Hebridean Wind Vane Design Features
Storage in a boat locker is possible with pendulum disconnected 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 an angled socket fixed to the boat. The link between the two, for the vane to rotate the pendulum (and counter-rotate it to prevent over-steering), is 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 the pendulum swing and is a unique feature of the Hebridean.
Technical innovation summary
Ian Kirkwood, 2024
John Fleming’s crucial twin design innovations incorporated in the Hebridean are seminal:
1. The solution combines frame and pendulum in a single simple unit that can be removed and stored when not required.
2. To enable full power and sensitivity across its range of movement the Hebridean permits the efficient use of a true horizontal vane axle for the first time in 60 years.
Together, these two innovative design elements – each dependent on the other – represent a significant development in servo pendulum wind vane self steering options. Complex high-maintenance engineered links between vane and pendulum are no longer mandatory. Nor are specialised low stretch lines and low friction blocks crucial. Marcel Gianoli’s 15-20 degrees offset ‘horizontal’ vane axle has featured on all servo-pendulum wind vanes since the ECA engineer’s angled axle solution first rendered the concept reliable. And what a leap forward that was, contributing to Eric Tabarly’s 1964 OSTAR victory aboard Penduick II.
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