I just dragged anchor for the first time in my life. Clueless!

[2hullvenus]

I'm curious what the theories are on this.

I just dragged anchor for the first time in my life of boating... that's over 25 years now, sitting out a couple tropical storms, anchoring everywhere from Canada to Venezuela. Thousands of days/nights at anchor in every condition imaginable.

I've slept at anchor the majority of my life in the past 10 years as well.

Here's what happened:

The setup

10' of water at high tide
50' catamaran weighing in at 6 tons currently.
80 lbs Manson Supreme anchor, real one
100' of 5/16th HT Acco chain deployed
A pair of 20' 3/4" rope snubbers hooked to the chain and taking the whole load to my bow cleats
Inside the 20' snubber lines are also those rubber line shock absorbers
20 knot winds, flat water, reversing tidal current
Anchor float

Odd discoveries

Came out to look at the view and saw one of the rubber line shock absorbers in the snubber lines was ripped in half. Both ends still attached.

Both chain hooks were in the water dangling, not attached to the chain. This happens a lot, so I now tie them to the chain so they can't slip. Probably tied them poorly.

Chain taking full load.

Boat was right on top of anchor float. A very odd thing given the strong current and wind that were going in the same direction!

What I did

Pulled in 20' of chain to re-attach and re tie the snubber lines.

I've got the snubbers on, I'm intently snaking my chainhook tie down line that keeps the chain hooks from falling off very carefully, noticing nothing around me.

I hear a horn blast. I look around and I'm going under a bridge!!!

Swift current and wind sent me there very quickly.

So i ran around like a mad man. Lowered outboard, started it, turned on fuel system, etc... within seconds of hitting the bridge.

Gained enough control to go under the bridge without touching it in any way... completely sideways!!! Port first instead of bow first!

Whew!

On the other side, i started cranking in the anchor, expecting to find my brand new 80lbs Manson Supreme gone from the end of the chain.

It was there!

100' of chain and an 80lbs mansion supreme dragged all the way to/through a bridge without catching on anything!!!



How is any of this even possible??

Does anyone have theories?

Mine is that the wind/current reversals over the past few days here got my own chain fouled around the anchor, which was why I was right over the anchor (in windy conditions with same direction current). Then, pulling in 20' was like reducing myself down to 1:1 scope because everything was tangled up. Still, I don't see how I went a quarter of a mile and under a bridge without the 100' of chain and 80' Manson Supreme catching anything.

It came up normally once I got a moment to pull it in after having passed under the bridge.

No tangles, all gear fine.

I'm sitting on it again now at the same 10:1 scope and all is well.

[2hullvenus]

Additionally, it's an urban area where there is no doubt some junk on the seabed.

Still.. I'm lost...

[Mark1977]

Scary stuff, sounds like the anchor was fouled. Probably came out as you hoisted it.
25 years of boating and never drug an anchor?? I would say you're doing good...

Sent from my Nexus 5 using Cruisers Sailing Forum mobile app

[Captain Bill]

Anchor float fouled holding the anchor off the bottom?

[2hullvenus]

Originally Posted by Mark1977

Scary stuff, sounds like the anchor was fouled. Probably came out as you hoisted it.
25 years of boating and never drug an anchor?? I would say you're doing good...

Sent from my Nexus 5 using Cruisers Sailing Forum mobile app

Yeah, this is my first time.

Only other type of drag was a Delta kind of slowly oozing its way through some mud in a tropical storm. Moved a couple boat lengths in 24 hours. I didn't really count that as a real drag.

I'd like to understand how this could have happened.

I've anchored in reversing tidal currents much stronger with a delta and no issues.

[Cheechako]

Well...... you've been awfully lucky until now! There is no perfect solution.
-Some anchors are better in some bottoms. (Rock vs clay vs sand vs mud)
-Some bottoms are not good with any anchors. (shallow mud or sand over hard pan)
-Most anchors are not good in reversing wind direction. (and tests do not do this, so you have no idea) Often the ones that do hold just never pulled out and held backwards.
- Some anchors love to stay set but just keep moving/plowing thru some bottoms (Bruce/sand)

[Kenomac]

Stuff happens, no anchor works 100% every time. Despite doing everything correct, we dragged last season up onto the beach using our trustworthy Ultra 45kg, fortunately.... no damage at all.

You'd be surprised at all the junk and rock on the bottom of anchorages. Sounds to me like you had an excellent run going.

