Stay Safe at Sea With a Custom Jackline System

A study by the U.S. Coast Guard found that from 2000-2011, drowning accounted for 73% of sailing deaths. It’s a senseless tragedy when a sailor goes overboard because they aren’t properly tethered, or they’re tethered but get dragged alongside the boat and drown because the tether is far too long. But the worst part is that these deaths could easily be avoided if the sailor had installed a safe and useful jackline system.

Longtime Sailrite customer Captain Donald Quackenbush is a veteran sailor with 28 years and 100,000 miles of sailing experience. He’s been a 100 Ton U.S. Coast Guard Master Captain for 20 years and, as a member of the National Boat Handling Committee, created the Man Overboard System that is taught by the U.S. Power Squadron nationwide and is also available as a college course at the University of West Florida. He has generously offered to share his vast knowledge on sailboat safety measures with us. Everyone should feel safe on the water, and Captain Quackenbush’s system is set up in a way that, when properly installed, will prevent you from going past the toerail and dragged through the water.

One of the greatest benefits of Captain Quackenbush’s system is that it offers sailors the “third hand” so often needed while at sea. The tethers are shorter than most popular tether options on the market, meaning you don’t have to hold the tether with one hand as you move around the boat. This hands-free system gives the sailor freedom of movement compared to commercial jackline and tether setups. It enables the sailor to lean or pull against the tethers while working, offering support and stability. The three key parts of the captain’s jackline system are the location of the padeyes, the length and construction of the jacklines, and the short legs of the “Y” tether. We’ll cover all three aspects below and show you how to install this lifesaving jackline system on your boat. Captain Quackenbush has installed his jackline system on several customers’ boats over the years with excellent results and a perfect safety record.


Captain Donald Quackenbush demonstrating the third-hand capabilities of his jackline system.

Installing the Padeyes

The first step is to install the padeyes in the correct locations. Most sailboats will require eight padeyes. Install a padeye right outside the companionway so you can hook yourself in as you exit the cabin during severe weather. The helmsman should always be tethered while on watch, so install a padeye in the cockpit (a second padeye at the aft end of the cockpit may be needed on larger boats). A padeye should also be attached near all four corners of the cabintop so that the jackline runs down the halfway point between the toerail and the boom as near as possible. This should make it possible to reach the boom and toerail but not go past either point.

Finally, two padeyes are installed on the foredeck, one center aft and the other center forward. The aft foredeck padeye should be reachable from either forward end cabintop padeye without unhooking. The padeye at the forward end foredeck should be forward enough so that you can reach the anchor, windlass, etc., but aft enough so that you can’t fall off the boat at the foredeck. Captain Quackenbush recommends through-bolting the padeyes as you will put a lot of pressure on the system if you slip or a wave sweeps your feet out from under you.

This schematic shows padeye and jackline placement on a boat.

It’s not necessary that the padeyes are placed the entire length of the foredeck and cabintop. The most important factor in padeye placement is that you should be able to move around the entire boat and never be unhooked in severe weather. So as long as you can reach the next attachment point without unhooking yourself from the current one—and the padeyes are far enough from the edge of the boat to not be able to fall overboard—the system is set up correctly.

You may be wondering why you can’t just use the cleats to attach the jacklines instead of installing padeyes. The reason is that the entire goal of Captain Quackenbush’s system is to keep you on the boat at all times, and the cleats are too close to the edge of the boat. Even with a short tether, you would still roll over the side of the boat. During inclement weather, this is the last thing you want to have happen. It’s incredibly difficult to hoist yourself back onboard when you’re being tossed around and soaked by a merciless storm, especially if you’re a solo sailor. Usually it’s impossible.

