Dragging Anchor

mvweebles said:

Sounds like you did the only thing you could do - use the engine(s) to relieve pressure on the anchor. Once the anchor cuts loose, adding more scope is not likely to halt the drift. Dropping a second anchor was probably a mistake - no way it could set, and more likely to foul something important and prevent you from getting underway. Don't do that next time...


Peter

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Covers it nicely, though I would have tried increasing rode after taking the load off it with engines. I suppose you could have tried a retrieve and reset, but tough at night in 50 knots. Prevention beats cure, but that`s not the subject. There are certainly lessons in it too, one is anchor replacement you are already following, the other is appropriate rode to cover exigencies. I hope it ended ok, experiences like that can sear into memory.

Haven’t heard back from the OP. Not that this isn’t a good discussion, but I hate it when we never hear back on this type of thread.
Peter makes a good point, how do you firmly set a cqr in soft mud???

Bmarler said:

Haven’t heard back from the OP. Not that this isn’t a good discussion, but I hate it when we never hear back on this type of thread.
Peter makes a good point, how do you firmly set a cqr in soft mud???

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Don't worry, I'm reading and learning, so even if the OP has gone radio silent, it's not going to waste. It's a good topic for me.

I had a cqr and drug in every blow. Changed to a Fortress this season.
The storm that came up the east coast 2 weeks ago. We were on our 2 week vacation cruising long island sound to Martha's vineyard. We were in oyster bay for the storm, 12 hours of 38knt sustained winds. 70000lb boat with fair windage. Really sails on the hook. Full chain. Held very well and was a little stubborn getting out of the mud. The picture is the track mark from the storm. I figure due to it burying itself , we moved approx. 50'

Solo_Nomad said:

I was recently anchored in a decently protected Cove. I had about 75 ft of chain out on a 35 lb CQR that was firmly set in soft mud. My boat is about 28,000 lb dry, more like 30,000 lb fully loaded; fuel, water, provisions, etc.

The second night an unforcast storm came through the area. I think we were in the center of it because we got winds gusting to 50+ mph with sustained winds in the high 30s to mid-40s. The anchor held at first; then it just let go.

Please don't discuss the CQR anchor; I'm replacing it and I'm not trying to start an anchor discussion.

Also, I'm not a noob I've been through storms at anchor. However, this was my first anchor drag. An early thought, as it became apparent that the storm was intensifying, was to start the engines to hold the boat in position, but things happened very fast after those initial seconds.

My question is: what are you doing during a storm like what we experienced? We were awake, I was at the helm station, the secondary anchor was deployed, but would not set. What do you do?

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1. Agree with others here: Depth is missing component to comment on this.
2. What do I do? In storm or heavy current I put out a second anchor "V" configuration, and increase scope ratio. 5:1 minimum in most any situation.

Most people incorrectly determine scope. The propper way is to first determine the distance from the bow roller to the bottom. NOT from the surface to the bottom OR from the transducer to the bottom. During a storm with all chain rode you should have at least 7:1 scope (it's debatable if more scope past 7:1 is beneficial).

So, if you have 5 feet of water under your keel, and your draft is 4 feet, and it's 5 feet from the water line to the bow roller, you should have (5+4+5) x 7 = 98 feet of chain deployed.

Soft mud is difficult for most anchors unless you've been anchored for days and the anchor is burried deep in the mud.

Unless you were only in 15 feet deep water you didn’t have enough chai out the proper scope for anchoring is 5 times the depth for anchoring and if it is windy even more and you can also change your scope with a anchor snubber

Woodlord made my point. Most people don't know how to calculate scope.

As other have indicated, your anchor is way too small for your boat. Don't trust anchor guides that suggest anchor size by length of boat. Additionally, if you have a flybridge add another 10 lbs because your vessel is catching a lot of wind. On my previous boat, a Catalina Morgan 45 CC with a dodger and rigid bimini I had an 80 anchor and 300 ft of 3/8" chain. I slept like a baby.

