Under Rule 5, which equipment should be used in addition to a visual lookout to identify potential collision threats?

• A. AIS and radar.
• B. VHF radio only.
• C. Echo sounder.
• D. GPS only.

Answer: (A)

Rule 5 asks you to maintain a proper lookout by sight and hearing and to use all available means to identify potential collision threats. When you’re equipped, that includes AIS and radar alongside your visual watch. AIS provides data about nearby vessels—who they are, where they’re headed, how fast, and their course—so you can assess collision risk even before you sight them. Radar fills in with real-time relative positions, ranges, and bearings of targets, letting you track their motion and judge whether a risk of collision exists. The other options don’t offer the same threat-identification capability: a VHF radio is for communication, not detecting other vessels; an echo sounder measures depth, not traffic; and GPS alone gives your own position, not information about other vessels.