(Extracts courtesy of A.N.T.A. publications, Ranger Hope © 2008



Marine casualties 

Grounding & founder  

Loss of rudder/propulsion   

Person overboard  

Assisting vessels in distress 

Principles of stability

Obligation to persons on board





Marine casualties



Collisions must be avoided - as rule 16 of the International Collision Regulations states - every vessel, which is directed to keep out of the way of another vessel, must take early and substantial action to stay clear.


Collision Imminent

Whatever action you take, it should be to prevent contact, however if collision is unavoidable you should reduce damage to ‘sensitive’ areas of both vessels.

Reduction of damage can be achieved by:-

-  Taking speed off the vessel (full astern, etc).

-  Attempting to avoid by turning the vessel (a glancing blow rather than a direct contact). A bow to bow situation or bow to quarter situation will be far less damaging that the bow cutting directly into the other vessel's hull, particularly near the engine room compartment.



Actions to take after collision

§         sound emergency muster alarm – (7 short, 1 long)

§         stop the vessel

§         transmit distress or urgency signal on the radio (if necessary)

§         evacuate passengers and crew to emergency stations

§         ensure all people are accounted for and check for injuries

§         ensure the safety of the vessel and all on-board - Master's responsibility

§         determine the extent of damage

§         sound tank/s

§         inspect bilges or sound if enclosed

§         observe for any oil, or fuel spills in the water around the vessel.


If damage has occurred take damage control measures:- (refer to ‘foundering’ section)


§         prepare lifesaving equipment

§         prepare to abandon (if situation deteriorates).


With situation controlled:

If assistance from other vessels is non-existent and the vessel looks like foundering with a coastline nearby, consider ‘beaching’ the vessel.


if the collision between the two vessels has resulted in the vessel piercing the other and becoming wedged, the striking vessel should refrain from going astern immediately, as this may result in one or both vessels' sinking. If abandonment of either vessel is essential, transferring to the stable vessel, while wedged, may be easier than by doing so via water.






Groundings & founder


Grounding of a vessel can be an intentional situation or occur accidentally.

There are three different types of grounding; e.g. beaching, stranding, or grounding.




A vessel may be beached for many reasons, maybe to save it from foundering in deep water or to flood her, at a recoverable location, in the event of an uncontrolled fire, or simply to carry out underwater repairs, inspections, or cleaning of a foul bottom.


Points to consider (during beaching):



§         attempt to refloat as soon as vessel reaches flotation draft, remove ballast if it was added - maintain an even trim

§         bleed cooling systems

§         use anchors to kedge the vessel.


Stranding or Grounding

Stranding is the accidental grounding of a vessel on a beach or shoreline while grounding is the accidental contact with the sea bed other than the shoreline.

Actions to take (accidental stranding or grounding):

§         sound the alarm to muster the crew/passengers (7 short, 1 long)

§         account for all personnel and check for injuries

§         stop engines and auxiliaries if grounding is severe

§         sound bilges and inspect void areas

§         take bearings and plot your position - then attempt to determine reason for grounding from the charts

§         survey the area around the grounding (from chart)

§         determine the tide and tidal stream

§         check weather predictions for the area

§         sound around the vessel to determine the extent of the grounding

§         check for hull damage (if severe damage has occurred, it may be best to stay grounded)


With a partial grounding:

§         move passengers and crew to lighten the grounded section of the vessel, jettison any weights possible

§         use astern power sparingly, pay attention to the pumping of mud/sand under the keel due to excess astern propulsion.

if rocky - astern propulsion can damage the hull lay out anchors to assist in refloating or preventing vessel going further aground

§         request assistance (if necessary). consider a tow

§         display appropriate signal `vessel aground'.

When refloating, use anchors to kedge, if the engine's propulsion is insufficient to refloat. Move weights as necessary, have lifesaving appliances ready in case of sudden need. Commence refloating just prior to high tide. If the bottom is sand or mud a vacuum may be created between the hull and the sea-bed. To break this suction it may be necessary to "waggle the vessel's tail" by use of the weights or pulling on alternate anchors.

