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All about anchoring at Santa Barbara IslandMarc Hughston01-21-11  05:34 pm
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David Sheriff
Board Administrator
Username: admin

Post Number: 135
Registered: 01-2004
Posted on Friday, July 18, 2008 - 02:40 pm:   Edit Post Print Post

The Danforth gets scary when it might be set in light kelp, but plenty of scope and a light boat help. I anchored 28' La Mouette bow and stern this April in Little Harbor and very slowly dragged my bow anchor along the bottom. In retrospect I must have cut a furrow 30 feet long. I may have just dragged through sand and the large kelp ball I retrieved may have just tangled around the rode. I don't know. Makes me want to take the class again.

I set my bow Danforth in about 15-20 feet fairly close to the reef and then backed 275 feet toward the beach, pausing to set the anchor with full reverse thrust. I was not aware if I had set in kelp or not because none was visible at the surface. I dropped my stern anchor, another Danforth somewhat larger, perhaps 50 feet off the beach in 10 feet of water and worked my way back toward the bow anchor. I ended with about 225 feet of rode off the bow and 50 feet off the stern with the rocks separating Little Harbor from its larger cousin Shark (I believe that's the name) about 150 feet off the port beam. Everything seemed pretty stable, taking bearings off the shore. As night fell we had not moved as far as I could tell. I left just enough slack to accommodate the tide and settled in. A check in the middle of the night at low tide seemed fine.

There was some wind during the night which rocked the boat quite a bit in spite of using a flopper stopper. Julie refers to this as the night of the storm, everything being relative of course. The next morning I had to take in about 10 feet of slack in the rode. I did not think a lot about it at the time as our position had not changed appreciably. The day was good and we spent a quieter night. The next morning there was another 10 feet of slack in the rode. It was apparent that the one or another of the anchors was dragging slowly.

Once prepared to leave, I backed again by hand, letting out the bow and taking up the stern, and retrieved the stern anchor. I should say that I had led the bow rode back to the cockpit and a winch so I could do everything single-handed. I had the engine running as a precaution but the boat is light enough to pull around with one person. There was a little kelp on the stern anchor, most of which had wrapped on the rode as the current carried it past the boat.

While retrieving the bow rode I may have had to center the boat once or twice using the engine in reverse. The boat backs to starboard, which was away from the rocks conveniently. I was also able to steer pretty well in reverse with the engine just a little above idle. I snubbed up on the rode to yaw the boat until it was backing in the right direction and then let out, which was how I got the boat backed up 275 feet in the first place.

Once you retrieve the almost all of the rode and prepare to lift the anchor everything has to happen very smartly. As expected, there was a good ball of kelp on the anchor which I hacked at with all the determination of a man adrift. The anchor was still set to judge by the effort required to dislodge it, although whether it was set in light kelp or not is beyond my experience to judge. I think now that if it is shallow you should expect some growth on the bottom whether it comes all the way to the top or not. Just inside the reef there may have been enough turbulence to keep things torn up. Amazing how we relive every anchoring to squeeze out all the significance that might not have been apparent at the time. I am quite certain that if I had only been anchored on kelp it would not have held.

Given the configuration of the anchor locker on La Mouette, a Danforth is all that will fit. I am saving for a 25 pound Manson Supreme plow which I will have to stow separately. I have also made up my rode with large galvanized threaded-pin shackles and a thimble spliced into the bitter end. I have two 100' rode extensions with thimbles at both ends so that I can get beyond the 275 feet I can carry in the anchor locker. The bitter end of the main rode is shackled to an eye in the anchor locker so I can free it up to shackle on an extension if necessary. I guess I worry about having to anchor in deeper water and worse conditions than what will fit into the anchor locker allows.

Quite a pile of rode accumulates on deck when retrieving by yourself. I have considered retrieving from the cockpit, but I'd rather have the mess on the bow and keep the rode as far away from the prop, keel and rudder as I can. Even with the prop disengaged, all it takes is to get caught on the keel or spade rudder and you cannot risk trying to motor out of trouble.

