Night crossing with a steady-bearing ferry, an unresponsive give-way vessel and closing fog
MV Ardent is a 190 m ro-ro ferry making 16.0 knots on 000°T. It is 0230 in moderate rain with visibility about 2 NM. The radar shows a freight ferry bearing 020° on the starboard bow at 5.0 NM, closing at 0.6 NM per minute, with a steady bearing and an ARPA CPA of 0.1 NM. Neither vessel has made a sound signal. Ahead and slightly to port at 3 NM there are two red lights in a vertical line. A third vessel showing red over white is crossing from port at about 8 knots and will pass well ahead. Traffic density is increasing and Ardent is 8 NM from the boundary of a traffic separation scheme. The master is below and the second officer is the officer of the watch.
1. Classify the situation with the ferry on the starboard bow and state the action required, including signals and timing.
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The ferry bears 020° on the starboard bow in a crossing situation, so Rule 15 applies and Ardent is the give-way vessel because the other vessel is on her starboard side. Rule 16 requires early and substantial action to keep well clear; a token 5° alteration at 5 NM with 0.6 NM/min closure is not substantial and would leave the other ship in doubt.
At about 4 NM, alter course 40–50° to starboard, enough to pass astern of her and open the CPA to at least 1–2 NM, and sound one short blast (Rule 34(a)) as the alteration is made. Avoid crossing ahead; avoid a succession of small alterations. Reduce speed if the alteration alone does not open the CPA. Hold the new course and watch the bearing: a bearing that opens steadily confirms the action has worked, and the ARPA should be re-set to check the new CPA and TCPA.
The vessel showing red over white is engaged in fishing other than trawling. Under Rule 18(a) a power-driven vessel keeps out of her way, but at 3 NM and crossing from port with a clear passing distance she does not compete with the ferry for immediate action. The two red lights ahead are a vessel not under command, which everyone must avoid if possible; note her and keep clear, but she is not the burdened vessel in the crossing.
2. At 1.2 NM the ferry still holds course and speed and does not answer the whistle. What does Rule 17 permit and require, and what manoeuvre do you choose?
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Ardent is the stand-on vessel, but Rule 17 does not require her to hold course into a collision. Under 17(b) she may act as soon as it is apparent the give-way vessel is not taking appropriate action; under 17(c), when collision cannot be avoided by the give-way vessel alone, she must take the best action to aid avoidance; under 17(d) the duty to avoid collision overrides the stand-on obligation.
At 1.2 NM and closing at 0.6 NM/min there is no time for a series of small changes. Choose one bold action that is unmistakable: a large alteration to starboard, combined with a reduction in speed or stopping the engines, is usually the most reliable way to open the passing distance and to reduce the closing energy. Sound at least five short and rapid blasts (Rule 34(d)) to show doubt or danger; if the other vessel is very close, the whistle and the manoeuvre are made together. Do not alter to port: the ferry is on the starboard side, and turning to port would turn toward her track and violate Rule 17(c)'s caution against altering to port for a vessel on your own port side. Keep the engines ready for full astern, brief the bridge team, and call the master.
3. Fog closes in and visibility falls to 300 m. The ferry is now a radar-only contact. What changes in your obligations and what do you do?
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In restricted visibility Rule 19 replaces the crossing rules: there is no stand-on or give-way vessel, and every vessel must proceed at a safe speed for the conditions, with engines ready for immediate manoeuvre, and must have regard to radar, visibility and traffic density.
Actions: reduce speed to the point where the ship can be stopped within half the visible range, which at 300 m visibility is very slow; increase the radar watch and plotting; switch to the fog signal for a power-driven vessel making way, one prolonged blast at intervals of not more than two minutes (two prolonged blasts with a gap when stopped and not making way); post extra lookouts forward, close the watertight doors, and sound the bell or gong if stopped.
When a contact is detected by radar alone, decide early whether a close-quarters situation is developing. If so, take avoiding action in ample time; alter to starboard for a contact forward of the beam rather than to port, and avoid altering toward a vessel abeam or abaft the beam. With visibility down to 300 m and traffic building, the safest decision is to hold off outside the lane boundary, or to continue only at a speed that allows a stop, and to inform the master. Entering or continuing in a traffic lane when you cannot see far enough to keep clear is a judgement against you.