Last year we'd just sit anchored in the middle of Soller harbor on Mallorca watching the steady parade of boats trying unsuccessfully to anchor on the west side of the harbor. Each time thinking they had it just right, in the perfect spot; then they'd drag, move, then another boat would come and do the same. Better than watching TV.

My guess... you snagged onto something which gave you the false impression you were properly dug in. Some of the pull on the anchor released, your anchor tipped onto its side leaving just the weight of the anchor and chain to hold you in place. When you shortened scope, that was just enough reduced holding power from the reduced weight to begin your adventure.

Welcome to the club. I dive on my anchor as much as possible, I'm shocked by what I see many times after thinking I'd done a perfect set. Anchor just sitting on top of a rock, sometimes grabbing onto WWII junk... You name it.

[Tetepare]

You never really know what you're anchored on. A few years ago a boat dragged and when they brought up the anchor attached to it was a dinghy and outboard that went missing more than a decade earlier.

[akprb]

Well a great story for sure! I like your theory. I also love my anchor alarm on the gps :-) (and now the "drag queen" app on the phone)

You had a good run and glad no damage!

[Sandero]

You were lucky for the past 25 years and should have learned some more anchoring ;-)... sounds like your anchor got fouled and wasn't able to do much.

[BambooSailor]

If you look at the shape of your anchor, it is concave only in one direction. (That's why I do not like it.) At certain deployment angle, this anchor provides very little resistance/holding power. Maybe you were just unlucky to hit this "sweet spot"?

[Don C L]

Better to be lucky than good! But seriously, all these years and it's the first time you've dragged is not too bad. I can think of many scenarios. First how deep was it? For you to be over the anchor buoy is very odd, how much line was on it? How big is the buoy? Does it have 80lbs of buoyancy (could it have lifted the anchor?) Could you have dropped 5 or 10 feet of chain on top of the anchor that could have formed a fouling lump? How long have you been using this particular anchor? You are on one anchor so a current and/or wind shift could have swung the chain around the anchor to pull it out? (I am sure you have probably thought of all these already.) I have no experience with the Manson anchor but there is the famous "photos of anchors setting" thread here to check out! If the anchor had fouled on trash it seems like it might have shown something of that. Where I am we almost always have a current and/or wind shift at night so I would not sleep well with one anchor down, but that is me. I always have 2 down, bow and stern or Bahamian style. So far the only time I dragged was with a 45lb CQR on a Downeast 38. It was 3 am and by the time I got the mess sorted out in the howling wind I couldn't really check, but I think it may have grabbed some kelp when I initially set it. It dragged about 50 feet before setting again. I had a 20 lb Danforth on the stern which ended up holding me too. I use Danforths still. I am probably the last one on the planet, but I am sticking with a design that has yet to let me down!

edit, oh, I see you were in 10 feet of water, is that right? One other possibility, the anchor fell just up from a diagonally laid cable and instead of setting the anchor dragged along the cable and slipped off of it when you pulled it up. That may be a bit if a stretch but I can kind of picture it happening.

[Jim Cate]

edit, oh, I see you were in 10 feet of water, is that right? One other possibility, the anchor fell just up from a diagonally laid cable and instead of setting the anchor dragged along the cable and slipped off of it when you pulled it up. That may be a bit if a stretch but I can kind of picture it happening.

Well, from personal experience, a Supreme will NOT "slip off" when fouled on a cable... oohhh noooo! Quite the opposite, in fact. You need not ask how I know this.

Jim

[Don C L]

Originally Posted by Jim Cate

Well, from personal experience, a Supreme will NOT "slip off" when fouled on a cable... oohhh noooo! Quite the opposite, in fact. You need not ask how I know this.

Jim

Yeah that was a long shot, AND how do you know this???

[JPA Cate]

Unless you buried the anchor's shank, too, I'd think the changes from tide cycling caused a wrap round the shank, and out she came? It is prudent in those wind against tide, tide cycling anchorages, to re-set the anchor each day. It only lessens the chance of dragging.

Also, 10 ft. is a little shallow, but thus spoke the 2.2 m draft mono owner. Your 60 ft. cat probably has more windage than your previous boat, perhaps that's the rub--not heavy enough chain for the boat? I'd ask similar size cat owners about that. however, assuming that anchor and chain are appropriate, then we come to the broken rubber shock absorber and the chain hooks coming agley.

That sounds like a huge sudden load. Possibly your gear experienced a huge wake, or a serious wind puff, that snapped the one, and broke your lashings on the other? [consider soft shackles for attatching snubber to chain.]

Finally, an outboard for a 60 ft. yacht? Really? Not common on the larger cats we see, and none of the international ones. ymmv

Ann