Man overboard maneuvers

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Man overboard!

The man-overboard maneuver or short MOB ( officially the gender-neutral version: man-overboard maneuver or person-overboard maneuver ) any measure includes the rescue of a man who from a vessel on the lift in the water fell. The man-over-board maneuver to be initiated immediately has priority over all other things. It is a central part of seamanship that has to be practiced again and again in practice with each new ship and each new crew.

Quick but considered action is vital. The risk of losing sight of the victim is very great. If the water is significantly colder than 20 ° C, there is also an acute risk of hypothermia , which requires a horizontal rescue, and the person must receive appropriate medical care.

First reaction

" Man overboard! “Is to be called out if a person goes overboard (together with the information on which side of the ship this happened, for example man overboard on port ! ). The driving person must be observed continuously, with the observer pointing at the person with an outstretched arm so as not to lose sight of them and to show the helmsman the direction. The shout “Man overboard!” May only be used if someone has really fallen into the water. For example, if it's just an exercise, the call is “ Buoy overboard! ".

Smoke buoy

A lightning buoy must be deployed immediately at night ; This is the only way to find someone who has fallen overboard in the dark. During the day, smoke buoys are used on larger ships with very long stopping or turning routes, which are to be thrown in the direction of the person so that they can be found again quickly and safely. Smoke buoys are also combined with a flash function.

On small vehicles with an engine, the engine is disengaged immediately and the stern is turned away from the driving person with a hard rudder in order to avoid injuries from the propeller. On a pleasure craft, the MOB maneuver is initiated immediately, i.e. the ship is turned around and driven back to the scene of the accident.

Alerting

Request for additional rescue workers

In the event of MOB, the next MRCC must be notified immediately so as not to lose valuable time while the ship's crew is making the first attempts at rescue.

The alarm is issued via distress radio (voice radio or DSC ), via an EPIRB emergency radio beacon or via the 24/7 telephone number of the MRCC Bremen via satellite phone . Transmission via the SOS button to DSC devices has priority, as this means that the exact and current GPS position is transmitted to the MRCC and - at the same time - to all vehicles in the vicinity. "Man overboard" is an emergency at sea, as there is danger to life, and is therefore announced with a radio message on VHF channel 16 with the introductory word "MAYDAY" (man overboard is not an emergency , as is often wrongly claimed). The MRCC decides - together with the captain or skipper - how to proceed, initiates the necessary measures and coordinates the rescue operation (ships, search planes, helicopters, emergency medicine). The procedures are regulated internationally within the framework of SOLAS (International Convention for the Safety of Life at Sea) in the GMDSS .

If the victim can be recovered without outside help , the MRCC must be notified immediately so that further searches can be stopped.

All ships are obliged to help save human lives and to help within the scope of their possibilities. According to international law, the expenses for this - time, fuel, aids - must be borne by each ship itself. This also applies if the search has to be terminated prematurely or after an unsuccessful search due to successful rescue by your own ship.

Alerting on large ships

On large ships, the watchman or officer on watch is notified immediately. To mark the scene of the accident, lifebuoys , life jackets or other buoyant objects of the person in the water must be thrown immediately . The officer on watch or watch officer must trigger a general alarm as soon as possible , have the MOB beacon and the Search and Rescue Radar Transponder (SART) thrown outboard, initiate a corresponding rowing maneuver (e.g. Williamson turn or Scharnow turn ) or a turning circle Inform the captain or skipper, have the machine made ready for maneuvering, press the MOB button on the ECDIS or the GPS , switch to manual control, enter the position of the accident on the nautical chart, have the emergency boat made clear and enter the accident in the ship's diary.

If there is any doubt as to whether a person has gone overboard, you must also act immediately and notify the officer in charge or the officer in charge. After immediately initiating an emergency maneuver, the latter will determine whether a person is missing by examining the passengers and crew members and, if necessary, by searching the ship.

Searching for a missing person

Example of a search procedure for IAMSAR

At 10 knots, a ship covers about 300 m in one minute. As a result, the victim is quickly out of sight even in daylight and calm seas. On large ships with a small crew, the absence of a crew member is often not immediately noticed.

Even if the exact location of the accident is known, marking with the MOB button of the GPS device only provides an approximate reference point for the search, as the person is being carried away by the current. The wind also has little influence on the person's drift . Depending on the height of the eyes and the visibility, the smoke from a MOB beacon can be seen a few hundred meters to a few nautical miles . A SART is to under favorable conditions, up to about 10 nautical miles locations .

If the person who went overboard is out of sight, a systematic search must be initiated immediately. The IAMSAR manual must be followed, which provides all the details on the search procedures to be used and the coordination of other units involved in the search.

