Inadequate Design of Furling Systems

[Spirit (of Glenans)]

I believe Reef Rite produce(d) a reefing system with standard rope on drum and a locking pin operated by a long wire back to cockpit. Plenty of these in NZ.
The initial problem appears to be people based rather than the equipment though?

The Reef Rite appears to have the solution to the 'fail safe' question.
Initial problem definitely people based but the above removes the human element and improves vastly the safety factor.

 

[Spirit (of Glenans)]

So my guess is that the OP (not skipper he says) was reaching across the F7/8 westerlies heading south in open sea; fairly safe with everything reefed to the full. Suddenly the reefing line gives way and a large jib/genoa unravels unbalancing everything and driving the bow round before the wind. A jibe follows and breaks the mainsheet (its windy out there), another violent jibe as control is lost. Hopefully someone is getting the engine on and establishing some sense of order, head to wind; hopefully it's not dark too. Hopefully there aren't lengths of mainsheet nor furling line in the water ready to foul the prop.

A scary scenario which would test any of us. I can understand why the OP is questioning the way the furling works. That 8mm furling line could dis-mast the boat in those circumstances. Our old Harken had corresponding holes in the drum and the drum casing that could admit a short line or a drop nose pin to lock the furler - crude but reassuring. Our new Selden (not as good in my opinion) doesn't offer anything the same, but a short line tied from the tack shackle to the pulpit provides a bit of security. I think the manufacturers should think about this and offer something similar.

Of course once the furler is locked off, someone may need to go forward to unlock it in less-than-ideal conditions; but choosing your moment to brave the foredeck with a tether is altogether preferable to a sudden and uncontrollable deployment in a gale of a sail that might be almost the size of a full mainsail on a mast-head boat!

You have captured the situation very well, Garvellachs. I forgot to mention that we did'nt find out until daylight that the second gybe actually cracked the boom.

 

[pagoda]

You have captured the situation very well, Garvellachs. I forgot to mention that we did'nt find out until daylight that the second gybe actually cracked the boom.

Many years ago our boat of that day was being raced in West Highland week, by son and friends. All experienced sailors , though gung-ho on my scale...
They bailed out with a broken boom. Cracked and split where the kicker fitting attached. They said it was just an ordinary gybe. I kind of doubted that , but the weakness was corrosion on the inside of the boom - well out of sight. I think any hard gybes on older booms need close investigation afterwards. Our furler in that boat was almost first generation Harken gear. Not that stylish but gave no problems other than requiring some new foil connector screws occasionally.
In a loosely similar vein to the O/P, we were sailing with our Code0 a couple of months ago in Loch Fyne . Steady 10-13Kts, almost broad reach doing 8-9Kts. That was quite workable. We got a couple of unwanted gusts and decided to furl it away. The furler uses a continuous line. The second gust had damaged some of the stitching of the tack/sail fitting. Starting to furl the remaining stitches burst and we had a full sail (80m2) with a loose tack and no way of furling it. 15 Plus Kts now .That resulted in two of us having to go up to the bow and drop the sail like an asymmetric . That was exciting enough as I had to wade up the leeward side of a submerged toe rail. We got it down OK and stuffed in a bag. Some of the issue was down to lack of experience of the helm at the time. Not much time spent sailing with asymmetric sails. It doesn't take very much to go from normal to nightmare experience. The O/P was pretty lucky to get away with not much more than a fright. (equipment damage notwithstanding)

 

[lpdsn]

They bailed out with a broken boom. Cracked and split where the kicker fitting attached. They said it was just an ordinary gybe. I kind of doubted that...

I did a Gordon just a few miles into the delivery following a race we'd just completed. I didn't break the entire boom (so maybe not a full Gordon) but the kicker fitting shattered. It wasn't a gybe, we were just reaching and it was the first time it had been suitable to ease the sheet whilst keeping the leech reasonably tight, so it was the first time the kicker had been on reasonably hard. Throughout the race it had been mainly windward work in heavy airs or light airs with twist in the main and the mainsheet taking most of the load. If at any stage I'd needed to put a lot of kicker tension on it would've gone. It turned out to be due to a bolt through the carbon lugs being overtightened.

 

[dunedin]

Perhaps the fail safe methodology is to unroll fully, that way the sail can be taken down if the furling mechanism fails.

