Reflex Reaction
Harken has been quick to respond to the growth of cable-less headsails to ensure the gains extend beyond better sail designs
The ability to furl sails has been something we’ve taken for granted for at least 40 years. In fact, the influence of furling has been so widespread that it’s easy to imagine that everything that could be achieved has already been achieved. Except now we are finding out that it hasn’t and the next step in the evolution could represent another huge step forwards for the sport as a whole once again.
For Harken, the route began with the development of their Reflex Top- Down Free-Flying Sail Furling System for downwind sails. From the start, this was a system that was aimed at the broad sailing market and intended to enable recreational racers and short-handed cruisers to furl their asymmetrical kites and code-style sails completely and reliably so that they simply used them more often.
The system uses a torsion cable constructed from a standard polyester core (subsequently augmented by a Dyneema-cored version) and sheathed with a unique, covered stainless steel mesh, around which the sail is furled and unfurled
72 SEAHORSE
as the control line is operated. Pulling the furling line rotates the compact drive unit and the torsion cable, which in turn transfers the torque immediately to the head. The head swivel reacts instantly and the sail is furled around the stay. One of the key design features was to create a system that had low friction ensuring that furling could be an easy manual operation. Utilising Harken’s famously free-rolling open- race Delrin bearings provided the perfect solution.
Meanwhile, in the sailmaking world, Doyle and North were investigating whether it was possible to remove the luff cable from their downwind furling sails. Both could see the advantages of dispensing with the need for a torsion cable by designing and building code sails that could carry the dispersed load from the tack to the head within the structure of the sail.
At the same time, the shape of their sails saw more pronounced luffs that are projected to windward to
create a straighter luff for a fraction of the load that would have been required in conventional systems
Above: Harkenʼs new Reflex Top-Down Free-Flying Sail Furling System has been developed in parallel with the latest code sail designs by Doyle and North, which donʼt have luff cables. Together, these major advances in sail and furler technology enable sails to fly and work more efficiently with much less load on the boat and rig while remaining easy to furl by hand
using cables under tension. The increased performance of the sails took little time to confirm, while the reduction in loads was dramatic. Depending on the sail and specific boat, reductions in load at the tack of between 30-50 per cent were being reported.
It was at this point that the technology around these sails and Harken’s Reflex furling systems started to converge.
‘I was at St Barth’s Bucket sailing
on Blue Too with Richard Bouzaid and John Baxter from Doyle Sails and I was picking their brains about cable-less code sails,’ said Harken’s head engineer Steve Orlebeke. ‘It became clear that this technology was starting to trickle down into smaller boats. That got me thinking about how we could adapt our Reflex furlers to accommodate these sails.’ One of the key points that Orlebeke brought back from St Barth’s was that tack loads had come down considerably to a point that it was possible that the low friction Reflex furlers could be used without the torsion cable. From there, a small batch of
HARKEN
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