News

Doyle Sailmakers will be delivering the latest 58.4-meter Kokomo with the largest Stratis sails to date. The new Alloy Yacht designed by Dubois Naval Architects is fitted with the world’s 2^nd biggest carbon fiber mast at 75 meters tall. Doyle Sails New Zealand is fitting Kokomo with 3,000 square meters of Stratis sails.

Doyle Sailmakers have become one of the leading manufacturers of superyachts sails with 4 of the 5 finalists in this year's Superyacht awards sporting Doyle STRATIS™ sails. Doyle Sails head designer Richard Bouzaid explains the process for developing a STRATIS™ sail for a Superyacht, from the sail design and fit to the boat, through the engineering and manufacture of the STRATIS™ membrane at the 21,000 square foot temperature and humidity controlled plant in Auckland New Zealand.

As with any sail, the first stage in the process is the sizing of the sail. This is especially important on large yachts as errors are costly and often require cranes or the like to take sails on and off a yacht. Accurate measurements are required of all the parameters of the boat to ensure that this process is done correctly. Our first stage in the process is to build an accurate 3D model of the yacht within our design software. These models are accurate to millimeters and include all of the relevant detailing that can effect the fit and performance of the sail. The model shown below is the new 58 meter Dubois designed Kokomo.

These models include all details of the sail attachment points, furling units, head swivels, mast detail with halyard positions, spreaders and other potential conflicts with the sail such as communication equipment, genoa cars in potential positions, stanchions etc. This allows us to then fit a sail to the model and know with certainty that the sail will not only fit correctly to the 3 attachment points, namely head, tack and clew, but also where and if the sail will have other stress or chafe points due to fittings on the boat. They can then be suitably reinforced or the geometry altered to avoid this conflict. The accuracy of this type of modeling has been one of the biggest steps forward with sail design software in the last 10 years.

Shape optimization is the next stage in the sail design process. Base sail shape molds are used for certain geometries and applications and then adjusted for the requirements of the actual sail that is being designed, for example a cruising genoa will have more shape in the back to be more effective when the sheet is eased. During this process the sails will be accurately aligned to the actual attachment points so that mastbend and headstay sags can be incorporated into the sail design. Loadpath (custom fiber laid sails) as a sail is engineered to stretch a certain amount, rather than to a % of its ultimate breaking strength. For a high performing sail we would be typically looking for a maximum elongation anywhere in the membrane in the region of 0.15-0.2% and it is important that the elongation (stretch) is as uniform as possible in the membrane in all areas of use. This dictates how much fiber is required in any area of the sail. The graphic shows the stretch through the sail and where the sail has more stretch than the desired amount, shown green.

During this process of establishing the correct fiber alignment and density, different combination of fibers may be used to get the best balance between weight and overall durability. There are various fibers that we use in a STRATIS™ sail depending on the application. Performance cruising boats will typically use Vectran or a combination between Vectran and carbon fiber. Performance racing boats will use twaron (Kevlar), Carbon fiber or a combination of twaron and Carbon fiber.

Once the orientation of the fibers and the density has been finalized the fiber map for the sail will be programmed into the 12m wide x-y plotters that will lay these fibers onto the surface that will become one of the sides of the finished sail. These fibers are all laid under tension to exact paths determined by the earlier studies.

The final process in the membrane manufacture is the application of the top surface.This is also a film sheet, often with a polyester taffeta on the outside, and pre coated with glue. This is finally vacuum bagged to the table and the laminator, which uses infrared heat lamps and 12000KG of downward pressure. The laminator will then make computer controlled passes over the membrane to activate the glue and expel and remaining air in the laminate. The factory has 2 of this style of laminator operating. The membrane is left to cure for several days before being moved to the Doyle New Zealand 30,000 square foot sail loft floor for finishing, or shipping to one of the many Doyle Lofts worldwide for completion.

Labels: Stratis, Superyacht

Doyle sailmakers Matt Allen and Andrew Schneider took first place at this year’s Vanguard 15 Midwinters fleet race in Sarasota, Florida. Allen, the defending Midwinter Champion and class president, and Schneider, a two time All-American sailor, braved extreme weather conditions to win four races, placing first overall.

The Vanguard Midwinters are a two part event, featuring two days of fleet racing followed by three days of team racing. Initial weather was cold, with light to moderate wind conditions, but the second fleet day brought colder temperatures, heavy rain and thunder. Wind speeds stayed above 20 knots the entire day. Despite the conditions, Allen and Schneider managed to perform with consistency and excellence.

As an additional challenge, Allen and Schneider had never sailed together before. Although both are experienced sailors, “Sailing with someone new there are always little things you try and figure out different skippers like to do things differently,” says Schneider. Allen has more than ten years’ experience on the Vanguard 15 and three years as class president. He has been recognized as an All-American, winner of the Hinman in 2005 and spent six years coaching at Merchant Marine Academy, finishing his tenure there with four years as the head coach. Schneider is a two time All American, two time Boston College MVP and two time conference MVP.

