SailRocket update

Merchant of speed Paul Larsen describes his new rig

The SailRocket project is set to hit the water again for Weymouth Speed Week next week (8-14 October) in an effort to climb ever closer to its ultimate goal to be the fastest yacht on the planet. Her new solid wing sail which was always planned for SailRocket is now entering the final stages of design. Machined moulds have been delivered and the build will commence shortly after Weymouth Speed Week.

With only a couple of days sailing posted since last year, we have been busy working in order to fund* (see below) the future of the project while developing the next exciting stage, the construction of the solid wing sail. This will provide a substantial increase in performance.

The solid wing is a very tricky piece of kit to design and build. It has to be extremely well thought out in order to both perform and survive the rigours of a speed sailing program. This 'sail' needs to hold optimum shape in apparent wind strengths of over 50 knots. It will have around a ton of load upon it and yet it must be very light. It must be easy to handle on the land and on the water. It will have flaps to control the centre of effort and it needs to be used on either port or starboard tack. It must be robust

Chris Hornzee-Jones, director of Aerotrope has designed the versatile wing and has done a great job. The wing will have a non load-bearing composite moulded leading edge section using SP Composite materials and Designcraft know-how in order to take the highest aerodynamic loads without distorting. The Compotech internal carbon spar will be the backbone and take all the bending loads whilst making the wing structurally robust. Joining the two and giving the whole wing its shape will be the Fibrefusion ribs. Due to the loads there will be a lot of ribs (33 primary and secondary). They have to be light and right to handle bumps and knocks without compromising strength.



Fibrefusion are a welcome addition to the project with, among other things, their ability to manufacture high quality, custom composite panels which they then water jet cut to exact tolerances. Behind the composite leading edge, high strength heat shrink plastic will define the shape. There will be full-length flaps along the trailing edge so twist can be put into the wing in order to position the centre of effort where we want it. The wing is symmetrical in shape span-wise as we are not counting on any end-plate effect with the surface of the water and it allows the wing to be 'end for ended' to sail on either tack. The solid sail is only 16sqm as against 22sqm for the current soft sail.

Once again the SailRocket project has received the necessary support from sponsors old and new and we are delighted to showcase the next stage in our quest to set the pace in speed sailing.

The lessons learnt with the Compotech-Doyle soft rig have been invaluable and paved the way for the solid sail as planned. We are now very familiar with the workings of this totally unique craft and mistakes have been cheap. This would not have been the case if we started with the solid wing from day one. We are still learning and will continue to sail with the Compotech-Doyle soft rig in order to refine the platform and our teamwork in handling such an unusual craft. The Mk1 sail has undergone many modifications along the way and we can't thank Phil and Daryl at Doyle UK enough for their enthusiasm and support to date. I'm sure we will wring even more speed out of it before it's done!

So it's still all go here at SailRocket. In terms of overall project progression, we are along way down the track. In outright speed sailing terms, at 31 knots we are just beginning to walk. The addition of the solid wing sail should take us the rest of the way. If we didn't think we could do it, we wouldn't be doing it.

Cheers, Paul.

*At one point, earlier this year, I even travelled to faraway lands, took part in and won a real race around the very real world run by someone who promised some REAL guarenteed prize money. I met a real sheikh who handed me a gold envelope with what turned out to be pretend prize money. I know he was real because I shook his hand. I used the pretend prize money to build a pretend new sail but trials with the pretend sail have been disappointing so we will return to the real world and build a real sail. Sometimes I still wonder - what was all that about?

Meanwhile the SailRocket project continues to look for suitable REAL title sponsors. Don't wait until after we've done it, because we'll get cocky and charge more. It's the way of the world.