That works fine on small boats and/or ones with large crews. But many people sail singlehanded or with just a couple on board.
When a large genoa suddenly unfurls fully in 30-40 knots of wind on a boat bigger than about 35 foot, it can be almost impossible for one typical person to tame the sail easily let alone drop it and get on board. It is difficult enough in a marina or on a mooring, removing a flogging sail in a gale. On a foredeck bouncing around with the boat having lost control, and potentially the boat being driven onto a lee shore, perhaps in the dark, it is a very dangerous situation.
Hence the near fatal accident I referred to, which was just one example.

And clearly lots of sails get lost each season with furlers unfurling on boats left unattended.
A better fail safe system would be very worthwhile .....

 

[dunedin]

And from this link it does look like at least the New Zealander’s have looked at this and thought that better design could be applied ......

http://reefrite.co.nz/marine/head-sail-furler/head-sail-furler-details/

This headsail furler has a locking pawl and some other interesting innovations.

Does look better than other current designs in quite a number of ways.
But in this respect having a locking pawl, just like a winch, to improve sail salt when reefed does seem like a very sensible and simple improvement. After all many boats use halyard locks to maintain tension, why not on jib furlers.

 

[dom]

Does look better than other current designs in quite a number of ways. But in this respect having a locking pawl, just like a winch, to improve sail salt when reefed does seem like a very sensible and simple improvement. After all many boats use halyard locks to maintain tension, why not on jib furlers.

The NZ kit seems well made, sensibly thought out and it's no more expensive than quality mainstream furling equipment. Perhaps a reason for its low penetration is that lots of other things can go wrong with the furler: top-swivel jam, halyard wrap, drum bearing collapse, bust foil, etc.? As for dropping the jib in a blow I get that, but if engine is working and the boat can be held at say 15 degrees off the wind, even with a biggish sail it's often a fairly quick drop if the boat has a crew member experienced in foredeck work. Can require techniques like double tethering if really rough. .

 

[Kukri]

Harken no longer include the locking pin: their Mark IV furlers don’t have it.

Giant leap backwards, imho.

 

[Deleted member 36384]

That works fine on small boats and/or ones with large crews. But many people sail singlehanded or with just a couple on board.
When a large genoa suddenly unfurls fully in 30-40 knots of wind on a boat bigger than about 35 foot, it can be almost impossible for one typical person to tame the sail easily let alone drop it and get on board. It is difficult enough in a marina or on a mooring, removing a flogging sail in a gale. On a foredeck bouncing around with the boat having lost control, and potentially the boat being driven onto a lee shore, perhaps in the dark, it is a very dangerous situation.
Hence the near fatal accident I referred to, which was just one example.

And clearly lots of sails get lost each season with furlers unfurling on boats left unattended.
A better fail safe system would be very worthwhile .....

What are you going to do if the failsafe doesn't allow you to furl. You still need a plan to manage that situation, single handed or not. The risks you mention are equally valid in this case.

 

[lw395]

The NZ kit seems well made, sensibly thought out and it's no more expensive than quality mainstream furling equipment. Perhaps a reason for its low penetration is that lots of other things can go wrong with the furler: top-swivel jam, halyard wrap, drum bearing collapse, bust foil, etc.? As for dropping the jib in a blow I get that, but if engine is working and the boat can be held at say 15 degrees off the wind, even with a biggish sail it's often a fairly quick drop if the boat has a crew member experienced in foredeck work. Can require techniques like double tethering if really rough. .

The top swivel looks heavy.
The foil connector blocks appear to be ali bearing directly on the s/s wire.
How reliable is the latch reeally going to be after ten years afloat?
Does it have a tack swivel like the Harken?
Not sure about the sealed bearings, I've had to change enough 'sealed' motorbike wheel bearings.

Maybe it's better to address the fundamentals of using big sails in a lot of weather?

 

[Kukri]

I’m still going with Harken, for those reasons, but I did like the idea of the locking pin.

On a mooring or in a marina berth, one can do what my father, the source of the “sailmaker’s friend” quotation, taught me to do with a Wykeham Martin furler fifty years ago, which is exactly what Harken UK have told me to do in an email this morning - take a couple of extra turns of the sheets when rolling up and put a tyer round the sail at the clew when fully rolled.

