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“iFLY15 is the unique combination of high performance with easy accessibility – for maximum performance and maximum fun.”

Cec catamarans -ifly15 team, “we love speed while keeping control – high speed needs to be controllable. the flying boat of the future, is a stable foiling sport catamaran.”, cec catamarans – ifly15 team, „ foiling: one of the things you have to experience to really feel it. “, jimmy spithill, skipper oracle team usa, “stable flight is the key to high performance sailing”, “ifly15 – get the balance right between a nice sporting challenge and a reasonable and controllable level – enjoy the exhilaration, the speed and the adrenaline in your veins, but always stay master of the situation “, “stable flight attitude is the most important prerequisite for high performance sailing.”, victor diaz de leon, sailgp team usa, “stable flight attitude is key for easy foiling. ifly15 with superior flight stability delivers immediate flying fun within the first minutes. advantage through high-tech.”, “the ifly15 is the quickest boat around the course, … “, arno terra – sailor, ifly 15 one design and ifly razzor pro, the  performance  foiling  catamaran, for maximum speed and maximum control.

• Easy access to a high HIGH PERFORMANCE FOILING CATAMARAN
• Automated DYNAMIC FLIGHT Assistance SYSTEM – FLYSAFE® FOIL CONTROL
• highest quality standards – High-tech full carbon sailboat
• completely modular – fully customizable
• adjustable rake – MAIN FOIL DIFFERENTIAL during sailing for even more performance in the version IFLY Razzor Pro
• Foiling Versatility and Speed …

The quality and performance have been proven for 8 years and further developed to maximum perfection in every detail

IFLY HYDROFOIL SAILING – EXCELLENCE, FIELD PROVEN TO PERFECTION

Racing     and     more   …..

⦿ Have a high performance racing machine on regattas

⦿ single handed or double Foiling

⦿ crew weight up to 180 kg

⦿ Racing and fun:

⦿ Sail with Family & friends

in any sailing condition:

⦿ Full foiling – upwind and downwind

⦿ Waves and Flat waters

⦿ Light and strong winds

⦿ early take off

⦿ Foiling maneuvers

Transport and Facilities

⦿ Easily transportable on a road trailer

⦿ Slipped with a conventional beach trolley

⦿ ready to sail in 20 minutes

⦿ iFLY15 is designed to sail on the sea and lakes

Stay tuned for foiling events and specials!

Flysafe® Flight assistance

Main foil differential technology – mdt, innovative, sophisticated foil control for unbeaten performance, high speeds and easy access, ifly15 and ifly razzor pro, ifly main foil differential – mdt, ifly razzor pro.

early take off in lightest breeze

F oiling maneuvers are heavily supported, superior flight attitude through active foil control, dynamic control of f light high , pitch and role, non-linear control and feedback control system for best flight stability, even in waves, the foils do not need to be manually manipulated, optimized performance: advanced sailors can adjust rake and gearing, more about flysafe®>>>, active flight assistance, the foil can be trimmed actively while sailing, the key to maximum performance , mdt for performance-orientated pro sailor, mdt extends the flysafe® foil control, to sail large xxl rigs, more about main foil differential ->>>, performance downwind: staying on the foils, full foiling, in 5-6kts tws, reaching max. boat speeds of up to 2.5*tws, performance upwind: full foiling from 8kts. tws, taking off from 7kts tws, video youtube channel, ifly15 foiling catamaran.

The most innovative development in foiling technology

About ifly15, stable flight  is  key for both: first for highest performance and foiling in a wide wind range, including rough and wavy conditions, but also easy access into foiling…...

iFLY stands for uniqueness in design and function. Its superior Flysafe ® active foil control system autonomously supports the stable horizontal flight position in the longitudinal and lateral direction. The 4 T-Foils do not have to be operated by the sailor during sailing.

Average skilled dinghy or catamaran sailors with some trapeze experience can safely foil with the iFLY15 after only a few hours. Quick access – the immediate sensation of success – steep learning curve. In the hand of an experienced sailor, iFLY15 offers a whole new sailing experience with previously not experienced speeds and agile maneuverability.

The flight control system, combined with numerous fine-tuned innovations , ensures safe foiling even in strong winds and rough seas.. Stable flight attitude allows pushing hard, so in good conditions, iFLY reaches high boat speed beyond 30 knots in a controllable way.

IFLY15 offers freedom to fly alone or in pairs. Due to the exclusive use of high-tech materials , iFLY15 is extremely rigid and weighs less than 90 kilos ready to sail. With its low weight and its state-of-the-art hydrofoils, it is airborne in winds as low as 2Bft. / 6 Knots.

iFLY15 has a length of only 15 feet, is easy to transport, quick to get ready to sail, and can be easily slipped from the beach using a conventional beach trolley.

Its sophisticated design reflects the highest demands on quality and function.

iFLY15 – customer reviews

 « LESS CRASHING IS MORE FUN »

MARCUS LYNCH, PROFESSIONAL SAILOR AND OLYMPIC COACH, GC32 OMAN, NACRA17

« I WAS INITIALLY AMAZED AT HOW EASY TO HANDLE THE IFLY IS AND AT HOW IDLE THE BOAT IS EVEN IN STRONG WINDS. »

ANTOINE, IFLY OWNER FROM GENEVA

VERY STABLE, EXTRAORDINARY STABLE. IT IS EXTREMELY INTERESTING, BECAUSE YOU IMMEDIATELY SEE THE ACCESSIBILITY OF THE BOAT.

FRANÇOIS GABART

« GREAT BOAT, LIKE A MOTH ON STEROIDS ! »

VICTOR DIAZ DE LEON, MIAMI, PROFESSIONAL SAILOR. US TEAM SAILGP, INTERNATIONAL MOTH, MATCHRACING MELGES 32, J70

WHAT A GREAT BOAT THIS IS, AND I ABSOLUTELY LOVE IT”

PHILIP WALKER

« THE DYNAMIC FLIGHT CONTROL SYSTEM ALLOWS LONG AND STABLE FLIGHTS »

GERHARD FLORIN, IFLY OWNER FROM GENEVA, SWITZERLAND

TO FELLOW SAILORS WHO LOVE THE THRILL OF SAILING WITH SPEED WHILE MAINTAINING CONTROL”

ROY BALLENTINE

« WELL BALANCED AND RAKE DIFFERENTIAL ALLOWING FOR GREAT PERFORMANCE UPWIND! »

CARLOS ROBLES,PROFESSIONAL SAILOR 49ER, PALMA DE MALLORCA

« A SENSATIONAL FOILING EXPERIENCE. THE SPEED IS IMPRESSIVE »

INGMAR WARNICKE: COMMODORE OF YCSO, YACHT CLUB SCHARBEUTZ, BALTIC SEA

⭐ ⭐   ⭐   ⭐   ⭐

IFLY RAZZOR PRO – THE NEW IFLY FOR EXPERIENCED SAILORS

THE SINCE 7 YEARS PROVEN IFLY15 WITH FLYSAFE® DYNMAMIC FOIL CONTROL has now a pur Racing fellow: THE iFLY RAZZOR Pro. THE iFLY racing VERSION ENABLES EVEN HIGHER PERFORMANCE, to sail in extremely tough conditions and allows sailing with XXL rigs. THE MAIN DIFFERENCE BETWEEN THE IFLY15 ONE DESIGN AND THE IFLY RAZZOR PRO IS A BIGGER RACING RIG, SPECIAL FOILS AND THE MAIN FOIL DIFFERENTIAL (MDT), WHICH IS MANUALLY TRIMMED BY THE SAILOR. THE MDT IS WORKING HAND IN HAND WITH THE FLYSAFE® DYNAMIC FOIL CONTROL SYSTEM.

flying – sailing – Blog

“We’re taking off! Foiling is THE Watersports Trend! – „Boot International 2024“ in Düsseldorf / Germany once again showcases: Foiling is THE trend in watersports.

Performance Sailing – Sail GP News: Racing on the Edge – T-Foil proves to be the winning design

Regatta and foiling News: Long distance Race – Duc d’Albe 2023 – Club Multicoques Hyères – sailing Race @iFLY Razzor Pro

iFLY Main Foil Differential Technology – MDT Foil Control – high Performance sailing

IFLY FOILING Adventure

FOILING – REGATTA – EVENTS

Long distance Race – Duc d’Albe 2021 – Club Multicoques Hyères – sailing Race @iFLY Razzor Pro

INTERNATIONAL IFLY foiling FLEET RACE 2021

iFLY15 successfully crossing the English channel / world record Attempt Cowes to Dinard / Saint Malo

Catamaran europe central, the iflysail team, is looking forward to your message.

• (321) 878-3645

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Come Visit Us in Miami Feb 15 - Feb 19 - Sea Trials on the Hour

Come Visit Us in Palm Beach Mar 26 - Mar 29 - Sea Trials on the Hour

Experience the Game Changing Difference

Upcoming Sea Trial Events

• St. Pete Boat Show – (Jan 19 – 23, 2023)
• Miami International Boat Show – (Feb 15 – Feb 19, 2023)
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Unique Engineering

The foil assist.

• Ultimate Performance
• Patented Morrelli & Melvin Hull / Foil System
• Bespoke-built, Epoxy-Infused Hulls

The New Paradigm

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• Unlike Any Other Center Console on The Market

What People Are Saying

Why Foilcat?

The FoilCat Team is relentlessly dedicated in our pursuit of the ultimate user experience accentuated by the highest performance and safety standards throughout the marine industry.

A RIDE LIKE NO OTHER

The foil greatly improves ride quality and efficiency.  Reduction in operator and passenger injury and fatigue.

CUSTOMIZABLE

Built to suit from collars to cabin tops and the engines on the back. We work with you to create your dream watercraft.

IMPROVED RANGE

A greater range on same volume of fuel vs any other platform. Our models are 40-50% MORE fuel efficient than our market competitors.

WATCH: How do the F50 foils work?

SailGP’s high speed, foiling F50 is the culmination of 10 years of development in high performance, multi-hull racing.

The F50's cutting edge technology is evident in its status as the first boat to hit 99.94 km/h during racing - and it has a top speed of over 100 km/h.

But how does the F50 fly above the water and how to teams work together to get as much speed out of the boat as possible? The F50 foils using rudders with elevators and two daggerboards for a fast and stable flight.

