Ice
Accretion
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on the thumbnail for a larger image
Working
North in Winter months is dangerous because of the chance of
your vessel icing
up because of ice accretion
There are several reaons for ice accretion, these are;
(1)
Spray hitting the vessel with the air temperature being at least
minus 2o.
(2) Fog freezing on the structure of your vessel.
(3) Rain Freezing on the structure of your vessel.
(4) Seas entering your vessel and freezing up.
(5) Fresh water leaking or being discharged from a pipe on your
vessel.
If
your vessel starts to ice up through ice accretion then do the
following;
(1)
Turn the vessel around and head South toward a warmer climate.
(2) Minimise the spray coming onto your vessel by slowing your
vessel down
(3) If your vessel is listing to starboard, then take the ice
off the port side first, you'll give your vessel a bigger list,
but the centre of buoyancy will move out also and thus you will
have a bigger righting lever.
The Law states if you encounter ice accretion on your vessel
that was not issued with the shipping forecast, you must;
(1)
Inform all ships in the area
(2) Contact the Coastguard
Ice
accretion can occur as far South as 57o North, in
the 1990's several fishing vessels working out of a fishing
port called "Fraserburgh" encountered ice accretion.
Never
ever take chances with ice accretion, this can and will severely
affect your vessels stability, vessels have capsized because
of the ANGLE OF LOLL effect that ice accretion has on the vessel,
the vessel will become top heavy as the Centre of Gravity nears/meets
of goes above the Metacentre. (The vessel with have an UNSTABLE
EQUILIBRIUM).
Iceberg's
  
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larger image
Statistics
show that 9/10 of an iceberg is below the surface of the water;
Icebergs are easily detected by radar, but caution must be taken
for BERGY BITS (small icebegs broken off from a Glacier, or
GROWLERS which are smaller than BERGY BITS and harder to detect
by radar.
Growlers are a Berg that is less than 17 feet above sea level
and not more than 50 feet in diameter
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