IRPCS Flashcards

What lights does a vessel 'not under command' display at night?

Answer: Two all-round red lights in a vertical line, plus sidelights and stern light if making way

A vessel not under command (NUC) displays two all-round red lights in a vertical line. If making way through the water, she must also display sidelights and a stern light, but no masthead light.

Under Rule 10, what obligations does a vessel have when navigating in a Traffic Separation Scheme (TSS)?

Answer: She must use the appropriate traffic lane in the general direction of traffic flow, join and leave at a shallow angle, and avoid crossing if possible

In a TSS, vessels must travel in the correct lane, join/leave at as shallow an angle as practicable, avoid crossing but if necessary cross at right angles. Vessels under 20m or sailing vessels must not impede vessels following the lane.

What does a single prolonged blast followed by two short blasts signify?

Answer: A vessel in restricted visibility that is not under command, restricted in ability to manoeuvre, constrained by draught, sailing, fishing, or towing

One prolonged followed by two short blasts is the fog signal for vessels that are: NUC, RAM, CBD, sailing, fishing, or engaged in towing/pushing. It identifies vessels with restricted manoeuvrability in poor visibility.

According to Rule 8, what are the requirements for action to avoid collision?

Answer: Action must be positive, made in ample time, large enough to be readily apparent to the other vessel, and made with due regard to good seamanship

Rule 8 requires that avoiding action be: taken in ample time, positive and obvious (large enough to be detected by radar), and made with good seamanship. Small, tentative alterations should be avoided.

What is a 'vessel constrained by her draught' (CBD) and what lights does she display?

Answer: A power-driven vessel deeply loaded and severely restricted in ability to deviate from the course being followed — displays three all-round red lights in a vertical line in addition to normal lights

A CBD vessel is a power-driven vessel so deeply loaded that its draught severely restricts its ability to deviate from its course. It displays three all-round red lights in a vertical line plus its normal power-driven vessel lights.

Under Rule 6 'Safe Speed', what factors must be taken into account when determining safe speed?

Answer: Visibility, traffic density, manoeuvrability of the vessel, background lights, sea state, wind, current, navigational hazards, and the vessel's draught in relation to available depth

Rule 6 lists extensive factors for determining safe speed: visibility, traffic density, manoeuvrability, night conditions (background lights), sea and wind state, navigational hazards, and draught relative to depth. Radar performance is also relevant.