PS Advisor: 08/01/05
My wife and I recently traded up to a new Jeanneau Sun Odyssey 35. It's beautiful, fast, comfortable, and comes with nearly everything we need, except jacklines.
I do a lot of singlehanded sailing, and I think the importance of staying on the boat makes jacklines more useful than, say, a good rescue system like the Lifesling. I've had success using a heavy braided polyester line strung bow to stern on both sides of the boat. I know you've written that webbing or wire is better. Do you have a preference for webbing vs. wire? How about one of the new high-tech lines in place of wire?
PS has written in the past that we prefer webbing or wire for jacklines because both are more stable when stepped upon than line. No one needs any assistance in losing their balance when moving about on a wet, inclined, pitching deck. However, wire can also roll underfoot, so our preference is really webbing.
We should point out that one of the findings derived from investigations into the 1998 Sydney-Hobart Race tragedy is that nylon webbing is too stretchy. Within webbing there are a couple of alternatives. Most sailors who opt for jacklines made of webbing use polyester webbing because it's readily obtainable and sufficiently strong for the task. Polyester webbing has less stretch than nylon, but it will still stretch somewhat under load, so it will tend to lessen the shock-loading experienced by the person whose harness is tethered to it.
Another webbing alternative is Spectra webbing, which is available through sailmakers. Spectra webbing has often been the choice of single-handed distance racers for jacklines. Brad Van Liew, who won Class II in the 2002-03 Around Alone Race on board his 50-foot Tommy Hilfiger, used jacklines made of Spectra webbing. Spectra definitely won't stretch as much as polyester, however, when run over a length of a deck that's, say, 40 feet, the line should deflect about two feet. That, along with the stretch inherent in the tether, should be sufficient to diminish the shock loading.
We've also heard of sailors using the cover of conventional braided line for jacklines. The advantage of using line covers is that, like webbing, they'll also lie flat on the deck and won't tend to roll underfoot. It's also easy to adjust the tension of braided covers. However, the one caveat is that some materials are stronger than others. Check with your line source regarding the breaking strength of the cover before you select this option.