It takes a bit more thinking-out-the-moves to sail and anchor single-handed, and there are just some things you do not do. But you can tack reasonably well if the tiller doesn't flop around and you can pick up moorings, dock and anchor just fine if conditions are not too severe. You find yourself tacking with the sheet running across the cockpit to the "wrong" winch, and you miss tacks more frequently or you just gybe because it's easier. It may not be as pretty but mostly it works. You make adjustments, like running a line up to pull down the main after getting caught with everything flogging a few times. I also have jacklines and preventers permanently rigged. I've just about worn out my harness/PFD. If sailing is interesting because it keeps your attention focused, then singlehanding is really interesting. At least there is no miscommunication with the crew and there is no problem knowing who is calling the shots. There is no hesitating about reefing because you wonder what the rest of the crew is thinking. At the end of the day it's hard to tell if you are more physically or mentally tired, and you sleep well if fastened to something that will not move.
 

Mark Howe
Moderator
Username: unclemark

Post Number: 379
Registered: 08-2003
Posted on Wednesday, April 23, 2008 - 09:02 am:   Edit Post Print Post

The boat in Mexico was the AlaMode; I use it as an example of a boat dragging a Danforth when it picks up kelp. It ended up on the beach and was burned by Mexican fishermen to get the engines out. The plow worked fine.

The additional forces result when a boat is prevented from weather-vaneing thereby presenting more resistance to wind/ currents. Pegging it on the bow allows it to always point into the direction of push.

In class we talked about the ellipse a boat would describe if using 2onthebow. In Marc's example, if we dropped the 2nd anchor 270ft out with a 250ft rode, the ellipse would be between the two anchors and would not allow the boat beyond that point. The two obstacles would be safe.
This probably requires a diagram; not sure it answers all the questions.
 

Marc Hughston
Moderator
Username: hughston

Post Number: 637
Registered: 03-2003
Posted on Tuesday, April 22, 2008 - 09:39 pm:   Edit Post Print Post

On Anchoring

I don't know the story of the burned boat in Mexico. I'm getting kind of burned on this Anchoring Underfoot thing though, but I'm not done yet. May 7-11 I'm in the the Northern Channel Islands and will try again at Cuyler Harbor at San Miguel, and give you my report. I'm going to have to fail with it a number of times to figure it out.

Next, Mark, why do you say that hanging the anchor underfoot off the stern would create additional forces?

Finally, I think this business about letting out more rode to increase scope, as a suggestion to stop from dragging into boats or other crunch-causing objects really points to the limits of this method and the need to change tactics. You could move and swing from a single hook somewhere else as we did, or perhaps move and go Bahamian or Bow and Stern when well clear of other vessels that are swinging to a single hook.

And no one has mentioned this yet: what if we were anchored underfoot, not moving, and another earlier arrival who was swinging to a single hook swung in to us? Yep, we'd have to move.
 

Mark Howe
Moderator
Username: unclemark

Post Number: 378
Registered: 08-2003
Posted on Tuesday, April 22, 2008 - 09:31 am:   Edit Post Print Post

Great analysis; here is my two cents.

1. The kelp that the Danforth picked up was just as we predicted; same situation as the burned boat in Mexico. This would be a disadvantage of a Danforth anchor used for drudging where there is kelp.
2. Attaching the second anchor to the stern would tend to position the boat so there would be greater forces, whether they be current or wind.
3. Since the coastline is obviously steep, the second anchor would be pulled uphill requiring less scope, but obviously more than the 1 1/2 to one ratio used.

A possible solution would be using a three to one scope for the second anchor and tying it to the bow; this would be the entire 250 foot rode. This would allow the boat to drift back to its original location but avoid the cutter and the trimaran, even if they remained stationary [which they would not; even with all chain boats move a little bit].
Using Anthony's suggestion, the extra scope could be paid out as soon as the crew became aware that the boat was beginning to drudge. The only problem would be reacting before the anchor began collecting kelp.
This example would lend itself to GPS mapping where the actual path of the drifting boat could be seen. The precise moment the second anchor began to drudge there would have been an indication on the drift line.
 

Marc Hughston
Moderator
Username: hughston

Post Number: 636
Registered: 03-2003
Posted on Monday, April 21, 2008 - 11:20 pm:   Edit Post Print Post

I have some additional experience with Anchoring Underfoot to relate from a trip this last weekend. Our vessel for this trip, Betty, is a Catalina 42 with the following ground tackle:
Bow – 270 feet nylon rode with 30 feet of chain, for a total of 300 feet of rode, and a Bruce anchor (20 kg. I think).
Stern – 225 feet of nylon rode with 25 feet of chain for a total of 250 feet of rode, and an appropriately sized Danforth anchor.

