Why forestay SAG is a critical factor in upwind speed

Why forestay SAG is a critical factor in upwind speed

Getting the optimum speed and performance from your yacht, especially upwind, comes down to a combination of many factors. 

One of the most important variables is forestay ‘sag’, but why is this so critical?

Eddie Warden-Owen, RORC CEO, former sailmaker and America’s Cup coach explains:

“Forestay sag is a key part of controlling the aero-shape of the headsail and enables you to create different sail shapes for different wind conditions. Modern material is less stretchy and allows a sail to be used through a much wider wind range. 

Forestay sag is measured by forestay load, and controlled by rig and backstays. More sag equals deeper headsail and more power. Less sag equals flatter headsail for stronger wind.

Accurate knowledge of forestay sag enables you to repeatably adjust this to give known optimum sail shape for best performance throughout the race. Finding the right shape is achieved by trial and error or working with your sailmaker who can provide feedback on the photos you take.”

So, how to measure forestay load accurately and repeatably? 

For many years, most of us have relied on ‘low-tech’ solutions such as pieces of tape, rulers and pen marks on the deck, which seems more than a little out of place in 2019! 

This is why we’ve created Smartune, a new sensor technology that wirelessly measures forestay load and displays the numbers live on the boat’s instruments. This allows crews to adjust the load (and hence the sail shape) in response to wind conditions as they race. 

Simple to retro-fit, the Smartune Uno package consists of a wireless forestay load sensor, which simply screws into the forestay as a direct replacement for the existing turnscrew, and sends data wirelessly to the instrumentation gateway mounted below decks. This plugs data directly into NMEA2000 systems and can also send live data to smartphones over WiFi. 

Ultimately, it’s all about helping to get the boat moving fast, then keeping it fast as well – giving you maximum enjoyment and pleasure.

Smartune Testing Update

Smartune Testing Update

This summer, we’ve been testing our new Smartune forestay load sensors (which are the result of 12 months of product development) including on the water testing across the Northern Hemisphere.

We have had multiple units under design review in Europe and the US in order to get the design and requirements perfectly suited to the marine environment and the needs of the yachts and sailors.

Working with racing fleets and some of the leading yachts and sailors, we asked them to “test it to destruction” – and they certainly did that!

Some of our testing “highlights” came to life during the J/Cup, J/111 Worlds, the Fastnet and of course during the “The Big Blow at Cowes Week” earlier this month.

There were only a few breakages out of the many hundreds of hours of sailing that were completed, with one issue during Cowes Week where one of the testing yachts managed to blow apart the plastic casing of the Smartune unit, due to a spinnaker sheet being trapped. However, the good news is the structural integrity of the unit and the rig was not compromised.

Thanks to this testing and customer feedback, we are now working on design improvements including adding an anti-snag guard to the unit and improved water proofing.

So, a big thanks from us to our all product testers and champions this season. We would also like to acknowledge all the help, feedback and design requests from the wider sailing community.

We will soon be officially launching the Smartune Uno forestay sensor kit to the general market – watch this space for news of that and enjoy the last few weeks of this wonderful sailing season!

(Photo Credit: Cowes Week)

Innovation for a competitive edge

Innovation for a competitive edge

Last month’s YBW had a fun roundup of the top 10 innovations in the history of sailing. All good contentious stuff (although I suspect no-one would argue with the invention of the keel).

Sailing has always attracted innovators, particularly in racing. In particular, the rate of innovation in design and materials has accelerated so much over the past 20 years it is possible to date Grand Prix yachts within a year or two from a quick glance. The industry has enthusiastically embraced the use of data as well; GPS, depth sounders, knot meters, anemometers are all part and parcel of a well equipped boat.

Now it’s the turn of the next generation of data – real time feedback on the performance of the yacht structure – to help design and sail faster, safer boats. Borrowing from the worlds of motorsports and mission critical assets to deliver high accuracy data on the loads a yacht experiences. Using condition based monitoring and predictive analytics to explore how these loads affect performance and lifetime of yachts, rigs and foils.

This is the goal for Cyclops Marine. Bringing the best of professional innovation and engineering to bear on this opportunity, we’re aiming to provide a tool that lets crews, designers and manufacturers push the envelope even further.

And maybe even make it onto the list of sailing’s greatest innovations.