A collision has occurred between your vessel and another. The other vessel had been tracked on ARPA for 18 minutes. CPA was computed at 0.15nm from first acquisition. No COLREGs action was taken until 2 minutes before collision when both vessels altered to port simultaneously. What were the failures?

A. Identified failures against COLREGs and seamanship standards: (1) Rule 7 — Risk of collision: CPA 0.15nm from first acquisition = risk of collision from the start; this was not recognised or acted upon promptly; (2) Rule 8 — Action in ample time: 18 minutes of tracking with no action = clear failure; action should have been taken when CPA first showed an unsafe value (16+ minutes before collision); (3) Rule 8(b) — Action readily apparent: altering to port 2 minutes before collision is neither early nor large enough to be effective; (4) Rule 8(d)/19(d) — Both altering to port simultaneously: if the contact was forward of the beam, altering to port is specifically prohibited under Rule 19(d) (if in restricted visibility) and is seamanship-poor in clear weather (converging alteration); (5) Rule 17 — stand-on obligations not honoured if one vessel was stand-on and altered to port in the wrong direction; (6) Root cause — ARPA watch-keeping failure, automation complacency, failure to apply the "steady bearing decreasing range" risk assessment.

B. The collision was caused by the other vessel failing to give way. Your vessel was stand-on and maintained course and speed — this is correct COLREGs compliance.

C. The failure was taking action too late at 2 minutes — earlier action of the same type (port alteration) would have been effective.

D. Both vessels failed equally — in a collision at sea both vessels are always 50/50 at fault regardless of COLREGs compliance.

A. Management-level framework for a close-quarters situation: (1) Brief the master concisely on arrival: target bearing, CPA, TCPA, action already taken (course/speed changes), what response (if any) from the other vessel; (2) Confirm your own vessel's status: current course, speed, engine readiness; (3) Apply Rule 17(b) — if the give-way vessel has not acted and a collision cannot be avoided by the give-way vessel alone, the stand-on vessel (if that is you) SHALL take action. This is now a mandatory action, not a permissive one; (4) Rule 2(a) — General Prudential Rule: "Nothing in these Rules shall exonerate any vessel... from the consequences of any neglect to take all precautions which may be required by the ordinary practice of seamen"; (5) Take action EARLY and LARGE — a late small alteration is less effective and less visible than an early substantial alteration; (6) Document actions in the deck log with times; (7) Post-incident: write an OOW narrative of events for the file.

B. Once the master is on the bridge, all COLREGs responsibility transfers to the master. Inform him of the situation and step back — the Chief Mate has no further COLREGs obligation.

C. At management level, VHF contact with the other vessel must be established before any manoeuvre. Contact MRCC for assistance identifying the non-responding vessel.

D. Rule 17 does not apply at sea — it is only relevant in port approaches and narrow channels. In open water, both vessels are equal stand-on until one acts.

A. TSS-specific passage planning obligations (Rule 10 and SOLAS V/34): (1) Identify all TSS on the route — plot them on charts, note their direction of traffic flow and separation zones; (2) Plan the route to navigate in the correct lane (Rule 10(a) — join and navigate in appropriate lanes); (3) If crossing is necessary, plan to cross at right angles to the lane direction (Rule 10(c)); (4) Plan to avoid anchoring in or near a TSS unless in an emergency (Rule 10(g)); (5) Note any deep-water routes or inshore traffic zones relevant to the vessel's draught; (6) Research MSI broadcasts for TSS — check for restricted areas, military exercises, or temporary changes to the scheme; (7) Brief the master in the pre-departure voyage plan review — specifically note any TSS crossing points and their timing (daylight/night preference, tidal considerations); (8) Identify VHF traffic advisory services (CNIS Dover Strait, Jobourg Traffic, Gris Nez Traffic) associated with each TSS.

B. TSS planning only requires noting the lane direction on the chart. The OOW on watch at the time handles all TSS decisions in real time.

C. Traffic Separation Schemes are voluntary under SOLAS for vessels over 300 GT. Planning teams should note but not restrict passage plan options based on TSS.

D. Rule 10 only applies to vessels that are lane-traffic. A vessel transiting through a TSS at an angle is not subject to Rule 10 and can navigate freely.