Question 1

You're keeping watch in fog and your AIS shows a target's speed-over-ground as very low. Based on MAIB's findings on the ANL Wyong/King Arthur collision, what should you do before deciding the vessel is stopped and no avoiding action is needed?

Accepted Answer

Cross-check the AIS-derived assessment against radar before concluding the target is not a collision risk King Arthur's OOW misread ANL Wyong's AIS data as showing the vessel stopped, when she was in fact making way, and took no avoiding action as a result. MAIB's Rec 2020/115 exists specifically because AIS must be cross-checked against radar, not relied on alone, in restricted visibility.

Question 2

Rule 5 (Look-out) requires every vessel at all times to maintain a proper look-out by sight and hearing, as well as by all available means appropriate in the prevailing circumstances and conditions — and this duty applies even when the vessel is at anchor in a busy anchorage.

Accepted Answer

True True. Rule 5 applies 'at all times' and to 'every vessel'. A vessel at anchor in a busy anchorage still needs an effective look-out to detect drifting vessels, dragging anchors, or approaching traffic that may pose a risk of collision or contact.

Question 3

Under Rule 6 (Safe Speed), a vessel fitted with a fully operational radar and ARPA never needs to reduce speed in restricted visibility, because the equipment guarantees early detection of other vessels.

Accepted Answer

False False. Rule 6 explicitly lists radar capability as one factor to consider, but also requires accounting for the state of visibility, traffic density, manoeuvrability, and the limitations of radar (range scale, sea/rain clutter, blind sectors). Even a vessel with excellent radar must proceed at a speed that allows proper and effective action to avoid collision and to be stopped within a distance appropriate to the prevailing circumstances.