Jackline tension

[Pete7]

Originally Posted by RDW

I have the jack lines that most say not to have but they seem to work well in my case. I have stainless cable that runs from the bow to the stern along the deck.

Now everywhere I read it says do not use round jacklines. Have I been fooled? rdw

RDW, ours are stainless steel (about 5mm) wire too and will be replaced with stainless steel wire sometime this year. We replaced the standing rigging in January which focussed my mind on the remaining stanchion wires and jacklines. They are probably original and at 22 years old, time for replacement, which oddly enough no one ever seems to discuss, standing rigging yes, but not the other bits.

I know they can roll under foot but with good deck shoes or sailing wellies it never seems to be a problem.

Pete

[capngeo]

So fire up the flame machine, but I just use a length of double braid long enough to connect from the center of the boat to each end. Yeah if I go over, I'll get wet, but I can haul myself hand over hand to the deck if need be (don't ask how I know I can do this)

[nautical62]

I'm sure my view will be unpopular with many here:

For going solo I prefer a single, fairly long tether. Up front, (small cruiser) the distance from the center of the boat to the edge may only be 2 feet. Allowing for a little slack and stretch, even a 1.5 foot tether attached to a jackline would probably put me over the side and a tether this short would also severely limit what I can reach. If I went over attached to a short jackline tether, I'm sure I'd immediately get washed back behind the next stanction, hanging half way overboard. I feel having my fall broken after falling, but before hitting the water completely is prone to injury and I can't imagine I'd ever get back onboard from that position.

My preference would be to hit the water, and find myself being dragged behind the boat. I feel fairly confident from my white water rescue days that I could roll over and drag my way up an 11 mm line to the back of the boat, where I have a walk out transom that I have boarded many times from the water without the ladder down. Someday, I'd like to try that under controlled circumstances.

With several crew on board, I'm sure long tethers would get hopelessly tangled around each other and the boat would be wider, but that's not true going solo on a smaller boat. Also note that using a long tether does not mean I can't clip myself with a short tether to an alternative attachment point when appropriate to take care of a problem, such as around the mast if dealing with the mainsail, a point in the cockpit, etc.

This feeling I should note is based on night gulf stream crossings, crossings between islands, etc, not passage making conditions.

[Loco Gato]

I use flat webbing down the starb'd and port sides beginning at the pulpit and ending at a pad eye one on the aft cabin dog house( center cockpit). At the bow I take apart ratcheting tie down straps and run the jack line through them and pull hard! when they loosen up then I just ratchet them tight again. Lays flat along the cabin sides and has never been an issue.

[LakeSuperior]

Originally Posted by nautical62

My preference would be to hit the water, and find myself being dragged behind the boat. I feel fairly confident from my white water rescue days that I could roll over and drag my way up an 11 mm line to the back of the boat, where I have a walk out transom that I have boarded many times from the water without the ladder down. Someday, I'd like to try that under controlled circumstances.

Not unpopular but just unrealistic. With weather gear">foul weather gear and clothing on underneath, traveling at 5 knots, with a sea, you would have to be an exceptional athelete to drag yourself up to the transom.

I have many years of experience dragging behind the boat with my children. With a swimmiing suit on. Once you are up to 3 to 4 knots the going gets tough. Can't picture it doing with full gear on.

[nautical62]

Originally Posted by LakeSuperior

Not unpopular but just unrealistic. With foul weather gear and clothing on underneath, traveling at 5 knots, with a sea, you would have to be an exceptional athelete to drag yourself up to the transom.

...

Perhaps the lesson there is that not all situations are the same and different situations will lend themselves to different solutions.

Pulling against 5 knots of current to the stern may be difficult, but for me attempting to haul my way over the side rail would be even worse. (As I said in my earlier post, if I'm at the bow on my boat, I don't think it's possible to have a tether short enough to prevent me from going over the side)

As I said, it's something I'd like to test some day under controlled circumstances. Until one has actually tried it, it's just conjecture.

[estarzinger]

Originally Posted by SvenG

In the tether thread there are comments to the effect that your tether should not let you go over the side. . . . setting things up to prevent anyone going over the side in the first place would still be really desirable if it is at all practical.

Most people who go over the side were working on something, not just moving up the deck, so the most important and practical thing is to have specific clip in points (eg pad eyes or tangs) at the major 'work stations' (eg steering, winches, mast, innerstay, bow) and when you are sitting/working at those points clip in with a short tether (short enough you can not get to the edge of the boat). That will keep you on board 99% of the time - if you actually use them. Some race boats have tethers permanently splices to these hard points so you don't forget to bring your tether.

These hard points were added to the ORC requirements because it was realized that #1 the MOB's were mostly when people were working with both hands and not holding on, rather than when moving up the deck, and #2 because it was realized that it was very hard, almost impossible, to design a practical jackline system that would keep you on the boat while moving up the side deck.

As far as moving up the side deck - proper procedure is more important than the jackline - using a proper stance (low cg, crawling if necessary in the worst conditions), watching your footing, always having one hand with a firm grip on the boat (handgrip or stay, etc) are the keys.

