Leopard 38/ Sunsail 384 named SAIL Magazines 2010 Best Boat – Cruising Multihull Category
November 27, 2009
SAIL Magazine Best Boats
Click here to read more about the Leopard 38 (private owner customized yacht) and Sunsail 384
About Leopard Catamarans
Leopard Catamarans are built by Robertson and Caine. Founded in 1991, Robertson and Caine, were initially custom yacht builders. Over the years they built various different types and sizes from basic 36 foot fiberglass monohulls to state of the art carbon fiber racing boats up to 70 foot in size.
Leopard 38 Catamaran wins SAIL Magazine Boat of the Year 2010
Over the last 7 years they have been manufacturing 38 to 62 foot catamarans. In 1995, Robertson and Caine entered into a relationship with The Moorings, and more recently with Sunsail, to provide catamarans specially designed by Morrelli and Melvin for their worldwide fleets of bareboat and crewed yachts.
YCO signs Wally Yachts to build Aeroyacht 110
November 12, 2009
Morrelli & Melvin is excited to announce that Aeroyacht and YCO have signed Wally Yachts as the official shipyard for the new Aeroyacht 110.
Aeroyacht 110
Says Gregor Tarjan, the founder of Aeroyacht, “Wally is renowned for its groundbreaking designs, which constantly reinvent and reinterpret the traditional approach. Wally yachts are world class and stand alone both in performance and style. Given what we set out to achieve with the Aeroyacht 110, I don’t think there is a yard which could be better matched to us”.
Morrelli & Melvin look forward to working closely with Aeroyacht, Wally, and YCO in bringing life to this spectacular design.
Read more about this at
Sunsail 384 Shines in the Cruising Market
November 12, 2009
Sunsail put Morrelli & Melvin and Robertson and Caine to the test to design the first of a new generation of simple-to-operate high performance cruising catamarans exclusively for its cruising market. We developed an entry-level catamaran that appeals to first timers and has a generous sail plan that will also excite the more experienced sailor. The Sunsail 384 has something for everyone, and it’s less than 40 feet in length.
This catamaran was designed for the Mediterranean cruising market and kicking back and relaxing in idyllic coves and bays of the Mediterranean. In no time, it has proven to be so popular that Sunsail has made them available in the Bahamas, Caribbean, South Pacific and Indian Ocean too.
There’s fun in numbers and we planned the interior so that there are four double cabins and two forepeak berths. Those forepeak berths are great for kids or additional storage. Performance, comfort, tons of outdoor space and generous sail area are packaged in this roomy sailing catamaran.
We’re proud of the eco-friendly features that we’ve packed into this smooth riding, high capacity cruising boat. The Sunsail 384 is the first cruising fleet equipped with solar cells. The solar panels are installed on the bimini hardtop and will save an estimated 20 per cent on engine hours, increasing the lifespan of the onboard batteries by up to five years.
It was critical that the team used durable materials to withstand long seasons in popular cruising markets. The tooling was built in China and shipped to South Africa, and we used GRP construction with balsa core for strength, stiffness and insulation in the hulls.
Gino is going to be in Nice, France on November 13 -14 to help introduce the Sunsail 384 to cruising brokers and the media. Will he do a sea trial while he is there? Bien sur.
Always game to sail something new and different, our friend, Lynn Fitzpatrick, has promised us that she will check out one of the first boats to arrive in the Caribbean. Check back before the holidays for her update.
Getting Up to Speed on Foils
November 4, 2009
By Lynn Fitzpatrick and Gino Morrelli
Chances are if you have spent most of your life cruising around on a sailboat, you know a bit about what makes sails work. Foils, canards and wings, however, may mystify you.
Imagine this daggerboard suspended from the leeward hull. The bottom hook provides upward lift and the more vertical section (the transition toward the hook in the other direction) provides lateral lift/resistance.