Once clear of the obstruction it will be necessary to again check the vessel for any damage or ingress of water. Also check propulsion and steerage systems and engine cooling systems.

Note events in vessel’s log or record book and report incident to the authorities.

If grounded on a reef at an uncertain location it may be prudent to stay grounded and adding ballast to prevent further damage to the hull due to movement of the vessel on the grounding.



Foundering is the adverse effect on the vessel's buoyancy due to the ingress of water resulting in sinking.

Foundering could be the end result of a collision or any situation causing hull damage or water ingress.

Action taken (to prevent foundering):

When collision or damage assessment drills are undertaken, the first concern is the ingress of water, which if left unchecked, could lead to the vessel's foundering.

To prevent this, several steps can be taken:

  If the vessel is bilged the holed compartment should be, if possible, isolated by closing watertight doors or openings and the section pumped out. If the pump cannot contain the flooding other means may be needed to reduce the intake of water.

  Listing the vessel, especially if the damage is near the waterline, will reduce the flow of water into the vessel. This can be achieved by moving weights or ballasting.

Thought may be given to the use of any possible material to plug up a hole. This could include pillows, bedding, cushions, mattresses etc.

"Collision Mats" could also be incorporated. This is usually a  strong piece of canvas with spars secured on two opposite sides. The mat is usually rolled up and the lines led under the hull until it is near the hole and then unrolled effectively sealing the holed area and reducing the flow of water into the compartment.

NOTE:- If spars are not used the water pressure may prevent the `tarps' (collision mats) from fully covering the holed section.

There are commercially manufactured `collision mats' for small craft. These are of the umbrella principle. The unit is pushed through the hole then opened around the area by pulling on the centre pole.


Collision Mats are designed to reduce the ingress of water to a level where the pump discharge is of a greater capacity than the flow of water into the vessel.


Once control has been gained, more permanent repairs can be undertaken.

If a vessel has sustained damage to it's bow section or a compartment which leaves a bulkhead exposed to the sea, support must be given to these particular areas. The water pressure on the bulkhead will increase dramatically once the vessel gets underway - without support more damage may occur resulting in loss of the vessel.


Partially or Completely Disabled

If due to an incident, whether it be a collision or grounding, the vessel is left in a state such that assistance is required, consider the following:

§         determine ‘if’ and ‘what’ dangers there may be to crew or passengers

§         deploy a sea anchor (drogue) to bring the bow into the wind or tide. This reduces the movement and possible injuries

§         notify the safety authorities of your situation and position

§         display appropriate lights or shapes and sound signals generated if necessary

§         maintain an adequate lookout until the situation is corrected

§         consider alternative means of propulsion/steerage, etc. to get under way

§         consider a tow and prepare vessel accordingly (check the rules for salvage and if possible obtain a tow from a vessel of the same company or nationality)




Loss of rudder/propulsion

If the vessel experiencing rudder loss is a twin screw then the problem is lessened.  Use can be made of the revolutions of each engine to control the direction of the vessel. 

In a single screwed vessel, a different situation applies and can best be met by towing an object offering drag such as:- fish basket, bundle of nets, a 20 litre partly filled drum or bundles of boards attached to a length of line.

When secured to the centre of the transom, this arrangement will keep the vessel moving in a straight direction.

To steer the vessel it will be necessary to attach the line (with the drag attached) to one quarter of the vessel, with a lighter line made fast to the other quarter.

Alteration of tension on the light line will cause a change in direction of the vessel.

If the rudder has been lost it must be remembered that there is a good possibility of ingress of water into the vessel via the rudder post area. Make sure the area is secured.

If the rudder is in place but damaged, use knotted chain or rope across the trailing edge to position and secure in midship position.  Some rudders will have an access hole for lifting gear. This could be used to hold shackles and enable the rudder to be tied off.

With the use of the rudder and failure of the mechanical or hydraulic drive the situation is different. 


Action to take (single propeller):

§         sound alarm

§         stop engine (consider anchoring or sea anchor)

§         check cause of failure

§         remove covers (if fitted) and fit emergency tiller

§         fit operating tackle and tie off

§         once secure, remove the hydraulic or mechanical actuating mechanism and secure clear of the tiller or rudder stock

§         rig operating gear so that you have a clear view from the steering position.

