AIS
The Automatic Identification System (AIS) is a shipborne navigation safety system that automatically transmits and receives vessel information such as identity, position, course, speed, and navigational status. As required by SOLAS Chapter V, Regulation 19 and IMO performance standards, AIS enhances situational awareness, collision avoidance, and vessel traffic management.
Is AIS mandatory under SOLAS?
Yes. SOLAS Chapter V, Regulation 19 mandates AIS for:
All ships ≥300 GT on international voyages
Cargo ships ≥500 GT not on international voyages
All passenger ships
What is the main purpose of AIS?
AIS improves collision avoidance, supports VTS operations, and enhances maritime safety and security.
What information does AIS transmit?
AIS transmits:
Vessel name & MMSI
Position (GPS)
Course & speed
Navigational status
Voyage-related data
Does AIS replace radar or lookout?
No. IMO clearly states AIS is a supporting tool and does not replace radar, lookout, or COLREG obligations.
Should AIS always be switched on?
Yes. AIS should be operational at all times, except where security concerns justify temporary switch-off, as per IMO guidelines.
What are the types of AIS?
Class A AIS – SOLAS-compliant, mandatory for ships
Class B AIS – Non-SOLAS vessels, limited functionality
Is AIS required to be connected to other systems?
Yes. AIS must interface with GPS, gyro compass, speed log, ECDIS, and radar where applicable.
How is AIS checked during PSC or Class inspections?
Surveyors verify:
Continuous transmission
Correct static and voyage data
Alarm functionality
Proper integration with bridge systems
Can AIS data be used as legal evidence?
AIS data may support investigations, but it is not the sole source of evidence and must be verified with other records.
What happens if AIS fails?
The failure must be recorded in the logbook, and repairs should be arranged at the earliest opportunity, as per flag and class requirements.
Conclusion
AIS is a SOLAS-mandated navigation safety system that significantly enhances vessel awareness and traffic monitoring. When properly maintained, correctly configured, and continuously operated in line with IMO guidelines, AIS plays a crucial role in preventing collisions and ensuring safe navigation at sea.