Role and Types of Aids to Navigation

For the safe and efficient navigation of vessels,it is important that the vessels recognize their accurate position and maintain the fixed course.
Aids to navigation are established to assist vessels in the wide ocean where land marks are not visible,areas crowded with vessels,narrow channels,and areas with dangerous obstacles.
Vessels ascertain their positions by lights,shape of objects, colors,sound and radio waves.
There are many types of aids to navigation which may be classified as follows.


Aids to Navigation Visual Aids Lighthouses,Off Shore Fixed Lights,Light Staffs,Lighted Buoys,Projectors,Leading Lights,Sector Lights
Radio Aids Loran C,Differential GPS,Radio Beacon(MF,Micro Wave)
Audible Aids Fog Signals
Others Vessel Traffic Signal Stations,Tidal Stream Signals