Jacklines and Tethers

[jssailem]

Over the past few years we have had several discussions about Jacklines and Tethers. Some have been for a specific boat i.e. 38 Hunter owner or The Solo Sailor.

Lets start with a definition of terms.

• Jackline - A line or strap attached to the boat in two places running along the deck. It is designed to be a safety line onto which you can connect a line to your body. You can use the line to grab and hold should you be sliding across the deck.
• Tether - A length of line you attache to your body (harness) that you can tie to a strong point on the boat or you can attach to a jack line and let it slide along the jack line as you move across the deck.
• Harness - a rig you wear to secure your torso to a tether. There are PFD's that have harnesses designed in the device or you can find just a set of straps designed as a harness to fit over your torso.
• STRONG POINTs - These are specific fittings on your deck that you are going to trust with your life. You use to attach jacklines or tethers to strong points, thus anchoring you to the boat.

Confusion is easy when we use terms about sailing. This was nicely pointed out by @thinwater here Advice for a Solo Sailor?

I had to discard most of what I learned about the set up of Jacklines once I read the information and discussion developed by John Harries of ACC.
Harries recently added this article to his Tips for sailors. Sidedeck Jacklines Worse Than Nothing?

Reading the testing done by the Practical Boat Owner crew may be eye opening. Is it safe to use a tether? - Practical Boat Owner

Sailing is an exciting sport. Bringing your crew home safe is an obligation we as boat owners take on when we invite guests to experience our sporting activity.

The Jacklines on SV Hadley run from the cockpit to mast and then to a strong folding padeye on the foredeck - 2 lengths of about 8ft between hard points. Tethers are attached to the jacklines. Using them you attach the tether to your harness point. The tether slides along the deck to the next hard point. You proceed forward clipping in the next tether, then unhooking the last tether. This means you are always attached to the boat. The length of the tethers is designed to allow you to move about the boat but keeping you inside the life lines and out of the water.

BE safe.

 

[rgranger]

good read. Thanks @jssailem
So the take away is to use a short teather on the windward jack-line and stash a snorkle in your pants in case you fall off the leeward side...

 

[MikeHoncho]

Plan A - Don't depend on anything but three points of contact (while using my Jackline and tether). Plan B - Use Jack line and short tether designed to keep me inside of the lifelines. Plan C - Miscalculate and end up over the side using my lifeline and tether and cut away with my dive knife attached to my PFD and depend on my PLB (also attached to my PFD.)

 

[thinwater]

You don't have to walk tall. There is nothing wrong with crouching, crawling, or scooting on your butt.

Whether jacklines and tethers are safe depends on how they are used. Run the jackline along the edge and used the nice comfortable, 2 meter tether, and yes, obviously it's pretty useless. This is largely a result of attaching them to the most convenient points, the cleats, which is all wrong for several reasons:

• Cleats have other uses, including anchoring, docking, and rigging riding sails. They should be clear for those uses.
• They are the wrong place. There is ZERO reason for a jackline to run closer than 4-5 feet to either the bow or stern. There is ZERO reason for the jackline to be fully outboard. So since we are going to install new hard points we should chose those best for the specific boat, which will vary.
• A jackline is not the best answer for every purpose.
  • Very few sailors fall while moving, because they are holding on and paying attention. They fall when working at the bow or in the cockpit. You should clip to a local point whenever possible.
  • Jacklines are only rated for one sailor at a time. Another reason to clip locally. That does not mean you can't keep the secon tether leg on the jackline. But clipping at the bow, in the cockpit, or to the mast makes sense.

 

[David in Sandusky]

Our jack line is the port bow line run through a hard point on the mast to a hard point on the starboard side of the companionway in the cockpit. We rig it before getting underway and unrig after docking on the starboard side (or before docking on the port side.) New, shorter tethers will keep us inside the lifelines when clipped on. The Captain is always tethered to the jack line or a hard point unless there is a crew member (other than the Admiral) qualified for MOB pickup. All crew are tethered going forward in rough weather, The Admiral has decided to be tethered when going forward alone. Because it starts in the cockpit, the centerline jack line is easy to hook on to before leaving the cockpit.

