What were John Fleming’s innovations after exactly 60 years of reliable servo-pendulum wind vane self-steering?

Technical innovation summary

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.