Will a furled jib destroy the rig?

[zachduckworth]

Hi everyone,

Since buying my boat about 18 months ago I've been out a few times in fairly heavy wind, including gusts up to about gale speed. In fact just last week I had her out (Long Beach/San Pedro area) in winds up to about 35 kts. I was reefed to about 100% of my jay, then to 75%, and double reefed on my main. At one point I had the crew practice heaving too, which I try to practice whenever the wind starts to kick up (I am trying to learn skills for longer cruises).

I have always read that heaving to is the preferred tactic even in very heavy weather.

I then saw this video last night which got me wondering:

https://www.youtube.com/watch?v=U1SOra0GXrs

The presenter argues that a highly furled jib can result in a failed rig when the wind gets high enough. He also states that heaving to with a mostly-furled jib can result in rig failure. It got me thinking about ordering a storm jib asap. But is this really accurate in less-than-gales? He seems to be saying at one point that this danger is in much heavier weather, like 50kts or something. I'm very curious to hear about this because I do go out in a lot of iffy weather.

[GordMay]

Some[older] headsail control systems are designed to furl the sail [completely], without the capability to reef.
However, I suspect most modern headsail furling/reefing systems, that have a lower rope drum, grooved metal extrusions, and a ball bearing head swivel, are designed to furl, and to reef.

Do you know the make & model, of your headsail control system?

The goal of reefing is to produce a smaller sail, that is nearly flat, so that any excess wind is spilled off, and does not overpower the smaller sail. A slightly smaller, but, baggy sail, may actually be more powered, than an unfurled flat sail. However, the sail can simply be furled up [even more], making the exposed sail that much smaller.

An important feature, of a roller furling/reefing headsail, is having a foam or rope luff* [a tapered piece of material, sewn into the luff, that takes up the camber of sail, when it rolls around the headstay extrusion], ensuring that the sail still has a clean, flat [not baggy] shape, when it’s reefed down.
Modern sail shaping devices allow sailmakers to build sails that work in a range of conditions, from 5 to 40 knots. Beyond that, you’ll probably want to change sails.
Additional sail shape adjustments can be made by increasing, or decreasing, halyard tension, and by changing genoa lead car positions.
You can generally roll a headsail up to 30%, before it loses its effective flying shape.

* See also: “Reefing (furling) Genoa - efficiency?” ➥ https://www.cruisersforum.com/forums...ncy-90985.html

[barnab]

What exactly is the hypothesis you want to discuss?

[GordMay]

Originally Posted by barnab

What exactly is the hypothesis you want to discuss?

Originally Posted by zachduckworth

... The presenter argues that a highly furled jib can result in a failed rig when the wind gets high enough...

If the wind gets high enough, ANY rig can fail.

[Kettlewell]

Let's put it this way. A tightly furled jib is still a lot of windage up there and will put additional stress on the rig. I have observed my forestay oscillating a lot with a furled jib on it. On the approach of hurricanes I always remove the jib, and the reduction in windage is noticeable based on the pull on lines. After may big storms I have observed roller jibs that unfurled during the storm, resulting in tattered sails and sometimes dragging boats. However, my furled jib has stayed up in many ordinary gales without the rig failing.

[GordMay]

Originally Posted by Kettlewell

Let's put it this way. A tightly furled jib is still a lot of windage up there and will put additional stress on the rig. I have observed my forestay oscillating a lot with a furled jib on it. On the approach of hurricanes I always remove the jib, and the reduction in windage is noticeable based on the pull on lines. After may big storms I have observed roller jibs that unfurled during the storm, resulting in tattered sails and sometimes dragging boats. However, my furled jib has stayed up in many ordinary gales without the rig failing.

Indeed.
We damaged our furled genoa, then lost it [entirely] when we deployed it, trying to escape Governors’s Harbour, Eleuthra, during the 1993 ‘Storm of the Century’ [AKA: the ’93 Superstorm/Great Blizzard].
See ➥ https://www.cruisersforum.com/forums...3.html#post553

[Tin Tin]

We have been in 70 knot gusts with furled jib, rig did not fail on our cat. However as a back stop I do attach the 12mm dyneema spinnaker halyard to the fore beam when such weather threatens.

[zachduckworth]

Originally Posted by barnab

What exactly is the hypothesis you want to discuss?

Good question.
The specific question is whether it is dangerous to the rig to partially furl a roller furled jib in a storm to about the size of a storm jib, either for sailing or for heaving to. The video says that this can pose a great danger of destroying the entire rig, as opposed to using a storm jib, which has a different shape.

[barnab]

Partially furled sails tend to get a deeper profile, the contrary of what you want for sailing upwind in strong winds. Dedicated storm jibs tend to be cut with little profile and as you don't furl them the profile doesn't change.


Does the deeper profile do any bad when hove to? I don't think so, but lack the practical experience.
Does the deeper profile do any bad when sailing downwind? No.
The only time when the deep profile is really bad is for sailing upwind.


The biggest danger I see in partially furled sails is they might unfurl, which is for sure very "unpleasant".


How it can destroy a rig I don't really see, I generates a force and that force will make you heel. The boat is designed for that.



I noticed flogging being mentioned, flogging is for sure not good for the rig but if it can take one down I have to leave to others...But here I would say that flogging simply happens when you sail closer to the wind that the sail is / can be trimmed for. And then it doesn't matter if it's a furled jib or storm jib. You simply can point higher with the flatter cut storm jib.