Secondly, what size chain do you have? For a boat with that much displacement 3/8" is minimum size.

Thrid, always check scope at high tide (here in the PNW tidal swings are >12 ft. 3:1 for a lunch hook, 5:1 for a protected anchorage, more for bad weather (watch your barometer!).

Fourth, always use a 3 strand bridle or snubber of at least 30 ft in length. This gives some spring action because of the stretch under load of 3-strand, and also helps with the anchor chain catenary.

Solo_Nomad said:

I was recently anchored in a decently protected Cove. I had about 75 ft of chain out on a 35 lb CQR that was firmly set in soft mud. My boat is about 28,000 lb dry, more like 30,000 lb fully loaded; fuel, water, provisions, etc.

The second night an unforcast storm came through the area. I think we were in the center of it because we got winds gusting to 50+ mph with sustained winds in the high 30s to mid-40s. The anchor held at first; then it just let go.

Please don't discuss the CQR anchor; I'm replacing it and I'm not trying to start an anchor discussion.

Also, I'm not a noob I've been through storms at anchor. However, this was my first anchor drag. An early thought, as it became apparent that the storm was intensifying, was to start the engines to hold the boat in position, but things happened very fast after those initial seconds.

My question is: what are you doing during a storm like what we experienced? We were awake, I was at the helm station, the secondary anchor was deployed, but would not set. What do you do?

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I had the same thing happen in Eagle Harbor on Bainbridge Island, WA. No high winds forecasted. Went home with only about 4-5:1 scope out. Tight fit where I was at, because so many boats. Bruce anchor about 30 lbs on a 37 foot Hershine Trawler. I had 200' of 5/16" chain but could only put out about 75' of chain at about 20 feet depth on mid tide. Came back next day and found the boat fraternizing with the ferry terminal. Moved the boat out to 36 feet and put out all 200' of chain. Never had a problem again. Also set up an emergency rig for two anchors one tied to main anchor at the factory pre drilled hole with 25 feet spacing between the two anchors. Have not used it yet but may get into it in Alaska because so many deep anchorages there. Also added 300' of 3/4" double braid nylon to end of chain "just in case I have to anchor in 60 or 80 feet of water with wind". My Bruce holds the boat well if there is enough chain/rode out, but taking no chances. Also have a Danforth 40 backup. Good site for double anchoring if you are not familiar with it at this link... How to Double-Anchor a Boat - Boatsetter.

liquidsands said:

I had the same thing happen in Eagle Harbor on Bainbridge Island, WA. No high winds forecasted. Went home with only about 4-5:1 scope out. Tight fit where I was at, because so many boats. Bruce anchor about 30 lbs on a 37 foot Hershine Trawler. I had 200' of 5/16" chain but could only put out about 75' of chain at about 20 feet depth on mid tide. Came back next day and found the boat fraternizing with the ferry terminal. Moved the boat out to 36 feet and put out all 200' of chain. Never had a problem again. Also set up an emergency rig for two anchors one tied to main anchor at the factory pre drilled hole with 25 feet spacing between the two anchors. Have not used it yet but may get into it in Alaska because so many deep anchorages there. Also added 300' of 3/4" double braid nylon to end of chain "just in case I have to anchor in 60 or 80 feet of water with wind". My Bruce holds the boat well if there is enough chain/rode out, but taking no chances. Also have a Danforth 40 backup. Good site for double anchoring if you are not familiar with it at this link... How to Double-Anchor a Boat - Boatsetter.

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Also bumped up to a 40# Bruce for the main and kept the 30 as a spare.

I refuse to get dragged into another anchor discussion…

Soooo, I hated my CQR and forced it onto a friend who didn’t want it either. Of the old school anchors, I’m okay with the Danforth and Bruce styles.

OP mentioned dropping a second anchor, which I would avoid at all costs. High winds. Whipping and swinging about. A recipe for disaster.

Mako said:

Soooo, I hated my CQR and forced it onto a friend who didn’t want it either. Of the old school anchors, I’m okay with the Danforth and Bruce styles.