The boards are constructed with higher modulus carbon fiber for less resistance at high speeds.

A number of technical innovations work to reduce the onset of cavitation - which occurs when the reduction of water pressure ‘boils’ the water around the foils - creating air bubbles which increase drag and reduce lift.

Teams must therefore work together to fly as high as possible without flying too high and crashing into the water, rising speed and losing speed in SailGP’s high pressure racing.

More from SailGP

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[2023] Hydrofoil Yacht: The Ultimate Guide to Sailing on Foils

• November 1, 2023
• Hydrofoil Basics

Quick Answer: A hydrofoil yacht is a sailboat equipped with wing-like foils that lift the hull out of the water as it gains speed. This reduces drag, increases speed, and provides a smoother ride. Hydrofoil yachts can be retrofitted on both monohull and multihull sailboats, with different types of foils used for stability and control.

Welcome to Hydrofoiling™, where we bring you all the latest and greatest information about hydrofoil boarding. In this comprehensive guide, we’ll dive into the world of hydrofoil yachts, exploring their history, configurations, classes, and more. Whether you’re a seasoned sailor or a curious beginner, this article will provide you with expert advice and insights into the exciting world of hydrofoil yachts.

Table of Contents

Quick answer, quick tips and facts, background: the evolution of hydrofoil yachts, types of hydrofoil yachts, hydrofoil classes: from moths to ac75, hydrofoil yacht brands and models, advantages and disadvantages of hydrofoil yachts.

• Recommended Links
• Reference Links

A hydrofoil yacht is a sailboat equipped with wing-like foils that lift the hull out of the water as it gains speed. This lifting action reduces the wetted area of the hull, minimizing drag and allowing the yacht to achieve higher speeds. Hydrofoil yachts can be retrofitted on both monohull and multihull sailboats, with different types of foils used for stability and control.

Shopping Links: Check out hydrofoil yacht products on Amazon | Shop hydrofoil yacht on Walmart | Etsy hydrofoil yacht products

• Hydrofoil yachts use foils to lift the hull out of the water, reducing drag and increasing speed.
• Different types of foils, such as T foils, C foils, S foils, and L foils, are used for stability and control.
• Hydrofoil yachts can be retrofitted on both monohull and multihull sailboats.
• The International Moth class is one of the most widespread uses of hydrofoils in sailboats.
• Hydrofoil yachts can achieve impressive speeds, with some reaching over 50 knots.

Hydrofoil technology has been around for over a century, with the first patent for a hydrofoil boat filed in 1898 by Italian engineer Enrico Forlanini. Since then, hydrofoil yachts have undergone significant advancements, transforming the sailing experience and pushing the boundaries of speed and performance.

The concept behind hydrofoil yachts is simple yet ingenious. By using wing-like foils mounted under the hull, these yachts can lift themselves out of the water as they gain speed. This lifting action reduces the wetted area of the hull, minimizing drag and allowing the yacht to glide effortlessly through the water.

Hydrofoil yachts come in various configurations, each designed to optimize performance and stability. Let’s explore some of the most common types of hydrofoil yachts:

Monohull Hydrofoil Yachts : Monohull hydrofoil yachts feature a single hull and employ a “ladder” arrangement of hydrofoils. These hydrofoils typically have a dihedral angle of around 50 degrees and are complemented by a stabilizing rudder foil. This configuration provides stability and control, allowing the yacht to sail smoothly on foils.

Multihull Hydrofoil Yachts : Multihull hydrofoil yachts, such as catamarans and trimarans, offer increased stability and performance. These yachts use wider planforms, allowing for greater lift and control. Some multihulls utilize three foils, with two main forward foils providing lift and a horizontal foil on the rudder for additional control.

Hydrofoil Catamarans : Hydrofoil catamarans, also known as foilcats, combine the stability of a catamaran with the speed and efficiency of hydrofoils. These yachts can achieve impressive speeds while maintaining excellent stability, making them popular choices for racing and recreational sailing.

Hydrofoil technology has found its way into various sailing classes, revolutionizing the way we sail. Let’s take a closer look at some of the notable hydrofoil classes:

International Moth : The International Moth class is one of the most widespread uses of hydrofoils in sailboats. These single-handed dinghies feature foiling capabilities, allowing sailors to achieve incredible speeds and maneuverability. The class has seen rapid growth since 2001, with carbon fiber foils and advanced design techniques pushing the boundaries of performance.

Waszp : The Waszp class is similar to the International Moth class but utilizes aluminum foils instead of carbon fiber. This makes the Waszp more accessible to a wider range of sailors while still providing the exhilaration of foiling.

AC75 : The AC75 is a foiling monohull sailboat class used in the 2021 America’s Cup. These impressive yachts can reach speeds of up to 50 knots, showcasing the incredible potential of hydrofoil technology in the world of competitive sailing.

IQFoil : The IQFoil windsurfer class was selected by World Sailing for the 2024 Summer Olympics. These windsurfers feature hydrofoils, allowing athletes to glide above the water and achieve impressive speeds.

IMOCA 60 : Originally designed as non-foiling offshore racers, the IMOCA 60 class has embraced hydrofoil technology. These yachts now feature S-shaped daggerboard foils, providing partial foiling capabilities and enhancing performance in various conditions.

F50 : The F50 sailboat class is used in the SailGP series and is the first sailboat class to break the 50-knot barrier during a race, with a top speed of 52.2 knots. These high-performance catamarans showcase the incredible speed and agility that hydrofoil technology can offer.

Several brands have embraced hydrofoil technology, offering a range of hydrofoil yachts to cater to different sailing preferences. Here are some notable hydrofoil yacht brands and models:

Gunboat : Gunboat is a renowned brand in the world of luxury hydrofoil yachts. Their models, such as the Gunboat 68 and Gunboat 72, combine performance, comfort, and elegance, providing an exceptional sailing experience.

GC32 : The GC32 is a hydrofoil catamaran designed for high-performance racing. This foiling catamaran offers thrilling speeds and precise control, making it a favorite among competitive sailors.

AC72 and AC45f/AC50 : These hydrofoil catamarans were used in the America’s Cup, showcasing the cutting-edge technology and innovation in the world of hydrofoil yachts. These yachts pushed the boundaries of speed and performance, captivating sailing enthusiasts worldwide.

Nacra 17 and Nacra F20 : Nacra is a well-known brand in the world of multihull sailing, and their Nacra 17 and Nacra F20 models feature hydrofoil capabilities. These yachts offer a perfect balance of speed, stability, and maneuverability, making them popular choices for recreational and competitive sailing.

Hydrofoil yachts offer a range of advantages that make them appealing to sailors seeking speed, performance, and an exhilarating sailing experience. However, they also come with some drawbacks. Let’s explore the pros and cons of hydrofoil yachts:

Advantages:

Increased Speed : Hydrofoil yachts can achieve impressive speeds, thanks to reduced drag and increased lift. This allows sailors to cover more distance in less time, making hydrofoil yachts ideal for racing or simply enjoying the thrill of speed on the water.

Smooth Ride : By lifting the hull out of the water, hydrofoil yachts provide a smoother and more comfortable sailing experience. The reduced contact with the water minimizes the impact of waves and chop, resulting in a smoother ride even in rough conditions.

Improved Efficiency : Hydrofoil yachts are more efficient than traditional sailboats, thanks to reduced drag and improved lift. This increased efficiency translates to better performance and reduced energy consumption, making hydrofoil yachts an environmentally friendly choice.

Disadvantages:

Complex Design : Hydrofoil yachts require a more complex design compared to traditional sailboats. The addition of foils and the associated control systems can increase the complexity of the yacht, requiring more maintenance and potentially higher costs.

Learning Curve : Sailing a hydrofoil yacht requires a certain level of skill and experience. The handling and control of a hydrofoil yacht can be more challenging compared to traditional sailboats, requiring sailors to adapt to the unique characteristics of foiling.

Higher Costs : Hydrofoil yachts, especially high-performance models, can come with a higher price tag compared to traditional sailboats. The advanced technology, materials, and design required for hydrofoil yachts contribute to their higher cost.

How fast is the hydrofoil racing yacht?

Hydrofoil racing yachts can achieve impressive speeds, with some models reaching over 50 knots (57.5 mph or 92.6 km/h). The F50 sailboat class, used in the SailGP series, holds the record for the fastest sailboat class, with a top speed of 52.2 knots (60 mph or 97 km/h).

What does a hydrofoil do to a boat?

A hydrofoil lifts the hull of a boat out of the water as it gains speed. This reduces the wetted area of the hull, minimizing drag and allowing the boat to achieve higher speeds. The lifting action of the hydrofoil also provides a smoother ride by reducing the impact of waves and chop.

Read more about “… Hydrofoil Catamaran: The Ultimate Guide to Foiling on Water”

How fast do hydrofoil boats go?

Hydrofoil boats can reach impressive speeds, depending on their design and purpose. Racing hydrofoil yachts can achieve speeds over 50 knots (57.5 mph or 92.6 km/h), while recreational hydrofoil boats can reach speeds of 20-30 knots (23-34.5 mph or 37-55.5 km/h) or more.

Why don’t boats use hydrofoils?

While hydrofoils offer significant advantages in terms of speed and efficiency, they also come with certain limitations. The complex design and higher costs associated with hydrofoils can be prohibitive for some boat owners. Additionally, the handling and control of hydrofoil boats require a certain level of skill and experience, making them less accessible to novice sailors.

Read more about “… Why do boats not use hydrofoils?”

Hydrofoil yachts have revolutionized the sailing experience, offering increased speed, improved efficiency, and a smoother ride. Whether you’re a competitive sailor looking for the thrill of high-speed racing or a recreational sailor seeking a more exhilarating sailing experience, hydrofoil yachts provide an exciting and innovative option.

Recommended Links:

• Hydrofoil History
• Advanced Hydrofoiling Techniques
• Hydrofoil Equipment Reviews
• How Do Hydrofoils Work on Boats? 2023

Reference Links:

• Sailing Hydrofoil – Wikipedia
• Gunboat Official Website
• Nacra Official Website
• SailGP Official Website
• America’s Cup Official Website

Now that you have a comprehensive understanding of hydrofoil yachts, it’s time to set sail and experience the thrill of foiling firsthand. Whether you’re racing on the high seas or cruising along the coast, a hydrofoil yacht will take your sailing adventures to new heights. Happy foiling!