Generally I like to go up the windward (high) deck. The high probability if you are pitched is you will go down to the low side and a short tether and moderately tight jackline should keep you on the boat. But it is possible to be pitched the other way and a short tether/moderately tight jackline along the cabin trunk will probably not keep you on the boat - especially near the bow or stern where the jack line attachment points tend to be close to the deck edge. The key is to realize the jackline is NOT a foolproof way to keep you on the boat when moving up the deck and to be sure you always have 'one hand for yourself'.

Some of the Canadian and UK life/rescue boats have an interesting system - instead on jacklines they have a hard track with sliding/ratcheting cars (like a mainsail track/car system) that are mounted along the top of the cabin trunk. You clip onto these cars - when moving forward the will slide forward but if you fall the ratchet will stop them from sliding back (you open the ratchet when going back). This approach obviously eliminates any stretch in the jackline and avoids the shock load geometry problem that a tight jackline creates. I have never seen it done on a cruising boat.

[Dockhead]

Originally Posted by savoir

And the evidence in support is . . . . . .

Simple mathematics. As Ersatzinger posted above, a 5% deflection is about a 10x multiplication of force. Tighter = more, and it goes up geometrically.

[goboatingnow]

I have seem the hard track based lifeline on one custom Dutch boat. Very good it was too.

Dave

[SaucySailoress]

Originally Posted by RDW

. FYI, I am inexperienced. The boat is a 46 Morris that I bought in 2008.
Now everywhere I read it says do not use round jacklines. Have I been fooled?

We have some webbing jacklines - but I've no idea where they are now, must look 'em out before that storm hits...

On our last boat - the one we had to rebuild from scratch, when that storm hit we used spare rope that we had leftover from the rebuild. It worked - none of us went over! And since it was a pretty big storm (30 ft swell, no less), we were moving around so carefully that nobody once slipped on them. They could have been made from banana skins and we wouldn't have slipped on 'em (might not have held us in so tight, tho).

Now I think of it, we've got tons of ropes on the boat - we're kinda used to avoiding them... So I think shape doesn't matter so much.

[Bruce Bevan]

I have done a lot of high tower work where some of the important concepts are that you are always connected to the tower, the harness won't let you fall out of it and if you fall you will be facing the tower so you can regain your hand-hold. I think the same principles would apply when on a boat.

The harness would have the anchor point for the safety line attached to the chest area. This would help in getting back onboard. The safety line would be a dual system that has double locking safety hooks, on each strap, that can opened with one hand. The ones we used cost about $10.00, had a four inch wide mouth and were tested and approved. I think they were called steel workers safety hooks. Worked great. Heavy though. The body harness would have loops that go around the upper torso and legs to stop you slipping out when being dragged in the water. Our harnesses were industrial weight but what was most useful were waist rings on each hip that allowed for supplemental hooks on short straps that were hooked in when you had to work on something.

I found that using different lengths of webbing loops allowed for adaption to different situations. This might be an option to have permanenty on sections of jackline that needed a longer tether. Such as near the bow.

If you can predict where you will be hanging if you do happen to fall over then dragging some rope assist to get you back on board at those points might pay off one day.

BB

[philocat]

On Marika, our last boat we had a single removable jackline.

Attached near the bow run down the side, around a winch and across the cockpit and back again to the bow. With this you could clip on from INSIDE the companionway and move about almost anywhere around the deck without having to unclip. One shackle to install. It was only installed for rough weather or o'nite sailing. It was 1/2 inch nylon but uv resistance was unnecessary.

Regarded this only as last resort - so being half drowned over the side and maybe not getting back in for a while is still preferable to being fully drown unattached to the boat.

I hear the arguments about round rope -but this is but one other rope on the foredeck -eg. jib sheets

[thinwater]

Originally Posted by estarzinger

The practical advice from the British testing was to tighten up your life lines to a bit tighter than you normally do, find the strongest guy in the boat yard and have him pull up on the middle of the life lines as strongly as he can, and then inspect everything. If there is nothing broken or damaged you are ok, but if there is something stressed you needed to fix/strengthen it in any case.

I did exactly this on someone's boat ~ 5 years ago, with the same calculations in my head. I'm not a big guy, 160 pounds, but I did pull one of the pad eyes out of the deck. The owner wanted very much to be mad at me, but I asked him first and he swore it would hold easily. The lifelines were 5,000 pound rated and fitting had a small backer (fender washers), but the deck was cored. However, a number of fittings were badly distorted, indicating if the deck had held a shackle or swage would have failed.

The issue was on my mind that day because of a similar failure in a construction site I investigated; the rigging was sound, but with no shock attenuation, a very short fall (4 feet) caused enormous forces.



Stainless jacklines have another advantage; they can be kept rigged 24/7. While some like jacklines they can take on and off, to be rigged when needed, for me needed is...
* when I sail alone, with green crew, or on watch alone
* at night
* when the water is cold, like now
* when the wind is up
* off-shore
* or when doing some bit of work very near the rail or standing on the sugar scoops (like landing a fish)...
which means nearly every day.

I have a catamaran, so I will not speak to location; it's simple with wide decks. I do believe that for cruisers a permanent jackline arrangement is as important as PFDs and seat belts, and more important than sails or running rigging. It's not optional or "occasional." I would sooner leave the PFDs at the dock. How do I know when I will need a jack line right now?

[smurphny]

Have even heard of people stringing a line from bow to stern on each side so that it's reachable from in the water...but geez...how many lines can you have hangin about before you wind up caught in your own contraption!