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The Danforth is kinda in its own category in my mind. For the situations where they work well, they work very well (well enough to say that pretty much every boat should have a Danforth or Fortress on board somewhere). But I wouldn't want one as a primary anchor, as their performance just isn't well rounded enough.

Lots of info and opinions here on this thread. I stopped reading after 15 posts, lol.
I don't think anybody mentioned a catenary device. A weight that is lowered along the anchor rode to add weight to the "system" to keep the anchor shank DOWN. Kettlebells or a dive belt have worked well for me. Dragging can occur with a wind shift also and the weight of the rode will have no impact. Resetting is all on the anchor type. Keep in mind that storms are cyclonic and the wind will shift during the event. Freeboard does have impact also. FWIW, I am on a 41' Trawler with a Rocna 25 weighing 55 lbs and 300' of 5/16 BBB chain.

TJM said:

Lots of info and opinions here on this thread. I stopped reading after 15 posts, lol.
I don't think anybody mentioned a catenary device. A weight that is lowered along the anchor rode to add weight to the "system" to keep the anchor shank DOWN. Kettlebells or a dive belt have worked well for me. Dragging can occur with a wind shift also and the weight of the rode will have no impact. Resetting is all on the anchor type. Keep in mind that storms are cyclonic and the wind will shift during the event. Freeboard does have impact also. FWIW, I am on a 41' Trawler with a Rocna 25 weighing 55 lbs and 300' of 5/16 BBB chain.

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A kellet is an absolute waste of time for holding power. There are some situations where they may be helpful, but it's rare. Going 10 lbs larger on the anchor will gain you far more than even a 50 lb kellet will in terms of holding, as unless you're in very deep water with tons of chain out, there will always be a point where the chain is pulled close enough to straight that you have no useful catenary left. A kellet will only delay that point a few kts at best in terms of wind speed.

A lot of discussion, but not any feedback from the OP despite many unanswered questions.

-> Boat weight is defined, but not length (many anchors are sized by length)

-> Lewmar CQR lists the 35LB CQR for around 38 - 55 foot boats. IMHO that seems like a large range and way too small.

-> Rocna suggestions are based on a combination of length and eight. for a 30,000 lb boat

33 ft = 20kb (44 lbs)
36ft = 25kg (55 lbs)
39ft = 25kg (55lbs)
46ft = 25kg/33kg (72lbs)

-> We have no idea how deep the water was. IMHO most people calculate anchoring depth incorrectly. Most people don't configure an offset, so the depth is depth from transducer which in between 'depth under keel' and 'true depth'. Anchoring depth also includes the height from the water to the bow roller or cleats as well as the difference from current depth to high tide.

Without knowing how deep, what tide, height to bow roller and length of boat, the rest is speculation. My assumption is the reason for dragging was undersized anchor and insufficient scope.

TJM said:

Lots of info and opinions here on this thread. I stopped reading after 15 posts, lol.
I don't think anybody mentioned a catenary device. A weight that is lowered along the anchor rode to add weight to the "system" to keep the anchor shank DOWN. Kettlebells or a dive belt have worked well for me. Dragging can occur with a wind shift also and the weight of the rode will have no impact. Resetting is all on the anchor type. Keep in mind that storms are cyclonic and the wind will shift during the event. Freeboard does have impact also. FWIW, I am on a 41' Trawler with a Rocna 25 weighing 55 lbs and 300' of 5/16 BBB chain.

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It is a good thing that I read all posts or I would have missed yours. You might miss my reply.

Back in the day kellets were popular as lighter anchors and short boat length chains were the norm. THEN, kellets made a difference. Today, most boaters oversize anchors and go longer or all chain.
As I mostly anchor in 50 feet or less, it is all chain for 200 feet. I have not seen my rode above deck. I sleep well.

My, a lot of input and I like that you realize you need a new anchor, and heavier too.
I hope you settle on an original Rocna. On our boat about the same weight, maybe a little heavier we have a Rocna 55# anchor.

