Wind Against Tide

[MicHughV]

wind against tide moments are one of the few times why I question my penchant for cruising on a sailboat

[Iron E]

Originally Posted by mikereed100

That is a fairly common situation. I have been using Gord's solution for decades now, the last time being the night before last. It works well, but the fly in the ointment is that at some point the wind or the current will die or switch, rendering the spring line ineffective or, worse, under the boat wrapped around the keel or rudder. A stern anchor is the surest solution but can be an annoyance. Also, if the other boats in the anchorage are not using stern anchors as well, this is not an option. Even without a stern anchor each boat will behave differently depending on windage and bottom configuration, creating what they refer to in Mexico as the "La Paz Walze", in which every boat in the anchorage is marching to the beat of a different drummer.

So what do you do? If I can get away with it I will set a stern anchor. It helps if you have set your boat up so that you can do this without deploying the dinghy. If there are other boats around swinging on one hook so that a stern anchor is not an option I will often use a springline as described, expecting that at some point I will have to remove it. The other, and sometimes best, option is to simply leave a lot of room between yourself and the other boats and put up with it.

Ah... The La Paz Waltz This guy knows^^^

[LAGO]

I've been caught by the tide like this (wind Vs tide) behind Fraser Island Oz in a 38' cat. The anchor ended up behind us with wind from astern pinning us over the chain. In the bigger gusts the chain would slap the tunnel! Not a pleasant few hours. I couldn't manoeuvre the boat around because the chain was catching on the mini-keels and maybe rudders and props.

What I learnt from this was: avoid areas like the shallow anchorages like Fraser Island in spring tides. Deep water = slower water. And don't put too much chain out in shallow water. But is was pretty windy.
We have also tried a drogue off the stern which helped a bit but when the tide slows down the drogue can get caught on your rudders.

[GordMay]

Originally Posted by Cheechako

.... How do you pull an anchor when the rodes have become one big rode and the anchors are widely spread apart?
You dingy out and find a way to remove one anchor from the bottom, carry it to the bow in the dingy and manhandle it around the rode many times or remove the shackle and do so!

Or, disconnect one rode, from the boat, and unwind it, from the other, from the deck, on board. Sometimes, I collected the first rode, in a bucket, whilst unwinding.

[Johan Leopard51]

We’re a shallow draft 51 foot motor cat and a bridle and last trip in about 10m water with 30m-35m chain out, had hassles : dragged anchor.

Strong current had vessel 90 degrees to wind, so I figure that is why in modest wind about 12 knots we dragged anchor that was set in sand under motor astern. My cat was now presenting a big wind profile compared to the force that 12knot would have with her sitting like she should without current. The drag thing only happens with strong current across wind. Swell is not an issue as we tend to anchor in lee of islands/atoll/reef, so almost never have swell onto bow.

It was night and basically uncharted map, so I chose to lift anchor, follow bread crumb out to deeper water and look for a new spot that turned out to be next island 18nm away. Easy in a power cat but might have been tougher in a sail cat.

Q : my anchor is not the OEM anchor (have a management company to thank for that). How do I pick the “best” anchor for my yacht that anchors (1) basically never in mud and for sake of coral we pick (2) a sandy patch about three tennis court in size.

[RaymondR]

Originally Posted by GordMay

Or, disconnect one rode, from the boat, and unwind it, from the other, from the deck, on board. Sometimes, I collected the first rode, in a bucket, whilst unwinding.

My second anchor is on a fairly long length of 3/4" nylon and won't fit in a bucket so I tie the coil with a piece of rope so I can lower it below the level of the bowsprit and hook the coil with the boat hook.

To stop the second anchored rode rubbing against the hull I shackle the nylon rode to the anchor chain and lower the shackle down to about 10' below the surface.

It's all a nuisance but I have found the second anchor to be the only effective solution to a serious wind against tide situation.

[noelex 77]

Originally Posted by Johan Leopard51

We’re a shallow draft 51 foot motor cat and a bridle and last trip in about 10m water with 30m-35m chain out, had hassles : dragged anchor.

Strong current had vessel 90 degrees to wind, so I figure that is why in modest wind about 12 knots we dragged anchor that was set in sand under motor astern.

My sympathy, dragging is never pleasant even in light wind.

You will find lots of discussion on anchor design in various threads on this forum:

You can look at Panope excellent tests (or find a more extensive number on YouTube).
https://www.cruisersforum.com/forums...-155412-7.html

Or this thread with photos of anchors in the real world:
https://www.cruisersforum.com/forums...26073-129.html

Sand is one of the common substrates and any of the excelent general purpose anchors will work well. My personal favourite is the Mantus M1, but I doubt a rollbar anchor will fit your cat so the steel Spade is more appropriate. Both of these models can penetrate even hard sand, something lesser models struggle to achieve.

Fit the largest size you can comfortably manage.

[dannc]

Originally Posted by Johan Leopard51

We’re a shallow draft 51 foot motor cat and a bridle and last trip in about 10m water with 30m-35m chain out, had hassles : dragged anchor...

Maybe use more scope? 10 meter water with 30-35 meter of chain is only 3.5:1 scope at best. If the chain is secured at deck level, the height of the deck from the water should also be included in the amount of scope that is needed.

[Johan Leopard51]

Originally Posted by noelex 77

My sympathy, dragging is never pleasant even in light wind.


Fit the largest size you can comfortably manage.

Thanks, I’m new here so will dig some more.

I figure our chain out weighs more than the anchor mostly so want to focus on anchor design.

Our problem is only when that 90 degree current. I like dropping, letting out almost intended chain, secure chain at windlass, go astern downwind on motors till quite certain anchor is ploughed in, then let out last 5m chain, attach bridle, and we for some habitual reason drop about 8m chain behind the bridle.

