Tossing the wind vane

[Terra Nova]

A 60' Freya? Interesting!

[stillbuilding]

Originally Posted by Terra Nova

A 60' Freya? Interesting!

Will be interesting to see how effective it is. Is an easy yacht to balance but I expect sail trim will be crucial at this size. It had better work cos the first run is Aust to HK.
Will let you know how it performs.


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[Terra Nova]

If it has a wind vane you can post photos right here.

[AuroraGH]

I sailed the length of the west coast with a monitor and an autopilot. The monitor worked very well, I generally engage it as soon as the boat's sails are up and trimmed. Can't say the same for the autopilot. Constant problems.

I view electric autopilots as strictly for use while motoring. If there's wind, I can't be bothered to spend the electricity on something I can get for free.

[cwyckham]

Originally Posted by AuroraGH

I sailed the length of the west coast with a monitor and an autopilot. The monitor worked very well, I generally engage it as soon as the boat's sails are up and trimmed. Can't say the same for the autopilot. Constant problems.

I view electric autopilots as strictly for use while motoring. If there's wind, I can't be bothered to spend the electricity on something I can get for free.

Although I agree completely with your sentiment, I'd hardly call a windvane "free!"

[sailorboy1]

I use my autopilot most of the time when sailing. With proper sail trim it barely uses any power and isn't an issue to me at all with my 290W solar. I normally use a response setting of 2 or 3 (out of ten) to reduce the power use (and that is still holding a pretty tight course and much better than I can do by hand).

I think people complaining about high power use don't trim well (I normally have less than 5 degrees rudder), have the wrong autopilot, use too high a response, or a squirrelly boat.

[bobnlesley]

...people complaining about high power use don't trim well,...have the wrong autopilot, use too high a response, or a squirrelly boat.

Whilst I think there's a lot of truth in what you say, it has to be said that open ocean sailing, with big swells and the wind too coming from well abaft the beam - just the sort of conditions that you want/need for crossing oceans - are exactly the conditions which autohelms dislike the most and in which they become particularly power hungry; that's why we have a windvane steering (Monitor) fitted and why I wouldn't contemplate undertaking a short-handed passage without it. Coastal sailing or island-hopping, I think it'd be har to justify the upfront cost of a windy, but for oceans, they're the way to go: If we were two days out, with two weeks to go and the engine died, that'd be a distraction, if the fridge died, that'd count as irritating, but if we lost the Monitor, we'd count that as having a serious problem; if our autohelm-unit died I similar circumstances, well... it'd probably be 13.75 days before we ever realised that it was busted.

[bobnlesley]

Over the last few years I've seen many more Hydrovanes and Cap Horns than Monitors... I think taking bits of string back to your wheel is a bit 'passe' these days.

From what I've seen, I'd have to disagree, though I did see an article concerning ARC Rally boats recently which suggested things may be going that way. Personally, I believe that the servo-pendulum units are more powerful and quicker re-acting (I'll be surprised if someone doesn't contradict me on that sooner rather than later) than the Hydrovanes, but the longer those strings get, the poorer its performance will be - doesn't matter what type of string/how you tension it, it's just physics and can't be helped. So as boats get ever bigger and are more often built with a centre cockpit too, the servo-pendulum vanes need longer lines to connect and so their advantage in steering power/response is increasingly reduced; if I got a centre-cockpit yacht, then I too might choose a Hydrovane?

Again, I think it's this general increase in yacht size that's also seeing yachts move from wind to electric powered self-steering. As an example, the Monitor unit we have apparently works on boats up to 70' and whilst I'm sure that it does, I'm also sure that it can't steer said 30 tonne/70' yacht as effectively as it steers our 7 tonne/35-footer.

[colemj]

Originally Posted by bobnlesley

it has to be said that open ocean sailing, with big swells and the wind too coming from well abaft the beam - just the sort of conditions that you want/need for crossing oceans - are exactly the conditions which autohelms dislike the most and in which they become particularly power hungry

This is much less true with current modern autopilots. The rate compasses and steering algorithms are such that they actually anticipate pitch, yaw and acceleration/deceleration. They make rudder changes before the forces become high and correct their steering before the boat goes off. This doesn't require much more power than steering in light conditions. In 30kt 10' following seas, our pilot uses ~4A, while the boat stays steady on course.

Older pilots could only react to conditions and they sawed back and forth using a lot of power. Our old pilot used 13-17A in the above conditions, while the boat yawed around reacting to the conditions after the fact.

I am always surprised to sit at the helm during these conditions with my hand lightly on the wheel pretending I was steering. The moment I "apply" an anticipated correction at the top or bottom of a wave, the AP moves the wheel in the direction and amount I would have.

Mark

[K_V_B]

Originally Posted by colemj

I am always surprised to sit at the helm during these conditions with my hand lightly on the wheel pretending I was steering. The moment I "apply" an anticipated correction at the top or bottom of a wave, the AP moves the wheel in the direction and amount I would have.



Mark

Interesting. What pilot do you have?


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[colemj]

Simrad AC42. I suspect most of the new pilots will be similar, with the B&G H5000 and NKE being even better in this regard.

Mark