Winging It

Dear Doc,

We have recently added a new boat to our boathouse, a wing-rigger sweep boat. Two questions: Why wings in the first place? They are a hassle to rig with the nuts underneath the rigger. People keep dropping them. And just try adjusting your footstretcher when the wing blocks easy access to the nuts you are trying to get at. I know that side-mounted riggers are becoming extinct, but what exactly are the advantages of a wing?

Secondly, why are there so many holes to mount them? I understand that you can move the rigger fore and aft, but why would I want to do that? What should I look for when I set the boat up and then watch it on the water? It almost seems like there are too many choices. A violation of the KISS rule of engineering [Keep it simple, stupid].

Thanks. 

Sign me,

Too Many Holes.

I sympathize. We all have too many choices in our lives. Last night, I went to my favorite burger joint and had to decide whether I wanted cheese, crispy fried onions, banana peppers, chili, bacon, a fried egg (?), jalapeño aioli—the list goes on. But would you rather have your options be just ketchup and a boring sesame bun? 

We’ve got several winged boats in our boathouse, and at first glance some of the downsides you mention seem significant. We travel with a couple of boxes of extra washers and nuts. It does bother me that I often have a choice between putting the washers and nuts on blindly or bending so low that my back screams at me. 

Where did wing riggers come from? Most people credit Ted Van Dusen of the eponymous sculling boats as the father of the wing rigger. I called him up and asked what led him to develop the first one in 1984. Had he been inspired by a blue heron? Of course not. He’s an M.I.T.-trained engineer and very practical. In response to the adoption of minimum boat weights by FISA (now World Rowing), Van Dusen faced a dilemma. His singles and doubles were under the minimum weights. He wanted his boats to meet the new minimum standards so that they could be raced in big regattas, but he didn’t want to make his hulls heavier and slower. Instead, he made wings that were heavier than side-mounted riggers, thereby adding to overall weight. Voila! His hulls could continue to be very light. 

Another concern was that he had always questioned how aerodynamic conventional riggers were. He used the M.I.T. wind tunnel to measure drag and found that wings had 0.9 percent less drag than conventionals. 

“I knew that even my early wings felt better under bridges at the Head of the Charles when I rowed through wind,” he said. “I could get a foot more glide per stroke.”

I reached out with your questions to the friendly folks at HUDSON. Here’s what Dan Bechard, a biomechanist in their engineering group and the men’s coach at Western University in Canada, had to say: “Wing riggers have improved in many ways in the last 40 years. They are lighter and stronger. They offer more adjustability.” 

Compared to side-mounted riggers, which had to have ribs for mounting, the wings offer greater torsional stiffness. “The old boats, especially the old wooden boats, would flex at the catch and finish. You could feel it.” The wing’s design enabled boatbuilders to get rid of the ribs; a boat with wings across the hull is much stiffer than one with ribs.

“There’s another advantage; it gets the rigging above the waterline. Everything is on top of the gunwales. In windy conditions with waves, it lessens the chance that the riggers will catch water.” 

And the holes? They allow adjustability and enable a crew to get the right trim, balancing the weight bow to stern. “Getting the right trim is critical for the shell’s drag profile. Too bow up or down can create excessive drag, hindering performance. Moving the rigger can help you attain the ideal trim and maximize the performance of the shell at race rates. If the rigger changes positions, the footstretcher should also change position by an equal amount and in the same direction. Coaches should always feel welcome to contact the manufacturer for guidance.”

Wings have gotten lighter since Van Dusen’s original productions. Now, there is a weight savings by having a wing. That means that more weight can be put into the hull in the form of more carbon fiber. That makes the hull stiffer.

I checked in with Mike Davenport, best known for his books on rigging, but also a longtime coach at Washington College in Maryland and a former boatman for the U.S. National Team. He likes the rigidity and stability that wings offer. “Stiffness is critical because it reduces the lateral torque. Over the years, a boat with wings will stay stiff.” 

There’s another thing he likes about them. “We row in very rough water, and the extra clearance by having the rigger all above the waterline is great. But inside the boat, there is less clearance—witness the smashed fingers on wings. It’s a biofeedback loop; it teaches rowers not to drop their hands at the catch or OUCH!”

Negative feedback works.