Disclaimer: The information provided in this article is based on research and personal experience. Hydrofoiling™ is not affiliated with any specific brand or product mentioned in this article. Always consult with experts and follow safety guidelines when engaging in hydrofoil activities.

Review Team

The Popular Brands Review Team is a collective of seasoned professionals boasting an extensive and varied portfolio in the field of product evaluation. Composed of experts with specialties across a myriad of industries, the team’s collective experience spans across numerous decades, allowing them a unique depth and breadth of understanding when it comes to reviewing different brands and products.

Leaders in their respective fields, the team's expertise ranges from technology and electronics to fashion, luxury goods, outdoor and sports equipment, and even food and beverages. Their years of dedication and acute understanding of their sectors have given them an uncanny ability to discern the most subtle nuances of product design, functionality, and overall quality.

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Using a Hydrofoil to Improve Efficiency

• By Alan Jones
• Updated: July 15, 2021

It’s hard to believe a piece of metal with no moving parts can be the approximate equivalent of adding 200 horsepower, 100 gallons of fuel and 100 miles of extra range. But when it’s a hydrofoil attached between the hulls of an Aquila 36 Sport power catamaran (above, far right), that’s the net effect.

While the efficacy of foiling boats is well-documented, this technology has surprisingly had little impact on the recreational powerboat market. Hydrofoils that lift a hull entirely out of the water seem to be too alien to most boaters. Plus, most foil designs require dynamic control using computers to remain aloft at a constant elevation. But they are proven to be effective. With the Aquila 36 Sport, we experienced its benefits on a recreational boat and compared it in real time to the same boat without a foil but with 200 extra ponies. Here’s what we found.

Hydro What?

Gino Morrelli and Pete Melvin, of Morrelli and Melvin Design and Engineering, applied their decades of foiling experience to design the Hydro Glide Foil System for Aquila. It consists of a main hydrofoil attached slightly aft amidships to each hull and the top of the tunnel. It lifts approximately 40 percent of the hull’s weight out of the water when at cruise speeds, for better performance and fuel economy. Farther back, twin fins act like an airplane’s horizontal stabilizers to prevent porpoising at higher speeds. What makes hydrofoils so effective is the dramatic reduction in drag. A typical planing hull has a 4-to-1 lift-to-drag ratio, while a hydrofoil can have up to a 25-to-1 lift advantage.

How does it work? The fields of aerodynamics and hydrodynamics are kissing cousins, so many of the principles of one apply to the other. The silhouette of a typical asymmetric hydrofoil wing wouldn’t look out of place on a 737. It consists of a convex curve on the upper side and a flatter bottom side. These taper down toward the rear. Bernoulli’s principle explains that when air or water rushes over the top side of a wing, the medium has to travel farther, so it moves faster. This creates lower pressure on top, allowing the higher pressure on the bottom to push upward.

Sir Isaac Newton’s third law also applies to hydrofoils. The simplified version says that for every action, there is an equal and opposite reaction. So, if a foil is directing the water down, it’s pushed back and the foil rises, creating lift. This effect is enhanced by an increased angle of attack at the leading edge to create more lift. In the case of Aquila’s Hydro Glide foil, it will still provide lift even if the boat’s bow is pointing down 3.5 degrees, which will be useful when running down-sea because it avoids transforming the hydrofoil into the equivalent of a down-planer or sea anchor.

Too much lift can also be a problem, according to Alain Raas, brand manager for Aquila Boats. “Because water is denser, a hydrofoil creates about 830 times more lift for the same area and speed compared to an airplane wing, so you can use a much smaller foil in water than air,” Raas says.

Most hydrofoils operate near the surface and can ventilate, which is a phenomenon that occurs when the low-pressure side of a foil pulls air from the surface and destroys lift on the foil, Raas explains. “Foil depth, sweep, dihedral and section shape all play a significant role in avoiding ventilation,” he adds.

Dueling Aquilas

We were able to arrange a test staging out of MarineMax in St. Pete Beach, Florida. MarineMax is Aquila’s exclusive distributor in the US. The Aquila brand is owned by the Sino Eagle Group, a high-tech Chinese builder that extensively uses vacuum-infusion technology to build the boats. J&J Design Group provided a complete design package for the Aquila 36 Sport.

Aquila is largely the brainchild of Lex Raas, Alain’s father and president of Aquila at MarineMax. Lex is South African, and his career journey has taken him from working for Beneteau (the world’s largest boatbuilder) to the Moorings (the world’s largest vacation charter operation) to MarineMax (the world’s largest boat dealer). While a big believer in power catamarans for their roominess and comfort, Lex didn’t like that most were converted sailing vessels. The unveiling of the Aquila 36 Sport power catamaran in 2017, the company’s first outboard-powered model, ushered in a new era of high performance. Because these boats would be used on bareboat charters driven by skippers of varying degrees of expertise, they are purposely designed to be easy to pilot.

One Cool Cat

Our first sea trial began aboard the nonfoiled Aquila, joined by Alain Raas and Jacob Coyle, a MarineMax sales associate. When we headed out into the Gulf of Mexico through the Pass-a-Grille entrance, the wind was blowing 17 mph and gusting to 23 mph from the northwest, creating steep 4-foot waves. In other words, it was a glorious cat day.

Our nonfoiled test boat was powered by a pair of Mercury Verado 400 outboards derived from the Mercury Racing division. This engine does some serious overachieving given its smallish 2.6L inline-six-cylinder block, thanks to twin-scroll superchargers, which lend it substantial punch when a driver needs a blast of power. Ultra-rapid acceleration is less important for catamarans, which usually do best in rough water when kept at a steady speed that is faster than you would think.

Read Next: Aquila 36 Test

The big difference between most power cats and the 36-foot Aquila 36 Sport is the Aquila’s incredible 14-foot-7-inch beam, which creates a living room’s worth of space in the cockpit/salon for up to 26 passengers and is mostly enclosed by an optional hardtop. In addition to helping its optional Joystick Docking for Outboards system work more efficiently, this wide footprint creates an ultra-stable platform that will be reassuring to those without sea legs (or stomachs). It’s so stable, according to Alain, no customers have ever asked Aquila to install a Seakeeper gyrostabilizer.

Settling into a cruise speed of 33 mph felt like the cat’s happiest velocity for that sea state. The narrow profile of the twin hulls cleaved the water without the pounding that characterizes most monohulls when running into steep waves. We used a little bit of engine trim to bring the bow of the hulls out of the water to reduce drag and prevent bow steering, and the boat offered a smooth ride, even when we turned the beam to the waves. Narrower cats of similar lengths can snap-roll alarmingly in large beam seas, but the Aquila remained surprisingly level.

Heading into Bunces Pass is tricky because of shoaling on each side, but once through, it put us squarely into the Tampa Bay area’s recreational boating epicenter. With Egmont Key State Park and Fort De Soto Park to starboard and Shell Key Preserve to port, we were surrounded by great beaches that are perfect to nose up to. The Aquila 36 Sport Hydro Glide showed off its ability to float in just 2 feet of water with the engines trimmed up as we beached it. We beached the foil boat too. Even though the bottom of the foil is about a foot lower than the hulls, its extruded aluminum construction is stout enough to withstand being gently beached.

Time to Fly

Switching boats, we were curious to feel the difference the foil makes. The experience was subtle. The Hydro Glide foil is positioned just forward of the boat’s longitudinal center of gravity and set at zero degrees of attack, allowing the driver to use engine trim to increase the angle for optimal lift. On this boat, little trim is needed because the optimal angle of attack of the hydrofoil is only about 1.5 degrees, according to Lex. In our case, because the fuel tanks were almost full, we just trimmed the engines to their neutral position and let the weight of the fuel give the Aquila 36 Sport Hydro Glide its proper bow-up angle.

Because the Hydro Glide Foil System lifted the hull only about 6 inches, there was a general feeling of riding higher in the water, but the most tangible evidence was how the steering felt lighter and more responsive—an indication that the foil is running at its proper angle of attack. The wake behind us flattened out significantly, unlike the tall rooster tail and wake that shot aft from the nonfoiled boat. Offshore, it handled the steep chop well and felt best at a cruise speed of 38 mph. There was never a moment when it lost its lift from the foil.

Another difference lay in the cornering characteristics. Without the foil, the 36 Sport has a slight lean to the outside, which some find off-putting. With the Hydro Glide foil, the cat leaned slightly inward and felt nimbler as it carved hard turns. A driver can overcook it during extremely hard turns—the hulls can dig in and turn more sharply than expected—so whipping it into a corner like it’s a jet boat isn’t advised.

Foils that raise a boat’s hull entirely out of the water can plummet should the boat lose lift. But the dihedral V-shape of the Aquila’s foil allows it to descend a little at a time when exposed above the water. This results in gentle corrections in heave, or a boat’s up-and-down motion.

The Numbers Don’t Lie

The Aquila 36 Sport Hydro Glide reached plane in 6.4 seconds, which was 1.4 seconds faster than the nonfoiled boat. Its zero to 30 mph time was 2.4 seconds quicker, taking 12.4 seconds. While those might sound like modest gains, remember this test boat had twin 300 Mercury Verado engines—200 fewer horses than the nonfoiled boat. Of course, these 300s are the new-generation Mercury V-8 engines, featuring 4.6L in a naturally aspirated design instead of the 400′s 2.6L twin-supercharged powerplant. Having two more cylinders and 2 liters of increased displacement negates the need for supercharging because big blocks inherently have more low-end torque.

Most impressive was the lack of penalty for going fast on the 36 Sport Hydro Glide. Even at its top speed of 44.7 mph, it was still getting nearly 1 mpg, and the effect on its range was dramatic. At that speed with a full 356-gallon tank, we could theoretically travel the 322 miles from St. Pete Beach to Havana, though exceeding our 10 percent reserve. The nonfoiled Aquila 36 Sport, traveling at its top speed of 46.1 mph, would fall well short of reaching Key West (231 miles away) with a full tank. At its best cruise speed of 30.6 mph, the hydrofoil-equipped Aquila can go 381.5 miles, compared to the nonfoiled version’s 303.9-mile range, when traveling at 29.4 mph, factoring in a 10 percent reserve.

