Round up with Spinnaker

[grantgoulding]

I am fairly new to sailing our boat (42DS) with a spinnaker. We seem to find it becomes overpowered all too easily and I wondered if any one has any special tips to help prevent the problem of a gust causing us to round up. We are shallow draft which of course doesn't help. For example with a broad reach with 10 knots of wind we are fine then if we get a gust of 12-13 knots she will almost broach and become uncontrollable. As you can imagine this is not good news if you are near to any other yachts. Releasing the sheet a little does nothing to help. Any ideas as it means at the moment we have to be so sure the winds will stay below 10kt or otherwise not use the kite. Its a 1270sq ft Asymetric without a pole or bow sprit.
Thanks
Grant

[MalcolmP]

Hi Grant

We are also just learning with our new asymmetric which is a V5 from Quantum


We are also shallow draft (39i) but so far have not had a round up problem and have been flying it in 18knts apparent - took it down as I was getting nervy.

We have a the tack on a adjustable spi downhaul so can easily harden in or loosen when going further off the wind

Scott at Levington, is a mine of info and even if it is not a Quantum sail may be able to give you ideas or even recut if all else fails

He has produced a CD of kite flying tips, but I have yet to get hold of one as they were out of stock a month or so ago

Malcolm

[grantgoulding]

Hi Malcom
Thanks for the info.
We have the tack adjustable too but I am not sure if that would assist or not in this instance. I guess my fear is the sail is probably too big for the boat which is great in light airs but I was hoping to have the benefit of its size but to also lose some of the force when needed. I suspect having someone like Scott on baord would be the answer howver I didn't buy it from Quantum.
Grant

[Don Reaves]

One trick I learned with smaller boats is that when you are going downwind, when a gust hits, you should steer downwind to keep the hull under the sails. Then the tendency to round up will be minimized.

Now I must say that this advice applies to boats that can plane, which my JSO 35 will not do. So I don't really know if that's an appropriate tactic to apply here. Just thought I'd mention it, though.

Good luck with your spinnaker. I'm looking forward to getting one sometime in the not too distant future.

Don

[davideso37]

Grant,
Don is right about steering the hull under the sail. it applies both for rounding up and for rolling in to windward. If you let the boat start to round up it bring the apparent wind more on to the beam which makes the boat heel more and then into the broach. Here is how not to do it
There are two videos in the series. Keep your eye on the smaller yachts in the second video. I don't have any experience with the asymetric but would recommend trying to steer deeper in the gusts and ensuring that your mainsail out far enough for the conditions.
Regards

David

[krawall]

Hi,

we have a gennaker on our new So36i, it's 80sqm (860#).

We used it first time in better winds on the last weekend, wind was up to 15 true. We did have a similar problem although not as bad as you describe it. In one case when a bigger gust hit we would just let the sheet go and we'd heel a bit but were able to continue almost straight - weather helm was quite a bit, though. When talking of letting the sheet go I don't mean easing, I mean letting it out 2-3m or more at once depending. In the winds we had, we could not fly it more than 70 apparent and that was quite border line for me. We attained best speeds at 90-120 apparent (~135 true)

I think the point is that the main is far enough out. When looking at the videos, some mains were sheeted too hard that makes matters only worse. Although I know you can only go so far on a aft-swept-spreader rig which is a problem we all face.

I think usually if you have the main out enough and don't sheet the spinnaker too tight then it should be fairly self-limiting (ie after a bit of heeling and slight rounding up and a bit of easing sheet at the right time, load on sails would reduce by itself)

We also did not experiment too much with the tack line, but if it's too loose you may also get too full of a sail which I suspect would mean more heeling on higher than broad-reaching angles.

I guess it's the same as for us, we need to get out and try try try and experiment different scenarios.

Tom
SY Vega

PS: I also feel your sail is quite big for an asymmetric by looking at the sq ft.

[offshore]

Hi
I agree with the coments above and agree people often have the main too tightly sheeted. Another thing that might help is using a prodder like the selden one shown in the brochures. This will move the centre of effort further forward and give you less rounding up. The sail could also be recut to make it a bit flatter and therfore less powerful. Most silmakers will do this very cheaply with a new sail purchased from them.

