Southern Ocean at 30 knots

The giant trimaran Banque Populaire is reeling out 700-mile days in a fearsome display of the raw power of the wind


Thanks to the genius of orthopaedic surgeon Dominic Simon (go-to man should you ever need to have shoulder surgery), I'm back in the saddle again. Maybe not literally -  repeat mantra: 'must be patient' - but at least for some blogging duties.

One of the most exciting sailing adventures and achievements unfolding right now is the blistering, recordbreaking pace of the 130ft maxi trimaran Banque Populaire V. Today, a mere 23 days after leaving France and crossing the start line of the Jules Verne non-stop round the world course, the crew is well past New Zealand.

It's worth putting that in figures, as their progress is so astonishing. In a bit over three weeks at sea, Loïck Peyon and his 13 crew have covered around 17,000 miles, making a daily average of 700 miles. Right now, they are sitting at target speed, 27-29 knots, heading out across the Southern Pacific towards Cape Horn.

This is the right pace for a 45-day record (it currently stands at 48 days) and 'BPV' is three days, or 1,800 miles ahead of where the smaller trimaran Groupama 3 was at the same point on her record voyage.

To think that such speeds are possible under the power of the wind alone is still amazing.

This is a frighteningly powerful vessel. I sailed on board not long after the boat was launched in 2008. My over-riding memory of scorching round the coast of Brittany was the perpetual assault of apparent wind. The true wind was no more than 10-12 knots, not a white-cap in sight, but we were sailing at 25 knots and the apparent wind was nudging a yachtsman's gale. The crew told me that, day in day out, this is exhausting and energy-sapping.

When Groupama set her record, the body temperature of the crew was monitored in the Southern Ocean and although the helmsman was changed every hour, by the end of the stint, core body temperature had dropped by 1.5-2°C. On BPV a solid cuddy over the cockpit and windscreen on the aft beam fairing protect trimmers and helmsman but it is hard to keep crew properly defended from wind and spray.

British crewmember Brian Thompson recently reported that the boat needed to be slowed at times to prevent the structure being battered too much by wave impacts. Delamination is a big risk.

I remember finding the loads on the boat fearsome, even without the additional factor of sea state. The speed and strains extract an odd, percussive harmony and at times a deep hum resonates through the boat. To handle those loads four grinders are often needed. The 47m canting wingmast is moved to windward with hydraulic rams whose pumps are operated by the grinders. Each shroud sees loads of 24 tonnes.

This is an extremely technically complex boat. It has elliptical foils to reduce drag, pitching motion and create lift. Engineering such structures - each foil is made of 300kg of solid carbon - was complicated. No less so is keeping it all working and not over-stressing the boat under the ceaseless dynamic loads at sea.

The range of small things that could spiral into record-ending catastrophes doesn't bear thinking about, and as I watch the daily distances reel out I think of the tremendous skill and seamanship of Peyron and his crew. Having a fast boat is one thing. Keeping it at speed for so long quite another. 

Elaine Bunting's Blog

Find out what Elaine Bunting's been up to in her latest blog and add it to your favourites!