Question 1

An air-cushion vessel (e.g. a hovercraft) is operating in the non-displacement mode. What additional identification does Rule 23(b) require beyond standard power-driven vessel lights?

Accepted Answer

An all-round flashing yellow light, in addition to the lights prescribed for power-driven vessels — alerting other traffic to her unusual mode of operation and potentially different manoeuvring characteristics Rule 23(b) requires an all-round flashing yellow light for air-cushion vessels in non-displacement mode — a useful identifier for other vessels given the very different speed and manoeuvring profile of such craft compared to conventional vessels.

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.