How Do The Monsters Of The Route Du Rhum Fly Above The Water?!?!?

The Route du Rhum is a single-handed transatlantic sailing race which takes place every four years from St. Malo France to Guadalupe, and covers a distance of just over 3,500 nautical miles, or 6,500 kilometers. The current record is 7 days, 14 hours, 22 minutes, held by Francis Joyon on his 100 foot Ultime trimaran IDEC Sport. Francis is racing again this year to defend his title, but there are a couple of newer full-foiling Ultime front-runners who are currently in the lead - Edmund de Rothchild's Gitana 17 skippered by Charles Caudrelier and SVR Lazartigue skippered by Francois Gabart. Francois Gabart currently holds the solo around-the-world record of 42 days, 16 hours, 41 minutes, which is less than two days slower than the overall around-the-world record set by Francis Joyon and his crew on IDEC Sport. The key to Gitana and SVR Lazartigue's blistering speed is their ability to fly above the water on foils, which reduces drag from the waves and water, and allows them to sail 10-20% faster in moderate wind conditions. But how exactly do these 100 foot Ultime monsters fly above the water for extended periods of time? These boats have numerous foils and appendages that stick down into the water, two on each hull to be precise. Lifting C or L-shaped foils and T-foil rudders have been seen on multihull floats for several years now, as we first saw in the 34th America's Cup, and on Francis Joyon's IDEC sport from the last Route du Rhum, but these generally aren't sufficient for full-foiling in open ocean conditions. To stay balanced, the foils have to provide the exact amount of lift required to counter the heeling forces of the wind. To add ocean-going stability several of the Ultime trimarans have added a ray foil on the central hull daggerboard. The ray foil has an adjustable trailing edge which can alter the lift produced to match the conditions and keep the boat balanced. In moderate winds, it provides a substantial amount of lift, and as the wind increases the ray foil lift is reduced as a higher percentage of the boats weight is carried by the float foils. The ray foil lift can even be made negative to hold the centre hull down in very windy conditions! Even though the ray foil is adjustable, it is more like a trim setting and set for the average conditions at the time, and the boat is kept balanced in gusts and lulls by steering by steering up or down relative to a beam reach. These full-foiling monsters have the greatest advantage in moderate wind conditions, where a non-foiling boat would be sailing say 22 knots, and they are sailing 28 knots. As the wind and boat speed increases the advantages of full-foiling diminish as the boats approach the cavitation speed limit of the foils at around 50 knots, where the water literally boils around the foils, resulting in reduced lift, high drag, and even damage to the foils. This video includes content for educational purposes under fair use: Disclaimer: - This content is offered solely for your education and entertainment. - There are no warranties, expressed or implicit, about any content or its fitness for a particular purpose. - There are risks of injury, death, drunkenness, and financial hardship involved in sailing. - The skipper is always responsible for the safety of their vessel and crew. - Sailing Tips is not responsible or liable in any way for anything that happens on or anywhere near your boat or any boat that we are not in command of. #sailing #foiling #howtosail #learntosail #sailingtips