Cruising the Eagle Class 53

Sailing at 19 knots in 15 knots of breeze is not an earth-shattering experience anymore. I was thinking about that on a perfect late summer day in Narragansett Bay while we were slicing along on the most technologically advanced cruising catamaran I’ve ever seen—the Eagle Class 53. This sculptural, cool silver machine with its concave hardtop, sprawling red lounge and clear-coat carbon bar area was created to fly on hydrofoils controlled autonomously by sensors and algorithm-driven computer software.

“Here comes the puff,” called the boat’s captain, Tommy Gonzalez, from the windward steering station. “Ease out just a bit.” I was at the control island, right up front, just behind a compression post under the hardtop, trimming the soft, battened aft “flap” of the hybrid wing sail. The forward edge was a silver-painted solid wing straight out of the America’s Cup, controlled by a single “restrictor” line.

We accelerated quickly and smoothly into the low 20s, but we weren’t flying. Those foiling daggerboards were not created yet—the Eagle Class’s multi-stage design process creates both a “skimming” version with arching “C” foils, and the EC 53 Sport, a fully autonomous foiling version with articulating “T” foils. This is meant to be the first luxury sailing foiler on the market, a holy grail of sorts in the sailing industry. The design brief: get there fast, without spilling a drink, and entertain in style.

And it was working. The same independent digital system that was developed to control flight for the EC 53 Sport was controlling the rudder elevators, or “T” foils. And the wing sail, with its smaller two-element arrangement, had low loads and was easy to hoist, douse and trim. The key takeaway that day was that, even though we weren’t ripping around with our hair on fire, we were going fast, the boat was flat, and remarkably, when that 21-knot puff hit the small jib and wing sail, the windward hull never lifted. In fact, it was the leeward bow that lifted slightly. Even a large motorboat wave could not pitch or roll us.

Maybe, just maybe, Gonzalez, the boat’s owner, Donald Sussman, and designer Paul Bieker, along with builders Fast Forward Composites have cracked the code and created the first working, large, autonomous recreational foiler. They may have also stumbled upon a platform solution that solves all the negatives of catamaran sailing: hobbyhorsing and capsizing.

Gold Ring of Foiling

Over the years they’ve done it in small sail and powerboats. They’ve done it in windsurfing. They’ve done it in surfing. But no one has yet produced a luxury sailing foiler that will consummate the sailing universe’s love affair with hydrofoiling. Sure, Timbalero3, Gunboat’s blood-orange 40ft G4, set the sailing world on fire in 2015. “Man, that thing’s awesome,” was the collective cry, at least until the chinks in the armor—reliance on mechanical flight control and expert, precise helming—were revealed in a not-so-violent, but all together deflating capsize during a Caribbean photoshoot.

Though the 2013 America’s Cup, with it’s foiling 72-footers, broke new ground in the sport of sailing, transference of that image into luxury yachting has taken longer than expected. Granted, there are now around a dozen production sub-25ft sailing foilers on the market. Many of these are also multihulls, including the U.S.-manufactured UFO, a real toy in every sense of the word. Small boats, however, are easy to prototype and require only a fraction of the investment in order to go into full-on production. They also represent an entirely different kind of sailing, the key distinction being that in luxury sailing, the participant isn’t looking to get wet.

Last summer was my chance to see if the golden ring of luxury foiling had finally been grasped when I sailed aboard the EC 53. My impressions were more than positive. I loved it. Even without fully foiling, the raked C foils added so much lift that when the puffs went into the 20s, the leeward hull began truly skimming the surface. More puff, more lift and the rudder elevators kept the bows from pitching down as the pressure increased. The rudder flaps can also be autonomously articulated to react to the pitch of the boat when we sailed over or through larger wave sets. For our trip, Gonzalez was pre-setting them digitally.

Down below there are two mirrored cabins, one in each hull. Decadent for a couple, for sure, but it’s the sprawling area between the hulls where the owner’s experiences are focused. And that area is open all around. There’s no windshield and when sailing along at 20 to 25 knots, it’s loud upfront. In the bar and all the way aft, though, it’s surprisingly serene, dramatically quieter and easy to have a soft conversation as the mist of flat white water streams off the transoms. It’s this and other sailing sensations that Sussman had wanted to cultivate in the Eagle Class, foiling or not.

Designing and Engineering Smoothness

It’s strange that many multi-million dollar custom yacht projects complete all the boat’s trialing on a computer. After that, the boat is built, sails and rig are installed and good luck to you. Sussman knew he was biting off a lot when he asked Bieker, a lead designer for Oracle Team USA in the 2013 Cup, to design an autonomous foiler. As an investor in people from R&D programs for algorithmic trading shops, he knew the boat must be developed in multiple stages. Why? “Because we wanted it to work,” he says bluntly.

“You have a beginning and a goal, but you don’t know the speed bumps,” says Sussman, who had designer Pete Melvin create a 90ft catamaran for his last boat. Sunshine was the name and she was a 90-footer because at that length she was able to span the average wave period of the Caribbean, where Sussman enjoyed sailing and entertaining. “The offensive thing in catamarans is the hobbyhorsing,” he says. “It’s nauseating and so unlike what you’re used to. The smoothness we designed into this boat is very important to me in terms of how you want to experience sailing.”

Sussman, like many, was inspired by the 2013 Cup races, and he found Bieker through Melvin, who had authored that Cup’s design rule. When he figured out he couldn’t make Sunshine foil—“Everything about the loads is downward. In hydrofoils, the loads are going up”—he had Gonzalez set to work putting together a team to create what is now the EC 53.