Jackline Do’s & Don’ts

Once you have the padeyes installed, the next step is adding the jacklines. You will have three jacklines on your boat: one each running along the port and starboard sides of your cabintop, and one running aft to forward on the foredeck. The beauty of Captain Quackenbush’s system is that with jacklines running along the cabintop and down the center of the foredeck, and with shorter tether lengths than commercial offerings, nothing will ever be around your feet and ankles as a potential tripping hazard. Captain Quackenbush uses Dyneema or Spectra webbing for his jacklines. Both have very little stretch under load, have good UV resistance, and the padeye knot or hook holds the webbing up at each end, making it easy to hook in. Another benefit to using webbing is that it is flat and, therefore, won’t become a tripping hazard should you step on it. Never use wire or line as they can roll underfoot. Be sure to pick a webbing color that is visible at night and easy to see. White seems to work best.

Jacklines running along the cabintop.
The foredeck jackline and cabintop jacklines within reach.

The jacklines are removable for easy repair and storage. Sew a hook to one end of the jackline to clip to the padeye with repeated or heavy stitching (92 or heavier), and then tie the other end to the opposite padeye using an anchor bend and two half hitches. Or, you can tie both ends if you choose. Because the webbing is nonstretch, the jacklines don’t need to be tied super tight. The sun is your jacklines’ worst enemy, so storing them when not in use will help to prolong their life. Captain Quackenbush says his jacklines last about five to ten years, and he sails about 250 days a year. To check the quality of your jacklines, take them to a quiet location, hold the webbing up to your ear, and flex it. If you hear crackling, that’s a sign your jacklines are becoming brittle and need to be replaced.

Creating the Tethers

Now that you’ve got your padeyes and jacklines installed, the final step is sewing your own tether for your harness. Captain Quackenbush recommends a Y tether, meaning it’s shaped like a Y with one attachment point at the harness and two legs that attach to the jacklines. The central hook should be heavily sewn with a box X stitch and heavy UV thread as well. Go over it several times as you sew it. The hook that attaches to the harness should be brightly colored and easily visible at night (Suncor Poly Grip Harness Clip #103763 is a great choice) should you ever need to unhook in an emergency in poor visibility.

The tethers are made with tubular webbing with a heavy bungee cord inside to shorten them further when not in use. One tether leg should be shorter than the other so that you have a choice of tether lengths based on where you are hooking in on the boat—the leg for the foredeck jackline is typically the shorter one and the cabintop leg is typically the longer one. Determining the lengths of your tethers will require some measuring and experimentation on your boat. Create a Y tether with longish legs and tied on hooks, then go out on deck and determine the distance you need from the jacklines to just reach the toerail and boom with considerable pressure. Do the same with the foredeck jackline. Once you have your measurements, you can finish constructing the tethers and add the internal bungee. Sailrite offers tether kits or supplies sold separately to make your own custom design.

A completed two-leg tether system with one leg shorter than the other.

The genius of the two-leg tether system is that you can move around the boat from one jackline to another without ever unhooking. Two tethers also allow you to be attached to a jackline and another spot on the boat, such as the mast, for even more security. This is a huge safety advantage and can be the difference between staying on your feet or being tossed around when the boat is pitching and rolling during rough weather.

Proper tether and jackline lengths are determined by the size of the boat. Every boat requires a separate setup. Jacklines should be located halfway between the toerail and the mast/boom. The padeyes should be placed so that you can move from the cockpit to the jackline, and then from one jackline to the next without ever unhooking. Simply switch back and forth between the two tethers as you move around. Keep the unused tether hooked back on the D-rings of your harness when not in use. Spending a bit of extra time during the planning stage—taking measurements and experimenting with padeye placement, and jackline and tether length—will ensure your safety while sailing. And that peace of mind is priceless.

The problem with commercial tether and jackline designs and kits on the market, according to Captain Quackenbush, is that they allow the sailor to fall off the boat and get dragged through the water. The tethers are so long they drag around your feet, getting tangled and tripping you. This requires you to constantly hold the tether up off the ground, leaving you with only one working hand and creating a very dangerous situation in rough weather. Likewise, jacklines located along the side decks also present a serious tripping hazard. The annoyance and inconvenience of these commercial tethers and jackline kits is why so many sailors don’t use them in favor of faster and easier movement around the boat. A deadly gamble.

