No, AIS does not prevent ship collisions by itself. It serves as a supplementary tool for identification and situational awareness that supports bridge judgement but never replaces visual lookout, radar plotting, or compliance with the COLREG.
AIS is intended to help identify and track ships, support search and rescue and information exchange, and improve situational awareness as a supplement to radar and other navigation information. However, AIS target position and motion are supplied by the target's equipment, whereas radar provides own-ship measurements; the two may therefore disagree and should be cross-checked.
Because AIS does not prevent collisions by itself, it cannot replace visual lookout, radar plotting, use of all available means or compliance with the COLREG. Mariners must rely on their own judgment and established collision regulations rather than assuming the system provides automatic safety for every vessel at sea.
