The initial cost is approximately $30,000, and that's just a starter. If Miss Bardahl blows four or five engines and a couple of gearboxes, the preseason ante goes up fast. The sponsor, Bardahl Manufacturing Corp., Seattle, also carries on its year-round payroll Norman Evans, driver; Del Gould, crew chief; and Rudie Boppel, lead engine man.
For Ted Jones this is a year when, more than ever, he appears to be racing against himself in the Gold Cup. The new Miss Thriftway, slightly larger and heavier than Miss Bardahl, is another hydroplane off the Jones drafting board, and Jones is manager of two Thriftway boats in the 1958 racing circuit. Other, older boats of Jones' design are out competing for honors, too.
Tall, high-strung, and with a trace of gray showing in his black hair, Jones has lived and breathed boat racing for most of his 48 years. As a hobby, he started to design and race limited hydroplanes in 1927. Working at Boeing Airplane, he saw what lessons aerodynamics had to teach in speedboat design.
He struck up an acquaintance with the late Stan Sayres and in 1942 offered to design an unlimited hydro for Sayres without charge, in return for the privilege of driving it through the mile, the Gold Cup, and the Harmsworth trophy race. That first boat was Slo-Mo IV.
In 1951 Jones set up his own shop in Seattle to make Slo-Mo V. Today his business is designing and building fast boats. Later this year, as a by-product of the design of unlimiteds, he will start production of a three-point outboard. This little outboard, carrying three men in choppy water, turned up 78 m.p.h. in an early spin in Florida.
Three-point racers ride on air, which has far less friction than water. They touch water at only three points: the after ends of the two sponsons and one blade of the prop. At 165 m.p.h. the prop lifts about 750 pounds, but the sponsons carry no weight; they provide only balancing while the boat rides along on air.
As an illustration of the saving in power with a three-pointer: The fastest Gar Wood hit in the days before Slo-Mo IV was 124 m.p.h., and that with four supercharged engines turning up 7,600 hp.-the power of a B-29 bomber. But three-pointer hydroplanes hit far greater speeds with only 2,000 hp and at 124 m.p.h. use only 700 to 800 hp.
Beyond this year? Jones looks to much faster speeds in racing and with a completely different source of power-the jet engine such as is used to drive the Boeing B-47 bomber.
Miss Bardahl's present engine turns up 4,200 r.p.m. The gearbox steps this up to the astonishing prop speed of 11,550 r.p.m. I remarked that it was too bad the driver could not shift gears. Jones grinned. "Right. Two speeds in the gearbox, one for the turns and another for the straightaway, would be a driver's dream."
A hydraulic mechanism might do the job, but the cost would be prohibitive and the box would weigh too much to be practical in racing, Jones believes. "The prop and the gearbox are the limiting features in today's big hydroplanes," he says. "The hull itself is good for at least 235 m.p.h., but we can't get a prop that will stay together at those speeds. That's why the jet engine looks so good."
(Reprinted from Popular Science, August 1958, pp.103-6, 200)
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