Have I fallen for a p!ss take? Am I missing something? If this isn't a p!ss take then it demonstrates perfectly the dangers of social media
Select to expand quoteToph said..
Have I fallen for a p!ss take? Am I missing something? If this isn't a p!ss take then it demonstrates perfectly the dangers of social media
Pretty bad picture as the yacht should at least be facing the anchor.
I haven't a clue really but thinking it through I guess we need to analyze what will happen when there is a stiff breeze and when the bow of the boat and the floats are going up and down with waves.
The weight of the chain is going to make sure that all three of those fenders or whatever they are float together in a clump when there is not a lot of wind.
If the float nearest the anchor is to keep all the chain off the bottom (as it must to achieve the desired object of protecting the coral) it is going to need to be of a good size if the water is deep and it is going to exert an upward pull on the end of the anchor shank as it goes up and down over waves which is exactly what you don't want when you need the anchor to set. It seems to me that the first float would approximate the motion of the bow of the boat and therefore the setup would be equivalent to having far too little chain out. To be fair however I guess the float wouldn't be capable of yanking as hard on the chain as the pitching bow of a boat as it would probably get pulled under a bit on big waves.
You are going to need a lot of different sizes of fender nearest the anchor to float the chain depending upon how deep the water is.
I'm going to say I don't think I would feel that secure.
On the other hand if there was only a short amount of chain and the rest was nylon the floats might be good to keep the nylon off the bottom and therefore protect it from chafing on the reef at low tide. In that case you aren't protecting the coral from the chain but rather the rope from the coral. Bit of an effort though.
Maybe just look for a sandy patch in between the coral.
Actually it is a very seamanlike technique. It has been around since the 70s. The Pardeys write about using fenders in coral lagoons in big blows.
The problem with not doing this, along with wrecking coral, is that the chain can get caught on bommies. So the catenary you thought you had gets shortened as the chain gets snagged. I think it was in Suvarov where the only boats that survived a massive blow were the ones that used this technique.
A very experienced multi sailor, Jason Gard on Spirit, sailing in the Tuamotus showed a video of him swimming on his tri with the chain bouyed. It's a technique anyone who has to anchor near coral should be conversant with, good for the coral and good for your boat
Well there you go. I had never seen this before.
You would still have catenary to a more or less degree, but the theory that the weight of the chain is what holds the boat is no longer valid, as that chain needs to be on the seabed and not suspended in the ocean putting a whole lot more emphasis on the anchor.
What 'scope' would you use in an anchorage? The idea of "more chain more chain more chain" I though was to lay more on the sea floor to enhance holding power 
They must use light chain or have really big fenders
maybe the answer as always is just put the right amount of chain out
calm night in 5m you won't need 50 m out
So it seems from videos that people are recommending 1.5-2 times water depth to the first float. Presumably this is at high tide. Obviously this gives a really bad angle of pull on the anchor if any serious holding power is required.
Presumably the purpose of the rest of the chain is to improve this angle if serious strain is put on the chain, the floats submerge and the anchor really needs to dig in. In order for it to do this that first chain holding float needs to have barely positive bouyancy at rest and therefore readily submersible in stronger conditions. Same with the rest of the floats. If not sized absolutely correctly it would seem that the end of the anchor shank would constantly be tugged upwards by wave action thereby destroying the set and the anchor would definitely drag.
An extremely delicate balance which one would have to get exactly right and I'm still not thrilled about the idea. In fact as this balancing act totally changes from low tide to high tide when the weight of suspended chain can be very substantially more it isn't even possible. Am I missing something?
True I have never had a bommie snag my chain but weighing that possibility against the possibility that my anchor will never set properly I think I would take the risk with the bommie snag. Of course avoiding anchoring in coral in the first place is the best policy if it all possible.
Had to laugh at the caution in the video saying watch out people don't mistake your floats for a mooring ball :). Maybe a 24-hour vigil is required.
Never heard of the system before but now I'm starting to see it everywhere such as from 30 seconds to one and a half minutes point in this YouTube channel.
So my 26 foot trailer sailer is pretty light therefore I don't want to carry too much chain not to mention I have to tow the weight with my car as well and it's a long way from Sydney to places like Airlie Beach.
Typically trailer sailers carry about their length in chain and the rest of the rode is nylon or something (I've got 11m plus another spare 10m that Ive not deployed yet). I'm dead scared in the Whitsundays that at low tide the nylon will wrap around a bommie perhaps due to a slack time when the tide or wind changes and then chafe so that I will wake up at 3 a.m. adrift on the reef or who knows where.
Yes I do set an anchor alarm but last time it drove me nuts going off due to loss of signal or something.
I know that nylon has some give in it which is ideal for anchor rode but it doesn't float. What do people think about using silver rope so that it floats and therefore hopefully won't get snagged around coral? A short bridle with a couple of those rubber shock absorbing thingies might be adequate to prevent any damaging and uncomfortable yanking from the rode if the seas build up a bit during the night.
I guess this is similar in some respects to having chain suspended on fenders but is unlikely to suffer a destabilizing upward pull on the anchor. It may however in a stiff breeze exert a destabilizing pull due to shocks and lack of stretch.
Might be a hazard in a crowded anchorage but if not crowded.Thoughts?