The procedure for searching for missing persons is not part of the training for recreational boaters. They should familiarize themselves with the relevant procedures and regulations so as not to lose valuable time in an emergency until professional help arrives.

Approaching the victim

Motorized sports vehicles

After turning the stern away and disengaging the propeller, the ship must be brought back to the victim as quickly as possible. The ship is best controllable if the person who fell overboard is steered against wind and electricity. The maneuvers Single Turn , Williamson Turn or Scharnow Turn , which have also been tried and tested in commercial shipping, are suitable, as they always bring the ship back into its own wake.

Sports craft under sail

It is crucial that the maneuver can be performed safely, quickly and successfully. This also applies to maneuvers with a small (or less operational) crew, in an emergency even alone. The textbook maneuver, which is mostly taught in sailing schools ( space sheet course , Q-turn , half wind course , shoot-up ), is suitable for dinghies . The use of this maneuver on sailing yachts is dangerous because it takes up a lot of space, which means that the distance to the person who fell overboard is easily too great to keep an eye on when the sea is rough, and because when the sea is nearing, the pods are hit by the wind Rescuers and victims can be dangerously injured. In practice, the quick-stop maneuver and the Munich maneuver have proven particularly useful for keel yachts . Both form the “stable platform” necessary for the rescue, on which the ship lies still for several minutes and the sails do not flap.

Quick stop maneuvers
without changing anything on the sails, turn around and go once in a circle with thick sails (possibly with motor assistance) and turn . Enclosed record the victim to Lee . Quick stop can also be done with a small crew. The ship stays close to the victim.
Munich maneuvers
three ship lengths upwind , turn and drift back to the victim. The Munich maneuver can be driven with one hand.
Hamburger maneuver
Jib stops on the way back to the overboard stern. The sails are brought tight again in the turn, which leads to being enclosed in the final phase. The journey sinks to a minimum, the crew is not endangered by the pods striking the boat, the yacht heels heavily to leeward and thus facilitates the recovery.
Approach on the leeward side

The victim is approached so that it lies on the leeward side of the ship. The ship is stopped in such a way that the victim can be picked up amidships or in the rear third. During all maneuvers, a floating line with a lifebuoy is deployed, which the victim can hold onto if necessary and a line connection can be made if the ship does not hit exactly. By turning the ship in both maneuvers, it forms the stable platform required for recovery , with the tree already on the right side.

Establish line connection

It is crucial to immediately establish a line connection so that the victim can be held on the side of the ship, even if the ship drifts again.

Large shipping

If the person is sighted in the water, depending on the speed and position of the person in relation to the ship, maneuvering must be carried out in such a way that the ship is stopped at a short distance and in windward direction from the person driving. Standard maneuvers are the single turn , Williamson turn or Scharnow turn . The person should - as far as possible - be about amidships abeam in order to make sufficient leeward for the rescue . It is important to proceed in such a way that as few machine maneuvers as possible are carried out in the immediate vicinity of the injured person in order to avoid injuries from the screw.

The recovery

Rescuing a person who has fallen overboard is the most difficult phase in the course of the MOB maneuver. It is made even more difficult with an unconscious victim or a small crew. Often those who have fallen overboard die of drowning or hypothermia because they cannot be rescued.

The person is also weighed down by clothing soaked in water. For an average man, this quickly adds up to 100 kg. This weight is to be lifted out of the water on board; the deck of the boat or ship is barely one to several meters above that to be recovered. Rough seas, wind, panic, wet, slippery and swaying deck and dangerous sails and sheets flapping on sailing ships make the task even more difficult.

Rescues usually take time. A safe line connection to the victim is therefore important as early as possible when approaching the person overboard. Otherwise, especially when the sea is rough and there is a lot of wind, it is difficult to stay right next to the swimmer long enough without drifting away.

Recovery in windward or lee side

The question of whether a person should preferably be rescued on the windward or leeward side of the boat or ship is always controversial.

Dinghies

On dinghies, especially due to the higher risk of capsizing when resuming, the following applies: rescue in windward direction or at the stern of the dinghy.

