Asymmetrical Spinnaker Wind Speed Rating

[Tmacmi]

We inherited an Asymmetrical Spinnaker with the boat.

Short of taking it to a sail maker, is there a way to figure out how high a wind speed I can use it without risk of damage?

[TheOffice]

Do you know the weight? It should be marked as .5, .75 or 1.5 ounce

[JPA Cate]

Yes, in a way. If it is .5 oz, that is the lightest weight, and they are pretty fragile. .75 oz is what most spinnakers are made of, you can fly it in heavier air. The 1.5 oz is the weight of cloth we had on an old race boat, for it's "storm chute", and it was good up to 25 kn., but remember, it is off the wind.

It's probably 3/4 oz., and probably you'll be wanting to take it down earlier than you have to, with a new to you boat, and getting to learn how it behaves. Spinnakers can be God's way of ruining an otherwise beautiful afternoon for folks who are not used to them, and sometimes, folks who are used to them.

Ann

[Calif.Ted]

Probably about 15 kts.

[Tillsbury]

I took my asymmetric to the local sailmaker and got him to take the panels out to have it on a top-down furler. Make all the difference single handing, best thing I ever did you the boat.

[chrisr]

the max windspeed for a kite will depend on the AWA. the deeper you run, the higher AWS you can stand. on the raceboats we'd often carry a 0.5oz kite in 20kts AWS if running deep (160-170 AWA), whereas we'd go to 0.75oz at say 12kts if tight

also depends on sea state / gust conditions / trimmer...kites hate shock loads, but can take higher windspeed if nice and stable

anyway, a typical 0.75oz A-sail will be pretty indestructible and be able to cope with almost anything you are likely to put it up in

cheers,

[Pete7]

Originally Posted by Calif.Ted

Probably about 15 kts.

We sail conservatively, its down at the first hint of a gust approaching 15 knots.

It's a big sail and provides a lot of drive in 10 knots, I don't want to loose control with a sudden gust perhaps from a headland or risk damage to the sail which I think is 0.75oz.

Pete

[Tmacmi]

Thanks for the feedback all! Unfortunately there isn’t a label on sail to show cloth weight. I”m going to guess it’s a pretty standard weight.

Point taken about taking an unknown sail on a new to me boat to its limits.

[Pete7]

If you have a friendly sailmaker nearby, they ought to be able to tell you the weight and perhaps they give it a quick once over. However, needs to be now, not in the Spring when the world goes mad and everyone wants their sails now. Ours went in for a clean a month ago, again whilst its quiet.

Take a nice chocolate cake in as a thank you for their advice and offer it upfront, you might get away without an invoice and some really good advice in return.

Pete

[Tmacmi]

Originally Posted by Pete7

If you have a friendly sailmaker nearby, they ought to be able to tell you the weight and perhaps they give it a quick once over. However, needs to be now, not in the Spring when the world goes mad and everyone wants their sails now. Ours went in for a clean a month ago, again whilst its quiet.

Take a nice chocolate cake in as a thank you for their advice and offer it upfront, you might get away without an invoice and some really good advice in return.

Pete

I’ll give our sailmaker a huge shout out: North Sails Detroit.

I took all our “new to us” sail in for inspection and touch ups. They were very knowledgeable and generous with their time (in December). I had them mark the roller head sail with various reef points with tell tails.

Unfortunately I forgot to ask about the spinnaker weight.

I’ll through the bag in the car and stop by to see what they can tell me.

[captmikem]

Half ounce is pretty light. I used to carry two chutes, half and 3/4. They were symmetrical so never used them closer than a broad reach. I rarely used the half ounce chute, maybe half a dozen times in very light wind (12 kts or so). I would normally douse my chutes around 20 kts. Thru thousands of miles I have only blown them (twice) by getting them in the water (Gusts over 30kts ending in broaches). I pulled the head out of one but it was poorly constructed.

That said I notice many people who fly asymmetrical chutes tend to over sheet them as they are pretty much useless on a run and folks reach try to close reach with them. That puts a lot of stress on a chute.

I would throw it up and sail with it, you can tell when it is straining, if you are in 16 kts or less you will not be putting much stress on it until the wind gets to the beam and fwd of it.

Feel of the cloth, if it feels like a silk sheet it is pretty worn and will have less strength. If it feels crispy and crinkly it is probably pretty new and in good shape.

remember, if you are broad reaching and running in 18kts the chute is only seeing 12 or less.

M

[sailon46]

I always put mine back in the sock when I see 27 knt wind.
Ernie on the Mary Jane

[mholtzberg]

My friend has a Hunter 340 with a cruising chute with a dousing sock and we broached hard with the boat when she rolled and the owner had the main prevented... Imagine a 34 foot cruiser on it's side sliding sideways through the water... I had my daughter at the spinnaker winch which she blew the sheet and didn't have gloves on OUCH.. I was mid deck trying to untie the douse and pull it down which I managed to do and then I had to cut the preventer which was the tail of the lazy jacks and I was on the other side of the shroud... OUCH... That shroud popped me in the chest.. Although the boom is normally 6-7 feet above the water, when it crossed over the boom tip hit the water before the boat came back up. The owner was at the helm and started the motor to try and get some momentum and the spin sheet got sucked under and snapped the motor mounts. Additionally, I asked my daughter to come up and hold the dousing sock down while I tried to get the main released and bc of her hands being torn up she released it and we broached again.

Once all the sails were unloaded we wound up dumping the spin down the main cabin hatch instead of the v-berth hatch.

The lazy jack cleat on the boom was half bent on half yanked out of the boom..

I think we broached because we were exceeding theoretical hull speed ~7.2knots and the GPS said we were doing 8 knots.

All in 20Knots of breeze.

A Hunter 340 has a 3/4 rig and a displacement weight of about 16,000#, and to say the least the owner's wife has banned the chute from the boat.

In the end as the wind increases the loads increases so keep in mind what needs to release if all hell breaks loose and things go wrong.

[captmikem]

Originally Posted by mholtzberg

My friend has a Hunter 340 with a cruising chute with a dousing sock and we broached hard with the boat

Etc.

In the end as the wind increases the loads increases so keep in mind what needs to release if all hell breaks loose and things go wrong.

That is exactly why you need to blow the guy. Blow the guy and the chut streams out harmlessly ahead with no load on the boat. Even a cruising (asymmetrical) chute, a simple sparcraft shackle with a line thru the trip hole, a quick yank on that line and everything is calm again. You can even lead it back to the cockpit if you so desire.

Make it easy, rig a way to blow the guy, then sock it.

M

[Pete7]

Originally Posted by captmikem

That is exactly why you need to blow the guy. Blow the guy and the chut streams out harmlessly ahead with no load on the boat. Even a cruising (asymmetrical) chute, a simple sparcraft shackle with a line thru the trip hole, a quick yank on that line and everything is calm again. You can even lead it back to the cockpit if you so desire.

Make it easy, rig a way to blow the guy, then sock it. M

You have confused me, why is there a guy on an asymmetrical spinnaker?

I have always just blown the tack then lowered the sock before dropping it.

Pete