anchoring in water 500m+ deep

If I wanted to lay a mooring in that sort of depth, I'd say the conventional way would be ~8mm wire attached to a clump of chain, usually about a half ton. The wire is better than rope because (a) it won't twist and kink and (b) it offers less cross sectional area to the current. I mention this because it is the sort of thing that is done regularly, so its a known starting point. Knowing the current is the key to working out the "knockdown" a surface buoy would suffer. The forces on the rode in any current are probably going to exceed anything that the boat will apply. There are programs to calculate this sort of thing, but is not really my area of expertise, I only know enough to bullshit a little and tell you what I've done and seen done. (this is SB and not R2R after all :-) ).

For anchoring a boat, you are going to try and achieve zero knockdown. Obviously. You are also not worried about where the boat ends up relative to the anchor, so can put out a reasonable catenary. You will probably be anchoring in stiff mud (pelagic sediment), so a big plough or bruce should hold. 600m of anything is going to be hauled in mechanically, the weight will be quite significant. I would still be inclined towards 600m of wire on a drum or small portable winch, unless you are really sure that there are no currents down there. Otherwise you mite end up letting it all go rather than risk dragging the boat under once the anchor has bitten. It also takes up a lot less room. If you are doing it as an experiment, it might be worth putting it all out with a big mooring buoy (48") on the top and tying up to that. That way, if recovery proves impossible, at least you could get to use the mooring again.
 
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Best bet would be to lower the water a bit.

Do you mean that he should pay to the officials to keep the Gibraltar dam open during the lunch hour ?"

Probably easier to run a hose pipe from the Med to the Dea Sea, suck on the Dead Sea end and start a siphon going. There's also that depression in the Sahara, the Qattara Depression, that Montgomery and Rommel got a bit heated about. That could do with filling up. Might make a nice winter vacation spot. Ships of the desert sort of thing.
 
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One alternative is to lay a mooring, so you don't have to haul in all that line every time you want to go out there.

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If it's a regular anchorage I think this is an excellent idea. For the cost of a big rock, a reel of rope and £5.99 anchore trip buoy, got to be worth giving it a go?
 
Ah, if it's swimming that you want to do then a soft rope attached to a fender should do the the trick. If the boat drifts with the wind then the line will stretch out and you should make a rule that nobody goes aft of the rope.

All fine and indeed good fun if the boat is going a knot or so but if the wind makes your boat drift any faster than that then there's something to hang onto whilst you get everybody back on board. After all, you wouldn't want to go swimming in much of a breeze, presumably.
 
Re: anchoring without an anchor

Wouldn't bother with an anchor if 100m of 12 mm chain.
Better: small steadying sail aft (as on trawlers) and a drogue out front. And maybe leave the 100 m of chain + hook dangling so if mother earth comes up to meet you etc.
 
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Might make a nice winter vacation spot. Ships of the desert sort of thing.

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Right and when the glacier of Greenland is now melting that would bring nice fresh water to the holiday site especially if the Gibraltar dam is open
 
I have anchored in the middle of the channel. recovering the anchor from 60m was a total pain. Personally would consider use of a grapnel and 5m chain + fairly light rope as otherwise the weight for recovery would be excessive. For supply of cordage of this length go straight to the manufacturer.
 
Hm, good point.

I am keener about using an anchor otherwise it will take all morning to find a sneakily submerged mooring buoy that could easily get moved about in a storm, really.

So! i reckon a few reels of 200m floating line on a kedge will probly do it, all nicely cncted with double bowlines.

When i've had enough, i move forward, transfer to a bridle on the stern, and motor inshore with submerged yet "flying" anchor to say 100-200m depth and haul it in mostly by hand. Maybe.
 
So where is this magical spot that warrants the expense and effort of 500m anchoring? Or is it a secret? /forums/images/graemlins/wink.gif And aren't you bothered about snaring the odd passing sub with all this string and chain dangling about?
 
there are shallows in the med, if you just want to be a few miles from shore and anchor you can do that in 12 m and less!!

Its nice to do but watch the forcast as your out in the open and why wait for bad conditions for nothing! Lots of the shallows are a long way from a safe anchorage.

I used to try to plan on arriving at one of these for lunch!!And they can be crowded in summer!!!!!Its the med and everyone has a boat with a large engine there.
You used to be able to fill up with tax free diesel and other things but i expect the EEC banned that??? I never filled with diesel as you had to buy more than i would need.
 
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