Be aware of the consequences of astern propulsion while in emergency steering mode. The action of the water being drawn across the blade will place more load on the operating lines and could cause the lines to be pulled through the hands (if hand operated).

Operation of the twin gear for single rudder can be achieved by one person if a drum is mounted with the running part of the tackle from the two units being wound in the opposite direction around the operating drum.

Don't forget when steaming in this manner to display "Restricted in Ability to Manoeuvre" lights and shapes and record events in vessel’s log.



Loss of Propulsion

§         sound signal

§         stop engine

§         determine the extent of damage


has the propeller been lost?

has shaft broken?

is there any water ingress through stern tube?


§         send the appropriate signal - usually in this case an urgency - "Pan Pan" should suffice

§         request assistance if propulsion is lost

§         display the "Not Under Command" (NUC) signal.


Propeller Fouled or Damaged

A fouled propeller can often be cleared. The course of action will depend on the type and severity of the fouling.

A line or net entwined around the propeller or shaft may be cut free. Heavy fouling such as wire rope or chain may call for a more detailed operation which could include ballasting or shifting weights to raise the aft end of the vessel to enable work to be carried out and the use of cutting equipment to remove the fouling.

Have an observer for the person undertaking the work at all time.

Display the appropriate signal (NUC).

After the obstruction has been cleared and people are out of the water and clear, turn the propeller shaft manually and feel for any drag prior to starting engine and engaging transmission. Start engine and check for any unusual noises or vibration in the propulsion system.

Power on gradually and monitor area for any vibration, heat, noise and or leaks through stern gland. It could be possible that the aft bearing or propeller may have sustained damage.

Damaged Propeller

This may be caused by fouling, striking an object in the water, other equipment failure or partial grounding.

Problems associated with a damaged propeller can usually be detected by noise or vibration through the vessel.

If you feel a thump and vibration commences, there is a good  chance that you have struck something and damage has occurred in the propeller region.

If the vibration occurs and there is noise from the aft end of the vessel, it could be the propeller loose, fouled or even rudder damage causing interference with the propeller.

With any possible damage to the propulsion system, the action to take will be:-

§         sound the alarm

§         reduce engine speed and attempt to determine the cause of the problem

§         ensure water tight integrity of the vessel

§         if at reduced speed the problem still exists, shut down engine, lock `out', and visually inspect the propeller region for damage.

The inspection result will determine the next course of action, whether it is safe to proceed at reduced speed, repairable, or a tow is required.

Display signals NUC.





Person overboard


This is a situation where the person is seen going over the vessel's side. A person overboard situation should never occur if procedures are carried out correctly.


If a person does fall into the water:

§         throw a lifebuoy (as far as possible to the person) or any other flotation device

§         yell out "man overboard" and the side to which he/she fell maintain visual contact or have an observer take over the roll, point to the person in the water

§         warn other vessels in the vicinity of the situation ‘o’ flag


The helmsman on receipt of a "man overboard" signal will first acknowledge the call (if plotter is fitted - hit the "man overboard" key to indicate the position) take the appropriate turn depending on type of vessel and operation undertaken - always take the propeller away from the person in the water. The appropriate action may be to stop the vessel and allow the person to swim to the vessel


§         bring vessel back near the person, approach the person from downwind, keeping the bow into the wind as this enables maneuvering at slower speeds

§         notify the crew of the pick up side of vessel

§         stop vessel when person is near the beam section

§         retrieve the person by means of rescue quoit and line, or nets over the side, boarding ladder, Jason's cradle, or litter, ensure propeller is not operating with the person alongside.


When the person is retrieved, it may be necessary to support the person when he/she reaches the safe place. Ensure the person remains out of harm's way.


Types of turns (for the recovery of a person overboard

For small craft a 'Y' turn can be adopted. This turn involves turning the helm hard over (in the direction of side person went over). Stop the engine and full astern (with helm still hard over in same direction then full ahead with helm still in same place) then slow and straighten near to person in water, stop near person.


