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All questions
Radar versus AIS

What should you do with a radar echo that has no AIS label?

Short answer

Treat it as a real possible target until identified or safely passed

Many real targets do not transmit AIS, may not be received or may be filtered from presentation. Keep the radar evidence until identified or safely passed. Revisit Association, Filters, and Target Identity.

Quick check

What should you do with a radar echo that has no AIS label?