Following the disaster of the Bayesian yacht which sank off the coast of Little Port (Palermo) on August 19th and which caused 7 victims, there is a lot of talk about the AIS system (Automatic Identification System). This is a system of tracking which allows vessels to share a range of information with each other, such as their own real time locationThe main objective of the AIS is to Avoid collisionsbut – in this case – it could also help the power of attorney to reconstruct the movements of the Bayesian and shed light on the sequence of events which led to its sinking.
How the AIS system works
The AIS system, as anticipated, has the task of tracking all the vessels in a certain area and, to do so, it sends and receives via VHF radio signals (Very High Frequency) two types of data: static And dynamic. I static data They are entered by the operators of each vessel and concern the characteristics of the vessel such as the name, model, width, length, tonnage, etc.
THE dynamic data instead they concern the position of the ship in real time, the destination and the route. To obtain this data, the GPS or a sensor internal to the AIS itself.
All this information is broadcast at regular intervals to other vessels and to the coast, receiving in turn signals of this kind. As confirmed by NATO, the reception distance of the signal can fluctuate from a minimum of 20 nautical miles (equivalent to approximately 37 km) to a maximum of 350 (about 650 km), even if the average value is around 40 nautical miles (approximately 74 km). This distance depends on various factors, such as atmospheric and sea conditions, the height of the receiving and transmitting antennas, and the power of the vessel’s transmitter.
What is the AIS system for?
As anticipated, the main function of this system is to increase safety and limit possible collisions between vessels. In reality, however, there are also advantages in using this tool, such as the possibility of analyze your movementsso as to optimize speed and trajectory and consequently reduce consumption. It is also possible to see the situation of the maritime traffic in a certain area, so as to have a clearer idea of the situation and understand which route is best to take.
The last advantage is the possibility – as in the case of the Bayesian – to reconstruct the ship’s movements in the minutes preceding the disaster, so as to help the authorities better understand the dynamics of the shipwreck.
Is the AIS system mandatory?
THE’IMO (International Maritime Organization), through the Convention for the Safety of Life at Seaestablishes that all vessels with tonnage equal to or greater than 300 GT employed in international travel and all passenger ships – regardless of size – must be equipped with an AIS system. Furthermore, this system, with rare exceptions, must always be activeboth when the ships are sailing and while they are at anchor: this is because turning it off could help criminals in carrying out illegal activities in complete secrecy.
Attention: It is good to keep in mind that this system It is not a replacement for radarbut rather a useful ally to be used in parallel to ensure greater safety.
