Or trying to justify how I cocked up at Percy Island and ended up with the boat sitting on the Sand for an hour at low tide.

The art of Anchoring, or as some of us more seasoned old salts like to call it, "Parking", has a number of elements to consider to successfully "Park" the boat for a stop along your journey.

1: The parking spot should provide a comfortable place to stop.

2: Once stopped, the boat should not decide to continue the journey on its own, while you sleep.

(The bold Italics in the above sentence according to MS Word, apparently are Reflexive Pronoun use and I should consider revising it. If I had the foggiest clue what a Reflexive Pronoun was I might, but I don't, so I won't.)

3: If the boat moves around on its parking chain (which they do quiet often), it is a lot more comfortable if it cannot hit something else like the sea bottom, the shore line or any boat parking in the vicinity as well.

To achieve the above involves some science and some art. This may get a bit technical, so if it does, go make a coffee, grab a biscuit and skip to the pretty pictures down below or else try to stick with me on this and in the end you will, like myself, realise that the fact the boat ended up aground on the sand had little to do with me. It is never my fault.

The Parking Spot: You are trying to stop in place out of the wind and away from the influence of swell and waves. A cruising guide may give you some good suggestions for that elusive parking position, indicated on a crudely drawn map an appropriate place to stop by a friendly little anchor symbol. The problem with this is that it is merely a suggestion, but 9 out of 10 boats all have the same cruising guide and attempt to place their anchor exactly where above mentioned crudely drawn map indicates. Result - crowded parking spots.

So the trick is to cruise around the parking area noting the effect of wind and swell while all the time watching the depth. There I said it Depth this is where we get technical. The depth you stop in dictates the amount of chain you put out with the anchor and this is the device with which you are trying to stop the boat deciding to continue the journey on its own (there is that Reflexive thing again) with out you in control.

The amount of chain is referred to as Scope and for most situations I use a 5:1 ratio IE: The chain used is 5 times the water depth. Water depth - there is another variable, unlike a lake or places like The Mediterranean Sea with no tide, the area we try to park in is affected by tides. The water keeps getting deeper until it stops then it gets shallower again then repeats every six hours or so. So while I am tootling around the parking lot keeping note of wind and swell effects, I am watching the depth in the knowledge that it will get shallower at low tide and deeper at high tide in any given spot. This may seem bleedingly obvious to some, but obviously not to all as witnessed by the number of boats seen trying to depart the parking lot on their own at high tide. (The owner parked at low tide and because the scope was insufficient at high tide the anchor has lifted off the bottom and boat is on the move.)

So, for argument sake, I will look at the Percy Island numbers by way of an example. On approach I have looked up what the current state of tide is 3.7 m and dropping. Next low tide is .7 m in a few hours. The next high tide Later in the night will be a high off 6.7 metres. So with these figures in my mind I look at the depths of water available in a suitable places to park and make my decision.

I like to anchor as shallow as possible because this reduces the scope mentioned above and with a shorter parking chain the boat swings in a smaller circle, it should be obvious from the 5:1 ratio that the deeper the water you stop in the larger the circle the boat swigs around in with more potential to hit the shore line or any boat parking in the vicinity.

So I normally look for 1-metre below my keel at the lowest tide we will encounter in the area at anchor. Back to the example and the science. Low is .7m so the depth will drop by 3 metres I want 1m at low tide so I need to stop in a minimum of 4m of water below my keel so after hitting low tide I will not hit the bottom, in fact I will miss the bottom by my 1 metre. So my ideal depth to look for is 4 metres in which to drop the anchor in. The amount of anchor chain I drop (scope) will be 5 times the maximum depth of water measured from the sea floor to the attachment point on my boat of the anchor (in my case 1 metre above the surface of the water).

Here comes the science, well maths anyway. I am reading 4 metres (my ideal depth to drop the anchor in) this measurement on my depth meter is reading at my keel 1.4 metres below the water surface so that needs to be added to the depth. The rise in tide from now till high tide is 3 metres so we add that. The attachment point is 1 metre above the water surface so that needs to be added to the depth as well then the whole thing multiplied by five to give me my anchor. (4mt + 1.4mt + 3mt + 1 mt) x 5 = 47 meters of chain required.

So we will be perfectly anchored in 1 meter of water below our keel at low water and be swinging around on 50 meters of chain at high water that will keep us perfectly safe and away from the shore and the inevitable other parked boats.

Easy peasey not so squeezzy,

SO WHAT WENT WRONG!!!! I missed by 1000mm

Going in, I did not add the 1 metre safety to the drop of 3m and anchored in 3m of water that ended up at low tide being Zero metres (just as I had worked out) below our keel and we were aground on the sand for an hour.

Being aground on sand is not a big problem, but the swell had the 21 ton moveable object namely More R&R bouncing up and down on the not so movable object - the sea bottom, with a jarring shudder through the boat each time. Once enough water had departed from beneath the boat it was very peaceful for an hour while we also became part of the sea bottom for a while then the bouncing returned as the tide came back in until we floated again.

So there you have it, I forgot 1 metre and that resulted in the fore mentioned grounding.

Here we are aground at Low tide 0635 five minutes after we were due to leave.



We managed to extract ourselves just after 7 am and departed through the anchored (Parked) vessels.



Had a 65 mile motor sail through to Scawfell Island.



I slept like a baby after the previous night spent worrying about why we had gone aground and what we would do in the am to get off again.



Today was a a short hop across to Brampton Island under sail all the way, 22 miles. Anchored off the old resort, Roast Pork and all the trimmings tonight as Clear Horizons makes a dash to Abell Point to have his stitches out tomorrow, while we may head across to the Newrey Islands for a Day.