“It is a common practice to ‘over-roll’ the headsail so that there are a couple of wraps of the headsail sheets around the furled sail preventing the clew from being loose and able to catch wind and begin to unroll the sail. Another solution could be to put a sail tie around the furled sail if it is to be left for long periods of time. It would be no safer to have to send someone up to the bow to put a locking pin in place than to apply the sail tie in heavy weather so this could also be a solution in that situation also.”

Well, not with the sail part rolled, which is just when a failure is most likely and most serious.

This assumes that you can reach the clew, and iirc Calder advises against taking extra turns. And I think it is a d... sight riskier to stand up and reach over your head at the bow in heavy weather than it is to crawl forward, double tethered, and put a pin in, whilst kneeling.

Something tells me that Harken have had an attack of accountancy, or that a New Broom has announced “you don’t need that bit...”

I don’t agree. It would be so easy to put this right... it’s just better in every way to leave the system with no load on the line.

 

[lw395]

The last thing you want is 'no load on the line'.
This is the only way I've ever managed to have aproblem with a Harken furler. On a long rolly passage downwind, the loose turns on the drum dropped down into a nightmare of clove hitches as the drum moved around.

I agree, the lack of a hole to lock the drum is an omission, IMHO. But the drum is 'only' plastic. It's not really designed to take the force of a big sail half loose in a gale.

You can get around this, for instance lash the tack swivel to the bow cleat, anchor roller or whatever, but, with a Harken system (at least ours!?) the tack swivel is free to rotate relative to the headfoil, such that the headfoil rolls the sail from the middle of the luff rather than the tack.
So, some fairly ugly things would happen to the sail perhaps?
But on a properly installed and maintained system, the furler line should never chafe through. Our Harken gear has shown no signs of wear on the line.
Maybe we should all just check this and thank the OP for bringing it to our attention.

There are plenty of single point failure bits of string on the average yacht which would be equally awkward. Do you have a locking mechanism on your gooseneck in case the mainsheet chafes through?

 

[Kukri]

Very fair points; thanks. Yes, tack swivel still like that.

I notice that Harken supply the line as part of the installation.

I did once lose a mainsheet, very early in my sailing career. It’s a remarkably awkward thing to have to deal with, especially when single handed. I learned not to let it happen again!

 

[lw395]

I broke a mainsheet on a dinghy once. One of those boats with a hoop for the main, not protected from sunlight by the cover. I capsized and nearly got run down by the boat behind.

 

[Spirit (of Glenans)]

What are you going to do if the failsafe doesn't allow you to furl. You still need a plan to manage that situation, single handed or not. The risks you mention are equally valid in this case.

Hand the sail?

 

[Deleted member 36384]

Hand the sail?

My plan for a sail that can not be furled would be to drop it if fully deployed, which I have done in a F6, on a heaving foredeck. If not fully deployed, but jammed i.e. it can not be lowered, I have wrapped a furling genoa with the spinnaker halyard, surprisingly effective. The sail does not have to be flogging but it needs to be luffing significantly to get it snuffed enough to release the sheets further.

 

[yerffoeg]

When partially furled, our previous genoa often managed to unfurl itself in strong winds. When I ordered a new genoa last year the sailmaker suggested putting a foam insert in the luff. This has solved the problem, presumably by creating greater friction between the rolls of sail.

 

[pvb]

When partially furled, our previous genoa often managed to unfurl itself in strong winds. When I ordered a new genoa last year the sailmaker suggested putting a foam insert in the luff. This has solved the problem, presumably by creating greater friction between the rolls of sail.

I'm confused by this. Surely it could only "unfurl itself" if the furling line was released?

 

[dunedin]

When partially furled, our previous genoa often managed to unfurl itself in strong winds. When I ordered a new genoa last year the sailmaker suggested putting a foam insert in the luff. This has solved the problem, presumably by creating greater friction between the rolls of sail.

No, the foam luff makes the sail roll up neater (compensating for the extra width of sailcloth at the edges), which avoids the baggy sail shape when reefed.
If the sail is rolled up tightly, and the furling rope doesn’t slip or break, the sail should not unfurl, irrespective of the foam luff.

 

[dialdan]

I have just fitted ahttp://www.almasts.com.au/furling-systems/Reefit from Almasts, very happy with it