vane gears

A few weeks ago I pondered the very high loads that auxiliary-rudder self-steering gears put on themselves and the parts of the boat they are bolted to, based on the failure of Simon Curwen’s Hydrovane gear while leading the GGR.

Now we are getting reports that Abhilash Tomy is having a hell of a time keeping his Windpilot servo-pendulum gear operational.

As I understand it, both Abhilash and Simon started having big time trouble with their gears when they got in really nasty weather west of Cape Horn and got broached repeatedly.

Obviously, this is a small sample, but I think the takeaway might be that no vane gear is going to consistently stand up to broaches in big seas, no matter how well made. Seems logical.

And, further, that the idea that a servo-pendulum gear will kick out of the water and unload before damage is done might not be true, at least in really big seas.

And this in turn makes it even more important to have storm survival gear aboard, a strategy in place to prevent broaches, and the ability to get through really nasty storms without steering and with the vane gear safely out of the water.

Of course, as I understand it, that last requirement is easy to execute with the Windpilot and Cape Horn, and very difficult with gears like the Hydrovane.

On the other hand, the Hydrovanes seem to have done better than the Windpilot in this and the last GGR, aside from Curwen’s unfortunate experience.

Again, nothing definitive here, but worth thinking about when we are selecting a vane gear.

I think, on balance, I would select one that I could easily pivot out of the water.

I was really saddened to hear that Golden Globe Race leader Simon Curwen is probably out of the race due to a catastrophic failure of his auxiliary rudder self-steering gear in a broach.

I have long wondered if these gears that actually steer the boat with a separate rudder, rather than control the main rudder as servo pendulum gears like the Windpilot and Cape Horn do, are a good idea.

After all, the rudder and its attachment are one of the most strongly engineered parts of a good offshore boat. So does it really make sense to try and steer the boat with a comparatively flimsy rudder bolted onto the transom?

The other worry is that, even if the gear is up to the job, huge loads are being transferred to the transom, which was probably not engineered by the original naval architect, or builder, to take them.

There is even a suggestion, albeit by a source with an axe to grind, that it was exactly this problem that caused a sudden break up and sinking of another boat in the same race.

And, finally, auxiliary steering gears can’t pivot out of the water and thereby unload in a knock down the way some servo pendulum gears can.

Nothing definitive in all of the above, but definitely something to think about when selecting a vane gear.

Thanks to AAC European Correspondent Colin Speedie for the head’s up and some of the above thoughts.

Much more on self-steering, both vane gear and autopilots.