I have a few spare anchors people lost that we’ve dived out. (We dive/snorkel half the day) One was interesting : not sure the terms but basically it has the double plough that one’d settle and then the anchor arm can swivel not far off 180 degree my side of the double plough. Think it is only around 27kg or so but i like the design vs the normal fixed arm.

[Johan Leopard51]

Originally Posted by dannc

Maybe use more scope? 10 meter water with 30-35 meter of chain is only 3.5:1 scope at best. If the chain is secured at deck level, the height of the deck from the water should also be included in the amount of scope that is needed.

We tend to (1) spend 2 nights per island/reef (2) not boat in Indian Ocean in high wind (3) pick an anchor if there is no fixed mooring that is in wind shadow of the little island / reef / atoll. So 9/10 all fine, but with atolls the drop-off can be huge (50m behind your 10m anchor it is deep deep) and atolls especially the current effect can be huge.

Part of 3.5 scope is to not damage reefs if yacht does circles in low wind high current. I try pick a large sandy bottom which is why we arrive 2hrs before sunset. 8-12 knot wind is not much imho - often we have calm wind and drop 2.5 scope? MOST (not all) People have no idea of the devastation that lots of chain causes in reefs until they snorkel / scuba below their own vessel. Imagine a 30m circle of destruction… We’ve also salvaged plenty of anchors still attached to chain that some visitor unable to snorkel 10m could not free with air ballast, so left it all down there because they dropped anchor in reef area instead of sand area. We normally leave the chain and salvage the anchor which is appreciated back in marina where anchors are scarce inventory - probably because charter yachts keep leaving theirs in the reef!

[noelex 77]

Originally Posted by Johan Leopard51

Thanks, I’m new here so will dig some more.
I figure our chain out weighs more than the anchor mostly so want to focus on anchor design.

Originally Posted by Johan Leopard51

Our problem is only when that 90 degree current.

With decent anchoring equipment you should not be dragging in anything like 12 knots of wind, irrespective of whether or not current is orientating the vessel at right angles to the wind.

Originally Posted by Johan Leopard51

(We dive/snorkel half the day)

Take a note of the anchor designs that are performing well. There is a huge difference between anchors that are burying well and those that can only heap up sand in front of the fluke.

Originally Posted by Johan Leopard51

One was interesting : not sure the terms but basically it has the double plough that one’d settle and then the anchor arm can swivel not far off 180 degree my side of the double plough. Think it is only around 27kg or so but i like the design vs the normal fixed arm.

There are all sorts of weird anchor designs. Concentrate on the well regarded and proven designs if you want to achieve anchoring success.

[wholybee]

Originally Posted by Johan Leopard51

We’re a shallow draft 51 foot motor cat and a bridle and last trip in about 10m water with 30m-35m chain out, had hassles : dragged anchor.

Strong current had vessel 90 degrees to wind, so I figure that is why in modest wind about 12 knots we dragged anchor that was set in sand under motor astern. My cat was now presenting a big wind profile compared to the force that 12knot would have with her sitting like she should without current. The drag thing only happens with strong current across wind. Swell is not an issue as we tend to anchor in lee of islands/atoll/reef, so almost never have swell onto bow.

It was night and basically uncharted map, so I chose to lift anchor, follow bread crumb out to deeper water and look for a new spot that turned out to be next island 18nm away. Easy in a power cat but might have been tougher in a sail cat.

Q : my anchor is not the OEM anchor (have a management company to thank for that). How do I pick the “best” anchor for my yacht that anchors (1) basically never in mud and for sake of coral we pick (2) a sandy patch about three tennis court in size.

With a scope of 3.5:1, that works with some boats with modern anchors or the right size, in anchorages with good holding. But best practice and what any sailing school will tell you, 5:1 for normal conditions, and 7:1 for poor conditions. So based on that, you didn't have enough scope.

Any modern anchor sized per the recommendations from the manufacturer should be fine. It wouldn't surprise me if a management company sized the anchors one size small to save money and make handling easier. Panope's tests and videos that were linked in another post are great to watch.

A properly sized anchor with enough scope should easily hold when the boat turns beam to the current, as that is a very common and normal situation.

[Johan Leopard51]

I’ll focus on getting the right anchor design

[Tupaia]

Originally Posted by noelex 77

Sand is one of the common substrates and any of the excelent general purpose anchors will work well. My personal favourite is the Mantus M1, but I doubt a rollbar anchor will fit your cat so the steel Spade is more appropriate. Both of these models can penetrate even hard sand, something lesser models struggle to achieve.

Fit the largest size you can comfortably manage.

I second the first statement, coral sand often has a hard crust that many anchor designs cannot penetrate and will therefore not bury properly. A Spade anchor has a very sharp point and is very effective at penetrating the crust.


I disagree with the second statement. Fit an anchor that is sized for the boat. Oversized anchors may seem like a good idea. The heavier the better!! But, it can actually diminish the holding power, that is achieved by the bury not by the weight. A big oversized anchor that cannot be buried sufficiently because the vessel cannot set it will result in less holding than a smaller correctly sized anchor that can be set to a proper depth.

[Leadfree]

The earlier suggestion of a swell bridle is not relevant to the situation.

You will have to retract the sprit. You will also have to rig two anchors, the setup is frequently called ‘Bahamian Moor’ and if you Google that term you’ll find lots of directions for same. The rodes do twist and it is something I deal with. My experience (and I literally spend months in a tidal sound in the Bahamas) is that given ambient wind, twist doesn’t happen that quickly and when it does I just take the dinghy and unwind the rodes by pushing the boat in circles in light wind and between currents (usually about :30 between current). Alternatively I could untwist from the deck as I keep my secondary rode in a crate (8-brait). My advice is to not let twist get out of hand, and maintenance is just part of good seamanship