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Old 12-02-2009, 16:02   #1
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Someone please explain this to me.

I'm anchored now and the tide is coming in fast. The dinghy is surfing around far behind the boat. My wind meter is reading 1.3 at the moment. My wheel is locked at centerline. My common sense tells me that my anchor line should be going forward off the boat but it's going back under the boat and its tight. I have experienced this a bunch of times in varying wind conditions.

So what gives? I don't get it.
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Old 12-02-2009, 16:10   #2
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AO'

Lock the wheel over at about 15 degees and see if the boat settles down differently. My long keel Rhodes Reliant is a different animal altogether in conflicting conditions when I do this.
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Old 12-02-2009, 16:25   #3
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Where are the wind and current relative to your boat?
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Old 12-02-2009, 16:25   #4
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Originally Posted by Aquah0lic View Post
I'm anchored now and the tide is coming in fast. The dinghy is surfing around far behind the boat. My wind meter is reading 1.3 at the moment. My wheel is locked at centerline. My common sense tells me that my anchor line should be going forward off the boat but it's going back under the boat and its tight. I have experienced this a bunch of times in varying wind conditions.

So what gives? I don't get it.
Are you saying wind is opposing the tide? In this case the dinghy is mostly wind drag and goes downwind, your KB is much more subject to current and moves where the current pushes it. This is why they caution about anchoring near powerboats, as they might be lieing to the wind, and you could be lieing to the current.

If that wasn't what you were describing, then Never Mind.

John
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Old 12-02-2009, 16:58   #5
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OK, the wind is 0 mph. I just tried locking the wheel in various positions and I finally got the rode to go out forward then locked it back to center. The boat drove past the anchor, against the current with no wind. I was standing on the bow looking at the current rip past the rode as I passed it. The current is directly on the bow. I'm at a loss.
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Old 12-02-2009, 17:12   #6
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How deep is the water?? Where are you anchored? Give me your exact position on your GPS.
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Old 12-02-2009, 17:16   #7
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Here's a guess: The rode pulls slightly to one side or another, even with the wheel centered, and once the rode is pulling off center, the current going past the keel produces lift, and the boat "sails" forward as if there were sails up but instead the side force comes from the anchor rode instead of the sails. Equilibrium is reached when the rode & anchor are behind the boat and further forward travel is impossible.
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Old 12-02-2009, 17:25   #8
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Here's a guess: The rode pulls slightly to one side or another, even with the wheel centered, and once the rode is pulling off center, the current going past the keel produces lift, and the boat "sails" forward as if there were sails up but instead the side force comes from the anchor rode instead of the sails. Equilibrium is reached when the rode & anchor are behind the boat and further forward travel is impossible.
WHATTTTTTTTTT????????

If the boat were "Current Sailing" up on the anchor, the rode would go off to one side, then the other when it tacks. That only happens when you have a breeze astern.....

When anchoring in a tidal flow, it is best to put one anchor up stream and one down stream. Both anchors coming from the bow so when the tide changes, you have a new anchor to fall back on. If you end up with a beam wind, you have 2 anchors keeping you off shore.

Cairns Aust is famous for weird stuff happening at anchor. I think I snagged about one boat every other day that dragged down that river after a tide shift.

The other thing is, the surface water can be going one direction and deeper water going the other, just before slck tide.

If it is a crowded anchorage, be sure to tell you neighbors how you are anchored.
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Old 12-02-2009, 17:32   #9
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AO,

I'm not a hydro-dynamicist-- and I don't play one on TV, but I have experienced the same thing. Your comments indicate that my suggestion made a difference. I put it down to something like heaving-to under sail, but maybe with flow across the keel generating some sort of "lift". Hey Guys!! tell me ain,t so, I would love to hear an explanation.
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Old 12-02-2009, 17:37   #10
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How deep is the water?? Where are you anchored? Give me your exact position on your GPS.
30 41 061 N
81 28 299 W
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Old 12-02-2009, 17:38   #11
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Hey, I said it was a guess. My boat does the same thing. The boat will swing or tack from side to side while anchored with a headwind but in dead calm with current from ahead, the boat will "sail" forward until equilibrium is reached. Think of what a simple kite does when flying and lay the whole thing horizontally. The kite string is the rode, the wind is the current, and the kite is the keel/rudder combo. If that ain't whats happening then I can't explain it. Interesting thing is my boat only does this with the wheel brake on. If I take the brake off the wheel, and the rudder is free to move, then the boat does tack as you describe.
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Old 12-02-2009, 17:40   #12
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Here's a guess: The rode pulls slightly to one side or another, even with the wheel centered, and once the rode is pulling off center, the current going past the keel produces lift, and the boat "sails" forward as if there were sails up but instead the side force comes from the anchor rode instead of the sails. Equilibrium is reached when the rode & anchor are behind the boat and further forward travel is impossible.

As crazy as this sounds, I'd have to say plausable and the best reason so far.
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Old 12-02-2009, 17:46   #13
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When anchoring in a tidal flow, it is best to put one anchor up stream and one down stream. Both anchors coming from the bow so when the tide changes, you have a new anchor to fall back on. If you end up with a beam wind, you have 2 anchors keeping you off shore.


The other thing is, the surface water can be going one direction and deeper water going the other, just before slck tide.

The water direction thing is news to me, I thought it moved at different speeds but the same direction.

The 2 anchors idea sounds like a good idea, but my wing keel sometimes snags the rode and holds it when it goes under the boat. It causes me worry occasionally.
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Old 12-02-2009, 17:55   #14
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30 41 061 N
81 28 299 W
OK....you are sitting right on the bend of a river. You are in an area of extreme tidal flow on the surface but the current below could actually be going the opposite direction. This is common in the bend of a river. The other possibility is that your keel is in the mud .

If you look straight across the river, you will see a sand bank. That is caused by the water turbulence picking up sand from the side you are on and placing it over there.

Google earth actually shows you on land. Maybe an aligator has your keel....

Creative spot to anchor. I've never anchored up there, all the times I've done the ditch.

Is this your position:
30 41 06.1n 81 28 02.99 W

If you're at 30 41 06.1n 81 28 29.9 W......you're in real trouble.....
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Old 12-02-2009, 18:00   #15
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What position was the wheel when you got her to sit down current??

Try getting down current again, and instead of locking the wheel...put a bungy cord on it...let the rudder have some give. Beyond that you could have cross currents as Kanani indicates?

How much scope do you have out?
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