How Did The Sailing Yacht Gitana Fly Across The Ocean?!?!?

Описание: 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.

This year’s event attracted a record fleet of 138 boat in six classes, including a record number of full-foiling boats that fly above the water.

The previous record set in 2018 was 7 days, 14 hours, 22 minutes by Francis Joyon on his 100 foot trimaran IDEC Sport.

Francis raced again this year to defend his title, but was overtaken by some newer full-foiling boats, including Edmund de Rothchild’s Gitana 17 skippered by Charles Caudrelier.

The key to 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.

Previous generations of ocean-racing trimarans like IDEC Sport had foils in their floats and T-foil rudders, which provided some lift, but generally didn’t lift the entire boat out of the water.

Some boats with this foil configuration, as we first saw in the 34th America’s Cup, do lift the entire boat out of the water, but this requires incredible concentration by the crew, which is fine for short day races, but not for longer ocean races which last several days.

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 added a ray foil on the central hull daggerboard.

The ray foil has an adjustable trailing edge, like the foil on this Moth sailing dingy, which can alter the lift produced to match the conditions and keep the boat balanced.

The ray foil can carry anywhere from 80% of the weight of the boat in lighter or downwind conditions to providing negative lift in brisk reaching 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.

The advantage against partial-foiling boats like IDEC Sport diminishes as the boat speed increases. IDEC Sport in its non-foiling 2016 configuration still has faster 24 hour runs than the full-foilers, but that was in far winder conditions, when the full-foilers would have needed to slow down to prevent foil cavitation, which happens at around 50 knots of boat speed.

The full-foilers have the greatest advantage in moderate wind conditions, where a non or partial foiling boat would be sailing say 25 knots, and they are sailing 31 knots, which we saw a lot of in this race.

In the end high average speed is what wins races, and by the time the full-foilers were approaching Guadalupe, they had created a significant gap of more than 650 nautical miles or 1,200 kilometers over the older generation boats.

Foils can actually slow you down in lighter conditions, like Charles Caudrelier on Gitana experienced on the leeward side of Guadalupe, when he was creeping along at 2.5 knots, while Francois Gabart on SVR Lazartigue chased him down at 28 knots.

Despite that frustratingly slow spot, Charles still maintained an average speed of 21.6 KT compared to Francis Joyon’s 19.4 KT on IDEC Sport four years earlier.

This was enough to set a new Route du Rhum record of 6D 19H 47M, smashing IDEC Sports record by more than 18 and a half hours!

Remarkably, despite lots of ocean racing experience on crewed boats, this was also Charles Caudrelier’s first solo ocean race, and you wouldn’t know it by his success.

This fact must be bittersweet for Francois Gabart on SVR Lazartigue, who was the favoured winner in 2018, but was overtaken by Francis Joyon on IDEC Sport in the final miles of the race. Francois Gabart also holds the solo around the world record, so Charles Caudrelier overcame some very significant competition.

Still, foiling or not, these Route de Rhum sailors are single-handing these massive boats for days on end, at speeds that few of us can comprehend.

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