Saturday night found us in the Hen Rock portion of White's Cove on Catalina, outside the row of mooring balls, and between a tramp of a trimaran on chain about 150 feet away to port, and a traditional looking cutter with all chain about 100 feet to starboard. Depth where these boats lay was approx 55 feet. We lowered the bow hook even with a line just aft of the sterns we were between and laid 290 feet of rode in the water off the bow as I expected to swing through depths of 60 to 90 feet.

Though we set out bow anchor into the wind with our nose toward shore to the West, we immediately swung to a gentle current pushing us to the right and toward shore and the cutter, against the 2-4 knot breeze. This was a pretty unusual current in my experience at Hen Rock. We backed away from the cutter into deep water and set an anchor “underfoot” off the stern – 130 feet of rode in 90 feet of water. That was at about 7:30 PM. The second anchor did bite showing light strain on the rode, and we stopped moving toward the cutter.

At about 11:00 PM I was reading in my cabin while crew, having finished a card game, went on deck for a look. They immediately called me up as we were now only about 35 feet from the trimaran that had previously been so far off to port. I opted to weigh both anchors and find a new spot. There was a big ball of kelp that came up with the secondary Danforth.

In our new spot we settled about 500 feet off the cliffs just East of Moonstone Beach in 50 feet of water where the ridgeline continues down from the beach and builds up a shallower area than that found a hundred yards on either side. We lay to a current setting East with our bow pointing toward the West End. At 7:00 AM the next morning we lay to a current setting West with our bow pointed toward Avalon.

My conclusions:
1. The anchor underfoot did not limit out swing as I had hoped, perhaps due to picking up the kelp as it dragged and preventing it from setting again.
2. Current will overcome a light breeze in any anchorage and a sailboat will lie to the current in that condition.
3. I like all chain for the rode better than the usual So. Cal. combination of about a boat-length of chain and three-strand nylon for the rest. This would have limited our swing effectively as it did with the other two boats we found ourselves near.

Discussion? Comments?
 

Mark Howe
Moderator
Username: unclemark

Post Number: 376
Registered: 08-2003
Posted on Monday, April 21, 2008 - 10:35 am:   Edit Post Print Post

I forsee a perfect application for computer gaming technology here. You are a boat in an anchorage with various depths, hazards, bottom conditions and other boats and have a given amount of rode on your bow and stern anchors. You deploy your anchors by means of mouse clicks with scope shown. The game applies the variability of wind direction and strength and you win or lose based on your destruction by the hazarding obstacles.
 

Anthony Clement
New member
Username: a_clement

Post Number: 1
Registered: 09-2007
Posted on Friday, April 18, 2008 - 03:25 pm:   Edit Post Print Post

After considering options with the "underfoot" anchoring Idea, if the short scope 'underfoot' anchor were to being to drag and not hold, an interesting option could be to simply start letting out scope (assuming you have room to swing without hitting anything dangerous) until you can let a little slack on your main anchor and then "set" the underfoot. The idea being if it got more windy, could you let out scope until you are effectively anchored in a "V" or Bohemian method. (??).
 

Ted Lavino
Moderator
Username: tlavino

Post Number: 60
Registered: 01-2006
Posted on Sunday, April 13, 2008 - 12:24 pm:   Edit Post Print Post

Seems to me that the "underfoot" technique is a way to get some of the benefits of the bahamian technique without requiring the amount of vessel maneuvering and requisite crew involvement of the bahamian. Since the scope is strictly limited, the holding power of the underfoot anchor would also limted, and will likely pop out of the sea floor and only able to resist dragging via friction along the bottom if enough pull is encountered (I'm thinking of the kiting scenario brought up by Marc, and also a reversing current or wind scenario). But seems to me that using the technique to limit, but not prevent wandering in light current and wind conditions where the pull is limited would prove useful in a crowded anchorage.

That being said, if high sideways loads are anticipated I would go to the trouble of setting a bow/stern.
 