An SBO discussion on this topic a few years ago resulted in moving the jack line to the centerline from the side deck(s) and the newer, shorter tethers. Since I do not sail solo, the previous setup along with rigging the vang as a fall on the end of the boom would have allowed recovery from the water after heaving to.

 

[Will Gilmore]

Just to be clear, jacklines are not the same as lifelines. Don't use your lifelines as jacklines; they are too far from midships. If possible, rig your jacklines at waist height or higher to make it easier to reach, keep it farther from the side, reduce downward pull on the tether, and less of a trip hazzard. Also, assess where the ends are attached to, as they are likely to be where your tether clip will slide to, should you lose your grip in a deck washing wave and you are tumbled along the jackline to fetch up on the terminus.

-Will

 

[Hello Below]

You don't have to walk tall. There is nothing wrong with crouching, crawling, or scooting on your butt.

 

[dLj]

Having spent some time reading jackline advice from many seasoned sailors, I have followed the advice of @thinwater and others in setting up mine for my current sailing.

Given the geometry of my specific boat, it's not possible to have one jackline run for use bow to stern. So I need different attachment points. So I've attachment points set up in my cockpit area and long jacklines running from the forward edge of my cockpit to just short enough toward the bow to still be able to work there also tethered in without risk of ending on the wrong side of the lifelines.

It is the transitions between connection points that we practice such that we are always tethered on even when changing between attachment systems. We use double tethers with a long and short tether that allows reaching the long tether to the next attachment more interior then releasing the short tether, or vice versa depending upon coming or going. These transitions must be practiced such that they become almost second nature. In pitch black night, in pea soup fog, I don't want to be thinking about how am I making this change while a wave is chasing me down the boat...

My policy is to be tethered in at all times. Sure, during the day with calm seas and low wind we may be in the cockpit without being tethered, but those are exceptions and for sure only during daylight hours, calm seas and only when not sail handling or anything that might cause one to loose balance, slip, whatever. At night, no matter, tethered in 100%.

I strongly feel you must move everywhere on your boat using your tether and all transitions be established prior to setting sail. Practice these movements before you "need" them.

dj

 

[kappykaplan]

Practice these movements before you "need" them.

 

[thinwater]

...Practice these movements before you "need" them.

So true. Work the systems out in fair weather, so that clipping is easy and tangle are avoided. If the tether makes anything more complicated, then it's rigged wrong ad now is the time to fix it.

This is also the reason I favor permanent jacklines. The problems with webbing that is set only when needed are many:

• They are set from the cleats, which is wrong.
• You don't have time to practice with them.
• They aren't there when a sudden storms comes up. You'll be fumbling around setting jacklines when there are other things to be done.

Instead, make them from something more durable and leave them set. Dyneema covered with webbing works. Rope works if located so they are not underfoot. Another advantage of >3/8" rope jacklines is that they double as hand holds. Do use a type of rope or color that is distinctive from all of the lines on the boat. Bright orange could be smart, though I've always used something I had.

 

[rgranger]

Bright orange could be smart, though I've always used something I had.

This has been a very great discussion. Thanks @jssailem for starting this discussion. I like @thinwater 's idea of a different color line for the jacklines.... BUT, my experience has been that reds and oranges don't hold their color in the sun. I guess that makes sense since things that are orange and red are absorbing blue photons (the higher energy side of the spectrum).

And speaking of UV resistance, Polyester is more UV resistant that Nylon so that might be worth throwing into the equation. Dynema is a blend of high density polyethylene and polyester. Dynema line can be purchased with a polyester woven cover... so that would be a good choice for both UV resistance and feel.

