Is there such a thing as "too much scope?"

[Kings Gambit]

Well, we were anchored out at Santa Cruz Island on a different trip than the one mentioned earlier in the thread on etiquette. Once again, we're alone on a single hook when a second boat, an Ericson 32 with a guy and his wife, arrives, makes its way to windward of us, anchors near that same reef, then deploys a stern hook w/o any consideration of us. However, this time we're a little further back and on shorter scope--only 75 ft, so I don't get as bothered about it. Another boat comes in, a new 37-ft Sun Odyssey, circles me asking if I'm planning to put out a stern anchor saying "b/c that's what's generally done in here." I said I wasn't planning to, BUT (giving in here I suppose) that I would if the situation started to require it. Everything is fine. Later, another boat comes in, an older Catalina 30 I believe, whereupon I sat amazed as I watched the guy deploy what looked like over 250' of 3/8" chain on one end (bow), and then about that much in nylon rode on off the stern, in what was probably only 30 ft of water. This was on an afternoon when the overnight forecast was "winds variable 10 kt or less after midnight, wind waves 2 ft or less..." Where are we with all of this? There's a problem of perception here in my view. Excessive scope would be needed if you're facing 4' - 6' rollers on your bow--but in calm conditions?

 

[MattM83]

when things go bump in the night it may just be your anchor neighbour whos anchor is at the other side of the bay. that amount definately seems excessive. putting too much out always increases the odds of snagging on something.

did they atleast put out fenders?

 

[Stu Jackson]

KG, I've been doing some research on this over on cruisersforum. Here's part of one post, that applies to both this and your earlier one.

What to "do about it" has always been the subject of much discussion.

Under Admiralty Law there are rules:

Quote:
Decision No. 124-5861 (1956) in U.S. Admiralty case law states: “A vessel shall be found at fault if it . . . anchors so close to another vessel as to foul her when swinging . . . (and/or) fails to shift anchorage when dragging dangerously close to another anchored vessel.
Furthermore, the vessel that anchored first SHALL warn the one who anchored last that the berth chosen will foul the former’s berth.

 

[Stu Jackson]

KG,

There's some good stuff here:

http://www.cruisersforum.com/forums/f2/anchorage-etiquette-53094.html

and here: http://www.cruisersforum.com/forums/f118/the-herding-instinct-39502.html

which includes:


There actually is case law regarding anchoring too close to another boat.

Decision No. 124-5861 (1956) in U.S. Admiralty case law states: “A vessel shall be found at fault if it anchors so close to another vessel as to foul her when swinging (and/or) fails to shift anchorage when being dangerously close to another anchored vessel. Furthermore, the vessel that anchored first shall warn the one who anchored last that the berth chosen will foul the former’s berth.”Note, however, that if you start to drag anchor and/or threaten to collide with another vessel, it doesn’t matter that you anchored first. A dragging boat must take immediate action to avoid collision and find a new berth.

 

[higgs]

I have heard 7:1 is ideal and in 30 ft that is 210 of rode. In the conditions you describe, I personally would not do 7:1. In light variable winds I like a stern anchor with maybe 2:1. Enough to hold me in place , but if the wind does kicks up I want the stern anchor to break so that I head bow to wind.

 

[Stu Jackson]

Techniques and proper gear are also required. The link I provided above has a lot of fun stuff worth reading.

One reply is this one that I admire:

I can't believe I'm reading this exchange here.

Safe boating rules/conventions are not arbitrarily cooked up by lawyers or committees. They have evolved over literally 100s and 100s and 100s of years of real Sailors figuring what actually works.

 

[capta]

Four years back, we were anchored between Petit Rameau and Petit Bateau islands in the Tobago Cays for Christmas.
Being Christmas time, the Christmas Winds were outdoing themselves with steady winds from 25 to 30 knots for weeks on end (hey, Christmas is winter time in the Caribbean too, you know). We sat well on 110 feet of chain (with a snub) in 10 feet of water, barely swinging at all. Then the wind died for a day and our swinging room increased from a few dozen feet, bow into very strong winds, to almost 300 feet as the tide finally overpowered the wind for the first time in weeks.
The next day the wind came back (and stayed until late April and folks don't believe in climate change?) so I was very happy for all that scope, again. It really was overdoing things a bit 10:1 scope in a good, all sand bottom, so I'd have to say that yes one can have too much scope out. Especially if others would like to share an anchorage with you.

 

[JamesG161]

Scope of the anchor is a bit of guessing what the weather and the effects of near by land.

Without going into much detail...

We anchored between two islands on forecast 10 knot winds. We anchored on the leeward side of the 1st island to be in smooth seas even though the winds were forecasted to change from West to North we should have not had any significant waves.

We set our anchor at 5 scope in 12 feet of water and set the drift alarm. zzzzzzzz zzzz zzzz

At 1am we were jolted with the bow slamming down from the start of 6'-8' waves. Anchor held well. At first we thought collision.

But here is the point...

The winds shifted from west to NE and from 10 to 20 knots causing waves to be "funneled" and amplified between the islands (land effects).

So the length of our boat (43'), the frequency of the waves, and depth of water combined with an out of forecast weather for a wild ride till daylight where we could weigh anchor without fear of a night time MOB.