[Breaking Waves]

Originally Posted by zachduckworth

I have always read that heaving to is the preferred tactic even in very heavy weather.

Not really, highly depends on the boat and the situation. many modern boats don't heave too in all that stable attitude in big waves.
Our last boat most definitely did not prefer heaving to. Much preferred either forereaching or running with drogue. Our pervious boat did like heave-too, but was a ketch and did it in quite a different/better way than sloops.

The presenter argues that a highly furled jib can result in a failed rig when the wind gets high enough. He also states that heaving to with a mostly-furled jib can result in rig failure.

Not really. If you allow the jib to vibrate a lot, or simply have too much sail up for the wind, you can ofc in some situations bring the ring down. But with modern sails and modern furlers with the sail properly sheeted, it is really unlikely to cause a problem.

and as an FYI . . . I have sailed twice around the world, including in the southern ocean, ofc including quite a bit of heavy weather.

[/QUOTE]

[TrentePieds]

Zach, you said: "The presenter argues that a highly furled jib can result in a failed rig when the wind gets high enough...."

Well, of course! AS Gord May sez so rightly: "any rig can fail when then wind gets high enuff."

Since you are a fairly new sailor, perhaps you'd like to step back a moment and consider the basics. There are two concerns that you should keep before you as the wind pipes up: 1) The HEEL of the boat, and 2) The BALANCE of the boat.

You keep the HEEL of the boat within reason, say between `12º and 18º, by reducing the TOTAL area of canvas you are wearing. Your clinometer will tell you your degree of heel. You don't need fancy electronics for that! Reducing canvas to control heeling is called "REEFING", NOT "furling", and if we keep the "sailor speak" straight, we will understand each other better :-)

You control the BALANCE of the boat and keep it where it needs to be by APPORTIONING the TOTAL area of canvas between the Headsail (not the "jib", a jib is a particular kind of sail) and the mainsl.

Get those two things right, and a little five-tonner like your boat (and like TrentePieds) will NOT lose or even damage her standing rig in any wind you can handle :-).

There is fairly simple mathematics that will tell you (while you are comfortably having a drink in you livingroom) how much TOTAL area of sail you should carry in any given wind velocity, and you can even go so far as to make up a chart to put up at you Nav Station. The input parameters for those calculations should be readily available for your boat.

You can even determine the RELATIVE sail areas required for a balanced boat by the simple means of drawing a profile of the boat (c/w given, chosen sails) on Bristol board, and then, by a simple experiment, finding the centre of gravity of that Bristol board profile.

Doing those simple things will teach you far more than watching somebody bloviating in a 15 minute "clip" of what HE does on HIS boat. His boat ain't the dame as yours :-)!

There is nothing wrong with what the Norwegian chappie sez in the clip. It is just something that isn't particularly USEFUL for you. As your post demonstrates. All it did was confuse you :-) That I attribute in part to the chappie not being a good teacher.

Bonne chance :-)!

Or to put is in Norwegian so the chappie will understand it: "Held og lykke" :-)!

TrentePieds

_

[Greatest Lakes]

I agree. Gord is correct. Having a furler that takes some of the load using a halyard, rather than the furlers with the internal halyards also reduces stress on the rig.

[Adelie]

I would install a inner forestay that goes 2/3-3/4 way up the mast and attaches to the foredeck with a J-hook so the bottom end can be removed or replaced at will. From that I could fly a small jib (75% blade) and/or a storm jib.
You would want running backstays both side.

All this rigging would cost some but it would also provide redundant support for the mast.

If you had a hard vang with no topping lift then you could have the running backs lead to the quarters of the hull and once the main was reefed far enough you wouldn’t need to swap them in tacks and gybes.

[Benz]

As the jib is furled smaller and smaller, the load on the forestay is placed along less of its length, and further from the ends. So the load gets concentrated on the middle of the foil--I'm no engineer, but I don't think that's ideal A storm jib, unless on a long pennant, will keep the load lower down, putting less of a deflecting force on the forestay.

My biggest cringe with a furled headsail in big winds is how the sail gets squeezed and abused where it's rolled. Even with a foam luff pad, it's not gentle on the material.

[catsketcher]

My two cents

A fully furled jib cannot hurt the rig, and if the jib is kept partially furled then all is okay. I have seen some pretty awful rig oscillations on a rig that got loose in a nasty gale. I rang the owners of a nearby boat when their headsail unfurled slightly up top, then it started pulling more and more head out of the furl until it was flogging.

The owners sent their 20 year old son down and together we went out on their dinghy to try and tame the furled sail. Getting out to the boat was hard enough and getting on was fun. On the boat the rig was pumping like mad. Rigs are designed for mostly sustained loads but the cupped head was filling and collapsing and causing the mast to wobble a fair bit. I don't know if it could cause a resonance in tune with the rig's own natural period, but if it could then I reckon the rig would be in serious trouble in enough breeze.

I always furl my genoa pretty firm, and drop it in a blow, or if it is just a short blow, winding the kite halyard around it (especially up high) is a good idea.

Consider a staysail - I love mine and am thinking of getting an even bigger one for days like a fresh sea breeze. The boat balances much better and you protect your expensive large genny. I have had my staysail for decades and it is still in great conditon, because it is heavy and kept out of the Sun.

cheers

Phil