 

[capta]

Personally, the only time I've used a tether is when I'm going out a bowsprit in heavy weather. However, it is only a line, long enough to get me aft of the boat, and it is tailed by at least one crew, or two if possible.
Before leaving port on a voyage with new crew, I state quite emphatically that if it is too rough to walk, they must crawl on their hands and knees, or even their stomach, when going about the deck. Nobody ever hurries on my boat, for any reason, except possibly the cook. Situational awareness is what saves lives on a boat.
I always get a kick out of folks who say they walked up to the foredeck to check their anchor in a hurricane or cyclone. Maybe I was a weakling, or somehow disabled, but strolling up to the foredeck in a hurricane/cyclone was something I just couldn't do. Crawling there, hugging the deck, I might have the energy to do, though sometimes even that wasn't possible in winds over 125 knots.

 

[DayDreamer41]

After reading the article posted here on Jack lines and tethers I am quite certain that using jack lines rigged to be on the gunnels puts the user in more danger than not clipping in at all. Rigging jack lines on the centerline of the vessel seems to me to be the answer when used with short tethers, but, as the bow does get more narrow I feel it still puts the user in danger if going over, so I really don't know what the right answer is.
If the jack line securing point at the bow is set back far enough to only allow the user to get the tip of the bow it still allows the user to fall over on either side. Changing head sails puts the sailor right at the forestay at which point the sailor is exposed to either side of the bow. I know on our vessel from the mast back would need to have (2) branches (1) to port and (1) to starboard to get around the dodger which is really not a problem.
When traversing the deck the sailor would have (1) tether on the harness to start with and (1) tether would be left on each of the jack lines ready for the transition from line to line.
Having just returned from Mackinaw Island earlier this week with an angry Lake Huron just waiting to claim its next victim it always makes me wary to step out of the cockpit.
Its funny that the Bayview Port Huron to Mackinaw rules to race require jack lines fore to aft on either side of the vessel, I guess they need to do some research on just how dangerous that arrangement is!

 

[Davidasailor26]

Dynema is a blend of high density polyethylene and polyester. Dynema line can be purchased with a polyester woven cover... so that would be a good choice for both UV resistance and feel.

I thought Dyneema was just Ultra-High Molecular Weight Polyethylene by itself. Dyneema composite fabric is dyneema laminated with polyester.

My concern with dyneema for jacklines or tethers is its super low stretch. That’s not really a desirable quality for catching a falling person. It’s also hard to knot and loses a lot of strength when knotted, so it wouldn’t be very adaptable to different boat configurations without extra splice work.

 

[thinwater]

I thought Dyneema was just ultra-high molecular weight polyethylene by itself (it is). Dyneema composite fabric is Dyneema laminated with polyester.

My concern with Dyneema for jacklines or tethers is its super low stretch. That’s not really a desirable quality for catching a falling person. It’s also hard to knot and loses a lot of strength when knotted, so it wouldn’t be very adaptable to different boat configurations without extra splice work. Good point. I've written about this and the engineering answer is long and boat/installation dependent. One size does not fit all. I prefer polyester rope because of UV resistance, if you can keep it out from under foot (rope rolls under feet). Dyneema has enough stretch if the line is more that ~ 35 feet long. The tether has some stretch and they are required to pass a drop test. As for shorter Dyneema lines, if you can limit fall distances that really helps. Don't run short lines bar-tight or the tight rope effect will be monstrous. Go up one size in both Dyneema size and anchor strength to compensate. The upside of traditional polyester jacklines is that they are a very good mix of moderate stretch (for most size boats) and laying flat on deck. The downside is they are not very durable in the sun because they are thin and the UV penetrates. That, unfortunately, that leads to frequent replacement, perhaps annually depending on latitude.

Mine are due for replacement (7 years on 10 mm polyester rope). I may switch to Dyneema, but largely it depends on what surplus line comes along that meets the requirements.

See above