Two other commonly used turns are:


(a) The Elliptical Turn:-

On notification that a person has fallen overboard, the helmsman should turn the wheel hard over on the direction to the side which the person fell overboard. At the same time they should note the compass course 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 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 not operating as the person is brought onboard.

(b) The Williamson's Turn:-

This is the most popular turn due to its ability to be used for most situations eg, 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.

If notified that a person has fallen overboard, the helmsman should turn the wheel hard over in the direction to the side which the person fell overboard. At the same time they should note the compass course they were on prior to the man overboard (Position 1).

The wheel should be kept hard over until the vessel is 60* off its original course (Position 2). The wheel should then be put hard over on the opposite direction until the vessel is on its reciprocal course (Position 3).

The vessel should then be straightened up to follow the reciprocal course, slow down and then retrieve the person, given the sea and wind conditions. On retrieval, the vessel should be stopped and the propellers not operating as the person is brought onboard.

It should be noted that to get to Position 2 it may be between 60* and 70* off the original course. To establish the figure for your vessel it will be necessary to treat man overboard situations working between 60* and 70*.


Person missing

A person missing situation is one in which a person is lost over the side but unnoticed doing so. The problem with this situation is that the time period for the person in the water can only be estimated. The most appropriate action in this instance is to use the Williamson's Turn and back track along the original course for the period of time from when the person was last seen.  You may have to take into account the vessel's leeway but drift should be similar for both vessel and person.

At night use search lights and have people listening for cries of help (engines should be slowed/stopped periodically for this purpose).


Searching for a person overboard


(a)  Expanding square system

This system starts at a point closest to where the person was observed, original mark on the plotter would be used. The diagram shows the pattern, distance between the tracks will depend on height of lookout and weather conditions but should be such that each sweep should double up on detection.

  (b) Sector searching

If the particular incident position was noted and the conditions indicate that the person may not have drifted far from that particular point, the sector search pattern may be used. Remember with this turn all changes in course are 120* to starboard.

If the person has not been detected on completion of the first search, adjust the original line by 30* and recommence the search pattern. Distance for each leg will vary for types of vessels but may be 1-2 nautical miles.





Assisting vessels in distress

Section 265(1) of the Navigation Act, 1912 requires the Master of a vessel to render all possible assistance to any persons from or on a vessel or aircraft that are or the Master has reason to believe are in need of assistance.

However, there are a few points that need further clarification. Your position may be 300 miles away - too far to be of practical assistance - but you may be the only vessel that has picked up the distress signal. You are required to maintain that contact, inform a coastal radio station or, if that is not possible, some other vessel that may be closer, and continue to act as a relay station for as long as required.

Your obligation to render all possible assistance is only lifted when the distressed vessel advises you that your assistance is no longer required, either because others are already there or some other satisfactory arrangement has been made. This same release may be obtained from the Master of another vessel which has reached the area or the relevant search and rescue body that has taken charge of the operation and has the situation under control. You should read the relevant section of the act very carefully.


Limits of responsibility

The primary aim of a Master of a vessel rendering assistance is saving life.

In achieving this aim the best option may be to take the vessel in tow or, in some other way, save it from total loss. The action taken will depend on the circumstance of the case that he/she is faced with - but there is no legal responsibility on the Master of the rescuing vessel to save property.


Calm water transfer

This brings us to the methods by which personnel may be transferred from the distressed vessel.

In very rare instances it is possible to go alongside, but this presupposes calm seas and the fact that the vessel is not on fire. Even then, the swell on an otherwise calm sea can cause the two vessels to come heavily together with considerable risk to those being transferred as well as to the vessels and rescuers themselves.

As the circumstances in a situation like this are variable, no set method of rescue can be decided upon without first examining the circumstances and making a professional judgment based on your knowledge gained in this course and practical knowledge of the capabilities of your vessel. Only you can decide the best course of action to facilitate the safe rescue of the other vessel’s crew and passengers and the safety of your crew, passengers and vessel.