Now, presuming you have the right windlass to haul it up, that would be your 1st step.

With your issues you asked what you would do under your circumstances and what I think I would have done, without knowing your location for anchoring is to maneuver so I could reset the anchor, but then the anchor you had had proven it wasn't reliable but then maybe with more scope it would be.

We anchored in a cross over, off the Mississippi in action stage. 8 mph current. Our anchor not only held, it dipped the bow about 6" when she was retrieved. That's the kind of anchor you need.
Good luck

The first thing I replaced on my boat after purchase was the anchor. Defever 48, 60-70k lbs had a 60 cqr(undersized for the boat and I'm not a big fan of cqrs) and it dragged twice in the first 2 weeks underway. I took advantage of a black friday sale and got a 105lb Mantus, which is only their cruising rated anchor not storm rated, and haven't drug since.

I only have 200' of chain, but since I boat on the east coast I'm usually anchoring in fairly shallow water. I typically anchor at 5:1 scope(and yes, that's from the bow roller) in normal conditions and bump it up to at least 7:1 if it is or is expected to get sporty.

If I were to drag, and I had room, I would most likely let out additional scope as I believe the Mantus to be quite good at resetting.

Would approach this with somewhat different concerns.
Motoring with an anchor down takes a fine touch. He is already dragging. He is in soft mud. Even the next gens need to settle through the soft mud and get to firmer mud to hold. I place a pin where the anchor was dropped every time we anchor. Using that I’d head to the anchor so there’s no strain on the rode and wait. The longer the better. Then slowly reduce revs and drift back. Use the bow/stern thrusters to keep heading into the wind. Supplementing the rudder. Yes while doing so add scope. If the anchor drags a second time up it comes altogether. Then head out far enough to have sea room. Head int the wind and waves at the slowest speed than gives me steerage.
Things I do before picking an anchorage. Look again at predicted weather. Look at nearby possible anchorages and which wind wave directions they offer protection. I have moved before dragging when I was worried. Even if it meant not reanchoring but a better place for wind/wave protection while sitting under power.
I don’t want some one messing on the foredeck in a blow. It’s dangerous. If the snubbers need to come off we’re leaving. One shot at reanchoring where we are. That’s it.
Been very conservative. In soft mud always let out more rode. Have only used nextgen since they came out. Rocna, current Vulcan, prior Spade. Do carry a Fortress but if I didn’t put it out in the first place I’m not switching ground tackle in a blow. Again don’t want anyone on the foredeck longer than absolutely necessary.
Never understood two anchors except on initial drop. Again being on the foredeck is dangerous.
When using the engine do have concerns if you’re not careful you are repetitively loading and unloading the anchor. That’s a good way to work it out of a set.
We’ve only dragged on initial attempts and once in Chesapeake in soft mud but just a fresh breeze during the day (no drama). That’s in 35y of frequent anchoring. Reason is I’m a wimp. Drives the bride crazy I’m so picky about this.

Would note the Rocna was lousy in mud soup. Here a fortress was our preferred option.

Bmarler said:

Haven’t heard back from the OP. Not that this isn’t a good discussion, but I hate it when we never hear back on this type of thread.
Peter makes a good point, how do you firmly set a cqr in soft mud???

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Thank you all for the comments. I was not trying to initiate an anchor or anchoring discussion. I want(ed) to know what others do when the anchor is dragging. Not prevention, it's happening: what are you doing to save your boat?

Solo_Nomad said:

Thank you all for the comments. I was not trying to initiate an anchor or anchoring discussion. I want(ed) to know what others do when the anchor is dragging. Not prevention, it's happening: what are you doing to save your boat?

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What would I do? In the short term I'd re-anchor or motor to relieve pressure. Tossing out a second anchor and hoping it would set is a Hail Mary and will complicate retrieval and moving the boat. Since you've presumably survived the dragging intact and not looking for realtime advice, the real question is how to avoid dragging in the future which depends on why you dragged in the first place which is why the questions left unanswered were important.

