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Windrocket

2000 August 7

Multihull speedster

When I was 15 years old my dear old Dad dropped me off at Bill Garden's office early one Saturday morning. I had a nice visit with Bill and left with an armload of old prints and a box full of magazine cutouts that went back to the '20s. I think someone had dumped the box on Bill and he just wanted it out of the office.

That box contained article after article of radical and innovative sailboat designs. The history of sailing is rife with exotic approaches to sailing fast. Most die an agonizing and slow death on the beach after their first sail trial. In some cases the radical designs just didn't work. In other cases the sailing public watches the experimental craft whizz by and says, "So what?"

Still, just look around and you'll see that the quest for speed under sail is alive and well and may have nothing whatsoever to do with market acceptance. There are designers like Ken Fry of the Windrocket program who are convinced the sailing world is waiting for a way to go faster, easier.

In the last couple of years we have seen the TriFoiler make some market headway and the foil-borne Rave has seen some acceptance. I have seen the Rave out in Seattle, but I have yet to see it rise up on its foils.

The primary problems with this approach are complexity and wetted surface. You need a healthy breeze to get these foil-borne boats to take advantage of their foils and break loose. If your area is like Seattle, you can count on 7 to 8 knots with gusts to 13 knots on most summer days. Foils aren't going to be much fun in these conditions. In fact, glued to the water in 5 knots, the foil-borne boats can be clobbered by a good monohull dinghy like a Tasar, International 14 or the exceptional 49er.

Ken's unique approach uses a narrow, planing center hull and two buoyancy pods at the end of 10-foot winglike akas. Max beam is 20 feet. The Windrocket will need to be sailed dead flat so that the pods do not create drag.

The Windrocket is still in the prototype stage and hull No. 1 has not been sailed yet. It has, however, been motored with a small outboard and the designer says that it must be sailed balanced on the center hull. I'm skeptical. I just can't see keeping this craft with its 20 foot wingspan balanced on a 30-inch-wide center hull in light air. Of course, in a breeze it will be easier to keep the hull balanced, but I wonder about dipping the leeward ama and perhaps even dipping portions of the leeward aka. What happens during a tack or jibe?

The rig is a solid wing with a flap, and an endplate and midpoint "fence" to help keep the flow attached. If the boat heels over to rest on one of the pods while docked, the wing sail will swing to leeward and develop some angle of attack. Upright, the wing will just cock to weather. To prevent the wing from swinging over, a 30-pound weight has been added to counter the weight of the wing. The pivot point of the wing is at 20-percent chord.

All-up weight of the Windrocket is projected at 300 pounds. The wings pivot around 90 degrees for trailering. Ken is very optimistic. He sees people dumping their jet skis and buying Windrockets in droves. What a thought. I hate to be a curmudgeon, but I have seen a lot of experimental craft come and go, which has given me a "build one and show me" attitude. It's one thing to envisage this boat screaming along in perfect balance in the middle of the bay, but there are other areas that need to be equally as gracefully conquered, like docking. Windrocket was scheduled to undergo sea trials in mid-June.

I wish Ken the best of luck and all the success in the world.