Schock 40

An updated version of the Twin Foil System is now available in this 40-foot sportboat by W.D. Shock Corp.

One of the best things about reviewing new boats is getting a close-up view of the innovation that propels race-boat design. But rarely do we get to report on radical concepts that work so well we’re prepared to shout their benefits from the masthead. Well, put in your earplugs because the Schock 40 has arrived.

It’s been 12 years since Tom Blackaller built a 12-Meter with fore-and-aft rudders. The twin-foil technology used in 1987 was the brainchild of DynaYacht’s president Charles Robinson. It was refined on the prototype Red Hornet by Dyna-Yacht’s design team of Matt Brown and Bill Burns. The patented Canting Ballast, Twin Foil system is now available in the 40-foot production sportboat from W.D. Schock Corp. I test-sailed the Schock 40 in San Pedro, Calif., during the Cabrillo Beach YC’s Winter Series and can report the new boat is light, narrow, and very fast.

The PHRF rating of -6 for wind-ward/leeward racing only begins to tell the story. I wouldn’t have believed it if I hadn’t seen it with my own eyes, but this 40-foot displacement boat beat an 18-foot skiff (sailed by Howard Hamlin) to the second weather mark in 12 to 15 knots of breeze.


The twin-foil arrangement isn’t the only innovation. A swing-ballast-bulb system reduces ballast requirements by 60 percent, and the boat’s displacement is only 7,000 pounds. The ballast bulb can be canted 55 degrees to either side, and with a push of a button you can fully tack the system in nine seconds.

Just so there’s no misunderstanding, this is not a canting keel–it’s a canting ballast bulb. The stainless steel foil supports the bulb, which provides the righting moment. The twin rudders provide lift and prevent leeway.

Steering downwind during one race, I was a bit surprised that the boat responded as it did. The two rudders are linked and work in opposite directions around the pivot point of the boat. I expected the boat to turn more quickly because of this, but it handled in a positive, responsive way without being overly sensitive. The rudders are mounted on stainless steel posts, faired with a composite covering, and supported by Harken rudder bearings. The tiller and rudders are linked by an Edson steering system.


The key is that the rudders act in unison, unlike Blackaller’s system, which featured two independent steering systems. The high-aspect foils have been wind-tunnel tested and feature a unique adjustment known as “the collective” that can change the foils’ angle of attack up to seven degrees, without moving the tiller.

For those concerned about sailing with the leading rudder exposed, DynaYacht says that the rudders are engineered to ABS standards with false tips (on the bottom 20 percent), and the rudder tube is housed in a crash box. The hull itself has an added 30-percent structural buildup in that area.

According to co-designer Brown, the technological advantage of twin foils goes beyond advanced steering and leeway prevention. If you look at drag models of a typical sailboat, you’ll see a high-pressure area in front of the keel. The front foil dampens this bow-wave effect.


The swing-ballast system uses an hydraulic ram powered by an electric motor to position the ballast. Cockpit buttons allow the helmsman to adjust the ballast to level the boat, and a cabin-mounted indicator shows the exact angle of the bulb. The electric motor and servo-mechanism are powered by a bank of 6-volt batteries, separate from the 12-volt house system, and will provide power for 48 hours without recharging. If necessary, a manual override can pump the bulb into position. The hydraulic unit is tucked behind the nav station, which swings out for easy access, and the battery bank is positioned on the opposite side to keep the boat in trim.

Two large transverse frames extend to deck level and support the ballast mechanism between them. According to Schock, the composite hull construction is built to ABS standards using vinylester resin and knitted E-glass fibers over a 1-inch PVC foam core, with balsa core reinforcing the high-load areas. Chainplates are of monocoque design and are glassed to the hull/deck flange. Toerails are molded in the deck forward of the mast only; the entire deck is glued to the hull flange.

The Schock 40 sports a nice but spartan interior, including a fully enclosed head. A wide, stainless, two-step companionway ladder gives easy access to the cabin. Midship settees double as berths with storage areas underneath. The cabin is roomy, has stand-up headroom, and the six smoked-glass sidelights provide plenty of light. A hanging locker and cubbies offer ample space for crew gear. Stainless tubes that serve as conduits for the internal mainsheet system also act as handholds.


The large cockpit was developed with input from America’s Cup veteran Peter Isler (and for purposes of full disclosure, a Sailing World Editor at Large). Says Isler, “I campaigned the prototype, Red Hornet, for two years. The Schock 40 is incredibly fast, easy to sail, and fun. You feel like you’re David beating up on Goliath when you race the boat–it’s that fast.”

Aside from Isler’s contribution to the layout, his Red Hornet campaign (see Speed by Design, Dec. ’97/Jan. ’98) established the boat’s PHRF rating basis across the country. With the sixth production hull about to splash, a one-design class could develop. Previously, racing around the buoys was not very realistic in canting-ballast boats because of the time it took to shift the ballast during a tack. The Schock 40’s relatively quick system solves the problem.

The boat comes standard with a keel-mounted carbon-fiber Omron mast and adjustable mast step. The swept-back triple spreaders are angled to support the rig without requiring runners, checks, or a backstay, although all three are provided for optimal sail shaping. Discontinuous rod rigging and an aluminum boom complete the rig. Non-overlapping jibs and an asymmetric spinnaker on a 6-foot retractable sprit make up the sail plan.

The boat I sailed, Nick Martin’s On Point, was treated with an optional CopperPoxy anti-fouling barrier system. Schock puts the copper flakes right in the mold. With an estimated life of 10 years, the CopperPoxy system gives drysail performance in a hard, durable, anti-fouling finish.

Viewing ports for each foil and a special kelp removal system come stock on the boat. Another nice feature is the engine well. The current trend is to put the outboard in a cockpit well to eliminate the drag of a prop by hoisting the engine up, yet still have the throttle controls, charging system, and internal fuel tank of an inboard. On the Schock 40, the engine actually retracts in a vertical position, and a plug is fitted into the opening to minimize turbulence. Martin’s 15-hp, 4-stroke Honda outboard pushed the boat along easily at 8 knots.

For the two Cabrillo races we sailed, one inside the breakwater and the other outside, the breeze built from 6 to 18 knots. We had eight crew on board, and by the end of the second race we were all on the weather rail. We probably would’ve depowered if the wind had reached 20 knots. One of the best parts of the racing was going downwind; the ballast rolled the boat to windward to expose the asymmetric and give us a deeper angle. Maybe that’s why a suggested PHRF rating for the boat on more triangular courses is -21. In any case, with its simple layout, a crew of five or six could easily race the boat in moderate winds.

One last comment about the stability of the boat and ballast system: while driving between races in 12 knots, I canted the ballast to leeward. The boat simply heeled as if the crew had moved to leeward in light-air conditions, nothing more.

With the addition of an optional generator, the boat is capable of moderate distance racing, and at a base price of $190,000, sailaway condition for $210,000 is realistic. I was hard-pressed to think of many changes or additions I’d want on the boat. My list was short, but included treating the metal backing plate that supported the ballast mechanism with some red lead. While this was stainless steel, it had been heat tempered and lost a little of its stainless properties and weeped rust into the shallow bilge. I’d add more handholds down below, especially near the main hatch, and would either remove the stove or add a cutting board cover to keep the burners from snagging anything. On deck, I’d add a large supply of sedatives because you’re definitely going to get excited driving this boat.