Tether length

barrow_matt

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I plan to mostly sail singlehanded in a 19' boat and was wondering what an appropriate tether length would be? Is there a rule of thumb for this based on the boat length?

Should there be a loop so whilst in the cockpit it is not possible to go overboard, just enough to lean out over the railing or is that dangerous in a larger boat as you wouldn't be able to quickly clear the hull of the boat if a full capsize was occurring?
 

sarabande

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what do you mean 'tether' please ?


Is this a line to prevent you falling over (normally called a 'jackstay') or a line to tow you along after you have fallen over ?

Most boats fit jackstays from the bow to a point near the cockpit, so that you can clip on as soon as, or before, you reach the cockpit.

19ft ? Sounds as if you are planning some serious sailing to capsize completely. How much offshore or coastal sailing have you done ?
 

barrow_matt

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A tether to stop the boat sailing away without me if I go overboard and yes there is a rail at the back of the cockpit to attach this to.

I'm not planning on capsizing but always best to consider every possibility.

I am new to sea boat sailing coming from a dinghy sailing background.

Is it actually safer to use a shorter tether that you can move around the boat that prevent a wave from putting you overboard on the basis that a boat capsize is very unlikely, also less to trip over in the cockpit! Keep a longer one in a hatch to use when necessary?
 

Searush

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Many personal life lines come with 2 tethers on a single hook attached to your harness. One tether is long (4-5' say) for easy movement & one is short (2-3' ish) so that you can lean back on it & use both hands if necessary. When not in use, these can be clipped back onto the harness leaving a shortish loop dangling. Too long a tether & you will trip over it when not fastened on - & then probably fall over the side! :rolleyes:

If your 19' boat has a keel or 2 it is extremely unlikley to capsize (unless you are planning rounding Cape Horn or similar). Even centreboarders should be designed with adequate fixed ballast to prevent capsize. Catamarans, too can be designed so that the rig gives way before they capsize, or with self-inflating masthead bouancy to prevent it turning turtle.

Capsize is very unlikely to be a problem, slipping or falling overboard might be, which is where the tether(s) will help. A Jackstay is a line run around the deck or cabin top from bow to stern (or cockpit) usually on both sides. You can then clip your tether on to this & walk (pretty well) freely up & down the deck. Slack in the jackstay increases the distance you may fall compared to a fixed point connection.

By & large, stay in the cockpit & you will not fall overboard, the risks occur when working at the mast or foredeck & moving along the side decks or over the cabin roof (assuming you have a cabin roof or side decks). Clip on when you leave the cockpit if you feel there is any danger.

Falling in is most common from the pontoon or when boarding/ leaving, especially to/from a dinghy. Buoancy aids & life jackets are probably more relevant for that risk.

Enjoy your boat & stop worrying. :D
 

sarabande

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the purpose of your 'tether' is stop you falling overboard in the first place.

So it has to be short, and capable of attachment and movement along the length of the boat. Hence my concern over jackstays (lots of references, even recently, if you search).


If you are sailing coastal / offshore, and do go overboard, consider the following:-

4 knots is a shade over 2 meters per second. Say it takes 10 seconds for you to surface, orientate yourself, overcome thermal shock, and the difficulties of swimming with an inflated life jacket, and head back to the boat's track, you will be over 20 meters behind the boat. If you are going to trail a safety line, it will be about 25 meters long - and then you have to pull yourself back to the boat and get on board somehow.

Lots of devices have been thought up to ease the boat's sails by a pull on a safety line, but you still need a ladder or some means of hoisting yourself back on board.

Moral. Don't fall overboard in the first place. So think jackstays and clipping on.
 

barrow_matt

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Thanks all.

Can't wait to get out now, boat sitting on the trailer outside the house, checked all the electrics, did the antifouling at the weekend, got my membership for the local club, just trying to obtain a mooring as I know it would be a pain to bring in and out of the water!
 

electrosys

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If you are sailing coastal / offshore, and do go overboard, consider the following:-

4 knots is a shade over 2 meters per second. Say it takes 10 seconds for you to surface, orientate yourself, overcome thermal shock, and the difficulties of swimming with an inflated life jacket, and head back to the boat's track, you will be over 20 meters behind the boat. If you are going to trail a safety line, it will be about 25 meters long - - and then you have to pull yourself back to the boat and get on board somehow.

Woefully optimistic. Apart from the shock of landing head-first unexpectedly in freezing cold water in the middle of the night (worst-case), in order to "head back to the boat's track" you'd need to spot where the boat now is - from a 'height of eye' of what, 10" ? In a lumpy sea (or why else did he fall overboard ?) it might take minutes to rise up onto a crest. And if it's at night with a moonless sky (Sod's Law applies) spotting a boat from the water won't be easy. Even if/when you do spot the boat, you've then got to make a decision (in the dark) or whether to swim left or right to find the line - which will be invisible ... ... because of course, it'll have no floats attached - which are damned difficult to spot in a chop, even from the deck in full daylight. A line without high-vis floats stands absolutely no chance of being seen, only touched.

Add to all this the possibility of the person sustaining an injury whilst 'going over' and trailing a line of any length just ain't a feasible method of MoB recovery.

DON'T FALL OVERBOARD if single-handed is the only sure way of staying alive.
 

GrahamM376

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DON'T FALL OVERBOARD if single-handed is the only sure way of staying alive.

Very true. A few years ago, I remember reading a case where someone died attached to his lifeline.

If it's long enough for you to go in the water, with the attachment point on your chest, a moving boat can tow you under - just like those triangular trawls used for towing fishing feathers. In this case, the guy drowned dispite his wife being on board, instead of stopping the boat she tried to haul him up but couldn't.
 

prv

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There's nothing stopping you looping the 'long' personal lifeline around the jackstay, then back to your harness-ring

As a matter of interest, that was officially deprecated on Stavros a few years ago after a study of harness use by the MCA. They were concerned about the middle of the tether being chafed and eventually failing. None of the "official" routes around the rig now involve a doubled tether, although as a deckhand having to get to less well-travelled parts for maintenance it's still often the only way where there's nothing you can get a clip around.

I say "as a matter of interest", as the conditions of use are clearly very different to the average yacht - I'm not suggesting that there's anything wrong with looping a tether there.

Pete
 
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