Symmetric vs Aysm Spinnaker - Driving

[roblpm]

Hi

Just went on a racing course using Asymmetric spinnakers. So now quite happy with turning down until pressure drops a bit on the spinnaker, then turning up slightly. Driver and trimmer talking about the pressure. Heating it up by turning up.

However my boat is Symmetric. So there are 2 variables, the course of the boat and the pole angle.

So what are the analogies for a symmetric spinnaker. If the pressure drops should the driver turn up? Or move the pole? I know the pole should be 90 degrees to the wind, but how often should you move the pole as opposed to steering differently?

Any ideas??

 

[lw395]

Generally don't move the pole much, except in the light stuff if a lull has slowed the boat, the wind will go forwards so the pole needs to go forwards.
If it's a wave that slowed the boat, the wind will go aft.

 

[mrming]

Bit of a side point, but, when tight reaching with a conventional kite, if we spot a gust coming I head up so that we can bear away when it hits, keeping the boat on her toes but maintaining our overall course to the mark.

 

[flaming]

Pole should rarely be still, but the principal is the same. Dive down when there is pressure in the sheet, head up when in goes light. However, once the wind is up it tends to result in just running straight with constant pressure.

 

[Judders]

We very rarely cleat the guy, almost never inshore. We also have a double purchase on the poledown so as to not have to close the clutch. It takes a lot of teamwork but our downwind performance is one of our strengths.

 

[Birdseye]

Where do you run the pole down to, Judders? We run ours ( 35ft boat) to the base of the mast because of the safety issue of taking it to mid foredeck. Too much to trip over for the foredeck crew.

 

[Judders]

We have a strongpoint in the middle of the foredeck. I don't think of it as being particularly unsafe I'm the context of this being the foredeck of a relatively light powerful 28' yacht that bounces around a bit.

 

[TallBuoy]

Where do you run the pole down to, Judders? We run ours ( 35ft boat) to the base of the mast because of the safety issue of taking it to mid foredeck. Too much to trip over for the foredeck crew.

on the 39, the pole-down goes to a pad eye in the middle of the foredeck, I think it was put there for the purpose some years ago. Not a major safety issue in the grand scheme of things, as Judders says.

 

[flaming]

Where do you run the pole down to, Judders? We run ours ( 35ft boat) to the base of the mast because of the safety issue of taking it to mid foredeck. Too much to trip over for the foredeck crew.

How do you hold the pole forward with that setup?

 

[Plevier]

Dive down when there is pressure in the sheet, head up when in goes light.

Anyone got a good reference explaining this in more detail please?

 

[lw395]

Anyone got a good reference explaining this in more detail please?

When the objective is max progress downwind, get the boat up to speed, then bear off as much as possible until the drop in speed becomes unacceptable.
Then head up to build more speed.
Sometimes you will find a sweet spot where you can hold a fast course for a long time, other times you may find it better to keep cycling between high and low of the best course.
If the breeze is fluctuating, then the trick is to work your course variation with the wind variation not against it.

Sailing in the harbour, it's often good to sail high, moving across the harbour a fair amount, until you find a 'lane of breeze' then, once the boat is going fast, bear off a lot, to stay in the lane.
The difficulty is working out whether you've sailed out the other side of the lane, or it's just a bit of a lull.

 

[flaming]

When the objective is max progress downwind, get the boat up to speed, then bear off as much as possible until the drop in speed becomes unacceptable.
Then head up to build more speed.
Sometimes you will find a sweet spot where you can hold a fast course for a long time, other times you may find it better to keep cycling between high and low of the best course.
If the breeze is fluctuating, then the trick is to work your course variation with the wind variation not against it.

Sailing in the harbour, it's often good to sail high, moving across the harbour a fair amount, until you find a 'lane of breeze' then, once the boat is going fast, bear off a lot, to stay in the lane.
The difficulty is working out whether you've sailed out the other side of the lane, or it's just a bit of a lull.

This is all absolutely true. However in a decent breeze (say 15kts plus) in displacement yachts you'll beat 99% of amateur crews by just polling back and pointing at the mark.

For the type of boats that most on here sail, angles are for light winds.

 

[Ceirwan]

With a symmetrical kite and a non planing displacement boat, with any kind of breeze you'll be better heading straight for the mark if you're dead downwind.

As a good starting point (downwind) set the pole at right angles to the wind, I'd argue that its more important to be trimming the sheet than the guy, have a couple of turns (of the sheet) around a winch and then led up to someone stood on the windward deck who can see the luff of the spinnaker, the goal is to ease the sheet until it starts to curl over and try and hold it at that point.
If the spinnaker starts to collapse then sheet in in, if the luff stops curling then sheet out.

With any kind of breeze you'll need someone by the winch as well to grind in when the trimmer requests.