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In the event of 'man overboard', appropriate action is taken to manoeuvre the vessel and to deploy survival equipment.





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.


Make your chosen turn to recover, always take the propeller away from the person in the water. Approach the person from downwind, keeping the bow into the wind to this manoeuvring at slower speeds. Notify the crew of the pick up side of vessel. Warn other vessels in the vicinity of the situation ‘O’ flag.


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.


When notified 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 they should note the compass course they were on prior to the man overboard. 
 
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.


The rescue vessel should give as much lee as possible to the boat as it makes its way across to the stricken vessel and then position itself to leeward so as the boat can make the return journey downwind. 
 
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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