Frankly, the way the question posed was difficult. You didn't have time to motor into the conditions but had time to set a second anchor. And I still wonder how you got a CQR to set in soft mud as described. I know you want a narrow answer based on the fact that you are "not a noob." But some of the description begs more questions than answers to understand.

Peter

Solo_Nomad said:

Thank you all for the comments. I was not trying to initiate an anchor or anchoring discussion. I want(ed) to know what others do when the anchor is dragging. Not prevention, it's happening: what are you doing to save your boat?

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Part of the equation is 'reaction', the majority is 'preparation'. What I do when I see a severe thunderstorm move in is.... lay out more scope. I extend the length of my chain snubbers. I open all the curtains, remove the window covers at the lower helm and get both helms ready to run.

In the thick of the thunderstorm my engine is running. electronics are on. Rain jackets are out.

If I were to start dragging, I'd pick up the anchor and re-set. However, good luck rounding up into 55 mph winds in a tight anchorage.

Solo_Nomad said:

Thank you all for the comments. I was not trying to initiate an anchor or anchoring discussion. I want(ed) to know what others do when the anchor is dragging. Not prevention, it's happening: what are you doing to save your boat?

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Not sure I understand this question... is there another parameter you're considering, like your engine won't start or something? Certainly wouldn't throw out a 2nd anchor unless you're staring down at rocks off your butt and your engine won't start and you have no other choice.

Anyway, the obvious answer is you start your engine, power up to your anchor while retrieving it, then reset. 50 knots is a strong wind but your engine has enough power to make headway. You'll have challenges with your bow falling off in those strong winds, and a bowthruster will be next to useless to help, but you can work through this challenge easy enough. You're heart will be beating through your chest, that's for sure.

rslifkin said:

A kellet is an absolute waste of time for holding power. There are some situations where they may be helpful, but it's rare. Going 10 lbs larger on the anchor will gain you far more than even a 50 lb kellet will in terms of holding, as unless you're in very deep water with tons of chain out, there will always be a point where the chain is pulled close enough to straight that you have no useful catenary left. A kellet will only delay that point a few kts at best in terms of wind speed.

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I'd agree with the various previous comments that kellets aren't today's answer. I think they went out of style with "lunch hooks."

I bet if you asked @NomadWilly he'd say (and I do too) that the best solution would be 3 feet of 1" stud link chain attached to your anchor as a leader. I'd even bet that in a hurricane the first link attached to the anchor would remain perfectly horizontal. Unfortunately most boats don't have the space between roller and windlass for this setup.

I’m just returning from a trip to Desolation Sound. Anchored in Buccaneer Bay on the way up. Probably 20 to 25 kts wind from the south which was ok because the U Shape of the anchorage was in my favor. Didn’t check Windy app which was a mistake. Around 0300 the wind shifted 180 and rollers came in from the north. Bounced the boat around and although we weren’t dragging yet, it felt like there was the possibility. The boat was jerking around with the rollers coming at us.
Couldn’t sleep under those conditions and nothing but bigger water going north ahead of us, pulled up anchor and motored into the wind and 3’ seas.
It was sure nice to be in Lund a bit earlier than planned.
Heard stories of others that were less fortunate with the wind shift

jp

Well it looks like the O’dark 30 wind shift, now from the North in Buccaneer Bay claims yet another victim. Even trying to hide behind the Surrey Islands is futile.

Buccaneer is a great day stop but Pender Harbour, 1 hour to the North is the best place that's close, to get a good nights sleep on the hook.

Hope you had a great trip.

Thanks for the tip Luna. It was suggested as a good place to stop by a local guy from Pender Harbor that I met at Princess Louisa last year. Way to prank the foreign visitor.
Anyway we survived and had a memorable trip. Always learning new lessons.
jp

Didn’t check Windy app which was a mistake.

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Curious if windy or GOV forecasted this 180 shift in wind or if it is a freak event.
Lately, forecasts are not similar to actuals on windy in gulf islands, climate change?