Question 1

You are on lookout at night and sight a vessel showing a masthead light, sidelights and a sternlight, all visible to you. Roughly what does this tell you about her aspect relative to your vessel?

Accepted Answer

It is unusual to see all of these at once — most likely you are seeing her broadly from one side, where the relevant sidelight (10 points / 112.5° arc) and the masthead light (225° arc) overlap, while the sternlight (135° arc) covers the remaining arc astern of her Annex I defines the arcs of visibility: sidelights show over an arc of 112.5° from dead ahead to abeam and slightly aft on their respective side, masthead lights show over 225° (dead ahead to slightly aft of the beam on each side), and the sternlight covers the remaining 135° arc astern. From most viewing angles you would only see one sidelight plus the masthead light, or the sternlight alone — seeing a combination usually means you are observing from somewhere near the boundary of two arcs, broadly abeam.

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.