Jacklines (vs jack's line)

[JohnV]

Brion, your point addresses my original question of one long line vs 2 short ones: which is more likely to fail when a weak point is stressed beyond its limit?

Here’s been my thinking—if you can bear with me:

One long line involves 3 hardware attachment points and 2 splices (given a round turn at the anchor bit).
Two short lines: same 3 hardware points plus 4 splices.
If those are the weak points, then one long jackline wins 7 to 5.

But, with a long line, unseen fatal damage somewhere along the rope—let’s say it's on the port side—can break whichever side you fell against. With 2 separate jacklines, you can fall safely on the starboard side of the boat, so your first fall has 50/50 odds. Fall twice though, it’s 3-to-1 you’ll break the rope. (2 falls can be P & P, P & S, S & P or S & S). Fall more than once or twice, or add more chafed spots, and you’re a goner with either jackline arrangement. (Might as well jump overboard before you break something.)

Intuitively, between the structural weak points and random chafe point(s), one long line seems less vulnerable to me. But that’s all hypothetical, and real-world experience with the issue carries a lot more weight. What do you think of my reasoning?

My thanks to all who have weighed in so far.
John V.

[Dave Mauney]

I like Brions idea of chest high life lines. I wonder where and how you would attach them to keep them that high. I am also confused on the word "outside". I thought the idea was to pull you toward the center of the boat. Thanks

Goodwinds
DaveM

[Ian McColgin]

Different lifeline arrangements mean different tethers. Most people preferr to go forward along the weather rail.

On a two or more masted boat where the jackline can be strung held up at the shrouds (you'll want the final anchor at a chainplate way further aft or forward) this can give you a nice long run and a handy support to hang on to.

I tried it on Goblin, an Alden 43' schooner, but didn't like the clutter. On Granuaile - an LFH Marco Polo - the tendency to extreme heel made it actually safer and easier to go forward along the lee side, which is where most work you'll have to do is happening anyway.

So for me, a jack line bow to stern as much inboard as possible without getting hung on a dorade or such has been happiest, but it is very much worth experimenting as different boats get different long splices.

G'luck

[benz]

Another less cluttery method is to have no jacklines, and clip a tether to different fixed attachment points as you go. It is actually not too difficult to have two tethers, travel to the end of one, clip the second one in ahead of you, then unclip the one behind. I have all sorts of handy favorite clipping spots all over the boat, suitable for different tasks, but mostly near the centerline. If your tether is rigged like a rockclimber's "Daisy chain", you can effortlessly shorten or lengthen at will, and even wrap it around objects bigger than the clip will accomodate and clip it back to itself. Most handy.