Larger boats or ships

On larger boats or ships, the risk of capsizing is not relevant, instead, the following must be observed:

Salvage on the windward side
Pro: Less risk of the ship injuring or even killing the person to be rescued when stamping.
Pros on sailing yachts: If the ship is not correctly enclosed and the sails have not been recovered and the tree is not lashed down: Less risk to the rescuers from flapping sails and sheets and beating tree.
Cons: The wind pressure causes the ship to move away from the person to be rescued. No protection of the victim from wind and especially from rough seas. You cannot deploy a lifebuoy or line against the wind. The side wall is higher on this side. Rescuers find it difficult to work when facing the sea.
Salvage on the leeward side
Pro: The ship's side is lower on the leeward side, as the ship is inclined (heeling) due to wind pressure when it is enclosed. The ship drifts towards the victim and holds it on board for some time. On the leeward side the ship offers protection from the wind, and the sea ( swell ) is much calmer here. If necessary, a tree can be used as a “crane arm” to hoist the overboard person (see rescue with pulley ).
Cons: The ship can push itself over the person to be rescued and injure him.

practice

In practice, the following applies: The right side must be selected based on the situation. In lighter seas, the leeward side is often recommended. The decision depends on many parameters, in particular on the knowledge of the skipper and his skills and on his experience with the type of ship and his crew, as well as the skill and commitment of the crew. Sea state, wind strength, visibility, temperature play just as important a role as the equipment and condition of the ship, and the health and daily condition of the crew on deck. In the course of the maneuver, disruptive factors can undo the decision made in any phase. A failed maneuver, a wrong assessment of the approach, a blown sheet, a drifting ship, a missing line connection, an unstable too short rest position of the ship, inadequate aids and techniques for recovery and much more can require new solutions.

Rescue with pulley

Rescue by hand is usually impossible. The side wall is too high for that and the victim is much too heavy (see picture above). Rescue via the bathing platform is not possible even in moderate swell, as the ship stomps in the waves and the victim can be killed from the stern. In most cases, the victim can only with a pulley ( Talje be rescued).

Some vehicles have a pulley system on board especially for such recovery maneuvers, otherwise another pulley system with sufficient pulling force must be used. How and where the pulley system is best to be attached to the boat and guided depends on the respective ship and its equipment.

The lower end of the pulley system is either attached to the person who has gone overboard (or to a rescue loop, a lifebelt or similar that the person who has gone overboard carries). To slip something under the overboard, e.g. B. a net, a tarpaulin or a sail is practically impossible in rough seas. In calm water and an unconscious heavy person, a sail can be attached to one side of the boat on low boats (e.g. many sailing yachts), then a corner can be passed under the one to be rescued and pulled up on the other side using a pulley system. There are special recovery systems in large-scale shipping.

Attachment to the case

On smaller sailing yachts, the foredeck, directly in front of the shrouds , is often a good place to be brought on board, for example with the spinnaker halyard. The pulley is attached to it. The halyard can be stabilized forwards and backwards with two lines (spinnaker vang and the bow knocked off the headsail, or any auxiliary line). The point at which the three lines meet can thus be adjusted upwards, forwards and aft and fixed in order to set the optimal pulling point for the pulley. The pulley is then hoisted up, which allows the best possible use of force.

Direct hoisting with a halyard that goes over the masthead can lead to wedging if the line, which is pulled sideways under load, slips out of the pulley at the top of the masthead. This can then not be restarted from the deck. Due to the mast height, the angle to the fall is usually small enough to prevent this.

Attachment to the want

On larger yachts you will also find a permanently installed or mobile recovery pulley that can be attached to the shrouds.

Attachment to the tree as a crane arm

You can use the tree ( guided with sheet and bull stand ) as a "crane arm" to hoist up the overboard. It is beneficial that the boom dock (“end” of the boom) can then be fixed very easily and can also be swiveled over the deck. It should be noted that the boom is used for the mainsail as an attachment and for the recovery, and the recovery also influences the position of the sail and vice versa. The tree position is uncritical for the enclosure within larger limits and can also be deflected beyond this for a short time for recovery. Uncontrolled tree movement in heavy seas is problematic for rescuers and victims, whereby the stable position due to the wind pressure when lying around and the additional fixation by sheet and bull stand can largely prevent this. It is also unfavorable that the fixing point of the pulley block cannot be moved freely (e.g. not along the side of the ship). A tree prepared for recovery with a pulley system requires similar preparation time as recovery with a fall with a pulley system.

As an alternative to the pulley block at the end of the tree, a line can also be led through a prepared pulley at the end of the tree, which is then brought over a winch. The line guidance over the winch must have been practiced beforehand. Or you can simply put the line between the dirk and the sail over the end of the tree, making sure that the leech is not damaged. It is not possible to use the main sheet as a pulley block, because if this is unhooked on the traveler, the tree can no longer be steered to be enclosed.

Horizontal recovery from hypothermia

Horizontal recovery

In case of hypothermia , recovery should only be carried out horizontally . The blood in the limbs is strongly cooled and any movement of the victim would flush it into the vital organs and lead to rescue death. This also applies to a vertical rotation. Depending on the water temperature, hypothermia can occur in the water after just a few minutes. Hypothermia must always be recovered horizontally, if possible with a double overhang .

