Is this the future of sailing? The Eagle Class 53 is a wingmasted cruising catamaran designed to fly on T-foils

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Not everything that flies is destined to scorch around an America’s Cup course. The future for sailing hydrofoils is surely about more than just racing. At least, that was the view of one owner who, having witnessed the America’s Cup foiling catamarans, saw a big opportunity.

“I’ve worked as a skipper for yacht owner Donald Sussman for 16 years,” says Tommy Gonzalez. “When he saw the foiling Cup boats he knew that this was what he wanted to have a go at. He is not interested in racing himself, he wanted to go cruising, but cruising on foils. He saw what had been created and believed that this had practical potential. Put simply he said: ‘I want one and I want to be the first.’”

As well as being a professional skipper, Gonzalez is the president of Fast Forward Composites, a Rhode Island-based composite building facility where the Eagle Class 53 was constructed. Understandably, the road to creating such an ambitious cruiser was never going to be straightforward. So the plan was structured around several key elements and stages, starting with an efficient and easily managed wingmast.

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The hybrid solid wing and soft sail configuration means the rotating rig can be reefed. The entire solid wing can be rotated through 360° ensuring the rig can always be fully depowered – important for docking and close quarters manoeuvring

Of those two criteria, efficiency is easy to satisfy – wingmasts are by definition more efficient. It is the practicalities of handling them that usually causes problems. Reducing sail in breezy conditions and leaving the wing up at the dock are two of the biggest issues.

The solution on the Eagle Class 53 was to create a composite wingmast where 50% of the area is a solid D-section and the trailing 50% a soft sail that can be raised, lowered and reefed. Interestingly, it is a similar concept to that of the next generation of 75ft foiling monohull Cup boats, currently under development. “The rig is a little lighter than a conventional mast and sail set up, and significantly easier to handle,” explains Gonzalez.

“Because the sail can be raised or lowered we can reef the main, or even just sail with the solid section. The mainsheet loads are around 40% less than a conventional rig and because the sail can turn 360° we can let the wingmast fully rotate, which makes life simple when you’re docking. You just let it feather.

“In addition, because we have a part soft sail, which we have developed with North Sails, we can create twist which allows us to de-power the top of the sail, so we have plenty of control over this wing and the advantages that go with it.”

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Stage two

The next stage was to work towards foiling. To do this the team decided to create a cat that had C-section daggerboards that would help reduce displacement at speed but not lift the boat entirely. Getting used to controlling the power and feeling the behaviour of the boat through various wind ranges and sea states would provide a solid understanding of the boat’s characteristics.

“Once we have got used to the way the boat handles, the next stage will be to fit T-foil rudders which will take us onto the next level,” continues Gonzalez. “With these we will be able to get used to the software system, the instrument displays and the feel and the control of that part of the programme without taking the boat to full flight.

“That will allow us to get her up on her toes like a ballerina and keep her there so we understand what she feels like before she flies. “After that, in the spring next year, we’ll remove the C-foils, put on the T-foil daggerboards with their elevators, and move on to full foiling.”

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The wingmast has a solid D-section and trailing soft sail

The proposed T-foil daggerboards will be angled out which makes the overall platform slightly wider, which in turn makes for more stable and efficient foils. And while improving the efficiency of the lifting surfaces, the outward bend in the daggerboards will also help to generate more righting moment, and hence achieve greater stability.

The control system itself will be a form of fly-by-wire system that will allow autonomous flight to ensure that the boat sails within safe operating limits. “If you have some of the gods of sailing aboard you will be able to override the controls to some degree, but under normal circumstances the control system will automatically de-power and lower the boat back into the water when the speed gets to 35 knots,” he explains.

Early days

So far the project has gone well. After the boat was launched earlier this year she cruised in the Caribbean during the regatta season before heading north back to Bristol, Rhode Island. “We’ve been very pleased with how well the boat sails and how easy she is to handle,” said Gonzalez.

“When we’re on delivery trips we have just three aboard. Aside from myself, the other two crew are not highly qualified professional sailors and yet we are looking at boat speeds of around 15-18 knots upwind and then 22 knots off the wind.

“We have also been through a squall of 35 knots where we were sailing with just the D-section of the wing mast which was easy to control by feathering the wing. When we get to the foiling stage we anticipate that we will be able to fly in around 10 knots true.”

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The Eagle Class 53’s roots lie firmly with the foiling America’s Cup catamarans. Even in displacement mode she’s an exhilarating ride. The goal is to achieve fully foiling performance

It is still early days for a project that Gonzalez describes as being “crawling before walking, before running and ultimately sprinting”, once the hydrofoils are fitted.

Yet during the development process it has become clear that there are others who are interested in the 53-footer, whether it foils or not. So, while the next big goal is to work towards building a 75-80ft long distance cruiser, currently called the 8X, interest in the Eagle Class 53 has been sufficient for the company to tool up for a limited production run.

“We have created carbon tooling for the 53 and are looking to build around seven of them,” said Gonzalez. “For the 8X, we are hoping to build three with the first being available during the winter of 2021-22.”

Gonzalez is a realist when it comes to the future. “As we all know, foiling has been around for a long time in military and public transportation, so we need to set an example to insurance companies and the likes that we are foiling safely and encourage others to follow. But the time has come. This is part of the evolution of our sport.”

Specification

LOA: 16.50m (54ft 2in)
LWL: 16.08m (52ft 9in)
Beam: 8.50m (27ft 11in)
Draught: 0.41m-3.05m (1ft 4in-10ft 0in)
Displacement (light ship): 6,000kg (13,228lb)
Displacement (max load): 7,540kg (16,623lb)