At first blush, opting for the Hydro Glide Foil System might cause sticker shock with its $32,452 price tag, which equates to running through about 13,000 gallons of fuel at $2.50 per gallon to recoup the investment. But if you factor in the difference in buying a pair of 300s versus 400s, the price is much closer, and you get a better-handling boat with more capability because of its increased range. Aquila 36 Sport owners will be happy to discover the Hydro Glide Foil System can be retroactively fitted at an estimated additional labor cost of $10,000. Twin 300s are the max power with the foil because higher speeds cause cavitation, which then adds drag. But the improvements in ride, acceleration and range make this the biggest no-brainer on the options list.

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Foiling technology: everything you need to know about hydrofoils

Fitting foils to powerboats is all the rage, but how do they work and why is foiling back in fashion?

What is foiling?

Foiling refers to the use of hydrofoils attached to the hull of fast boats, which provides additional lift at planing speeds – often enough to lift the hull completely clear of the water.

What is the benefit of this?

Efficiency. The enemy of fast boats is the amount of effort required to push them through the water. Planing boats go some way to addressing this by rising up over their own bow wave and skimming across the surface, but the stern sections are still immersed, creating significant hydrodynamic drag. It follows that if you can lift the boat completely clear of the water, hydrodynamic drag is only acting on the foils themselves and the sterngear that propels and steers it.

Any advantages beyond efficiency?

Lifting the boat clear of the surface can reduce the disturbance of waves, smoothing the ride, but only up to a point. It’s not just about lift though – active foils can also be used to improve stability or handling and in some circumstances, can improve efficiency even without lifting the boat.

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How do foils work.

Foils work in a similar way to aircraft wings. In simple terms, as they move through the water they deflect the flow, which exerts a force on the foil. If that force is upward, the faster they move, the greater the lift.

So why are they so much smaller than aircraft wings?

Because water is much denser than air – almost 800 times, in fact. The foils have far more to push against than aircraft wings, so don’t require the same surface area.

Is this new technology?

Far from it. Foiling technology can be traced back to 1898 when Italian inventor Enrico Forlanini began work on a ‘ladder’ foil system, obtaining patents in both the UK and the USA. He had a prototype operating on Lake Maggiore soon after. British boat designer John Thornycroft followed up with a series of scale models featuring stepped hulls and a single foil, and by 1909 had a full-scale 22ft prototype running. During WWII, the German military developed a 17-tonne foiling mine layer that was tested in the Baltic at speeds of up to 47 knots. By the early 1950s, the first commercial hydrofoil ferry was running between Italy and Switzerland and a decade later, a private hydrofoil yacht featured in the Bond movie Thunderball.

Why did they never catch on in production boating?

Traditionally, high-speed hydrofoils used large V-shaped foils that jutted out beyond the boat’s beam. This made berthing tricky and increased the draught. They were also costly to construct, vulnerable to damage and difficult to power, as the propellers of conventional shaftdrives would be clear of the water once foiling. Lastly, although hydrofoils were often more efficient than monohulls, high-speed cats could usually match the efficiency without the drawbacks.

Why are they back in the news?

Foiling technology came back into public focus when the 2013 America’s Cup contenders started to use foil-shaped daggerboards to hit speeds of more than 40 knots. Ben Ainslie’s spectacular last-gasp victory for the Oracle USA team and his subsequent BAR Land Rover Cup Challenger brought foiling to a global audience. More recently, we’ve seen the emergence of several foiling motor boats, including the SEAir RIB and the Sunreef Open 40 Power. More exciting still is the news that Princess will use an advanced Active Foil System on its new R Class superboat .

What has changed?

Technology has overcome many of the shortfalls of older systems. Simon Schofield, chief technology officer at BAR Technologies, told MBY the real game changer has been the adoption of ‘Dalí’ foils. Instead of two fixed V-shape foils, Dalí foils use four independent L-shaped blades that stick out of the hull at an angle before curving up like Salvador Dalí’s famous moustache. They are far more efficient and can be retracted, solving the berthing and draught issues. In addition, computer-controlled active systems allow the foils to be adjusted to suit speed and sea conditions. This doesn’t just improve efficiency, it can enhance the ride and handling too. When cornering, for example, a traditional hydrofoil boat doesn’t lean into the turn, making it uncomfortable for passengers. An active system can adjust each foil to induce the correct degree of lean. Modern materials also reduce drag and cavitation.

How about propulsion?

The Enata Foiler uses twin BMW diesel 320hp engines, but instead of being connected to the propellers with hefty drag-inducing shafts and gearboxes, these generate electric power which can be sent down a thin flexible cable to slender electric motors mounted on the retractable rear foils.

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ETF26: The trailer foiler bringing the foiling experience to the masses

• Matthew Sheahan
• December 17, 2019

The ETF26 is a super-light foiling catamaran designed to be sailed by ‘average’ sailors as well as professionals

Seven knots of true wind and a few quick pumps on the mainsheet was all it took to have the 8m cat rise up onto her foils and slip downwind at 16 knots. I’ve been faster, but in such calm conditions and flat water, to hiss past dozens of conventional keelboats sitting bolt upright as they ghosted along was a surreal experience.

I struggled to believe my GPS plot but there it was, a steady 16 knots with several peaks of 17. And on Lake Geneva, no tide could artificially inflate the figures.

With the gennaker furled as we rounded an imaginary bottom mark, the S-shaped daggerboard pushed all the way down to set the under water part of the foil in the L-configuration, we settled into the upwind ‘leg’ in displacement mode. Even here we were slicing along at just over 10 knots. It was clear this is an exceptionally slippery boat.

ETF26 flies close to the water surface for better control. Photo: Martina Orsini

That’s just what you might expect given that we were sailing the ETF26 on a lake that is famous for its lightweight flyers on the eve of the world’s biggest lake race, the annual Mirabaud Bol d’Or.

But while the ETF26 demonstrated her impressive and nimble performance in the light, my hosts were not to know the level at which they’d be tested 24 hours later when a vicious 60-knot storm, complete with torrential rain, hail and lightning, swept the lake.

Despite the horrendous conditions, they and two of their sisterships survived the pasting. Many bigger boats didn’t. Another impressive performance by what is essentially an overgrown, upmarket beach cat.

Article continues below…

Monofoil: The pocket rocket that can foil in just 8 knots of breeze

The spectacle of a flying catamaran, be it an Olympic Nacra 17, a GC32, the recent America’s Cup 50-footers, or…

Eagle Class 53: The foiling cruiser inspired by the America’s Cup

Not everything that flies is destined to scorch around an America’s Cup course. The future for sailing hydrofoils is surely…

Conceived by offshore legend Jean-Pierre Dick, designed by Guillaume Verdier and originally launched in 2016 as the ‘Easy To Fly 26’, the ETF26 has been quietly building support in an ever-expanding market of high octane hydrofoiling cats.

Now, with a fleet of 12 boats built and a European racing circuit that drew seven teams across three European venues last year for the second consecutive season, the newly rebranded class is gathering pace.

But this is more than just another foiling flying machine designed to fill a gap in the market. This is a high performance cat aimed as much at normal sailors new to multihulls as it is for experienced foiling fanatics or fearless youths. The owner of Cool Runnings is a prime example of just this.

The carbon hulls are mainly solid laminate in order to achieve robust structures that can be easily repaired. Photo: Gilles Morelle

“I have very little depth to my sailing experience,” said Thorkild Juncker. “After sailing as a kid in Denmark I gave up for 30 years and came back to it with an X35 and then a Dragon, as I wanted to learn how to helm.

“From there, I had an Open 7.5 sportsboat, but having seen the America’s Cup boats in 2014 I knew I wanted to have a go at foiling. So I set myself a goal, to learn how to race a foiling boat by the time I was 60. I’m 63 now and absolutely loving it. The big thing is getting used to the speed, but when you do it’s superb, there’s so much going on when you start getting into the high 20 and low 30 knots.”

Class founder Jean-Pierre Dick had also been drawn to foiling through watching the AC70s in the San Francisco America’s Cup. “As soon as I saw them race I thought ‘this has to be the future’. But my idea was to create a boat that would appeal to the large numbers of sailors who, like me, had been racing sportsboats like Melges 24s,” he said.

The sails are by North Sails and include a deck sweeper for the mainsail that improves the sail’s aerodynamics by creating an effective end plate, said to give more stability in flight. Photo: Martina Orsini

“But there was nothing really in this size. There was the Flying Phantom, which was too small, and the GC32, which was too big, heavy and expensive. So we started the project with Guillaume Verdier. Today we have a strict one-design class that suits a crew of three or four within the 260kg max crew weight limit. Light weight is one of the keys to this boat, the ability to fly easily means that we were able to create good handling characteristics and make her a safe boat to foil.”

Of the two key features that help this, a simple deck layout and foil controls are one, the ability for the boat to ride close to the water, at around 50cm, is another. “Our boards are much shorter when you compare them to, say, a GC32,” continued Dick.

“Flying lower is safer if you do crash. Also, when we sail downwind we raise the S-boards slightly, which makes for more of a V configuration under the water. This helps to achieve a degree of self-levelling and makes the ride more stable,” he said. Dick is understandably proud of the fact that so far no one has pitch-poled their boat and, while there have been a handful of capsizes, no one has yet broken anything as a result.

Daggerboards are manually raised/lowered and trimmed using the orange control lines. The S-shape allows the daggerboards to switch from upwind to downwind mode. Photo: Matt Sheahan

But while the cat is easy to manage, all are clear that foiling requires a number of different techniques. Cool Runnings ’s principal helmsman and professional sailor Jochen Visser admits to a background entirely in monohull keelboats and points to some of the key differences that he and his team of cat novices have had to learn.

“Getting used to the speed is one key factor. The laylines come up very quickly indeed, so quickly that you have to have your plan sorted before you start racing,” he said. “There’s no time to work things out once you’re under way, like you might do on the Dragon on the downwind leg.”

Boathandling is another new skill set. “We can be travelling at 35-36 knots in flat water but drop the speed down to around 25-28 in waves in order to make the boat more controllable,”  he continued.

