Wind Vane Operation
The Hebridean is a servo-pendulum wind vane. The vane detects a change in wind direction when the boat is off course. With the boat sailing, the flow of water provides the power to steer the boat.
The vane is mounted on a vane base at the top of the wind vane and has a push rod connection with the pendulum that slopes 32 degrees aft and into the water.
With the boat on course, the pendulum is in line with the water flow and the vane edge on into wind and upright.
With the boat off course, the wind is more on one side of the vane than the other, so it deflects rotating the pendulum in the water. Because of the flow, the pendulum swings to the side pulling lines to the tiller (or wheel) correcting course.
Changing course relative to the wind is done by rotating the vane base either manually at the stern, or remotely (as provided in the optional extra kit) by pulling a rope from the comfort of the cockpit.
A “drum” kit designed specifically for a Hebridean (but can be adapted for other wind vanes) is also available for boats with wheel steering.
Wind Vane Design Features
Storage in a boat locker is possible with pendulum diconnected from a frame folded flat.
Weighing only 12 kg, the Hebridean is easy to lift off and on the socket as needed and will not put a boat out of balance, even if small (less than 10 metres in length) and of light displacement. Nor will it put stress on the transom when pounding through waves in heavy weather.
For simplicity, the vane and the pendulum are both mounted on a wooden frame that pivots as a whole in a socket fixed to the boat. The necessary link between the two for the vane to rotate the pendulum (and counter-rotate it to prevent over-steering), requires nothing more than a carbon fibre push-rod and lever. The frames of other wind vanes are fixed solid to the transom and for the link, they require specialised machined cogs mounted on friction-free bearings to control steering, which is one reason why they are expensive and vulnerable to salt deposits that create friction.
Damping the vane to prevent over-steering is by “feed back” from pendulum swing and is a unique feature of a Hebridean.