Sailboat cracks 100 km/h for first time
Anglo/Australian ‘Sailrocket’ blows away speed records with wind turbine tech
A sail-powered boat has cracked 100 km/h for the first time, thanks to a ‘Wing-Sail’ designed by a British consultancy that specialises in wind turbine design.
Sailrocket 2 set the record last week, and the speed 54.08 knots (100.1 km/h) the craft achieved has been recognised by the World Sailing Speed Record Council as the new mark in Class B for vessels traversing a 500 metre course. The speed is higher than any other vessel recorded in the Council’s lists and is the only recorded speed over 100 km/h.
The craft wrested the 500m record from the hands of kite-surfers, who enjoy the advantage of lighter craft and the ability to get sails higher into the air where winds are sometimes stronger. The Sailrocket, by contrast, has had to endure all sorts of strengthening in order to support its sail, touches the water at three points and allows someone to sit in it, instead of hanging on beneath a kite.
Sailrocket 2’s design relies on a single wing-sail, a rigid carbon fibre contraption set up specifically to catch the prevailing winds in Walvis Bay, Namibia. Last week those winds were gusting at around 27 knots, but the design of the wing-sail enabled the Sailrocket to proceed at a rather more rapid pace to claim the record, occasioning a triumphant tweet to the effect that the team 'smashed the arse off' the previous record.
The team has since claimed, in this blog post, to have yesterday averaged 55 knots (101.9 km/h) over a course one nautical mile in length, with peak speeds in the 60s. On that run, the team says it averaged 59 knots (109 km/h) over the 500m course. The Speed Record Council is yet to ratify those records, but the Sailrocket team seem confident they’ll extend their own 500m record and take the one nautical mile crown from the French sail-powered hydrofoil known as the ‘Hydroptère’.
Video of the one nautical mile run can be seen below.®
That is pretty damn rapid... It's mad enough doing that kind of speed in a powered water craft, but at least you have control of everything (bar the waves). Pulling that kind of speed at the mercy of the wind - mental!
It's also nice to see people in their rightful places too. Brits doing the design thing in their sheds, and a crazy Aussie piloting it. That's how it should be!
Or you could just go outside in a hurricane in a big coat - see diagram
Re: French sail-powered hydrofoil known as the ‘Hydroptère’
Hydroptere is basically just a brute force solution though.
I had a large slice of humble pie to eat when these guys hit their record, because when I saw their first craft I thought they didn't stand a prayer, but I spectacularly underestimated the level of committment and sustained effort the Sailrocket boys and girls were going to put into their project.
In many ways what these guys have done is roughly equivalent to breaking the sound barrier. For some time quite different sorts of high speed craft have been topping out around the 50knot region, because its about there you get into a phenomenum called cavitation where the blades that go in the water to control a craft create such low pressures around them that the water boils, and the things stop working.
The Sailrocket guys have genuinely got through the cavitation region and beyond, which hasn't been done before on an unpowered craft, and its a hell of an achievement. The most difficult engineering on this thing is not in the air, but in the water, and you can't praise them enough for achieving it.