The rescue is often done by helicopter. The victim is saved horizontally in a basket. The rescuer is set down with a lifebelt and swimming helps the victim to get into the basket.

In large shipping

As a rule, which is to recover a person floating in the water rescue boat used. Depending on the nature of the ship and rescue boat, the sea area and the prevailing wind and sea conditions, however, this is not always possible. Under certain circumstances, it may be impossible to deploy the rescue boat without unreasonable endangerment to the boat crew, even at a swell of 3 to 4 meters. In such a case, an attempt must be made to rescue the person to be rescued using deployed pilot ladders, lines, net brooks or even life rafts , which are drifted leeward towards the injured person on their ripcords. A few ships also have a special recovery network in which the person to be recovered is hoisted up with a crane.

Chances of survival

Man overboard (1851) by Oswald Walters Brierly

Finding and recovering a person who has fallen overboard is difficult, especially at night or in rough seas. The likelihood of drowning can be significantly reduced by using a properly worn life jacket with a crotch strap that is safe to faint . Most people die from drowning (insufficient oxygen supply due to water and spray blocking the respiratory organs) or ventricular fibrillation as a reaction to stress and hypothermia.

The reactions of the body to the cold shock after immersion in water can lead to rapid drowning due to the cold shock and the uncontrolled breathing associated with it. In order to avoid death from drowning and hypothermia, it is important to perform the above maneuvers quickly and safely and to recover quickly.

With a functioning, properly worn life jacket, the possible survival time in the water depends primarily on the water temperature. Weather conditions, swell as well as the behavior, fitness and will to survive of the person overboard also play a role. Depending on the conditions, the survival time is between a few minutes and several hours. The person who has fallen into the water can, provided they are conscious, significantly increase their chances of survival by putting on a hood (because of the heat loss over the head), closing any fasteners on the sleeves and legs of the clothing and moving around as little as possible to reduce the exchange between the water heated by the body and the cold surrounding water. Active swimming should also be avoided.

Preventive measures on sports vehicles

Lifebelt and life jacket

To avoid falling overboard, a harness ( lifebelt ) and lifeline (lifeline) should be available on every boat . This equipment should be used in heavy weather or in the dark. A leash is attached to the safety belt with a snap hook, which can be hooked into the specially designed attachment points on the ship at any time. On many boats, the lifebelt can be attached to a safety line stretched from bow to stern so that you can move around safely and as freely as possible on deck. In addition, an unconscious life jacket must be worn in such conditions . Careful movement on the ship's deck and non-slip shoes also reduce the risk of falling overboard.

Alcohol on board and use of the toilet

Alcohol on board while driving increases the risk of overboarding and hypothermia . In addition, beer consumption promotes the urge to urinate and thus encourages a common cause of accidents: urinating overboard.

Briefing of the crew

Good seamanship requires that the crew be made aware of the risk of overboarding, preventive measures and necessary actions in an emergency. The man-over-board maneuver has to be practiced over and over again so that the decisive steps take place automatically in an emergency. Experience has shown that this is often neglected, especially on holiday trips. The skipper must ensure (in his own interest) that at least one other crew member can safely perform such a maneuver and that he masters all phases together with the rest of the crew.

MOB exercise

"Oskar overboard" is regularly trained in naval units.

To practice the man-over-board maneuver, a "buoy overboard maneuver" can be performed. This designation makes it unmistakably clear that this is not a real emergency, but nevertheless a serious exercise. Such a maneuver should be done at least at the beginning of a trip. Realistic conditions are required:

  • Swell that makes observation difficult
  • Wind that makes the maneuver difficult (from 6 Bft. )
  • Buoy with a 100 kg mountain weight

If such conditions do not exist, at least the individual phases should be practiced as realistically as possible. Rescue can, for example, be practiced in a bay in bathing weather. The "buoy" is then a crew member who turns unconscious.

literature

Web links

Commons : Man overboard maneuvers  - collection of pictures, videos and audio files

Individual evidence

  1. ↑ Product range
  2. ↑ a b For this paragraph cf. Manual for training in the ship safety service , See-Berufsgenossenschaft, o. Verl., Hamburg 1997
  3. ↑ On this paragraph cf. Handbook for Bridge and House of Cards , Federal Maritime and Hydrographic Agency, 2007 edition, ISBN 978-3-89871-156-2 .
  4. ↑ see e.g. B. Investigation report of the Federal Bureau of Maritime Casualty Investigation ( Memento of the original of September 28, 2007 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.bsu-bund.de