“Another of the key handling details is learning not to ease the mainsheet for the bear-away at the top mark. These boats accelerate so fast that you don’t need to and don’t want to either as you simply twist off the mainsail and cause all kinds of trim issues. It feels counterintuitive at first, but it’s details like these that you need to learn and it’s exciting.”

For the construction of the ETF26, Dick set up an assembly facility called Absolute Dreamer. “The hulls are built by Multiplast, the mast and boom by Axxon Composites and the rudders and foils by Avel Robotics,” he said. “The whole boat is designed to be rigged or de-rigged and packed on a trailer in around two hours. You don’t need a crane to step the mast and the cat can be launched off the trailer, so it’s very versatile.”

Cool Runnings ’s owner Thorkild Juncker trails his boat and their support RIB on the same trailer around to the various European regattas behind a normal car or van. Photo: Matt Sheahan

All of which makes for a boat that is easily manageable by a team of three for weekend sailing. Add to this the appeal for those looking to step from the real world of enthusiastic amateur sailing into the foiling world and Thorkild Juncker’s enthusiasm sums up the appeal. “When I saw foiling for real I just thought, sailing hasn’t changed in 2,000 years and now this – I have to be a part of it!”

Specification

LOA: 8.10m (26ft 7in) Beam: 4.30m (14ft 1in) Mast height: 13.70m (44ft 11in) Draught: 1.20m (3ft 11in) Weight: 350kg (772lb) Main Sail 3Di: 29.50m² (318ft 2 ) Self-tailing jib 3Di: 11.00m² (118ft 2 ) Code 0: 26.50m² (285ft 2 ) Gennaker: 49.50m² (533ft 2 )

First published in the December 2019 edition of Yachting World.

Professional BoatBuilder Magazine

The people’s foiler: a design brief on the ufo foiling catamaran.

By Dave Clark , Mar 14, 2017

The father-and-son design team of Steve and Dave Clark develops the UFO, a stable, affordable, production-built foiling beach catamaran.

To design an affordable hydrofoil, Steve and Dave Clark realized they couldn’t just strip down an existing high-performance model. Their foiler also needed to be efficiently produced, durable, easy to launch, and forgiving to amateur sailors.

It’s June 2015. I’m chatting on the phone with my tugboat designer friend Bill: “Dad and I have been kicking around the idea of using a set of decent hydrofoils to get a simple, cheap boat to really perform without any of the pain, hassle, and expense we’ve all become accustomed to as the price of admission for foiling under sail. I can’t get it out of my head. Dad’s certain it’s possible to build, and I’m convinced people would like it.” I go on for a bit, describing the basic concept work we’ve done to date. Bill cuts in, his voice suddenly hard and assertive.

“You think so?”

“Do it. Test it under cover of darkness. Tell nobody. Don’t sit on it. You’ll never forgive yourselves if 10 years down the line you see somebody else make it something more than a drawing.” And we did it.

The job could have been simple: create a detuned civilian version of a proven high-performance foiling craft. This design project would normally start with identifying and removing every bit of costly exotic material and excess labor from the existing model we were detuning. But we were certain that with small foilers there’d be conversion issues beyond expense, including storage, transportation, and difficulty of use.

The competitive boats we were looking to emulate were designed to achieve performance goals but with little regard for convenience and userfriendliness. Informing those designs was thinking that went something like this: When you’re aiming to be the world’s fastest Moth, what does it matter that it takes two hours to put together and you need to walk shoulder-deep into the water towing a capsized boat with nonretractable foils to launch? What does it matter that the boat has a permanently unstable foot-wide waterplane? When you’re trying to build the world’s fastest A-class, what does it matter that the boat won’t collapse and takes up more space than a J/24 at the club? What does it matter that it’s nearly as expensive as a Porsche to own and just as costly to maintain? When you’re trying for absolute outright speed, what does it matter if it crashes, bites you, and requires constant tuning changes? Surely all those things are user-error. Just get that gash in your face stitched up, grow five more testicles, and realize the speed you’re going for. C’mon!

We recognized that to really distill the fun of foiling—one of the most profound pleasures in sailing—we’d need to take the self-harm out of it. We’d have to do more than simply reduce costs on an existing foiler precisely because existing foilers were developed by today’s foiling sailors, who are exceptional. Ours needed to bring a certain degree of civility and simplicity to the foiling experience.

The final brief was:

• A compact sailing hydrofoil that delivers credible performance at all points of sail in a broad wind range.
• Dimensions of less than 12′ long and 6′ wide (3.7m x 1.8m) and a vessel weight of 110 lbs (50 kg).
• Able to be rigged, launched, and retrieved upright, and sailed and maneuvered in shallow water.
• Forgiving—That is, not dependent on advanced sailing skills.
• Inexpensive and durable enough to be accessible to a wide variety of users.
• Easy to store and transport.
• Carrying profit margin sufficient for the builder to remain in business with active promotion.

We drew on a few main ingredients. First were the millions of hours the International Moth class has put into iteratively testing and perfecting centerline T-foils and their control systems. Second was a heavy dose of foil, sail, and aero-package studies my father, Steve Clark, had recently commissioned from Paul Bogataj for the 2015 Little America’s Cup campaign, a program that included a conversion of the C-class cat to full foiling, a sealed trampoline, end-plating, and canting the wing—all sorts of fun stuff. (For more on C-class development, see “Flight Plans,” by Steve Killing, in Professional BoatBuilder No. 151.) As is often the case, there’s no boat better than the one you’re going to build next. The nascent UFO (Unidentified Foiling Object) had the good fortune to be the next boat after the C-class campaign. Finally, there’s the normal grab bag of development knowledge picked up over the years in the A-class, the IC (international canoe), various skiffs, and Dad’s career manufacturing 3,000 boats a year at Vanguard. As always, the path you follow is a function of who you are and what you know.

My father has had a fondness for solid-decked catamarans since he received an Alcort Catfish for Christmas 52 years ago. It’s an underexploited hullform that keeps the part count exceptionally low and allows for a high degree of performance and stability. It fit the bill in low cost, high stability, and ability to attain the speed necessary for takeoff.

Our first critical task was to keep the surface area low enough to yield a strong, light, easily built shape. Getting it right took several iterations at the modeling phase as well as careful laminate design and testing. We settled on a vinylester-infused laminate of Soric foam core skinned with E-glass cloth and minimal strategic reinforcement with unidirectional carbon. This kept internal framing to a bare minimum, saving man-hours and keeping the build uniform. A lot of our success in this endeavor is down to exploiting the physicals of high-quality vinylester and the reduced panel-stiffness require­ments for something that is mostly airborne while under way, where the fluid is roughly 800 times less dense than water.

Profile and plan views of the UFO (Unidentified Foiling Object).

UFO particulars:

• LOA 10’6″ (3.2m)
• Beam 5’7″ (1.7m)
• Light ship 110 lbs (49.9 kg)
• Sail area 84 sq ft (7.8m2)

The second, most obvious judgment call was to make the boat from two parts, bonded with a single straight lip joint for the whole perimeter. Hull + deck + external flange joint + Plexus = done and dusted. Conventional rolled-lip joints were developed for an era when weaker glue required higher glue area, and coffee-can joints that offer a “seamless” look are an invitation to countless hours of hand-finishing everything. More often than not, they violate the promise of gelcoat by requiring the joint to be faired and repainted. When building small production boats, if you aren’t pulling polished, gelcoated, essentially done parts out of the mold, you won’t be cost-effective.

The Clarks chose a solid-deck catamaran hullform for its low cost, high stability, and ability to attain foiling speed. At 70 lbs (31.5 kg), it’s also easy to handle and has dimensions and a bottom that lend themselves to cartop transport.

No matter how small you make the surface area, the hull will be the largest, most expensive part of a dinghy. With that in mind, you often need to put function first to control costs. The light, cheap, durable, and reliable solution for a hull-to-deck joint is a single half-inch (12.7mm) flange. It looks a bit funny in places, but it’s a small price to pay for a lightweight bond that eliminates the need for any secondary work.

The Clarks simplified production by designing the UFO’s hull and deck parts to be joined with a single straight lip. The vinylester-infused laminate of Soric foam core and E-glass includes minimal carbon reinforcement of the beams for stiffness.

Another detail on the UFO is the absence of tight areas where it would be difficult to reach into when building the boat. Even the bows are built with a wide stem radius, to make stacking the laminate easy and reliable.

I’m a firm believer in attacking a problem from both ends. Though we did an FEA (finite elements analysis) on all parts of the boat, we also performed what I call an additive guess-and-check FEA as well. This consists of creating a hull as intentionally underbuilt as possible, putting a ton of hours on it, patching it where it breaks, and counting the patches. It’s an empirical way of finding the hot spots in the build and serves as an excellent complement to the FEA for designing the final laminate.

Locating the mainfoil trunk just forward of the mast provides a couple of immediate benefits. First, the foil may be withdrawn between the hulls and clear of the rig for launching and landing, something that’s not possible on most foilers. On most, the lifting surfaces of their choked-up foils are sticking out the sides, jammed against the bottom of the hull, and in the way of the dolly. Not so for the UFO, whose foils pull up well clear of the waterline.

Because the hulls provide good lateral resistance, they enable a “beach cat mode” where the boat will operate normally, tacking, jibing, and achieving all points of sail with the mainfoil up and the rudder partially down. This idea dates back to a far earlier conceptual cousin of the boat that my dad doodled back in 2006. Second, it makes sealing the sail to the deck even easier.

Sealed or “endplated” sails gain apparent aspect ratio and feature a lowered center of effort and far less tip vortex drag at the bottom of the sail, thus driving up the performance a notch. It’s seen a spike in popularity lately, and part of the game is getting the “turntable” that the sail sweeps across as clear as possible. Moving the daggerboard out of there helped with that. Placing the board forward of the mast may seem abnormal to some, but one does not make a foiling omelet without breaking a few conceptual eggs. In practice, this board location has been proven for decades on all boats with canting keels and requires just basic math to get the balance right.