Our anchor tension "eye hook" bent straight with waves lifting our 13 ton boat.

A 7 scope would have had little affects on the pounding we took.

So it is obvious that there is more to safe anchoring than scope.

Jim...

PS: We were happy the anchor held (right scope) and didn't let us drift into the island.

 

[thinwater]

Our anchor tension "eye hook" bent straight with waves lifting our 13 ton boat.

A 7 scope would have had little affects on the pounding we took.

So it is obvious that there is more to safe anchoring than scope.

Jim...

PS: We were happy the anchor held (right scope) and didn't let us drift into the island.

You need to add a nice long (30-40') snubber to your tool box. The chain snatching tight is brutal.

 

[JamesG161]

You need to add a nice long (30-40') snubber to your tool box. The chain snatching tight is brutal.

Brutal was an understatement!

I was proud our boat took it in stride. Made me more confident in the boat structure.

I think you meant 30 or 40 inches and not feet.

Heck, with the shallow waters here on Mississippi gulf coast we don't even let out the anchor to reach the rode. In the Mississippi Sound, about 12 feet, south of the barrier islands more like 30-60 feet.

But your idea got me thinking about adding something it to the tensioner.
I don't like full boat impact on the gypsy. I would rather lose a $15 hook than a $3500 windlass.
Thanks for the feedback...
Jim...

PS:The Admiral and I didn't fair a well as the boat did. We motored to the "new" leeward island side anchored and slept to noon in calm water.:zzz:

 

[capta]

Brutal was an understatement!

I was proud our boat took it in stride. Made me more confident in the boat structure.

I think you meant 30 or 40 inches and not feet.

Heck, with the shallow waters here on Mississippi gulf coast we don't even let out the anchor to reach the rode. In the Mississippi Sound, about 12 feet, south of the barrier islands more like 30-60 feet.

But your idea got me thinking about adding something it to the tensioner.
I don't like full boat impact on the gypsy. I would rather lose a $15 hook than a $3500 windlass.
Thanks for the feedback...
Jim...

PS:The Admiral and I didn't fair a well as the boat did. We motored to the "new" leeward island side anchored and slept to noon in calm water.:zzz:

If you read the manual for your windlass it should specifically say that you should NEVER place the anchor strain on the windlass; it is NOT designed for that. You are very lucky you got away with that and you should definitely buy a lotto ticket. You need to get the load off the windlass, asap.
30+ feet is not excessive for a snub line in bad weather, especially in any seas at all. Remember, you are not anchoring for the present conditions, but for the worst possible conditions that might occur.

 

[Stu Jackson]

You need to add a nice long (30-40') snubber to your tool box. The chain snatching tight is brutal.

Right!

Here's what a friend of mine does:

A new gen anchor. All 20kg of it with 100ft of chain. The rest of the world can debate all they like. When I pull into a place like Bodega Bay at midnight and the fog is so thick I can't see the jetty 50 feet away to make an entrance, I drop my hook in the rolling ocean swells with the surf crashing (Foster says it's like staying in a cheap Best Western beside the highway), and I sleep. And in the morning I have a windlass to pull the beast up and I wouldn't trade it for anything. (I also wouldn't add more chain - this works perfectly in 25 to 30 feet of water - you let all the chain out and you tie off nylon at the preferred scope and don't bother with snubbers and chain hooks and all that stuff...)

 

[JamesG161]

I NEVER leave the gypsy in direct strain, except when in dropping or weighing of course.

My Hunter boat has 2 reinforced cleats and a through "eye bolt" inside the Anchor closet. The boat came with a chain link double forked SSteel that grabs a single link and connects to the Eyebolt with a smaller chain (see picture). That is what i called the tensioner but should have called snubber, I guess.

One fork snapped and one bent straight so it was inadequate during our 4 hour ordeal. We now have a 5/8" cable and snap hook that will take 15k lbs of impact tension, but no shock adsorbing snubber.

I just did a quick anchor snubber search, which should reduce the impact of anchor strains/shocks in addition to our tensioner/snubber.

http://www.amazon.com/Davis-Instruments-Shockles-Snubber-20-Inch/dp/B00HAOJO3I/ref=sr_1_2?s=sports-and-fitness&ie=UTF8&qid=1441044394&sr=1-2&keywords=anchor+snubber

Which is 20 inches not feet, but I am still in review. This one looks like a Link to Link impact absorber (leaving 6-8 anchor chain lengths slack). I don't expect it to stop the gypsy strain but just impact shock absorber.
Any thoughts?
Jim...

PS: I guess I need resilience/spring and not metal strength.

 

[JamesG161]

sorry i forgot to hit upload for picture on my link.
Jim...

 

[Gunni]

Forget those "shockles" things, they're worthless. That chain grip thing you have was most likely designed to stow your anchor while underway. A nice long length of triple braid nylon rode gives you the kind of stretch and shock-absorption you are looking for. Take it to a cleat, not that eye in your anchor locker.

BTW, scope is for keeping your anchor in the bottom. Not for absorbing snatch loads when you anchor somewhere you really should not anchor.

 

[scotmcpherson]

. I would rather lose a $15 hook than a $3500 windlass.

$15hook?

Where do you buy your stuff? I need to go there.