Sinking again!

pmagowan

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Sticking to the subject of sinking I was thinking that most people, while underway, are completely unaware that they have a breach in their hull until such time that the cabin sole is awash. At this point valuable time has been wasted and also it is much more difficult to identify the source of the leak or even if it comes from forward or aft. I was thinking that there must be or should be a device that can monitor the bilges and immediately warn of water but also to remember the order in which the bilge filled. So, for instance, the bilge divided into 3 sections with 3 water sensors. The water comes in from the forward through-hull and triggers the forward sensor but then flows down the bilge triggering the other two. If you looked at an ordinary system this would simply show water in all three sections but with my idea it would state that the forward sensor alarmed first and so you could direct your search there.

It may also be possible to fit a sensor to through-hulls so that you can see the flow of water through them. i.e. while underway you could see that water is going through the engine intake through-hull but all the others are fine. If the pipe falls off then you could see that water is going through that particular through hull that it shouldn't be.

Is this all too complex?
 

Graham_Wright

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Sticking to the subject of sinking I was thinking that most people, while underway, are completely unaware that they have a breach in their hull until such time that the cabin sole is awash. At this point valuable time has been wasted and also it is much more difficult to identify the source of the leak or even if it comes from forward or aft. I was thinking that there must be or should be a device that can monitor the bilges and immediately warn of water but also to remember the order in which the bilge filled. So, for instance, the bilge divided into 3 sections with 3 water sensors. The water comes in from the forward through-hull and triggers the forward sensor but then flows down the bilge triggering the other two. If you looked at an ordinary system this would simply show water in all three sections but with my idea it would state that the forward sensor alarmed first and so you could direct your search there.

It may also be possible to fit a sensor to through-hulls so that you can see the flow of water through them. i.e. while underway you could see that water is going through the engine intake through-hull but all the others are fine. If the pipe falls off then you could see that water is going through that particular through hull that it shouldn't be.

Is this all too complex?

Celectron.
 

pmagowan

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Yes! although not difficult to have sensors on bilge areas. automatic bilge pumps do that for you.

One can get obsessed with worrying about what might happen - but rarely does.

The thing is that if one worries about it at the design stage then one might never have to worry about it again! :)
 

Twister_Ken

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Sticking to the subject of sinking I was thinking that most people, while underway, are completely unaware that they have a breach in their hull until such time that the cabin sole is awash. At this point valuable time has been wasted and also it is much more difficult to identify the source of the leak or even if it comes from forward or aft. I was thinking that there must be or should be a device that can monitor the bilges and immediately warn of water but also to remember the order in which the bilge filled. So, for instance, the bilge divided into 3 sections with 3 water sensors. The water comes in from the forward through-hull and triggers the forward sensor but then flows down the bilge triggering the other two. If you looked at an ordinary system this would simply show water in all three sections but with my idea it would state that the forward sensor alarmed first and so you could direct your search there.

It may also be possible to fit a sensor to through-hulls so that you can see the flow of water through them. i.e. while underway you could see that water is going through the engine intake through-hull but all the others are fine. If the pipe falls off then you could see that water is going through that particular through hull that it shouldn't be.

Is this all too complex?

That sounds like an ideal solution for, let's say, a home-built wooden boat with a home-cast keel where the owner/builder doesn't have confidence in his ability to produce a water-tight structure! :rolleyes:
 

pmagowan

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Celectron.

Just had a look at that and it seems more designed for when you are off the boat to monitor pump activity although it could be used in the way I envisage. It might be a wee bit clunky in an emergency situation as you would need to scroll through all the pumps and there would need to be a greater than 1 minute interval between one pump and the next activating for it to record the sequence.
 

pmagowan

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That sounds like an ideal solution for, let's say, a home-built wooden boat with a home-cast keel where the owner/builder doesn't have confidence in his ability to produce a water-tight structure! :rolleyes:

Lack of confidence is not a problem I suffer from! :)

I don't know of any boat where one can be assured of its ability to remain watertight in all circumstances. Something simple like a hot day while motoring softening a pipe on the throughhull that then pops off when you bash over a bow wave from the fast ferry. Or an electrical fault at the marina causing excessive corrosion weakening a throughhull. Or a faulty throughhull etc etc. I am not sure any of us can be confident that these type of things might not occur.
 

BruceDanforth

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I think you are making things too complicated. Why not consider a design with a soddin' great pump that will clear water fast if it gets in and an interior that gives you fast accessibility to the hull if needed - furniture/panels that come out quickly? You might detect your leak quickly with technology but then have to tear the inside of your boat apart with a crowbar in a state of terror. Through hulls not in use whilst sailing should be closed not monitored.
 

Stemar

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Assuming sea water, rather than fresh, all that would be needed for a sensor would be a couple of contacts with an air gap of 1mm or so. When the resistance suddenly drops from gigaohms to kilohms, you've got problems. (not sure of the resistance of sea water, but it wouldn't be hard to find out the necessary prefixes)
 

Ripster

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Bilge alarm - very common as has been said, often linked to a bilge pump with a float or electric contact switch. You can have as many as you want I guess all over the boat.
 
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