More often than not, the variable cost center of a dinghy is aloft. It’s quite easy to lose all the budget victories you’ve made in hull design and process control by choosing the wrong spars and cloth. The easy solution would be to go down the Laser route and put a small full sail on cheap aluminum tubes, but that will not perform well enough for a foiler, or meet weight targets. While a fully battened Mylar sail can be made cost-effectively enough, a freestanding carbon spar would murder the budget. We found that a long composite sailboard spar, built in volumes that dwarf all other spars, is priced at an exceedingly seductive level but, on its own, lacks the stiffness to do the job. In addition, foilers work best with high leech tension, so much so that the booms and tension vangs on foiling Moths are historically plagued by breakage.

Without question we had a spar problem that required a creative solution. I found the answer quite by accident while looking at the 1930s Her­reshoff Amphi-Craft on display at the T.F. Green Airport (Warwick, Rhode Island). The boat featured a primitive straight-sparred wishbone boom system, held at its forward tips by wire diamonds and short wire tethers running straight aft to the mast.

Dave Clark was inspired to design the jumper-strut wishbone-boom rig after he spotted a 1930s Herreshoff Amphi-Craft like this one on display at his local airport. The adjustable rig allows for changes in mast stiffness and leech tension to be made by the helmsman while under way.

For a moment I mistook the tethers for spreaders, and realized that diamonds, plus compression struts (spreaders), plus wishbooms married to the tips of those spreaders would allow a cascade of benefits. You could swap out the stiffness needs of the spar with tension strength in Dyneema jumper stays, and replace the tension needs of the vang with compression strength in the booms. This would allow these forces to efficiently cancel one another out, resulting in a conventional stiff spar with a tight leech, while still being based on that inexpensive, flexible sailboard spar. This is the core concept of our original “jumper strut” arrangement, which, finding no prior art, we’ve provisionally patented. We find that it supports and works the sail in all the ways it should and has the added benefit of enabling a lighter-weight sailor to “turn off” the rig stiffness by releasing tension on the jumpers, effectively depowering the boat in windier conditions. This yields a surprisingly wide tuning range for a freestanding rig.

The other risk when designing a sailboat for yourself is the budget-crippling shopping spree at the chandlery. While riddling the boat with on-the-fly tuning systems and little bungee-driven take-ups is a complete blast, and leaves the boat completely caked in bling, it also costs more than any reasonable customer can afford. For beginners, this often booby-traps the boat, physically ensnaring them in a nest of systems they don’t want or understand. So we kept the deck layout pointedly sparse. There is a Cunningham and a mainsheet. Oh, and a tiller. Go sailing.

We did our best to keep the hydrofoil system conventional, because we had no interest in subjecting our customers to an ego-driven science experiment. The UFO runs on a Moth-type system. The daggerboard (mainfoil) and the rudder are fitted with horizontal wings on their bottom ends. The mainfoil has a flap on its trailing edge actuated by a surface-sensing wand at the bow. When the hull is low to the water, the wand drags aft, and a series of bell cranks and connecting rods attached to it push the flap down, generating increased lift. When the boat is flying on the foils and the wand is not touching the water, the opposite conditions apply, and the system corrects downward. As a secondary consequence, this controls the pitch of the whole boat.

These components combine to determine the flight path of the boat at a set altitude, dictated by the length of the wand. This basic system was originally patented in May 24, 1955, and has been applied to a range of foilers since then. (See Jim Brown’s feature about Sam Bradfield, “Takeoff Window,” PBB No. 108.) Since 2002, this configuration has been vigorously refined by competitors in the ever-growing International Moth class, which has leveraged the technology to yield unquestionably the world’s fastest single­hander.

With foils pulled up between the hulls, the UFO can be easily launched via a beach-style dolly.

We commissioned Nat Shaver, a friend who currently designs foils for the French America’s Cup team, to design the foil shapes. The result is a very gentle, high-lift package. Our objectives of modest and forgiving foiling performance aligned nicely with our cost objectives, as the less you prioritize absolute top-end speed, the easier the foils become to manufacture. Extruded aluminum vertical struts coupled with vinylester, glass, and carbon compression-molded lifting foils achieve 80% of the Moth foil package’s performance at a cost that’s lower by two orders of magnitude. Again, picking out our own design ground yielded benefits over merely value-engineering what already exists.

In Perspective

What we get in the end is a boat that fulfills the brief and has made sailing fun again on a personal level. Having grown up with some of the fanciest sailing toys that money and custom fabrication could produce, I can be as jaded as anyone about going out for a spin. Not with the UFO. At some point last summer I, having felt a puff, was rushing off to rig up for a test flight. As I hustled to get my gear, Dad pointed out, “I haven’t seen you this excited to go sailing in a long time.”

The UFO was designed to bring foiling to the masses. It has also made sailing fun again for Dave Clark.

He was right. There’s something truly special about foiling. You build speed, suddenly start rising up as the boat goes dead quiet and gains another burst of speed as all your hull drag and most of your strut drag vanishes. You are the wind. Being able to do that without wasting time rigging anything fussy or going through some sort of convoluted launching process, or fighting breakages and impossible maintenance and finish standards, has been completely liberating.

I’m glad we did this, and it’s a 
complete pleasure sharing it with everyone.

About the Author: Dave Clark began his apprenticeship under Steve Clark (Vanguard Sailboats 1985–2007) in 2004. He has been making an ass of himself and wasting expensive materials ever since.

Editor’s Note; The above article was originally published in Professional BoatBuilder No. 166.

For more about the UFO:

Video: Dave and Steve Clark’s UFO Foiling Catamaran

Great , ok where can i buy one and get it delivered to south of france ?

Hi there, Their website with more information on how to buy is at http://www.fulcrumspeedworks.com/UFO/ . Good luck!

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The Society of Naval Architects and Marine Engineers (SNAME) Technical and Research Program, in cooperation with the Hampton Roads, Virginia Section of SNAME, will host the Sixth Annual Powerboat Symposium… Read more »

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ProBoat.com Archives

How SailGP’s foiling F50 catamarans sail so much faster than the wind

Arguably the most technologically advanced sailboats on the planet right now, the one-design SailGP F50 foiling catamarans are capable of breathtaking speeds – at times, reaching four times the velocity of the wind that drives them. But how do they do it?

Beating the balloon

Bending the laws of physics

Faster and faster

Beneath The Surface

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Meet the denmark sailgp team, find all the latest news, go beneath the surface of sailgp, sailing terms, go beneath the surface.

How the world’s fastest sail racing boats fly above the water

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How Do Hydrofoil Catamarans Work? (The Science Behind It Explained)

Have you ever wondered what it would be like to fly on the water? Hydrofoil catamarans are designed to do just that, and many people are amazed by the experience of gliding across the water at speeds that are unheard of with traditional boats.

But what are hydrofoil catamarans, and how do they work? In this article, well explain the science behind these revolutionary boats and explore the advantages, design considerations, and safety precautions that come with them.

Well also look at some examples of hydrofoil catamarans to show you just how powerful and advanced they are.

So, if youve ever wanted to know how these boats work and what sets them apart, read on!

Table of Contents

Short Answer

Hydrofoil catamarans work by using foil-shaped wings that protrude from the bottom of the boat, below the water line.

The foils are designed to lift the vessel out of the water, reducing the surface area touching the water, and therefore reducing drag.

As the boat moves forward, the airflow on the foils generate lift, causing the boat to rise out of the water and glide along the surface.

The foils act as an air cushion, allowing the boat to travel at higher speeds than a regular catamaran.

What are Hydrofoil Catamarans?

Hydrofoil catamarans are a type of boat that use hydrofoils to lift the hull above the water.

This reduces drag, allowing for faster and smoother sailing than traditional boats.

Hydrofoils are wings that protrude from the hull of the boat and are designed to lift the boat out of the water.

This reduces the amount of water resistance and allows the boat to travel faster.

The hydrofoils are adjustable, allowing the boat to be tuned to the desired speed.

Hydrofoil catamarans offer an efficient and fast way to travel on the water, making them a popular choice for recreational and competitive sailing.

The hydrofoils work by creating lift as the boat moves through the water.

As the boat moves, the water flow pushes against the hydrofoils and creates a pressure differential.

This pressure differential creates lift, which lifts the boat out of the water and reduces drag.

The hydrofoils also reduce the amount of wave resistance, allowing the boat to glide through the water.

The hydrofoils can be adjusted to match the speed of the vessel, allowing the boat to be optimized for maximum performance.

The angle of attack of the hydrofoils is also adjustable, allowing the boat to be tuned to the desired speed.

The fins are designed to keep the boat stable and can be adjusted to match the speed of the vessel.

In conclusion, hydrofoil catamarans are a type of boat that uses hydrofoils to lift the hull above the water.

How Do Hydrofoils Work?

Hydrofoils are a type of boat that uses a set of wings or fins to lift the hull above the water.

The hydrofoils are attached to the hull and use the water pressure to propel the boat forward.

The wings of the hydrofoils are designed to reduce the amount of wave resistance, allowing the boat to glide through the water with greater efficiency.

The wings are usually made of lightweight materials such as carbon fiber or aluminum and are designed to produce lift when the boat is moving at a certain speed.

The wings can be adjusted to different angles, which can increase or decrease the lift.

When the boat is moving, the hydrofoils create a low-pressure zone underneath the boat.

This low-pressure zone reduces the amount of drag and improves the efficiency of the boat, allowing it to move faster and more smoothly.

The hydrofoils also help to reduce the amount of wave resistance, allowing the boat to glide through the water with less effort.

They are suitable for all kinds of sailing, from racing to cruising.

Hydrofoils can be adjusted to match the speed of the vessel, making them an excellent choice for those who want to sail faster.

Hydrofoils are also a great choice for those who want to reduce their environmental impact.

Hydrofoils reduce drag, which means that they require less fuel to move the boat, resulting in lower emissions.

Hydrofoils are a great way to reduce the environmental impact of sailing while simultaneously enjoying a faster and smoother ride.

Advantages of Hydrofoil Catamarans

Hydrofoil catamarans offer a unique and efficient way to travel on the water.

The hydrofoil design reduces drag, allowing the boat to glide through the water with greater speed and stability than traditional boats.

The hydrofoils are attached to the hull and use the water pressure to propel the boat forward, creating less wave resistance than a traditional boat.

This allows the boat to move faster and smoother, while using less fuel.

Additionally, the fins can be adjusted to match the speed of the vessel, making it easier to control.