Allen and Schneider also competed in the team racing with Charles Higgins, Stephanie Roble, Gordon Wolcott and Mike Komar. After two days, the team had ten group wins and six gold fleet wins, placing them third overall. However, the below freezing temperatures in Florida caused a case of frostbite to prevent them from sailing the third day, dropping them to a seventh place finish.

The Vanguard 15 Midwinters are a highly completive event, drawing some of the best dinghy sailors in the country. Allen and Schneider proved that they are masters of speed, tactics and maneuvering. Congratulations to Matt and Andrew!

Integrating High Performance Parallel Computing (HPC) with state-of-the art Computational Fluid Dynamics (CFD) and Structural Mechanics (FEA) software from industry leader ANSYS Doyle Sailmakers has recently begun utilizing a high resolution, fully coupled computational simulation environment designed specifically to answer real world sailing challenges.

The complex turbulent flow around sails, rigs, and hulls is calculated to solve for millions of data points in the flow surrounding the sails. The detailed stress distribution and deformation that results in the sails and rigs from the forces imposed by the flow is then calculated using a Structural Solver with a composites pre-processor to accurately model the complex overlapping fiber and panel layouts in modern sails.

As Jud Smith says: “I love the flow graphics, I don’t understand the process, but the results in improved sail performance are undeniable.”

Flow Visualization From Star CFD Upwind Simulation (AWA=22, AWS=15 kts)

To learn more about Doyle Star sails, click here.

To learn how the DOYLE Engineering Department optimized the sail shape for a boat 88 meters in overall length, with a mast height of 53 meters off the water and maximum yard length of 22 meters, read Tyler Doyle, DOYLE's head engineer, coauthored paper, Optimization of Yard Sectional Shape and Configuration for a Modern Clipper Ship.

Labels: Jud Smith, Maltese Falcon, Star, Tyler Doyle

By John Gimson

The Star pair look back at 2009 and their first full year of campaigning

Having just finished our first full year star sailing we felt it a good time to thank our sponsors and give a brief roundup of our season.

The start of the year was spent in Miami, we arrived in very early January a few weeks before Rolex Miami Olympic Classes Regatta, and trained with Jud Smith of Doyle Sails leading up to the regatta. As it was our first OCR in the Star, we had no idea where we would finish, or how quick we were going to be in our 9 year old boat! We finished 13th which we were relatively happy with as our first attempt at a star regatta.

The next event for us was the Bacardi Cup, which is the biggest annual event in the Star outside the World and European Championships. We set ourselves the goal of top 15 for this regatta, as this would be the result we would need to get at the Worlds or Europeans (later in the season) for continued support from the RYA, and an upgrade from the Skandia Team GBR Development Squad to the Performance Squad.

The Bacardi Cup is a very hard regatta as there are only 6 races normally 2½ hours long, with 1 discard, the same format as the Star Worlds. We hovered between 20th and 16th all week but didn’t pick up any really bad scores, then with a good last day we finished in 15th overall meeting our target. It also gave us a good idea of what we needed to work on to get another top 15 result at the Worlds and Europeans.

We then set ourselves a grueling schedule, with a regatta almost every other week from March till the end of July so we would be properly prepared for the Europeans and give ourselves the best chance of achieving our goal for 2009.

We went in to the Europeans wishing we had more time, but having finished top 15 in 5 out of the 6 regattas we did between Bacardi and the Euros we felt we had done all we could over the year to get the best result at this stage of our campaign in the given time, and hopefully continued support.

The good news for us was the regatta was going to be breezy, we had good pace over the season in the breeze and were happy with our sails and boat in this condition. We finished the Star Europeans in 11th overall and 8th European in the 93 boat strong fleet. This was a very pleasing result for us, and easily enough to progress into the performance squad and get the extra funding we badly needed.

Then back in the UK in the Skandia Sail for Gold Regatta, we finished 11th, an ok result but we both came away feeling slightly disappointed as gear failure in the final days racing moved us 1 place outside the top 10. But was enough to finish 10th in the ISAF Sailing World Cup.

We have just returned from Rio de Janeiro and the South American Championships. It was a very competitive 64 boat fleet, we were racing alongside 7 world champions and most of the top boats. After a bad start to the regatta we finished on a high scoring a 9th and 4th on the last day moving us in to what seems to be our average finishing position of 11th in 2009. This was followed by 3 weeks training as we our now preparing for the 2010 Worlds in Rio.

In line with our average of 11th place we finish the season 11th in the ISAF world rankings and know we have a lot of work to do in 2010 to move further up the fleet to get to where we want to be for the 2010 Skandia Sail for Gold Regatta which will be the Pre-Olympics, and what we are spending the next 9 months building up to.

Alongside Skandia Team GBR we have had a lot of support and would like to thank Eamonn O’Nolan for his ongoing support, Doyle sails for powering us and in particular Jud Smith for all of his input. Peter Harrison for providing us with our boat and of course Ian Barker for his coaching support.

Labels: One Design, Star