Fin aground on a sandbank.... actions?

Yes. sand is unforgiving stuff, however the OP has an encapsulated keel so the effects are mitigated somewhat.

It is just as well to be prepared but a couple of miles of shallow and a four, or more, hour window makes the chances of hitting Wales fairly small.
A trip to Scilly loosens you up a bit, it's possible to be quite laid back going over rocks with a couple of metres to spare.
 
langstonelayabout said:
In addition to the sage advice already given, this above is No.1.

Do your passage planning properly (have you done your Yachtmaster theory?) and you'll have a lovely day out sailing, knowing that you'll clear the bottom. Or you'll know that you have to go around, knowing that you will be safe. This is one of the real examples of planning two passages, each for different weather conditions.
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You hardly need yachtmaster theory to pick a route from A to B. The op obviously knows the risks of the chosen route, and the alternatives. They have opted to risk it and are looking for ideas to help if they get it wrong. Eminently sensible.
 
steve yates said:
You hardly need yachtmaster theory to pick a route from A to B. The op obviously knows the risks of the chosen route, and the alternatives. They have opted to risk it and are looking for ideas to help if they get it wrong. Eminently sensible.
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I was thinking more about the tidal heights at locations. I'd never used these before doing my YM.
 
If you're on mud, then reversing the way you came can work if you do it immediately - but get a crew member to peer into the strainer window and if is not clear stop.
I carry a lot of water (Half a ton) and managed to get off before by running all the taps and dumping water.
I have tow rope and bridle readily set up - its amazing how quickly fellow boaters in RIBs come by to help- but they often dont carry the equipment to take a yacht off. A good bridle is indispensable so they can motor your bow round.
Lastly - get a fortress as a kedge. I used to have a CQR and getting that and rowing it out in the dinghy was a nightmare.
If all else fails: Have a bit of plywood that hinges somewhere in your cockpit with one end hung from the boom. You can then get a level surface to eat and have a drink from. This is also the only time when scatter cushions are useful on a yacht. Use them to make a comfy snooozle snug whilst waiting for the tide.
 
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Yellow Ballad said:
I have about 2nm of sands to cross next week, they average +4m CD but some small areas of +7m which of course I want to avoid, HW is 10m so if I touch I should float off on the rising tide but...

If it all goes Pete Tong I would like to be forearmed with as much information to help get the boat down and back up with minimal "issues". We're talking Bristol Channel so I shouldn't be bouncing up and down for very long but it will be exposed (10kn forecast and neaps so notthing drastic). There's no real way round unless I want to extend the trip and it's a trip many from the club do and there's no real reason why it can't be done with enough tide and getting the timings right.

I'm thinking kedge to keep the bow in to the next flood tide, try and get het to lay so the cockpit is away from the incoming tide.
Bow anchor out short scope once we're down to keep us in place on the flood. (I'll have the benefit of seeing where the sands are when it's dry)
Close seacocks
Hatchboards in
Inflate dinghy
Notify coastguard

Any other thoughts, suggestions?
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You need to know what LW is, not HW.
 
Yellow Ballad,

for a start do you know how well your depthsounder works over deep soft mud ?

Obviously the moment you knew you'd touched the helm will be hard over and very likely engine on full, as hopefully you'll know the dodgiest part of your route.

As you may not have crew, I suppose if bothered you could have a heavy portable watercan already on the boom end and preventer lines rigged to heel her as suits while powering off, waggling the tiller to break suction of mud on keel.

Taking precautions like this may make one feel silly after it all goes perfectly, but I remember a phrase ' the gods like the flavour of sweat salt ' - and seamanship is all about preparation, you've already shown that by asking for tips here - have a safe and enjoyable trip.
 
Make sure the heads have been pumped clean & shut the seacocks to the heads..
Try not to reverse on sand if your rudder goes as deep as your keel. I did in the Murray Firth & caught a small boulder & it split the rudder & I ended up being towed into Inverness marina by the RNLI.

Otherwise, do not run aground in the first place . If not have the engine ready & lay the boat over hard & give it loads of welly. Being an east coast sailor I have run aground loads of times & never once used the anchor as it is just another faff to getting off. Just make sure that you do not get disorientated & know what way to go to get to deep water.

i ran aground in Bradwell creek last night at 00-30 hours & went base over apex over the mainsheet traveller & ended up ar.. over tit on the cockpit floor. So I suggest you remember to hold on if standing up. Fortunately my crew was holding on to the forstay otherwise he would have got a bit wet !!!!.
 
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I've a spreadsheet I produced where I can enter the tide details and get an hour by hour tidal height. When I expect to be pushing things a bit I colour it red, amber & green and print it out and laminate it so I have a handy ready reference.

You can also check www'pol.ac.uk to get a surge forecast which will give you a hint whether the tide will be above or below predictions.
 
