Question 1

You're told to watch for a vessel displaying two black balls in a vertical line during daylight hours. In plain terms, what does this shape mean and why does it matter that you report it straight away?

Accepted Answer

It means the vessel is Not Under Command — she has lost the ability to manoeuvre as normal, so unlike an ordinary vessel she may not be able to keep clear even if she wants to. That makes an early report critical, since your own vessel may need to take avoiding action rather than assume the usual give-way/stand-on rules will sort it out Two black balls in a vertical line (Rule 27(a)) signals a vessel Not Under Command — one of the most important shapes to recognise immediately, because it flips the normal assumption that another vessel will manoeuvre to avoid you. A rating who spots this and reports it promptly gives the OOW the time needed to plan around a vessel that genuinely cannot help herself.

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.