In the event of 'man overboard', appropriate action is taken to manoeuvre the vessel and to deploy survival equipment.
This is a situation where the person is seen going over the vessel’s
side. Person overboard situation should never occur if procedures are carried
out correctly.
If a person does fall into the
water
• yell out “man overboard”
and on which side.
• swing the stern clear of
the person overboard & select GPS MOB save.
• throw a lifebuoy or any
other flotation device.
• maintain visual contact,
point to the person in the water.
Conscious-
using a rescue quoit and line, or nets over the side, boarding
ladder.
Unconscious- consider
using a lifeboat, ensure propeller is not operating with the
person alongside. If operating in, northern waters during stinger
season take extra precaution when recovering the person.
Turns (to recover of a person overboard):
The best
turn is the quickest for the characteristics of the vessel and the situation.
Small craft a ‘Y’ turn- This
turn involves turning the helm hard over (in the direction
of side person went over). Then stopping the engine and then full
astern (with helm still hard over in same direction then full ahead with helm
still in same place) then slow and straighten near the person in water, then
stop near person.
The Elliptical (Double) Turn- On notification that a person has fallen
overboard, the
helmsman should turn the wheel hard over in the direction to the
side that the person fell overboard. At the same time the helmsman should note
the compass course that
they were on prior to the man overboard (position 1).
The wheel should be kept hard
over until the vessel is on the reciprocal course (plus 180°) and then
straightened up to follow this straight run until about 30° abaft the person in
the water. The wheel should then be turned hard over in the same direction as
before until back on the original course. An assessment should then be made as
to how to retrieve the person, given the sea and wind conditions. On retrieval
the vessel should be stopped and the propellers stopped as the person is
brought onboard.
The
Williamson’s Turn- This is
the most popular turn due to its ability to be used for
most situations e.g. person overboard, person missing, large
vessels, small vessels, rough or calm water. It is a turn, which takes the
vessel back along its reciprocal
track.
The wheel should be kept hard over until the vessel is 70° off its
original course. The wheel should then be put hard over in the opposite
direction until the vessel is on its reciprocal course.
The vessel should then be straightened up to follow the reciprocal
course, slow down to retrieve the person, given the sea and wind conditions. On
retrieval, the vessel should be stopped and the propellers stopped as the
person is brought onboard.
It should
be noted that to turn away from the person in the water may be between 60° and
70° off the original course. To establish the figure for your vessel it will be
necessary to practice man overboard situations.
Retrieving personnel from the water:
When the person is sighted the Master must then consider the best
method to bring the person onboard. This exercise could be as easy as stopping
the vessel to let the person swim up to and climb aboard or launching a boat to
pick the person up. If your vessel has a large freeboard it is definitely going
to restrict your options when recovering a person from the water. Vessels with
a small freeboard have more options.
Vessels with small freeboard- If the person is conscious you could manoeuvre
the
vessel
close to the person and then assist them aboard by helping them climb over
the
gunwale. If they are weak from the
ordeal or unconscious it may be necessary to
rig a rescue net or Jason’s Cradle. Both these devices are lashed
on the inboard side of the boat and the outer side is held away from the vessel
side allowing the net or
cradle to
form a hammock in the water.
To get the person onboard, manoeuvre them into position, with
their legs at the bow end of the vessel, going head first into the sagging net
that is in the water. This allows the person to be positioned in the net,
without an arm or leg being left out of it. Once in position you gently heave
on the outer side of the net/cradle and the person will come inboard. It is
essential to be extremely cautious while doing this as the person in the net
may be injured as a result.
The above method is also extremely helpful when retrieving persons
that are suffering from hypothermia as in this fashion all parts of the body
clear the water at the same time and “Hydrostatic Squeeze” is eased off the
body simultaneously. If a person suffering from hypothermia is lifted out of
the water vertically the loss of the “Hydrostatic Squeeze” and the effect of
gravity would cause the blood to rush to the legs causing a loss in blood
pressure and collapse or further complications for the casualty. See your
Module on “Occupational Health and Safety” for further information.
Vessels with large freeboard- large vessels should rig guest warps at their
waterline from bow to quarter
(allowing survivors to clutch on) and approach so as to create a lee for those
in the water. It may need to launch its lifeboat or rescue boat to facilitate
the rescue. If a boat has to be launched manoeuvre the mother vessel to create
a lee for the launch and rescue. Always be aware that your vessel will drift
rapidly towards a person in the water if you stop manoeuvring, due to the
vessel’s
greater
windage than a body in the water.
To calm the sea, oil may be spilt
on the windward side of the person in the water so that it drifts down to them
as the rescue boat approaches so as to make it easier to pick the person up. To
get the person into the boat from the water, a rescue net or Jason’s Cradle may
be used.
If launching of your vessel’s
boat is not an option, a scrambling net could be draped over the vessels side
dangling in the water, to enable the persons in the water to climb up. It may
also be possible to use a vessel’s crane or boom with a cargo net attached to
it. Once this is dangled in the water the survivors can climb onto it and be
hoisted out of the water.
Rescuing persons from a vessel in distress or
from a wreck:
When a vessel is sinking liferafts/boats are not always for
abandoning the vessel. Passengers and crew should therefore stay aboard the
stricken vessel (if possible) until a rescue vessel arrives and sends boats
across to the disabled vessel.
In calm weather it may be
possible to go alongside. However, this would be rare as even in calm seas the
swell could cause the two vessels to come heavily together. Damaging the vessels
and possibly risking the lives of those being transferred. It would usually be
better to lower a boat and transfer the personnel.
If the sea is rough the rescue vessel should launch a rescue boat
from a position slightly upwind of the stricken vessel. It would assist the
operation if both vessels distribute oil to help calm the seas. A disabled
vessel would usually lie beam on to the wind and in some circumstances it would
be advantageous, (providing that the seas are not to big), to launch the rescue
boat from her lee side while lying stopped in the water to windward of the
disabled vessel.
In other circumstances the best method may be to launch while
slowly motoring ahead with the wind about 2 points on the bow. This would
create a lee for the rescue boat without the danger of excessive rolling.
In extreme conditions it maybe
too dangerous to use boats and the most effective method to transfer the
personnel is to haul a liferaft between the two vessels. A line can be passed
to the other vessel by using a rocket line or if not available. With the rescue
vessel positioned upwind a liferaft can be released and the wind will take it
rapidly down to the disabled vessel. The line attached to the liferaft should
be strong enough so that the raft can be hauled back fully loaded. The life
raft can then be hauled from one vessel to the other by a strong rope.
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