The design of the hydrofoil catamaran also allows it to ride high above the water, reducing drag and contact with the water surface.

This allows for a smoother ride, allowing the boat to move faster with less fuel consumption, and less noise and vibration.

Additionally, the hull shape of the hydrofoil catamaran is designed to increase its stability and maneuverability, further reducing drag and allowing for a faster and smoother ride.

The combination of the reduced drag, increased stability, and smoother ride makes hydrofoil catamarans a popular choice for recreational and competitive sailing.

The ability to move quickly and efficiently makes them ideal for racing, and the increased stability and maneuverability makes them well-suited for recreational activities such as sightseeing or fishing.

Additionally, the reduced contact with the water surface can help to protect the hull from damage, making the boat more durable and longer-lasting.

Overall, hydrofoil catamarans offer an efficient and fast way to travel on the water, making them a popular choice for recreational and competitive sailing.

The combination of reduced drag, increased stability, and smoother ride makes them an ideal choice for anyone looking to get the most out of their time on the water.

Factors Affecting Hydrofoil Performance

The performance of a hydrofoil catamaran depends on a variety of factors, including the type of hydrofoil, the size and shape of the hull, and the speed and direction of the wind.

The hydrofoil itself is an important factor in determining the performance of a hydrofoil catamaran.

Different types of hydrofoils offer different levels of lift, drag, and stability, so its important to choose the right hydrofoil for the job.

The size and shape of the hull also affects the performance of the hydrofoil catamaran, as the hull is the part of the boat that provides the buoyancy and helps the boat to stay afloat.

The speed and direction of the wind also affects the performance of a hydrofoil catamaran, as a headwind or tailwind can cause the boat to be pushed or pulled in a certain direction.

Finally, the weight of the vessel also affects the performance of a hydrofoil catamaran, as a heavier boat will require more lift from the hydrofoil to remain afloat.

Design Considerations for Hydrofoil Catamarans

Hydrofoil catamarans are a special type of boat that use a unique design to offer efficient and fast travel on the water.

The key component of the design is the hydrofoil, which is a fin-like structure attached to the hull that uses the water pressure to push it forward.

This reduces drag and wave resistance, resulting in a smoother, faster sailing experience than traditional boats.

When designing a hydrofoil catamaran, there are a few important considerations that engineers must take into account.

The hydrofoils must be designed so that they can be adjusted to match the speed of the vessel, as well as provide stability and reduce wave resistance.

Additionally, they must be constructed from durable materials to ensure they can stand up to the elements and provide a reliable ride.

The shape of the hull also plays an important role in the performance of a hydrofoil catamaran.

A rounded hull is ideal for reducing drag, while a flat hull is better suited for stability.

As for the size of the hydrofoils, they should be big enough to lift the boat above the water, but not so large that they create too much drag.

Finally, the placement and size of the hydrofoils must be carefully calculated to ensure the boat can reach its maximum speed while remaining stable.

It is also important to consider the weight of the boat and its passengers when designing a hydrofoil catamaran, as this will affect the performance of the hydrofoils.

By taking all of these factors into consideration, engineers can design hydrofoil catamarans that are both fast and stable, providing an enjoyable and efficient ride.

Examples of Hydrofoil Catamarans

Hydrofoil catamarans come in a variety of shapes and sizes, making them suitable for a variety of applications.

Popular examples of hydrofoil catamarans include the America’s Cup boats, the A-class catamaran, as well as the Nacra and Tornado catamarans.

The America’s Cup boats are the fastest boats in the world and are designed to achieve speeds of up to 50 knots.

The A-class catamarans are lightweight and designed for racing, while the Nacra and Tornado catamarans are designed for recreational sailing.

Each of these boats use hydrofoils to reduce drag and improve performance.

In addition to recreational and competitive sailing, hydrofoil catamarans are also used for transportation.

The Sea Eagle is a high-speed ferry that uses hydrofoils to reduce drag and increase its top speed.

The ferry is capable of carrying up to 250 passengers and can reach speeds of up to 50 knots.

Other examples of hydrofoil catamarans include the hovercraft, which uses a combination of air and water pressure to lift the vessel above the water, and the AirFish, which uses a combination of air and water pressure to fly above the water.

Hydrofoil catamarans are an efficient and fast way to travel on the water, making them popular for recreational and competitive sailing, as well as for transportation applications.

The hydrofoils reduce drag and increase performance, allowing these boats to reach speeds of up to 50 knots.

The design of the hydrofoils can also be adjusted to match the speed of the vessel, allowing for a smoother and more efficient ride.

Safety Precautions for Hydrofoil Catamarans

Hydrofoil catamarans are a popular choice for recreational and competitive sailing due to their efficiency and speed.

However, these vessels require extra caution to ensure the safety of all passengers.

Before operating a hydrofoil catamaran, it is important to understand the safety precautions needed to ensure an enjoyable and safe experience.

First, always wear a personal floatation device (PFD) when operating a hydrofoil catamaran.

This will provide a layer of protection if you fall overboard.

Additionally, if the hull of the boat is lifted above the water, it is important to check the area for any debris or objects that may be submerged.

This could cause damage to the boat or injure passengers.

It is also important to check the weather conditions before going out on a hydrofoil catamaran.

Wind, waves, and storms can all be hazardous for these vessels.

They are not suitable for rough water and should be avoided during inclement weather.

Additionally, it is important to check the engine and fuel levels before embarking on any voyage.

Finally, it is important to understand the limitations of the hydrofoil catamaran.

These vessels are designed for speed and maneuverability, not stability.

They are not intended for large groups or for carrying heavy cargo.

The hydrofoil system can also be easily damaged by impacts with rocks and other objects so it is important to be aware of your surroundings and avoid any obstacles.

By taking the proper safety precautions, you can ensure an enjoyable and safe experience while operating a hydrofoil catamaran.

Always wear a PFD, check the weather conditions, and understand the limitations of the vessel before going out on the water.

With the proper preparation, you can enjoy the speed and efficiency of a hydrofoil catamaran for many years to come.

Final Thoughts

Hydrofoil catamarans are a unique type of boat that offers an efficient, fast, and smooth sailing experience.

The hydrofoils lift the hull out of the water, reducing drag and wave resistance, allowing the boat to glide through the water.

With the right design considerations and safety precautions, hydrofoil catamarans can be an enjoyable and safe way to travel on the water.

If youre looking for a fast and efficient way to get out on the water, hydrofoil catamarans may be the perfect option for you.

James Frami

At the age of 15, he and four other friends from his neighborhood constructed their first boat. He has been sailing for almost 30 years and has a wealth of knowledge that he wants to share with others.

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Hydrofoils: Boats That Fly

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Hydrofoils make everything from water skis to sailboats to giant ferries faster (much faster). But how the heck do they work?

Oracle Team USA's AC50 "flying" at nearly 50 mph. (Photo: Ricardo Pinto)

Ever wonder why a sleek, powerful recreational boat is not even as fast as a typical economy car? It has to do with friction. An economy car needs a little over 100 horsepower to speed by at 100 mph, but pushing a boat through the water that fast takes several hundred horsepower. The reason is that water is almost 800 times denser than air.

Imagine standing on your dock in a 10-knot wind — it's not hard to do. Now imagine being in a river trying to stand up to a 10-knot current. The water is so much denser that no matter how strong you are, you'd be swept away. A boat hull has to push through all that dense water while a car can slip through the air much easier.

Planing boats are able to go faster than displacement boats because they lift part of their hull out of the water as they race over their bow wave, but there's still a lot of friction from the water on the rest of the hull. If you could get the hull all the way out of the water, you'd eliminate that friction, and the boat could go faster with the same amount of power.

The Science

Most of us have a pretty good understanding of how an airplane flies. As air flows over and under the wings (also called airfoils), it creates lift. Once an airplane is going fast enough, the lift that the wings create allow it to rise above the earth.

If you were to mount a wing or two (called hydrofoils) under a boat, all that dense water can be put to good use by pushing the boat's hull out of the water. Then friction only acts on the small foils, not on the whole hull, which is why a 130-foot hydrofoiling sailboat can "fly" at over 50 knots. Powerboats have added friction from the propulsion system that has to remain in the water, but even then, large hydrofoiling ferries can exceed 45 knots.

Speed is not the only advantage that hydrofoils give boats. Because the hull is out of the water, all the energy from waves that would normally pound against the boat pass harmlessly underneath it, creating an eerily smooth ride. Even so, hydrofoiling is typically best in somewhat protected waters.

Don't look for hydrofoils on your next runabout anytime soon because they're much more difficult to engineer and typically triple the cost of a boat. The good news is that there are other ways to 'foil that are affordable — see "Experience Hydrofoiling For Yourself" at below.

Experience Hydrofoiling For Yourself

Hydrofoil kiteboards.

If you've even seen a kiteboard zooming in a strong breeze, you know they're plenty fast. Add a hydrofoil, and suddenly you add a new dimension. These boards take lots of skill and practice to master, but the ride is said to be much smoother and even faster than a conventional kiteboard. Cost starts at around $1,000.

Hydrofoil Waterskis

These single-ski hydrofoils are really a sit-on-ski, and once you've mastered the technique, the foils will lift you up and you'll be "flying." Unlike conventional skis, these aren't designed for speed, and 18 mph is where they typically "liftoff' and suggested top speed is about 25 mph. It's also important not to ski in shallow water due to the depth of the foils. Cost is typically $1,500 and up.

Hydrofoil Windsurfers

Not content to take a surfboard and add a sail, windsurfers developed foils that allow the board to "levitate." The biggest advantage is the smoothness of the ride — a real benefit because these rigs usually sail in very strong winds with plenty of chop. Cost is about $2,500 to get started.

Hydrofoiling Small Sailboats

You don't have to spend millions on a boat like the America's Cup racers if you want to hydrofoil. The Waszp costs about $10,000, though even for dinghy racers, there's a learning curve to get these boats on their foils, with speeds up to 27 mph.

Note that most companies suggest wearing a helmet when using foiling products because of the speeds achievable and the hard, sharp foils these devices have.

