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MOB ACTIONS?
MOB ACTIONS?
Please this read this page carefully before attempting the quiz at the bottom
Instant Action MOB noticed from the bridge and instant action taken | Delayed action MOB reported to bridge by witness and action taken with some delay | Person Missing action Person reported to the bridge as missing |
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Hard Over to the side of MOB Release MOB marker Sound Three Prolonged Blasts On The Ships Whistle Put mark on GPS & ECDIS Display RAM (as nature of work SAR) Commence Recovery Manoeuvre. Single / Anderson turn Raise Alarm, Inform Master Note Position, Wind Speed And Direction And Time. Post lookouts To Keep The Person In Sight. Send distress message out Prepare Rescue Boat Rig Scrambling nets | Raise alarm, Inform master Display RAM (as nature of work SAR) Commence Recovery Manoeuvre. Williamson Turn Note Position, Wind Speed And Direction And Time. Post lookouts To Keep The Person In Sight. Send distress message out Prepare Rescue Boat Rig Scrambling nets | Make announcement for the person and re-check for him If still not found Raise alarm, Inform master Find the time elapsed since the occurrence of the casualty Display RAM (as nature of work SAR) Commence Recovery Manoeuvre. Scharnow Turn Note Position, Wind Speed And Direction And Time. Post lookouts To Keep The Person In Sight. Send distress message out Prepare Rescue Boat Rig Scrambling nets |
Anderson/Single turn – For Immediate Action
The Anderson turn is most appropriate when the point to be reached remains clearly visible because it’s quickest of the 3 manoeuvres.
It is good for ships with tight turning characteristics with considerable power but very difficult for single screw vessels.
It is also very difficult manoeuvre because approach to person is not straight.
1. Rudder Hard Over to the Side of the Casualty.
2. After Deviation from the Course by 2500 Rudder to Midship Position.
3. Stopping Manoeuvre To Be Initiated.
Always bring the vessel upwind of the person. Stop the vessel in the water with the person well forward of the propellers.
Williamson turn – For Delayed Action
The Williamson turn is most appropriate at night or in reduced visibility, or if the point can be allowed to go (or already has gone) out of sight, but is still relatively near.
WILLIAMSON TURN will take the ship to the scene of the casualty most surely. SCHARNOW TURN cannot be carried out effectively unless the time elapsed between the occurrence of the casualty and the commencement of the manoeuvre is known therefore Williamson turn is best in delayed action situation.
1. Put the rudder hard over.
2. After deviating from the original course by about 60 degrees, shift the rudder full to the opposite side.
3. When heading about 20 degrees short of the reciprocal, put the rudder amidships so that vessel will turn onto the reciprocal course.
Always bring the vessel upwind of the person. Stop the vessel in the water with the person well forward of the propellers.
Scharnow turn –For Person missing action
The Scharnow turn is most appropriate when the point to be reached is significantly further astern than the vessel's turning radius.
Both WILLIAMSON TURN and SCHARNOW TURN will take the ship back into her wake but since less distance is covered, and thus time is saved, when carrying out SCHARNOW TURN it is preferred in missing person situation.
1. Put the rudder over hard over.
2. After deviating from the original course by about 240 degrees, shift the rudder hard to the opposite side.
3. When heading about 20 degrees short of the reciprocal course, put the rudder amidships so that vessel will turn onto the reciprocal course.
Always bring the vessel upwind of the person. Stop the vessel in the water with the person well forward of the propellers
Now try the Quiz
The sequence of questions and answer randomise so you can try them several times.