A New Concept

Paul Bieker was at the dawn of foiling in the Cup and furthered his experience working on the designs we saw having fully “dry” laps, hulls never touching the water, in the 2017 Bermuda America’s Cup. The EC 53 was a chance to apply some of what he learned to a recreational boat.

“We always had the boat in two configurations, C foils and T foils, in the design stage,” says Bieker. To foil, or just skim, the boat needed to be ultra-light, even though it isn’t meant to race. “The majority of outfits don’t work the engineering as much as they could. Especially when you use high-temperature cured, pre-impregnated laminates, they’re pretty magical. You can do something pretty special.”

Bieker said this engineering is critical to the success of a boat like the EC 53. “If you are not careful in your engineering, that 20 percent extra weight, the cost is higher than you think. The loads go up the heavier you get. It’s the opposite the lighter you go. In either direction, it’s a reinforcing loop.”

All aspects of a foiler must be precise to work. But the secret sauce for any foiler is the flight-control system. For most foilers, controlling the articulation of daggerboards and rudder flaps is a mechanical procedure, involving manually controlled pulleys and line or hydraulic rams. The EC 53’s system is autonomous, with electric motors, cameras and myriad sensors connected to a computer that controls the foils. A proprietary system (for now), the EC 53’s flight controller will be put to the test in the spring when the new T foils are built and tested in the Caribbean.

“It was an eye-opener in Bermuda,” says Bieker, referring tacitly to the virtually autonomous flight control system used by the winning New Zealand team. “These were the first truly fly-by-wire boats. There’s a network around the boat, devices are connected. The computer monitors the network and interacts with it. The way you control it is a matter of programming. There’s a lot of potential for making systems that can do things we haven’t done in the past.” He adds that without systems like this, Cup teams in Bermuda would never have mastered full-foiling tacks.

“The boat is conceived to be fully foiling,” says Bieker. “But I think there is a lot of potential in using the elevators pretty actively in non-foiling.” He says that a differential between the windward and leeward rudder elevators—having them at different angles—is something he learned to use on the Cup boats and has employed on the EC 53. Not only can this differential add down-force to the weather hull and lift to the leeward one, it can also counter pitch and roll to make for a more level ride in most sea states.

Bieker agrees with Sussman that a two-stage development cycle was necessary. “The rig was enough of an experiment to concentrate on during that first stage,” he says.

The hybrid wing sail is not new, and not without its critics. A C-Class catamaran sailor from the old Little America’s Cup pointed out for me all the failed hard wing-soft sail combinations over the years. Nonetheless, it also solves a significant problem with hard wings, that they’re

up all the time, while eliminating the weight of large, heavily battened soft sails.

The wing element on the EC 53 is tall, with a very short chord (fore and aft) length. It’s controlled by one line and once the soft sail element is removed, that line is detached. Because of the ultra-wide shroud angles, and the short chord length, the wing calmly rotates 360 degrees, producing no lift. As for the soft sail, it has a complex but robust track system that allows the batten cars to be removed easily as the sail comes down. Since it too has a small sail area, it takes only one or two people standing on the hardtop to hoist or douse.

“There’s no question the hybrid is inferior to a solid wing sail,” says Bieker. “But I believe it’s much more efficient than a soft sail with a standard wing mast.”

Unfortunately, we found it a challenge on our test sail to make the leeward surface of the wing sail a constant curve. Facebook posts showing images of double convex curves on the leeward side of the sail drew sharp criticism, and Gonzalez and Bieker agree there is some development left. “That said, it’s working pretty darn well,” says Bieker. “It’s a safer rig than you think.”

Why not Stop Here?

The Eagle Class is being offered for sale as a production boat in the two versions. Next spring will be the proving ground for the sport version, and both Sussman and Bieker already believe they are on to something.

“If we did nothing now, it’s incredibly poised and balanced,” says Sussman. “That’s because we took it one step at a time. It’s a real question whether we shouldn’t leave it like this.” He also relates some experiences he’s had sailing around densely populated areas where, even at 15 knots, “it’s a challenge not to run people over.”

As it is, the EC 53 Sport will likely easily be able to reach 35 knots, and Bieker sees even more potential in using the control system technology outside of foiling. “I’ve thought there’s a lot of potential to use the rudder elevators pretty actively in non-foiling,” he says.

Bieker says he is still hooked on the foiling sensation.“I think it will always be a specialized niche,” he says, adding that there’s nothing else like the EC 53. “It will get easier and easier. But it’ll be a long time before it’s trivial. When you’re going 35 knots, it’s a pretty lively process not to be taken lightly. But it is pretty magic. When we started flying the 72 in San Fran, up on the foils everything would quiet down and move over the water so silently. You feel the acceleration and forces much more clearly.”

As for Sussman, he says he too is happy where he is at the moment, with the EC 53 slicing along around the Hamptons, the Caribbean, Newport and Martha’s Vineyard. “This is like owning a sports car,” he says. “There are two lovely cabins, a full galley. For me, it’s more fun to catch an afternoon with a nice wind, race around then go home.” The biggest tip Sussman has for anyone who wants to sail the EC 53: It’s not good to eat sandwiches. It’s better to eat wraps. Otherwise, the bread and lettuce go flying. 

Photos by Rachel Fallon-Langdon

November 2019