Foiling The Competition

America's Cup boats are often what people think of when they hear the word "hydrofoil." Hal Youngren, an aeronautical engineer and one of the designers for the 2013 and 2017 America's Cup racers, says the difference in speed that foils make is impressive. The fastest nonfoiling catamarans in previous races could barely reach 35 knots, while the 2017 foiling cats hit 50 knots. Youngren says that these 50-foot cats are able to lift their hulls completely out of the water using only about three-quarters of a square meter of foil area (about the size of a medium-sized TV). Below about 15 knots, he says, the boats sail much like a nonfoiling boat with hulls in the water, but once over that speed, the boats start to "fly" and their speed dramatically increases.

The America's Cup Class AC75 Boat Concept Revealed

An exciting new era in America's Cup racing was unveiled in November 2017 as the concept for the AC75, the class of boat to be sailed in the 36th America's Cup is released illustrating a bold and modern vision for high performance fully foiling monohull racing yachts.

The America's Cup AC75 Boat Concept Revealed

The Emirates Team New Zealand and Luna Rossa design teams spent the previous four months evaluating a wide range of monohull concepts. Their goals have been to design a class that will be challenging and demanding to sail, rewarding the top level of skill for the crews; this concept could become the future of racing and even cruising monohulls beyond the America's Cup.

The AC75 combines extremely high-performance sailing and great match racing with the safety of a boat that can right itself in the event of a capsize. The groundbreaking concept is achieved through the use of twin canting T-foils, ballasted to provide righting-moment when sailing, and roll stability at low speed.

An underlying principle has been to provide affordable and sustainable technology "trickle down" to other sailing classes and yachts. While recent America's Cup multihulls have benefitted from the power and control of rigid wing sails, there has been no transfer of this technology to the rigs of other sailing classes. In tandem with the innovations of the foiling system, Emirates Team New Zealand and Luna Rossa are investigating a number of possible innovations for the AC75's rig, with the requirement that the rig need not be craned in and out each day. This research work is ongoing as different concepts are evaluated, and details will be released with the AC75 Class Rule before March 31, 2018.

The America's Cup is a match race and creating a class that will provide challenging match racing has been the goal from the start. The AC75 will foil-tack and foil-gybe with only small maneuvering losses, and given the speed and the ease at which the boats can turn the classic pre-starts of the America's Cup are set to make an exciting comeback. Sail handling will also become important, with cross-overs to code zero sails in light wind conditions.

A huge number of ideas have been considered in the quest to define a class that will be extremely exciting to sail and provide great match racing, but the final decision was an easy one: the concept being announced was a clear winner, and both teams are eager to be introducing the AC75 for the 36th America's Cup in 2021. — AmericasCup.com

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Charles Fort

Contributing Editor, BoatUS Magazine

Charles Fort is BoatUS Magazine's West Coast Editor. He often writes local news items for BoatUS Magazine's Waypoints column and contributes to Reports, in-depth tech features in every issue written to help readers avoid accidental damage to their boats. He is a member of the National Association of Marine Surveyors, he's on ABYC tech committees, and has a 100-ton U.S. Coast Guard license. He lives in California.

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F1x A-class foiling catamaran

World champion, lighter = better, craftsmanship, meet the foiling f1x a-class catamaran.

This is the ultimate singlehanded foiling catamaran of the moment: ultramodern, incredibly fast, very agile, extremely strong and feather-light, in an aerodynamic and ergonomic design. The perfect total package, packed in 1 foiling catamaran. This is the world’s coolest boat for singlehanded races and the winner of several A-cat world championships and many other sailing races.

The 2020-F1x A-cat is exactly the same foiling catamaran that made Mischa Heemskerk Vice-World Champion at the Herveybay Worlds 2018 in Australia and World Champion at Weymouth 2019. All our foiling F1x A-class catamarans come straight, ready to race and ‘Mischa-tuned’ from our factory.

Unique design enables top performances

The F1x A-class foiling catamaran is the ultimate reflection of our current design language. The aerodynamic design accentuates the performance qualities of this super fast foiling racing boat. The sophisticated deck plan provides clear control and minimal air resistance.

Foils The rudders and daggerboard foils used on the F1x A-class foiling catamarans are produced with the highest quality carbon pre-preg fibers. The foils are cured in our own Autoclave . Our winning foil design was created in close cooperation with Glenn Ashby and the designers of AC Team New Zealand .

Construction The F1x A-cat is manufactured entirely according to the carbon pre-preg/ Nomex production method, and cured in our Autoclave. This technology is the same as used in the aerospace industry and within other foiling boats like for example, the America’s Cup.

Design The design of the F1x foiling A-class catamaran was completely conceived by the DNA design team and made at DNA’s own yard. In the DNA design team Pieterjan Dwarshuis, Mischa Heemskerk and the renowned Dutch industrial design engineer Rudo Enserink worked closely together to create the perfect foiling A-class catamaran.

We build your new foiling boat!

Technical details.

The F1x A-class foiling catamaran has a number of unique features that improve performance. For example:

• Semi ridged trampoline. Gives extra torsional stiffness to the boat and increases its aerodynamic characteristics.
• Patented main-sheet-wheel-system. For more direct and faster trim of the main sail.
• Aerodynamically placed traveller car.
• Flexible daggerboard casings. For minimal water absorption in floating mode.
• Aerodynamically shaped ‘beams’.
• Adjustable T-rudders. Foiling with rudder differential is possible.

Specifications

LOA: 5.49 m BOA: 2.30 m Max. draught: 1.20 m Sail area: 13.94 m Total weight: ca. 53 kg Top speed: 31 kn Extra: All measurements according to IACA Class regulations.

Buy a champion's boat!

Are you excited to buy a F1x A-class foiling catamaran from DNA Performance Sailing? Please fill in our contact form:

Yes, I want a F1x A-cat!

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SIT&FLY

you can  fly

THAT FLIES ALONE

Extended version on your desktop computer

A foiler designed for any sailor.

The idea was to create a SIT & FLY foiler, that is to say a boat with foils that practically flew alone, and endow it with an exceptional stability so that any sailor could fly easily, regardless of their physical or technical preparation, also allowing them to access into the competition with foils so far suitable for only a few specialists.

The mothquito foiling catamaran perfectly meets this objective. proof of this is that none of our riders had ever flown on a boat with foils before and as you will see in the videos they all fly without any difficulty. , i sincerely believe that it is the best guarantee that the mothquito is made for you., you will soon be able to try it for yourself. happy flight.

Designer and CEO:

IFS Foiling & MOTHQUITO

THE BOAT THAT FLIES ALONE

The Mothquito Foiling Catamaran is the first foiler in the world with an increased dynamic stability and performance, by the IFS system, a system that increases its dynamic length and beam to make foiling easy, safe and fun for any sailor.

Due to this system, the Mothquito surprises with its great stability, both at take-off and during flight, requiring the crew member simply the same physical effort that would be required to sail in any conventional dinghy boat without trapeze and without the need for a special technique.  

In the Mothquito you just have to sit down to sail and the boat will practically will flies alone.

For all these reasons, the Mothquito is an easy and suitable foiler for all types of sailors, a true SIT & FLY.

At the same time, it can be a fundamental tool for schools and training centers, which are increasingly in demand for easy-to-fly, stable, yet fast and fun foilers.

But make no mistake, the Mothquito is more than just a docile and stable foiler. The Mothquito is a high performance catamaran racer. With a dynamic beam in flight of 4.8 m2, this boat manages to significantly increase its righting moment, which allows it to have a sail area of ​​17.5 m2 in its basic configuration, to launch the boat at high speeds without heeling or feeling of risk.

With mothquito you don`t need:.

Previous experience.

Specific technical training.

Special physical preparation.

Navigate against heeling as in the Moth.

Hang on a trapeze compromising your safety.

Height sensors and flaps to regulate the flight height, since its V foils automatically regulate the height.

Increasing the dynamic length:

You increase longitudinal stability, improving dynamic longitudinal trim in flight and reducing the risk of nose dive and pitch poles., increasing the dynamic beam:, increased transverse stability is achieved, increasing righting moment and performance, with a significant reduction in heeling., that is why mothquito marks a before and after, a new concept in the world of foiling which is summarized in a single expression:, sit & fly.

With Mothquito you know how.

BACKGROUNDS

As foiling progresses, more and more fans and sailors want to experience the sensation of flying, even if only once.

But the reality is that many of them are in doubt as to whether they will be able to fly continuously and controlled, since flying these machines does not seem as easy as sitting down.

In many cases, it requires significant physical preparation and endurance to be able to keep the balance in flight based on counter-heeling, making counter balance and playing with the mainsail sheet hunting and molding to maintain balance and not repeatedly go overboard.

In other cases, as in the majority of catamarans, it will be necessary to hang on the trapezoid to reduce the heeling, and at high speeds the maneuvers are very fast and precise, so the risk in these circumstances does not It exactly coincides with the idea of ​​enjoy it.

In summary we can group the current foilers into 3 large groups:

They are small foilers, monohull or multihull, for a single handed and they have a central inverted T-foil and another inverted T-foil in rudder on the same line. When they are monohull, flying on these boats without falling into the water is not easy. You have to establish a continuous balance by flying against heeling and keep your balance playing with the main sheet, and your weight.

In the case of multihulls, the outer hulls act as a float to stop preventing the overturns, as the small lateral wheels do on a bicycle when the child learns. but this solution does not eliminate the difficulty of the flight and slows down the speed of the boat every time the float enters into the water. they also use flaps with mechanical height sensors to control the flight height, and therefore require care and maintenance., they are dinghy catamarans for single or double handed and have four inverted t-foils., with a dynamic beam of around 2.5 m, which usually coincides with their hull beam, these foilers are much more stable than the 2t foils, but in them the use of trapezoids is usually common to compensate the heeling, which not everyone likes and less at high speeds., they also use flaps with mechanical height sensors to control the flight height, and therefore require care and maintenance., 2j + 2t foils, they are high-performance catamarans, of greater length and for more than two or three crew. it is common to see them compete on international circuits. their main foils are in j, which is the same as an underwater v when the boat heels, so they regulate the flight height without the need for flaps. they are very technical boats that require a lot of training and good physical shape. in addition they are not affordable since their price is usually not within the reach of every pockets..

If you are a training center or sailing school...

We are developing a strategic plan for the commercialization and international expansion of the Mothquito that may interest you.