Tidal heights - it's easy to get them wrong

Koeketiene

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Strong cleats though

11896145_723098074501218_7021731665547263530_n.jpg
 

VicS

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Is that the feed back from this recent question

Where to Dry Out in Guernsey - need to inspect rock damage

Yes I hit some French granite! Was in an anchorage between Ile Grande and Ile Morvil (north of Trebeurden.) Unmarked ( no buoy or post) and not on my Navionics chart. No water in the bilge - I've got an encapsulated keel. But there is bound to be some damage to the GRP. I told my insurers and headed for Guernsey.

Next I think I need to dry out and inspect the damage. Of course I can use a travel-lift (Boatworks or at St Samson) but I was hoping to avoid the expense. I'm thinking a nice sheltered wall to lean on, or posts like at Warsash. Have you done that in Guernsey? Or have any advice on where's a good place?
 

BobnLesley

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We all get it wrong occasionally, after all the published tidal heights are only 'predictions' anyway, aside from cock-ups, if you throw in some particularly high/low air pressure or a strong wind from a constant direction for several days it can easily throw your calculations; that said, to get it as wrong as that photo shows has taken some real effort and commitment. All said smugly from the St John's River Florida, with it's spring tide range of 8".
 
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johnalison

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That doesn't look so much like a tidal miscalculation so much as a boat that has fallen away from the wall while drying. Bad mistake. Worse than failing to attend your lines in a lock going down and having to use a knife to free yourself, which I have seen.
 

trapezeartist

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We all get it wrong occasionally, after all the published tidal heights are only 'predictions' anyway, aside from cock-ups, if you throw in some particularly high/low air pressure or a strong wind from a constant direction for several days it can easily throw your calculations; that said, to get it as wrong as that photo shows has taken some real effort and commitment. All said smugly from the St John's River Florida, with it's spring tide range of 8".

I don't think the skipper can blame that one on atmospheric pressure! All said smugly from a place where the spring tide range is 45 feet.
 

RichardS

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That doesn't look so much like a tidal miscalculation so much as a boat that has fallen away from the wall while drying. Bad mistake. Worse than failing to attend your lines in a lock going down and having to use a knife to free yourself, which I have seen.

I don't sail in a tidal area so I'm not really qualified to comment but ....... if you fall away from the wall whilst drying out wouldn't the bottom of the keel still be planted where it first touched the bottom rather than against the wall?

Richard
 

johnalison

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It looks as if the lines tightened as the boat descended but I can't believe that the skipper made a calculation of the tidal height and set his lines to that length. I suspect that he took his eye off the ball at the wrong moment. When I dry out I use the sounder to give me a rough guide of how much water I have.
 

Robin

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That doesn't look so much like a tidal miscalculation so much as a boat that has fallen away from the wall while drying. Bad mistake. Worse than failing to attend your lines in a lock going down and having to use a knife to free yourself, which I have seen.

That is very recognizably the drying ramp inside Victoria marina in at Peter Port Guernsey so yes you are 100% correct A halyard taken to a point on the quay wall may have helped lean it the right way on taking the ground.


I once saw a brand new Westerly ketch ( Renown or similar) hanging on it's bar taut warps from the quayside in Fowey. Whilst I was watching, the owners returned in full best duds, he in dinner suit and she in super smart gown they had to cut the lines but fortunately the boat drop back in the water with no damage. I remember thinking they did not deserve such a nice boat when there was me with only an old plywood 21 footer, but matbe it was chartered. AS far as I remember it did not have a blue ensign......... .
 

DannyB

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Reminds me of an incident many years ago when I was a rookie copper. In the district car with the sergeant when we got a call to go to the harbour and meet the night watchman from a trawler. When we got there the night watchman was hysterical, jumping from foot to foot and stinking of booze, when we calmed him down enough to get a coherent story from him, it turned out the skipper had left him on board, his sole duty was to attend to the mooring warps, so he thought he'd go and have a swift pint in the local boozer. He'd obviously had more than one because he pointed us to a fairly large steel trawler hanging suspended from her warps. The warps were under so much strain you could hear them humming. We advised him it wasn't a police matter and recommended he phone the skipper. You would have had to put an axe through the warps but I wouldn't like to get that close. Not sure what happened in the end, we had to go and attend somewhere else.
 

KAL

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That is very recognizably the drying ramp inside Victoria marina in at Peter Port Guernsey so yes you are 100% correct A halyard taken to a point on the quay wall may have helped lean it the right way on taking the ground.[\QUOTE]

It's also a very long time ago!
 

Robin

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When was that picture taken? Not seen a Woolworths for decades!

Ages Me, because we used to have a last minute shop there for 'PIck'n Mix' sweeties to suck going home along with a bag of M&S extra large peanuts from the M&S (Aka 'Creasy's) next door. I also remember being there on a very big spring tide when the road in front of those stores was flooded and the ramp from the pontoons to the dock went downwards to the quay not up. We left shortly after that and had >18kts SOG under sail through Alderney Race in our then W33 ketch.


There is a local postcard and sets of pictorial table pace mats sold in the shops along the quay picturing the marina with SWMBO in the foreground Looking very tasty in her bikini whilst cleaning the decks of the then W33. I must try and find a copy to scan...;)
 
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