Tom

We have been using regular kites on our 36i but were looking at a gennaker of a similar size to yours. Love to know what sort of numbers you get with it?

Barry
(Bad Habits 36i)

[krawall]

Hi Barry,

we're having a 180% J Gennaker, based on I=14.08 & J=4.02. I realize that because we use a bowsprit J is actually longer (and therefore the sail could be bigger)

We had reached 8.4 knots on around 120 degrees true wind angle at around 14 knots true wind speed. I could not carry over more than 150 degrees true, well I could but boat speed would simply drop into nothingness. 135 degrees seemed a good compromise in stability and speed.

I guess the max speed we can get out of this at this wind would be 8.8-9 knots but then someone must be real careful on the helm.

We're still learning.

Tom

[flightdeck]

Have to join in here, as there is nothing better than running well under spinnaker.
I too agree with the other's that over-sheeting is often the problem for round-up's under the conditions you talk about. While you are in "training" don't just set and forget, try to catch the broaching early on helm feel and by keeping the communication going from helm's person to trimmer, doesn't matter if the main does nothing, control the spinnaker and with time you can power the main up too.
It does take practice, but the rewards are tons of fun and joy.
On our last yacht, a Ross 780, we had great success racing and cruising with an asymmetrical, hit speeds of 12-13knots, top speed at 14.6knots on the GPS, so that will be the way we go for this SO32, not that we will see those speeds again.
We will go for an asymmetrical around 60sqm, something like Quantums V3, to be made by a local loft, we have just bought the Selden bowsprit, very easy to use and setup. Can't wait to get it all together, not much fun when the whole fleet leave's you behind, due to lack of a spinnaker.
Offshore, I should have the bowsprit on soon if you are interested in having a look at it. We are almost next to Rancha.

Cheers

[offshore]

Hi flightdeck

We are going out on Rancha for a full moon dinner sail on the 9th so I will have a look at your bowsprit then if its on. Other than that we will be sailing in the short handed series so we might see you out there.

Offshore

[grantgoulding]

We used the Spinnaker in the Round the Island race last month and managed to control the round ups using the advice from here. Certainly you can't just leave it alone but playing the sheet and getting the helm to alter course down wind has helped. We did however struggle to snuff it when winds speeds hit 20kts but that I guess that's to be expected!

[flightdeck]

well grantgoulding looks like you have moved your wind problem up the scale from 12-13knots to 20knots, great , practice, practice and keep racing that helps to
A: get out on the water,
B:want to sail as fast as you can,
C: need to get the spinnaker up.
Well done, hope you also had a good result from the race.

Offshore, not sure there will be much moon out on thursday due to rain, I have fitted the Selden bowsprit ring, but the sprit it self is below deck (can walk too easily) sing out and I can show you how it all looks and works, I'm happy with it so far. Measurements taken for the spinnaker, it's all happening....finally
Cheers

[tomatillo]

We sail our 43DS with an 85% flat cut spinny. We can sail it as close as the genny in medium air and then we really perform. Go down in puffs and have someone ready to blow the vang, which spills the main sail. Hang on!

[rhb]

Just ordered an SO42I but my experience with our last boat (a 38 ft racer/cruiser) was that just as important as easing the kite sheet was dynamiting the boom vang. When it was windy/gusty we'd have someone parked on the vang clutch ready to let it go at the first hint of a broach. This alone would often settle the boat and allow the helm to run off deeper to unload the boat and stop the broach. Dumping the vang opens and unloads the top of the main, eliminating one of the big forces involved in the round up. This works just as well with big wind and no spinnaker. The other thing we'd do was to get the crew all to the windward pushpit to help keep the rudder in the water and working.

Lastly, it's quite easy on many boats to stall the rudder by turning it too much while fighting a broach. We had to develop a technique of 'sawing' the rudder on and off to make sure it had bite and wasn't stalled.

Like i said - I can't speak with any authority about a Jeanneau 42 but much of what I've suggested should work on any sloop rigged boat.