Fog is a natural phenomenon that creates high risks of collision of ships during shipping. The appearance of fog is due to the approach of the air temperature to the dew point by 3 degrees. Typically, fog extends over water or land. The peculiarity of swimming in fog is that when it appears, a decrease in the visibility range is inevitable (to values less than 1 km). According to the International Organization for Standardization (ISO), when the visibility is less than one mile, the phenomenon is called fog, if the visibility is greater, it is called haze.
There are two types of fog: sea and radiation. Marine, by definition, forms above the sea surface and is often carried by winds. Marine fog can extend over large sea or oceanic areas and tends to show up in regions where cool winds often blow. Radiation fog forms over the coast at night, when, after sunset, the surface of the earth and the air above it cool down to dew point temperature. Gradually, he slides from land to sea. As professional yachtsmen note 2yachts, the radiation type of fog is often accompanied by low-intensity air movements over the underlying surface and usually it dissipates towards the dining room. time. Any yachtsman should remember that if the fog is accompanied by wind, it means that it is of the sea type and by the middle of the day it will not dissipate like radiation.
In the fog, there is a sharp narrowing of the available methods of orientation and location. Imagine that on a quiet, sunny day on your weekend you are traveling along the coast and then suddenly everything changes - cold, thick and impenetrable fog envelops you from all sides, while visibility is reduced to several tens of meters and the coast is no longer visible. However, your successful return to the dock is called into question.
Regardless of the region of your sailing and which ship you are traveling on, the likelihood of falling under the influence of this atmospheric phenomenon remains higher than you might think. In many parts of North America, the Baltic Sea and the Sea of Japan, fog is common, so sometimes even a short sailing trip can have unexpected and unpleasant consequences if you do not have the proper experience and skills.
Preparing for unpredictable fog can noticeably soften the thrill of your first low visibility cruising experience. To make the movement to the destination or on the opposite course - to the port of departure, safe, both the basic traffic rules and some things that must be present on the ship can help.
The fog tests your knowledge and skills in the art of navigation. If the loss of visibility overtook your yacht on the way - you should try to calculate the position of the vessel before the coastline is lost from sight. You may change your original route and head for a harbor better equipped with aids to navigation, including floating signs equipped with audible signals. You can also turn back and head to the departure point that you know better than the upcoming harbors on the route. If you absolutely do not feel any confidence to continue moving, you should anchor and wait for the fog to clear.
Navigation with decreasing visibility envisages following the COLREGs-72, where one of the key rules states that in a situation of dangerous convergence of two vessels on opposite courses, each of them must change its course to the right, so that that each of the ships pass on the port side of the other.
In fog, however, you should act differently, since the ships are not located within the range of mutual visibility and can only be identified using radar or when they give sound alerts. The rules for sailing in poor visibility conditions are mandatory to use radar. Why is it necessary to have knowledge of the rules for using a radar device to detect the risk of collision and skills so that you can see on the monitor that the ship, for example, is overtaking your yacht or you are ahead of it, and whether there is a likelihood of a collision on cross-courses. The radar is by far the most important anti-collision instrument on board.
For simple navigation in reduced visibility conditions, you need a detailed map, nautical compass, beeper and VHF maritime radio. It has been experimentally determined that the audibility of sound warnings changes depending on the height of the observer above the water surface, as well as on the meteorological situation. When sound comes in from the windward side, it is better heard by the lookout, who is as high as possible above the deck, and, on the contrary, when it comes in from the leeward side, it is better heard by the one on the deck. Therefore, when conducting auditory observation, it is best to place observers on the tank and on the upper bridge. Raising the radar reflector and securing it higher is also a good solution.
If it is decided not to stop and move in the same direction, you should slow down and, if possible, put one of the team members on the bow of the yacht as a lookout. For yachts with a length of 12 m and more, the traffic rules provide for the use of special sound signals, regardless of whether the vessel is moving or anchored.
While driving, you should carefully listen to signals coming from other yachts and ships, as well as signals emitted by floating signs and beacons. It should be borne in mind that not all participants in traffic on waterways can give correct signals, and you need to be prepared to hear the sounds of a vessel approaching you. When you find the correct signal within your course, slow down and continue moving more carefully until you realize that you have cleared the oncoming object. Reducing the speed is extremely important as it becomes more difficult to determine the direction of the audio signals in conditions of reduced visibility.
In areas with heavy commercial vessel traffic, it is important to constantly listen to VHF radio, tracking information about the location and movement of vessels. For even greater safety, may be transmitting information about your yacht's position, speed and course on channel 16 VHF or on another fixed frequency for broadcasting trade routes in the area.
If you live in one of the regions with frequent fog, or your route is laid through similar areas, you should take care of purchasing additional electronic devices for more stable determination of your own position and location of ships in your environment. Thanks to the GPS system, it will not be difficult for the yachtsman to determine his position at any time. With the help of a pocket navigator, you can record routes on a digital map and thus easily bypass any risky moments in your journey. But do not forget that the GPS navigator will not help you in the event of a risk of collision with other road users.
As already mentioned, for these purposes the most suitable device is a radar that can replace your eyes for a while when you get into a fog zone. With the help of the radar, the coastline, buoys and other vessels on the route will immediately be visible on the screen of the device, and the integrated application of the GPS radar will give you visual information about the location of the next point on the planned route.
Special software designed to work with digital maps will be able to guarantee you the receipt of such an amount of information, which will be enough in excess to determine the yacht's position as accurately as possible. Having a complex of electronic devices on board in a foggy environment is like using additional layers of information that complement each other. You can feel much more confident in poor visibility if, having recorded the sound of a signal from one of the buoys, you can immediately identify it on the map, see it on the radar monitor and observe the yacht's position in relation to this floating mark on the map.
If you are interested in yacht rental in one of your chosen regions - we advise you to contact the professionals of the 2yachts company, with their help you will not only you will choose a yacht of your dreams, but also solve all the accompanying tasks (expert determination of the technical condition, insurance, registration of the vessel, etc.).