We’ve tried to simplify the principals for those of you who have a phobia for math, physics and applied sciences. What follows is enough to make you dangerous. Leave the applications of these principals to experts such as Morrelli & Melvin, who have rocket scientists, naval architects and engineers on staff.
Power Lifting with Bernouilli’s Theorem
Bernouilli’s Theorem is also known as the longer path explanation. A sail is an airfoil. Viewed in cross section, one side of the foil/sail is longer than the other. As the foil moves through air, the air splits at the leading edge (mast or headstay) of the curved airfoil. The air taking a longer path by passing along the backside/leeward side moves faster than the air passing across the front/weather side. The particles moving across the backside/leeward side of the sail are traveling farther in the same amount of time and they have a higher velocity, or speed, than the particles on the front side/weather side of the sail. They also have more room to spread out, forming a low-pressure area.
On the front side/weather side of the sail, the slower air particles are packed together more densely, creating a higher-pressure area. This difference in the pressure on either side of the sail creates a suction force, producing lift/power that makes the boat move forward… therefore sailing sucks!
Rudders, Keels or Daggerboards Create Side Force
All boats have rudders and keels or daggerboards that are essentially vertical airfoils underwater. The symmetric rudder creates lift by turning slightly relative to the flow, also called “angle of attack”. This slight rotation creates just enough difference in the distance the water has to travel around one side of the foil as compared to the other that it creates the same effect as air passing around a sail. The more we turn the rudder, or increase angle of attack, the greater differential in distance that water has to travel around one side versus the other, the more power we get and the faster we turn.
The primary job of a keel or daggerboard is to create enough equal and opposite side force or lift to counteract the forces created by the sails aloft. Sails push one way and the keels/daggerboards push the other way, and essentially spitting the boat forward like a watermelon seed pinched between your fingers!
In a traditional monohull the keel has to do the other equally important job of providing stability by suspending a ballast down low to counteract the heeling/tipping forces caused by the sails aloft. Rather than rely on deep and/or heavy keels, cats’ and tris’ stability comes from placing the hulls far apart.
Lifting Hydrofoils Push Boats Up
The same basic principles that apply to airfoils/sails, apply to all underwater hydrofoils. Rudders are symmetric vertical hydrofoils that turn the boat. Lifting hydrofoils are mounted horizontally and try to lift the boat. A typical asymmetric lifting hydrofoil on a boat is positioned similar to a wing on an airplane with the shorter/flatter side down and the curved side up. Because hydrofoils are much thicker than sails and the density of water is about 800 times the density of air, they are way more powerful for the same surface area.
Hydrofoil assisted boats float on the water while at rest. At low speeds they are not necessarily any faster than boats without hydrofoils. As speed increases, the hydrofoils generate more and more lift and push the hulls higher and higher out of the water. The hull is sometimes completely supported above the water surface by a strut. Free of the drag caused by the hull, a hydrofoil boat can skim over the surface of the water at over two times the speed of boats without hydrofoils.
Alinghi, Le Bouveret, Lake Geneva - 20/07/2009
Curved Lifting Hydrofoils do Both
Both the BMW ORACLE trimaran and Alinghi catamaran use curved daggerboards (hydrofoils) to provide necessary lateral lift/resistance and they also lift the leeward hull up. The same board is used to reduce sliding to leeward or leeway and also provide vertical lift. The current variations that are being experimented with by both teams, tradeoff more vertical lift for less lateral lift or vice versa. Upwind these boats still need a fair amount of lateral lift/resistance to prevent excess leeway due to their enormous sail plans and the fact that they essentially are always going upwind! These boats sail at apparent wind angles downwind that are only about 10 degrees more than upwind! Downwind the sails are never really eased and the apparent wind never goes very far aft… the wind is always in your face on these boats! The apparent wind is so far forward on these boats that you always feel as if you are going upwind.
