1.Williamson turn
Advantage -
makes good original track line
good in reduced visibility
simple
Disadvantage -
takes the ship farther away from the scene of the incident
slow procedure
Execution of Williamson turn -
Rudder hard over (in an "immediate action" situation, only to the side of the casualty).
After deviation from the original course by 60°, the rudder hard over to the opposite side.
When heading 20° short of the opposite course, the rudder to the midship position and ship will be turned to the opposite course.
2.One turn ("Single turn, Anderson turn")
Advantage-
fastest recovery method
good for ships with tight turning characteristics
used most by ships with considerable power
Disadvantage-
very difficult for a single-screw vessel
difficult because the approach to a person is not straight
Execution of Anderson turn-
Rudder hard over (in an "immediate action" situation, only to the side of the casualty).
After deviation from the original course by 250°, rudder to midship position
and stopping manoeuvre to be initiated.
3.Scharnov turn
Advantages-
will take the vessel back into her wake
less distance is covered, saving time
Disadvantages-
cannot be carried out effectively unless the time elapsed between the occurrence of the incident and the commencement of the manoeuvre is known
Execution of Scharnov turn-
(Not to be used in an "immediate action" situation.)
Rudder hard over.
After deviation from the original course by 240°, rudder hard over to the opposite side.
When heading 20° short of opposite course, rudder to midship position so that ship will turn to the opposite course.