Keeping afloat after colliding with a waterborne object
The risk of colliding with a floating or waterborne object such as a whale, tree or a freight container is very low. Sadly marine experts believe two centuries of whaling may have reduced whale numbers to 1% of the original population. There are now believed to be as little as 10,000 humpback whales in the North Atlantic were 240,000 roamed (1.5m worldwide). Meanwhile the seas have become crowded with commercial shipping. Some countries in 2007 are increasing the number of ships in their fleets by 20% a year. There will be 7,000 container ships on the sea in 2008, the largest carrying 10,000 x 20ft container stacked 18 layers high on their decks. This increases the likelihood of container collision. Container collision sounds strange but piled high as described they fall off ships. Whilst some containers sink, others float just below the surface, depending on the buoyancy and packaging of the cargo they contain. The risk of colliding with a container is higher in busy shipping lanes and during winter and spring when storms make it more likely that containers are washed overboard from freighters. The problem with waterborne objects is keeping a look out for them. As they often reside just below the surface it is not practical to place a watch on the bow for days on end and they are completely imperceptible at night or in high seas.
Safety bilge pump
Most yacht bilge pump arrangements are one manual pump operated from the cockpit and a central electric pump. These do not lend themselves to enduring extreme conditions where a vessel has elected to adopt a battened down strategy.
Avoiding bilge pump blockages
Bilge pumps can suck up floating debris in the water causing them to block and fail.