The twin pillars on which every VTS decision rests
AIS builds the picture, communications make it actionable.
No traffic management service can function without two inseparable elements: a continuous, reliable stream of vessel identification and position data, and a two-way communication channel between the VTS Centre and every vessel in its area.
Together they turn passive observation into active traffic management, the essential precondition for the three VTS functions defined by IMO A.1158(32)
Data and dialogue
What each pillar contributes to the operational picture
AIS message types used by VTS
VHF channel assignments
International distress, safety and calling channel - mandatory watch
UK small craft safety channel (Coastguard)
Port operations - secondary VTS working channel
Port operations assigned by port authority
Where the two pillars meet
From separate feeds to a single, trustworthy picture