Yellow Ballad said:
Well I need to know both but if I touch anywhere at the times I plan to be crossing I'll be high and dry by low water.

10.01m HW 3.86m LW
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Tom,

Are those 'heights of tide' relevant to Cardiff, to Newport, to Portishead, or to somewhere near The Bridges....? They suggest a Range for the Day of 6.15m which, without detailed study, suggests somewhere near Neaps.....?

You'll be aware that the times AND the predicted heights vary considerably around the inner Bristol Channel, - even over quite short distances - as do the charted sand/mud banks. Then there are effects caused by barometric pressure, and by recent rainfall up in the rivers' catchment areas.

All that makes the calcs and the decision-making rather more complex than the basic RYA course is geared to.
 
zoidberg said:
You'll be aware that the times AND the predicted heights vary considerably around the inner Bristol Channel, - even over quite short distances - as do the charted sand/mud banks. Then there are effects caused by barometric pressure, and by recent rainfall up in the rivers' catchment areas.

All that makes the calcs and the decision-making rather more complex than the basic RYA course is geared to.
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On the contrary, all of those issues were covered in my basic RYA course (though not with specific reference to Bristol Channel).
 
I've managed to read the thread but family day yesterday out so couldn't reply.

JBJag27, yes following tides are bigger. We're neaps going to springs I wouldn't risk getting stuck out there, I don't think I would fancy if if the tides were any smaller then what they will be.

Seajet, depth sounder works great on mud. The previous owner had kept the ageing Seafarer and when I bought the boat made it very clear that it was great for the channel as you can adjust the gain to work out if you're over mud, sand, rock etc. The boat lives on a drying soft deep mud mooring and I've tested it as I've lifted off with positive results. The repeater is a bit funny (for some reason it shows a 1 or 2 before the real depth), I have got a Nasa Duet I'm going to replace the repeater with but I plan on keeping the Seafarer as a backup for sticky situations. Thanks for the well wishes.

Daydream, all sea cocks are shut and only open when in use, I never leave them open (bar the engine inlet when sailing), but yes I wouldn't want to backflow the toilet for sure!

Wil/Zoidberg, I've taken those heights from Avonmouth but I've checked Newport as well and although slightly lower I'll I'll be closer to Avonmouth near their HW where the larger part of the banks are. As I mention below, I'll be keeping my eye close to the sounder, curve and charts and if anything doesn't seem right I'll be looking for an escape route.

As I said before it's a "usual" route for other club members so I'm not expecting it to be troublesome but it's the first time I'll have done it. I don't plan on running aground in the first place, I would be checking depths before and on the bank against the chart, tidal curve and sounder. If I'm in any doubt I'll sail to deeper water/on the spot till the tide turns and run down to Cardiff.... But the forecast has changed a bit and it's gone lighter so I'm not sure I can make my speed over the grounds without using the engine which I don't like doing. The morning wind seems better so it looks like I can make a nice broad reach down to Cardiff get some breakfast and head up on the next tide Portishead on the lighter wind with the tide doing the hard work and this week sailing is to get as much sailing done as possible so sounds like a new plan.

It's still a useful thread, I'm sure at some point I'll get caught out so worth while knowing this stuff.

Cheers all.
 
It's not at all clear where Tom in 'Sundance' is looking to do a Dulcibella. Over the Welsh Grounds, perhaps......?

42634023510_63b92ee214_b.jpg



.......or further up beyond The Bridges......

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The warning of 'Changing Depths' in several places on the charts warrants a moment's pause. I can't think of an area around the UK where the tidal height calcs would get less 'predictable'.


It'll be a challenging exercise in pilotage, and no mistake. Do I sense a Mike Peyton-style cartoon coming up?
 
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Zoidberg and Antarctic Pilot I agree, that sort of complex situation was not covered in my YM Offshore; maybe the nous to realise the problem, but no easy quick calculation around it !

Yellow Ballad,

I so agree with keeping the Seafarer depthsounder, as you say tweaking the gain showed the seabed consistency - modern depthsounders just don't do that no matter how one fiddles with gain and sampling rate.

For this reason I have a standard digital depth display in the cockpit, and a fishfinder ( along with other instruments ) on a swing-out panel; I ran short of time this year but over winter the fishfinder - a Garmin £130 job with colour display and built in GPS which makes for a handy backup to the plotter - will become primary in the cockpit and simple depthsounder below so I can see it from my bunk, or if shut down below cowering from the conditions...

Must say though Bristol is the only city I like I've never found the whole Bristol Channel attractive, like sailing through Oxtail soup with lots of firmer mud and not much in the way of decent harbours; if only De Savory had built a handy harbour just to the west of there, instead of tarting up Lands End...
 
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