If circumstances allow you to go alongside the other vessel, ensure that all booms, boats and movable gear are swung inboard so as to avoid getting tangled or damaged, and see that the same precautions are taken aboard the other vessel. Position the heaviest fenders you can muster along the vessel's side at gunwale height along the points of the vessels side that will come into contact with the other vessel, judging from its shape, etc. Do not fasten your vessel to the stricken vessel as the circumstances of the other vessel may change suddenly, jeopardising the safety of the whole operation.  Maintain your vessel's position utilising her engines, backing off and coming back again as often as necessary until the operation is completed.

The other option available is to position your vessel a safe distance away from the stricken vessel and lower a boat (if your vessel is fitted with one) and transfer the personnel.


Rough water transfer

Rough weather presents a totally different picture, and you will usually have to combine ingenuity with good seamanship if the transfer is to be effected safely.

To begin with, the size of the boat usually carried by a vessel of 12 metres is probably too small to be launched safely in rough seas.

In this sort of heavy weather operation, one thing that does work in our favour is that both vessels will lie unattended beam-on to wind and sea and, if they are of reasonably similar size, their downwind rate of drift will be much the same. If this is so, you can position yourself up-wind and beam-on to the other vessel, and thereby create a lee of some sort between you.

  If you have a line throwing gun, a line can now be passed.

Once this is done, you have made physical contact, and there are several ways in which the line can be put to use. This will be discussed shortly.

However, few small vessels carry such equipment and it would be exceedingly dangerous under the conditions visualised to go close enough to use a heaving line.

This means you have to devise some other means of getting the line across. Floating it down on a lifebuoy or similar flotation device is usually doomed to failure as the buoy, with no windage, will probably drift at the same rate as the vessels, even if the line attached to it is very light.

Perhaps the best flotation instrument is an inflated rubber raft which will blow rapidly downwind, taking a light line with it (light enough to not prevent the raft from drifting, but heavy enough to haul it back fully loaded).

The distressed crew can then board this raft and be hauled back to you on this line. This also means that injured personnel can be transferred fairly easily.

Also remember that a very small amount of oil has a miraculous calming effect on the sea, but to be successful in the situation being discussed it must be released from the distressed vessel. ( both vessels are drifting down-wind on a sea surface that has no lateral movement, so the apparent drift of the oil will be up-wind.)

If you do not have an inflatable raft, your ingenuity may be able to devise some other means that will have the necessary windage - a small unmanned aluminium dinghy, for instance.

Another method of transferring a line, and which requires a nice piece of vessel handling, is to tow a buoyed line across the bow or stern of the other so that it can be recovered by the other vessel with a boathook as it streams past.

Whichever way you do it (except for the raft method, which is self sufficient for the whole operation), you now have a light line between yourself and the other vessel. This can now be used as a messenger to  carry a heavier line.

There are several ways in which this heavy line can be used to bring the survivors aboard.

(a)  They can inflate their own life raft and be towed across in the raft, or perhaps use their dinghy in the same way. They should all be wearing life jackets for this operation, as there is an extra hazard of falling into the sea when climbing aboard at your end. If they are using a dinghy it might easily swamp on the way over. (This is where oil can be of inestimable value, smoothing out the breaking crests of big seas and reducing the danger of swamping.)

  Where neither raft nor dinghy is available, the survivors can be towed across a few at a time in the water and supported by their life jackets. This is made considerably safer if life buoys are tied to the tow rope.

  There are possibly other ways which your ingenuity can devise based on the same general principles.

One last very important point -

Unless all survivors come across in the first haul, however it is made, it is essential that a messenger line, secured to the rope or raft, is paid out from the distressed vessel to haul it back for the subsequent trips. The last thing you need at this stage is to have to repeat the process of passing that initial line.


Taking in tow/salvage

It is not intended here to go into the details of towing methods and the procedures involved in passing, securing and carrying out the tow.

There are, however, several points you should consider before taking any vessel in tow under these circumstances.

  As has already been mentioned, this may be the best and safest method of effecting a rescue - that is your decision - but it is in no way incumbent upon you to do so, and the safety of your own vessel and her personnel must be your first consideration.


Before passing a tow you should:

With regard to (vi) above, this may be done between the owners ashore or between yourself and the Master of the distressed vessel.





Principles of stability

Stability is the ability of a vessel to return to the upright when heeled by an external force, eg. wave action, wind, etc.