Marc Hughston
Moderator
Username: hughston

Post Number: 635
Registered: 03-2003
Posted on Wednesday, April 02, 2008 - 10:02 pm:   Edit Post Print Post

Anchoring underfoot has limitations, but here is what I like about it in the two conditions I mentioned below where I think it has application:

1. Light wind. It's easy first of all, and that is probably the main issue as long as the expected wind and current don't drag you to where you don't want to be, or into rocks where you can't be. That's to say, the anchor underfoot simply dampens your movement - it does not prevent it.

In our case this last weekend at Emerald, we were in 45 feet with our bow pointing West and simply lowered the second anchor with 60 feet of rode. The action of the anchor underfoot kept us out of the kelp 50 feet away toward shore, and prevented the current from carrying us West toward the kelp that was choking Doctor's, all this while the wind was light and varable. Later after midnight the Westerly filled in to 13-15 knots, and the anchor underfoot kept us from yawing into the kelp.

2. Heavy Wind. I can't wait to use this technique next time at Cuyler Harbor when it's blowing 25-30 all night long, and the boat sails back and forth to her anchor just like a kite. Chafe on the anchor rode becomes a real problem in these conditions and I have made it a practice to take preventive measures, always involving getting up in the wee hours to adjust the chafing gear or change the way the rode leads, and that usually involves another person. If the boat wasn't sawing back and forth so much (as it would do without the anchor underfoot), we wouldn't have such an issue with chafe and might be able to leave it with just one trip on deck in the middle of the night instead of several.

So, what do you think? Let's talk Bahamian, bow and stern, etc.
 

Marc Hughston
Moderator
Username: hughston

Post Number: 634
Registered: 03-2003
Posted on Wednesday, April 02, 2008 - 09:23 pm:   Edit Post Print Post

Mark Howe read the message below and replied:

This sounds like a discussion that should be done in class.
We talked about reducing yaw by using two bow anchors like we practice; I have always called that Bahamian, except Mr. Hinz shows it deployed fore and aft. I believe Colgate calls that "two anchors on the bow" for use when current may reverse with a tide change. I would contend that in 25+ Bahamian is the way to go. This discussion would have gone well with our class last night on places to anchor in a storm.

Some serious faults I find with Hinz:
1. He doesn't address why his "underfoot" would be better than Bahamian. [It allows for a major swing with a wndshift.]
2. He says "underfoot" would prevent swinging into a hazard, which is precisely what it will not do.
3. His wording is poorly chosen when he says it "prevents yawing".
4. I would have to get used to his terminology; to me sheering is the sudden lurch a boat takes on a gust as opposed to normal yawing. Horsing? Ok, I can relate. Drudging? Nah, I think he just made that one up. It would definitely be good to get the terminology of all the different authors consolidated.

Great discussion. Would this work on the Electricmarine Board? (Here it is)
 

Marc Hughston
Moderator
Username: hughston

Post Number: 633
Registered: 03-2003
Posted on Wednesday, April 02, 2008 - 09:19 pm:   Edit Post Print Post

I hope we will have a lively discussion here with plenty of Q&A and comments. This thread grows out of a discussion in MST 215 on Monday the 31st, in which I related my results using a technique called Anchoring Underfoot out in front of the cliff and kelp bed between Doctor's Cove and the western entrance to Emerald Bay on Catalina.

To start things off, I sent this message to MST 215 students after class:

Hi All,

Here is the attachment covering what I call “Anchoring Underfoot” and what the author calls a “Hammerlock Moor.” This is the method we talked about tonight that I used to keep out of the kelp in front of Doctor’s – Emerald. This technique is ideal in two conditions: 1) light wind where the boat is susceptible to current and the general wandering about when on a single hook, and 2) heavy wind when the boat sails to her single anchor, back and forth like a kite. We did not talk about the second condition in class tonight, but it is very real in 25 knots + at anchor. We once collided with Mark Howe’s boat in the middle of the night at Santa Barbara Island due to this factor. We need to do this on the next trip if the conditions are right. I should add, I don’t think this is a good substitute for “bow and stern” at other anchorages like Willow, Goat Harbor, and Cabrillo Beach.

Click below to download the attachment
application/pdfAnchoring Underfoot
Anchoring Underfoot.pdf (332.8 k)

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