anchoring at sea

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johnny_h

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It's probably a really daft question but I'm pretty new to boating, so please bear with me.

I have a small boat and am wondering about using the anchor while out at sea. How does it work in terms of depth? If I throw the anchor over and I'm in sea which is deeper than my anchor rope is, is there anything I can/should do? Is there any sense in it dangling there? Should I just get a longer rope? I've done this in a rib on my PB level 1 course, but I assume the instructor knew the depths etc. Whereas if I go somewhere I'm unsure about, what do I do if I'm in really deep water?

Thanks for your help on this.

For info I have a small 5.5 meter powerboat with a grappling anchor attached to an anchor chain and anchor rope bought from the people who supplied the boat. I've no idea how long the rope is though!

Thanks
 
you need anchor line about 4 times the depth of the water. An anchor dangling over the side and not reaching the bottom is clearly not going to work. as regards anchoring in really deep water - you don't really want to be doing that. You will want to anchor inshore in sheltered water.
 
Looks like you need a bit of training. RYA powerboat 2 books are available, most of this stuff is in there. BAsically you'll need at least 3 time the depth in rope/chain.

Grapling anchors are great for scaling castle walls, not much good for anchoring. Danforth or similar is a good cheap solution, you can get them in a kit with chain and rope at the chandlers.
 
you can use a form of anchor, but they are known as sea anchors, or drogues.

All they do is slow the boat's drift down, by sitting deep in the water (which may be going in a different direction from the wind, under the influence of tidal streams.

steady boys, steady !
 
the four blade folding grapple is SOME use, but it does not dig in and hold as well as other anchors of similar mass such as CQR, Bruce, Rocna, Fortress, Bugel, and on, and on, and on.

If you are thinking of anchoring seriously, then leave the grapnel ashore.


Start with the Wiki article, here
http://en.wikipedia.org/wiki/Anchor
 
The grapnel is perfect for most anchoring you'll do on the beach - run out the chain, shove the grapnel in the sand/mud/pebbles. The boat won't float away when the tide comes in and you are all getting back on board. I doubt you'll be doing much anchoring at sea and coastal anchoring is usually in abut 3 to 5 meters of water cos you're fishing. Check you've got 10 meters of chain and 10 meters of rope. Then grab a book on powerboating and have a go - lets face it, 90% of anchoring is whilst you're stopped for lunch and you're not going to be spending a night at anchor.
 
Yes, we've no intention of spending the night on the anchor. It's more as you say for coastal anchoring, so we can not drift while we turn the engine off and read, chat, or just relax.

My concern was about being just offshore and not knowing what the depth of the water was and chucking the anchor over and not really knowing what to expect from there, especially if the anchor didn't appear to hit the bottom.
 
Fit a depth sounder to your boat.

Learn about tides/tidal range - especially in your chosen anchoring area.

Make sure you have plenty of 'scope' when you anchor, including a decent length of chain - not just rope. The weight of the chain helps keep the anchor in the correct position to get a good amount of purchase on the sea bed.

The anchor will prove useless unless it has a good grip on the sea bed. It's this grip that holds the boat in position against the tide/wind.

Read some online articles on anchoring - as already supplied on this thread.
 
bung a depth sounder on your boat. you can get them for forty quid on ebay-you'll know what depth of water you're in, for anchoring purposes-and will hopefully stop you clouting the bottom at low tide!
you'll get your money back the first time you don't damage your prop /forums/images/graemlins/smile.gif
 
You will find some useful advice at http://www.fortressanchors.com/safe_anchoring.html
Doesn't mean you have to use a fortress anchor, although there are many who would recommend them. Some anchors are better for mud, others for sand. Many don't like a weedy bottoms. Choosing an appropriate chain/rope combination is as important as choosing the anchor itself. Finally, rope with a lead core for the "wet" end is becoming popular.
 
Think of an anchor as a hook that only works if it is dug into the sea bed and being pulled horizontally, rather that a weight which it is not.

An anchor must be "set", you can't just chuck it over the side, pile a heap on chain on top of it and expect it to hold, you've got to dig it in.

The "scope" of an anchor works best when 5 to 7 times the depth depending on conditions. Don't forget to allow for the the rise and fall of the tide, and the effect of tidal stream reversal on your swinging arc.
 
If you have no idea what the depth of the water is going to be, it sounds as though you are not using any kind of chart. You only need a modest amount of training to get out on the water, but a basic appreciation of a nautical chart is really an absolute minimum.
 
Presumably the PB1 trainer man showed you a chart and roughly how to use it.

To simplify all from above. Let the anchor down, till you feel bottom. Then you need about three times as much spare. If not, go some where else. Your only doing it for lunch stops, if the boat moves, it's not the end of the world. If it moves to much. More chain and maybe better anchor. Though not convinced type of anchor makes much difference. Chain does.
 
Spend £60 and join the R.N.L.I. "Offshore". You can order a "Sea Safety" CD rom that gives information on anchoring, winds, tides, engines, lifejackets, flares etc. etc. Plus all the previous advice about charts etc. You can also get a "Sea Safety" check that will cost you literally tea & biscuits. This is a check on your boat, your equipment and your knowledge of the sea. It is not "Pass or Fail", you are given very good advice, usually from a good old "sea dog" who will answer all your questions I had one last year and learned a hell of a lot more than ropes and charts!! Far too much to list here!!! Good luck and happy sailing!
 
Chart, tide table & compass plus marked lead line will allow you to work out where you are and current/ likely depth of water. The cost could be under 30 quid total. You should not be out there if you can't find out where you are & don't know what hazards there are under the water.

Grapnel is fine for beach use & lunch stops, or even for fishing. But if over a wreck you will risk loosing any anchor without a trip line from the "wrong" end to release it from any potential snags.
 
That is all very well for you to say but you already have the experience and know how to use those items... it sounds like he doesn't. Just spending that £30 probably won't do him much good unless he gets some training in how to use them.

It is all very well to say he shouldn't be out there if he can't find out where you are etc but that is not what the law suggests... there is no licencing requirement nor any training requirement so why shouldn't he be out there? According to the law he has every right to be out there and in a separate thread the vast majority of people would seem to agree!
 
Get on to a RYA basic safety and navigation 2 day course - this will teach you what you need to know to keep yourself and others safe. It has been designed specifically for small boat users like yourself. It will also help all of us to keep the licensing lobby at bay! Call the RYA or any Sea School for advice on the course. Your honestly put question shows that you really need direct and practical advice and a bit of training. /forums/images/graemlins/cool.gif
 
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