In the last chapter we learned that the tether and jackline systems that most of us use are pretty close to useless, and may even be more dangerous than not wearing a tether at all because of the risk of being drowned or battered to death (probably a combination of both) while being dragged in the water at the end of our tethers.
In this chapter, after all that bad news, I’m going to get positive and look at the changes that Phyllis and I made so our crew overboard prevention system on Morgan’s Cloud, our McCurdy & Rhodes 56, would do its job, rather than just lull us into a false sense of security, as it had been doing for decades.
Key Requirements
Let’s start with a quick overview of the two key requirements the new system must satisfy:
#1 The 1-Foot Rule
In the last two chapters we saw that the only way to eliminate dragging risk is to move the jacklines to a position where the longest tether length in use on that jackline, plus the deflection of the jackline under load, results in the point where the tether attaches to our harness being at least 1 foot (30 cm) from the toerail.
#2 Usability
That said, we actually have to sail our boats in an efficient and effective way and therefore any change must not compromise our ability to easily, and quickly, reach and work on every part of the rig and deck.
To put that a different way, when designing a safety system, if we try and make it 100% safe, there is always the danger (probably likelihood) of making it so difficult to use that no one does or, worse still, that we introduce new dangers in our effort to ameliorate the old ones.
For example, there is no safety at all in a COB prevention system that is so slow and cumbersome to use that it makes reefing so onerous that we postpone doing it, or said reefing takes us too long when we finally do get to it.
The good news is that our system is now both far safer and easy to use. Let’s dig into how we accomplished that:
You say you are keeping the cockpit jacklines as they are. It’s hard to see in the picture exactly what you have there. Looks like one bit of webbing on each fore and aft cockpit seat, just behind the knee of someone sitting there. Is that it? Seems nice and simple.
Hi Steven,
Yes, you can see the yellow jacklines on the top of the front faces of the seats. Thanks for pointing out that was not clear, I will fix that.
Hi John, Interesting reading (as always).
A tip that some might find useful. We use a Grillion, https://www.petzl.com/GB/en/Professional/Lanyards-and-energy-absorbers/GRILLON-HOOK-international-version
It is just brilliant. No short/long tethers that get in the way. Very easy to adjust, so you can for instance go down on your knees on the foredeck, tighten up the cord, so the tether is tight. The Grillion must not be confused with a GriGri which is used as a descender when climbing. For me mowing on the deck – a game changer. Some might use it for strapping to the mast (so far I had no need for this). You can find various instructional videos on the net.
Cheers / Colin
Hi Colin,
Interesting, but if we are going to discuss alternative tethers let’s do that on the applicable chapters: https://www.morganscloud.com/2017/02/20/the-right-tethers-to-keep-us-aboard-part-1-a-mix/
Hi John,
Opening the foredeck hatch when in offshore mode – let off the tackle up forward? Your tackle solution sidesteps this problem neatly.
Also, I typically use a hard point back from the bow when working up there, using either a short or long tether depending. on how far forward I need to reach.
Centerline jacklines, especially on smaller boats is the best way to go.
You didn’t mention moving aft?
Whitall
Hi Whitall,
Moving aft in the next chapter: https://www.morganscloud.com/2016/11/11/banishing-sidedeck-jacklines-forever/
I should probably consolidate that into this one. I will put it on the list.
Since using this method of jack lines, I have felt a lot safer as I move about the boat. Getting familiar with multiple tethers took a little training. Learn by moving slowly. Slow is smooth, and smooth is fast. Utilizing one side (starboard, for me) is optimal when leaving the cockpit. My boat is not as wide as your Morgans Cloud. Moving to the mast puts me at the control lines I need to access.
This is really helpful for me as I am doing a full refurb on my Shearwater 45, and naturally re-examining deck layout and pad-eye locations. One thing that’s not clear to me, though, is how you transition from the cockpit to the deck: you say “clip to a tether attached to the new cabin-top jackline before unclipping from the cockpit tether” so do I assume that there is a tether (already attached to the cabin-top jack line) and this can be accessed / clipped onto from the cockpit before unclipping from the cockpit jack line? Does it hang over the dodger?
Hi Steven,
This is only one chapter in a full Online Book on COB prevention with several chapters, and a demonstration video, showing how the system works and explaining in detail how to build it.
So you really need to at least skim the whole book before taking this on. Not to worry, it’s a fairly short read: https://www.morganscloud.com/category/safety/book-crew-overboard/
John – I have read it all and have used it to configure and spec my system…but (I must have missed it) I don’t get the transition from cockpit jack line to deck jack line. As you have indicated, the tether resides on the jack line, so I assume (??) that after tethering in the cockpit, the tether from the deck jack line is accessed and clipped on, then cockpit tether unclamped, then exit the cockpit to go forward. My question is about the deck tether – where is it “hanging” for easy access, esp. bearing in mind that it’s not very long. Aaaargh! This is hard to explain 😱
Ok – I just watched the video again – now I get it! I can see where the deck tether has been picked up. Thank you!
I like cabin top and have set that way before but depends on the ability to move inboard of the boat shrouds, right John? Otherwise, you’re doing a ‘biner swap at the shrouds. Done that before too but not enjoyable for fast movement to the mast.
Hi Tom,
Yes, that’s true, but it’s no problem on most any boat, because you will either be going just to the mast, or changing to the foredeck jackline and tether, see the next chapter.
Hello,
what is your opinion on chest or eye level dyneema jacklines rigged on the inner lower shrouds. Johnson mskes a special clamp eith an eye.
John Neal had published pictures of this system on Mahina Tiara III.
Thanks
Hi Dennis,
I’m not a fan: https://www.morganscloud.com/2025/03/27/flawed-jackline-systems-revisited/
I would suggest that before doing anything on your boat you at least scan the entire Online Book, not just this chapter: https://www.morganscloud.com/category/safety/book-crew-overboard/
Good stuff.
One thing I have done is to end the jacklines about 4 feet short of the bow and stern. In this way I can leave the long tether on the jackline and still reach the bow, and I can clip my short tether to the pulpit or some other hard point for additional security. I may be sitting at this point. While on a mono the risk is often heel and sliding, on a multihull the risk is a sudden slowing from stuffing a wave throwing you forward. Sometimes I even double the short tether around the pulpit and sit. The bow can play submarine and I will only get wet.
Same aft. I like the jackline to end such that I can just reach the opposite corner of the cockpit, and certainly not past the stern rail. I have always feared simply tripping over my own feet and going over the rail. Most falls happen when you are focused on something other than safe movement. If the boat is outboard powered, dragging just aft of the transom is a scary thing. There’s a chopper there.
Hi Drew,
Good suggestions. I too have terminated the forward jackline well aft of the bow of the J/109. More on that system, focusing on the challenges of smaller boats, in a future post.