Any person taking a vessel to sea must have knowledge of the vessel's capabilities and limitations. One of the primary considerations is the stability of the vessel, knowledge of what factors can make the vessel less stable or even unstable and therefore unsafe, is essential.

The Coxswain of a vessel has the ability to change the status of the vessel's stability by his/her action alone. 

The stability of a vessel depends upon the position of the vessel’s “Centre of Gravity”, the Centre of Gravity (G) is an imaginary point on a vessel through which the entire weight of the vessel is said to be acting vertically downwards. If the G is high on the vessel this would cause the vessel to be less stable than if it were low down in the vessel. If the G is raised considerably it may lead to the vessel being unstable. This means that if the vessel were heeled by an external force, it would not return to the upright condition but would capsize.

The position of the vessel’s G depends upon the distribution of the weights on the vessel. If there are a large number of weights high up on the vessel, for example, a number of 44 gallon drums of lube oil stored on top of the wheelhouse, this would cause the G to be raised reducing the stability of the vessel. Another example would be the entire passenger and crew complement on the Fly bridge whale watching!

On the other hand, if the weights are stored, low down in the hold of the vessel, it would increase the stability of the vessel. 

The position of your G also dictates the comfort of your crew and passengers on a voyage. If your G is very high on the vessel it would cause the vessel to roll at the slightest hint of a wave and furthermore, if in rough weather, may not return to the upright condition before it is struck by another wave and caused to capsize. 

It is important to remember that if you are removing a weight from a lower part of the vessel this will also cause the G to rise and reduce stability for example: using fuel from a low tank.

On the other hand, if your vessel’s G is very low it would cause the vessel, if heeled, to return to the upright very rapidly, making it uncomfortable for the crew and passengers and also putting excessive strain on the hull and equipment mounts. This type of vessel is known as a “Stiff Ship”. The opposite of a stiff vessel is a “tender vessel” that has a high G and tends to roll in the slightest seaway.

To remedy a stiff ship you must move weights on your vessel upwards or get rid of weights from down below. These weights could be in the form of cargo or ballast water etc. Always take care not to raise the G so high as to create a tender vessel. Vice versa, in a tender vessel, weights will need to be lowered or added as low within the hull as possible.

For the above reasons, it is essential that the Coxswain be aware of the positioning of all the weights on his/her vessel and get the “feel” of how the vessel handles in a seaway. It is also paramount to ensure that the overzealous passengers do not all rush up to the Fly bridge and over to one side in order to obtain the best video footage of the sights around.

Another factor that contributes to a reduction in a vessel's stability is “free surface effect”. This is caused by the movement of liquid in any compartment on the vessel. It can occur due to half full fuel, water or ballast tanks or water in the bilges. This effect reduces the vessel’s stability, due to the fact that the weight of the liquid is shifting from side to side and this causes a shift in the G of the vessel towards the side the vessel is heeled, reducing the forces that return the vessel to the upright position.

Overloading of the vessel is also a considerable problem and small vessel not having “load lines”, it leaves the amount to be loaded to common sense. It is essential to maintain an adequate distance from the waterline to the deck (Freeboard), as this is what gives the vessel its “reserve buoyancy” and the ability to ride out a seaway. 

In summary, keep weights on the vessel as low down as possible, evenly distributed and well secured, keep your bilges as dry as possible without infringing pollution laws. The vessel should be loaded in a manner so as to have the vessel trimmed by stern (where the vessel sits deeper in the water at the after part than the fore part). This enhances the sea handling capabilities of the vessel, affording steering and handling efficiency plus optimum use of the thrust generated by the propeller. Also always keeping a watchful eye on the passengers disposition in order to prevent a dangerous “list” or trim by the bow, which could cause the vessel to become less or even unstable and possible swamping of the vessel.



Obligation to persons on-board

The Master has an obligation of duty of care under the relevant Federal and State/Territory Workplace Health and Safety Acts to persons on board the vessel. This duty is also included in relevant Federal/State/Territory Marine Acts that require the Master to operate the vessel safely and in a seaworthy condition and that it meets the survey requirements of the relevant authorities.


As Master it is your responsibility: