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Draining after capsize

Started by Overomtimistix, 14 May 2013, 01:09

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Overomtimistix

In my Baggy Trousers, there is a low stern tank which extends a little under the floor. The centreboard case is pretty low and extends only about 8 - 10" above the floor.

After a capsize, on the river at Desborough, the natural water line is about level with the top of the centreboard case or just above depending on the weight of the crew. I have managed to sail out singlehanded, but never with even the lightest of crews.

The forward and aft tanks are both empty.

Is there some underlying problem with my boat? Are there any simple steps I can take to improve things?

I am considering whether adding some thin tubular bags either side of the centreboard would add enough floatation to make a difference, or whether they would be too much in the way; obstructing access to the bailers and operation of the tackle for the jib tension and lowers that run along the floor there.

One sugestion is that the boat was put together with sailing on the sea in mind,which would provide more bouancy.
Dan
N3342

tom lee

draining an AC after a capsize requires a bit of skill and practice  as you say, the water level is usualy above thecenterboard case. basically you need to get some speed and sit back  to empty the water.

here are the steps we  follow:
- right the boat
- balance the boat and untangle everything
- open self bailers and release transom flap elastic
- centerbboard half up
- pull jib sheet tight and ease the main to allow the boat to bear away (the water is causing lots of weather helm and the rudder doesn't work as the boat is not moving)
- keep balancing the boat!!
- once on a beam reach, start pulling the mainsheet in gently (keep the jib tight until a lot of water has come out) and both helm and crew need to sit as far back as possible while still balancing the boat. You might be sitting under water at this point.
- as speed builts keep pulling the main in until it is trimmer properly and go for speed the jib can also be eased a bit at this point.
- assuming there is enough wind,the water will empty quickly down to the level of the top of the aft tank then move forward a bit to help the selfbailers drain the rest of the water.

Hope this helps
Tom
N3268
Tom<br />N3545

Biniou

The best way is not to capsize!;)

jonathan_twite

I have plenty of experience in filling up my Paper Dart, but as we sail on a river, we struggle to get the water to go out of the back.  A beam reach is usually straight at the shore... This is the method we have come up with.
A Paper Dart has quite a deep cockpit and so we can easily have a bucket perminantly stowed up the front, but still out of the way.
- The Helm rights the boat "scooping" up the crew.  The Helm does NOT get in but stays floating next to the shroud.  In doing this, they can control the rate that the boat comes up so limiting the chance that the boat will keep comming over and capsize the other way. They can then help balance the boat by holding the shroud.
- The crew then unattaches the bucket and bails like mad.  It only takes a couple of minutes to get the water level below the centreboard case.  We have a small hand bailer that the Helm helps with, bailing from outside.
- Once the water is below the centreboard case, the Helm can get back into the boat.
What happens next depends on the conditions.  If it is blowing a gale, we concentrate on getting a large amount of the water out so we can then concentrate on sailing.  If the wind is less, the helm concentrates on sailing, while the crew keeps bailing.
 
An old Enterprise trick is to stuff something (Shirt, Towel etc.) in the top of the centreboard case after capsize so water doesn't come back up it as you are bailing out.
 
Happy Swimming!
Jon
2709
N3162 (Baggy Trousers) "Bicycle Clips"
N2709 (Paper Dart) "Goose Hunter"

Overomtimistix

More practice bailing for the crew - and possibly something to block up the centreboard case.
I didn't mention that there are no transom flaps but the water drains fairly effectively over the stern tank with a little bit of motion.
Thanks for the suggestions.

Ed storey

I bought a double bottomed boat!
 
Ed

Alex D

Alex <br />(ex N3455, N3246)

icecreamman

The joys of sailing on a river tend to be that in one direction it is a beat and going the other way will make it a run or a very broad reach. As everyone has mentioned, the most important thing to do is to get the water out of the boat as fast as possible. Depending on how things are going for you, one last option to look at might be sailing for the windward bank, beaching temporarily and tipping the water out of the back of the boat. Once you have got rid of the majority, push the boat back into the water and get rid of the rest using the self bailers. You will have to weigh up the time taken to park up and empty against your time slowly moving round the course getting the water out. 
The best way to solve this problem is as everyone will tell you after the event is not to plop the boat in the drink. Good luck with however you do it!!

angus

Transum flaps are important for draining a single bottom boat, they serve two functions 1 they stop the water rushing back in when you slow down and 2 they let you see when you have got it right as they open.
It is possible to drain the boat with out flaps but a soon as the wind dies or you heel too much or slow down for som other reason you have to scuttle forward to try and stop the water rushing in. Then when the wind gets back up if you don't get back quick enought it is dive dive dive and up periscope.
All smoke and Mirrors. N2153, 2969, 3411

Overomtimistix

I have taken some measurements and will try to construct some flaps they will need to be about 18" wide and 4" high to fill the (designed) hole in the transom either side of the tiller.
Would a T-foil rudder help in this situation? or would that be just throwing money at the problem with little gain?

angus

2mm Acrylic is I think the stuff you want, you can try this place they appear to cut it to size. use one piece held in place with the rudder pintles. Problem is postage will probably cost more than the acrylic.
http://www.cutplasticsheeting.co.uk/clear-acrylic-sheeting/clear-perspex-acrylic.html 
 
 
All smoke and Mirrors. N2153, 2969, 3411

John Nixon (Guest)

http://www.sailboats.co.uk/Catalogue~Mylar_Transom_Flap_W50cm_L30cm~p_K903~c4657.html
Cut them out with sissors and stick on with the tape supplied. Always worked for me.

Overomtimistix

Thanks Angus, I have a roll of acrylic about 2mm left over from putting new windows in the kids' bike shed.
I had been thinking of taping it on along the top but your suggestion of putting it behind the rudder pintles sounds good. The flap will be flexible enough not to need a hinge initially.

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