Wind vane steering on a gaff cutter

[MINESAPINT2]

Hi,

I have a Tradewind 25 with windvane steering which when working is truly magical however there are many occasions when it just will not do the business. I have realised it is due to the clew of the main sail being very close to the vane especially under full sail. The situation improves when reefed.

The minimum gap between the clew and vane are 2 feet, 5 feet and 7 feet respectively, full sail / 1 reef / 2nd reef.

The issue is the vane is reading the deflected wind off the sail rather than the true apparent wind. I cannot think of a solution and guess ketches and yawls have similar problems.

Mike

 

[jamie N]

My vane's about 5' from the leech, and whilst I'm not sure whether it's being affected by the draft from the sail, it does require the boat to be very balanced for the vane to work.
A possibility for it working with a reef in could be that the wind is having a greater effect on the vane itself?
Good luck.

 

[MisterBaxter]

Presumably the situation is worst when sailing to windward, when the clew is closest to the wind vane? Some gaff cutters can be persuaded to sail themselves to windward with no wind vane, might it be worth experimenting with that? The set-up tends to involve sail trim that slightly reduces speed, unfortunately, being based around a slightly tighter jib and the main let out a little.
I had a gaffer that would sail itself to windward in some conditions, on a close reach more or less any time, and on a broad reach on occasion.

 

[geem]

Hi,

I have a Tradewind 25 with windvane steering which when working is truly magical however there are many occasions when it just will not do the business. I have realised it is due to the clew of the main sail being very close to the vane especially under full sail. The situation improves when reefed.

The minimum gap between the clew and vane are 2 feet, 5 feet and 7 feet respectively, full sail / 1 reef / 2nd reef.

The issue is the vane is reading the deflected wind off the sail rather than the true apparent wind. I cannot think of a solution and guess ketches and yawls have similar problems.

Mike

We have a ketch with a Windpilot self steering system. We don't get any interaction issues between the mizzen and the vane because we don't use the mizzen when we are closer than 50deg apparent. The mizzen has no performance advantage so we drop it. Off the wind the mizzen does give us a performance advantage but the boom is sheeted out sufficiently far such that the wash of the sail has no effect on the wind vane