A Message From Sailrite

We at Sailrite feel confident in recommending Captain Quackenbush’s jackline system to our customers. In fact, here’s what Owner and Vice President Matt Grant has to say about this system:
“Captain Quackenbush is a longtime Sailrite customer with a keen understanding of safety and self-reliance at sea. His system makes perfect sense and his sole motivation in helping Sailrite to write these instructions is to save lives. Sailrite applauds Don and others like him who encourage safety at sea and are willing to freely share ideas.”

We’re hoping that by spreading the word about this great safety system we can help keep sailors safe and—most importantly—stay on their boats! Sailing is a wonderful sport and hobby, and it should be enjoyed to its fullest at all times without the worry or concern of your tether and jackline system failing you.

Visit for all the supplies needed to install Captain Quackenbush’s jackline system on your boat:
-8 Harken Folding Padeyes (#320611)
-1 Suncor Poly Grip Harness Clip (#103763)
-2 Suncor Asymmetrical Wire Lever Harness Clips (#103760)
-Dyneema 1” Webbing (#106406) desired yardage

Disclaimer: The information in this article is the opinion of Sailrite Enterprises, Inc., and is not corroborated or verified by a sailing safety authority. Sailrite shall not be held liable in the event of injury or death. Use at your own risk.


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12 thoughts on “Stay Safe at Sea With a Custom Jackline System”

  1. Thank you for publishing this. It will serve all of us who sail extensively (or even just a little), to give more thought to this most fundamental safety requirement: Stay on the boat! I sail on the Inside Passage in the Pacific Northwest, and going overboard can easily be fatal.

    After experimenting with various jackline configurations, I found most to be cumbersome and prone to creating their own hazard (from tripping). I’ll look harder at this in light of Captain Quackenbush’s recommendations. My boat is small – 26 feet on deck, and her deck is the more cluttered for it. My own solution is to use a spare halyard (my tops’l halyard) cleated to a length that allows me full travel on the deck, and which should keep me out of the water in any circumstance.

    I’m aware that this solution has its own limitations as well, but most every system does. Reading this article will occasion a rethinking of my approach, and possibly to change or modify it.

  2. Thank you for this useful information. I love the Y shaped harness design which enables you to double clip between jackstays and the bungee to keep it shortened. I will recommend adopting this harness system on our rescue vessels.

  3. Smart !
    I would consider to use something more than a 1“ Dyneema Web band. The 1“ brakes at aproxx 3800 lbs. The load required for one person is 1024 lbs of i am not malinformed.
    That makes 2048 lbs for two. Now add 30 – 40% (from total) for The knots. Allow some safety margin as well , this way the whole system as described is on the risky side.
    I always have a short Loop around the mast. That allows to hook in while working on the mast. This loop works fine with a 10-12mm dyneema rope.
    In addition i feel comfortable to carry a piece of rope (about 10ft) on my belt to fix myself or something while in working position.

    I agree, we should avoid all all cost to fall over board.
    Fair winds !

    1. Hi Peter,

      The 1″ Dyneema webbing we sell at Sailrite has a minimum breaking strength of 4,540 pounds. We also sell 2″ Dyneema webbing with a minimum breaking strength of 20,590 pounds, which would definitely be more than enough strength.

      Thank you for the tip about keeping a short loop around the mast for hooking in. That’s a great idea!

  4. Hi Hayden,

    We asked Captain Quackenbush to take pictures of his jackline system so our readers could have a better visual of what the setup looks like. He was not out at sea at the time and was near shore when the pictures were taken. When he’s really sailing he keeps his dog securely tethered to the boat in the interest of safety. Thanks!

  5. This design is incredible! You most certainly know how to keep a reader entertained.
    Between your wit and your videos, I was almost moved to start my own blog (well, almost…HaHa!) Great job.
    I really loved what you had to say, and more than that, how you presented it.
    Too cool!

  6. Hello there! Do you use Twitter? I’d like to follow you if that would be okay. I’m absolutely enjoying your blog and look forward to new updates.

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