[PUP] Bilge Pumps

[Peter Sheppard]

Quite a lot of discussion and research has taken place on the Nordhavn 55
weblog about bilge pumps.
I have come to the conclusion so far that bilge pumps will only buy you some
time while you get to the core of the problem and that is stopping the
source of the flooding. I'm advised that most problems will get down to
hoses coming off a  thru hull giving away, and we have valves to close off.
If the actual skin fitting gives way which I can't imagine likely, but we
should all have conical plugs to hammer in, as well as many other devices
available in my damage control kit
If we have a breach caused by hitting something serious like a sharp bommie,
and low down below the water line, we are in big strife because flooding
tables show that bilge pumps are going to struggle big time, and a hole 1'
below the water line will in no time become 3' or 4' down in no time,
increasing dramatically the ingress pressure.
I am having a collision mat made, and the design will be that it will have
enough lines secured to stop it peeling off the hull when underway. This
will probably take some real life testing to perfect the design. Anyone that
has been down this track maybe can offer some advice.
I am also purchasing a portable gas (or diesel) fire fighting pump that can
be selectively deployed to either of the four compartments that make up the
bilges, and to support the current 3 pumps (2 electric and 1 manual). Limber
holes are not designed to compete with an aggresive breach.
In Australia they have an umbrella type device that can be poked through the
breach, and opened up giving a seal to reduce ingress, but I am yet to find
who makes these, so any info from the list would also be gratefully
received.
I'm certainly not paranoid about this issue because I don't plan to hit
anything, but the wilderness areas I'm going to soon is devoid of help, and
I must prepare for the unknown/unlikely/and statistically remote occurence.
Peter Sheppard