Combining both jobs, lateral resistance and lifting the boat into one board simplifies the boat but complicates the parts. Both teams are playing with variations of “J” or “L” boards, constant arc boards or even crazy looking “S” boards. Each shape has its slight advantages and disadvantages. They are also playing with different foil section shapes, which can produce better results at different speeds.
Racing sailors are always looking for the optimum combination of maximum lift for minimum drag. Both America’s Cup teams can raise and lower the boards to vary the surface area. They can seek more advantage by jibing them (changing angle of attack relative to the boat) and also rocking them fore and aft. Doing this, however, requires complex hull and board casing construction.
The buildup for the America’s Cup is a time for research and development, design and testing. Each team will have a matrix of foil combinations optimized for forecast wind and sea conditions. Their racing arsenal is much larger than that needed for cruising and performance/cruising multihulls to sail fast, comfortably and safely across a range of conditions.
The Morrelli & Melvin team is currently including curved lifting hydrofoils on our new Nacra F20 Carbon design and curved lifting hydrofoils will be appearing shortly on other new and exciting toys we are working on. We’re participating in BMW ORACLE’s America’s Cup developments and conscientiously incorporating design enhancements into our recreational and commercial power and sailboat designs.
Hands-On innovation at Morrelli & Melvin
November 4, 2009
A common attribute among designers and engineers at Morrelli & Melvin is the ability to build what they design. We believe that the hands-on experience enables our team to not only design products that can be built efficiently and economically, but also leads to innovation in materials and construction methods.
Gino Morrelli started out working on racing cars and boats in his family’s back yard as a teenager. He built his first boat with his dad and brother, a 33-foot Crowther trimaran in high school. Soon after he started his first company, Climax Catamarans, designing and building 18-square meter cats. He has been entrenched in onshore and offshore race-boat construction efforts since the early 80’s, managing and participating in the construction of 60’ ocean racing catamarans, Formula 40’s, the 1988 Stars & Stripes America’s Cup catamaran and many racing beach catamarans. Today he manages the Product Development side of our business where he helps bridge the gap between design engineering and our customers’ production lines. His many years of experience in racing, design, as well as on the shop floor, help us design boats that are beautiful, perform well, and are practical and economical to construct.
Pete Melvin has been creating innovative vehicles since his youth. Not discouraged when the boat he built as a 6-year old did not float, he rebounded and built a fast motorized skateboard by the time he was 10. Pete and his father designed and built several Optimist dinghies and then formed a company to build them. They used Nomex honeycomb and carbon fiber long before these materials gained acceptance in the marine industry. Pete has always designed, built, rigged, and prepared his own race boats, creating many innovations along the way and gaining valuable hands-on experience. He recently designed and built an innovative electric motorcycle that goes 50 miles on a single charge at up to 60 mph. His motorcycle is a test bed for lithium battery and electric propulsion systems that are increasingly finding their way onto M&M’s commercial, military, and pleasure boat designs.
“Consequences” / Wing Sails – Seahorse Magazine
November 3, 2009
Seahorse Yacht Racing Magazine - Jan 2009
Bob Covarrubias in Seahorse Magazine takes a look at using wing sail technology since it was famously used 20 years ago on Dennis Connor’s 1988 America’s Cup catamaran. Bob analyzes current uses of the wing sail by Harbor Wing Technologies for the US Navy and coastal security, as well as interviewing Pete Melvin, of Morrell & Melvin, about the other advantageous opportunities for hard airfoils on yachts and commercial ocean vessels.
Taking Wing – Boat International USA Magazine
November 3, 2009
Taking Wing by Lynn Fitzpatrick, Boat International USA, Jan - Feb 2009
Taking Wing by Lynn Fitzpatrick features illustrates how the wing sail has become a useful technology not only in America’s Cup racing yachts, but prototype and future industrial marine designs for Harbor Wing Technologies.
Read how everyone from the US Navy to BMW Oracle Racing are taking a serious look at wing sail technology.
Boats International USA in the January / February 2009 Reprint (1.6 MB, PDF)
