In fog, two radar contacts are tracked: Contact A — bearing 350°, range 2nm, CPA 0.3nm in 6 minutes; Contact B — bearing 090°, range 4nm, CPA 0.8nm in 15 minutes. How do you manage both?

A. DUAL RADAR CONTACT MANAGEMENT — MASTER'S ASSESSMENT: CONTACT A (350°, 2nm, CPA 0.3nm/6min): (1) PRIORITY — HIGHEST: CPA 0.3nm in 6 minutes is a developing close-quarters situation. 6 minutes is NOT ample time — it is marginal; (2) ACTION REQUIRED NOW: Rule 19(d) — take action to avoid collision. Contact A is forward of the beam (350° — nearly dead ahead). Rule 19(d)(i) restriction: do NOT alter course to port; (3) AVOIDING ACTION: starboard alteration (20-30°) or speed reduction, or both. Effect must be monitored to confirm CPA opens; CONTACT B (090°, 4nm, CPA 0.8nm/15min): (1) ASSESSMENT: 0.8nm CPA and 15 minutes — less immediate. CPA 0.8nm in open ocean may be acceptable; in restricted visibility in a busy area — potentially still a concern; (2) MONITOR: maintain track and watch for CPA change. No immediate action needed but monitor closely; INTERACTION PROBLEM: any avoiding action for A must be assessed for its effect on the CPA with B. (a) Alteration to starboard for A — will this improve or worsen B? Contact B is on the starboard beam. Turning starboard will bring you toward B — check the new CPA; (b) Speed reduction for A — what is the effect on B? Reducing speed may allow A to pass ahead and may improve the situation with B; (3) MASTER'S DECISION: reduce speed significantly (reduces closing rates with both); starboard alteration for A — assess new CPA with B; monitor both constantly; call for additional ARPA assistance from OOW.

B. Contact A is the only priority. Alter hard to port to maximise distance from Contact A — Contact B is too far away to be a concern.

C. Call both vessels on VHF Ch 16 and agree passing arrangements before taking any helm action. VHF coordination is more reliable than independent manoeuvres.

D. Stop engines immediately for both contacts — stopping is always the correct action when multiple close-quarters situations develop in fog.

A. COMMAND DECISION — 100M VISIBILITY: 100m visibility is extreme — visibility less than the vessel's own length. THE CORRECT DECISION: this vessel should NOT proceed into the Dover Strait TSS in 100m visibility. REASONING: (1) RULE 6 SAFE SPEED: a 200m tanker in ballast at any speed above absolute minimum cannot stop within 100m. Even at 3 knots, the stopping distance far exceeds visibility. No manoeuvrable speed satisfies the Rule 6 safe speed test; (2) TSS TRAFFIC: Dover Strait carries ~500 vessel transits per day. Other vessels of all sizes are in the TSS. At 100m visibility, you have zero warning of oncoming traffic until they are within 100m — effectively no warning; (3) MASTER'S AUTHORITY: under SOLAS V/34-1, the master's authority to make decisions for safety of the vessel is absolute. Commercial considerations CANNOT override this; (4) LEGAL EXPOSURE: proceeding in 100m visibility with no ability to comply with Rule 19 (safe speed, effective avoiding action) and causing a collision will result in criminal prosecution, civil liability, and potential imprisonment for the master; (5) CORRECT ACTION: wait. Heave-to outside the TSS or anchor in the Downs anchorage. Advise owners and charterers. The delay is finite — UK fog events typically last hours, not days; (6) ISM CODE: the ISM Code Section 5 gives the master overriding authority on safety matters. The company CANNOT instruct the master to proceed unsafely. Any such instruction must be refused and documented.

B. Proceed at 3 knots — this is safe speed in 100m visibility. ARPA will detect vessels in time at this slow speed and you can take avoiding action.

C. Increase speed to transit the Dover Strait as quickly as possible. Less time in restricted visibility equals less total risk.

D. Contact Dover VTS and ask them to clear the traffic lane before you transit. VTS has authority to hold other traffic while you pass.

A. FOG COLLISION LEGAL CONSEQUENCES — MASTER: (1) IMMEDIATE: render assistance to survivors (SOLAS V/33 — duty to assist); call MRCC for SAR; sound MAYDAY; recover survivors; (2) PRESERVE EVIDENCE: do not erase VDR. Preserve deck logs, ARPA recordings, bridge audio, AIS data, weather records, watch logs. Contact company DPA and P&I Club immediately; (3) COASTAL STATE: UK coastguard will direct the tanker to port for inspection. Do NOT depart the area without coastguard permission; (4) MCA INVESTIGATION: Marine Casualty Investigation under the Merchant Shipping (Marine Accident Investigation) Regulations 2012. MCA inspector will attend and seize records; (5) MAIB: the Marine Accident Investigation Branch (MAIB) will conduct an independent investigation under the Merchant Shipping (Accident Reporting and Investigation) Regulations 2012. MAIB is NOT a prosecutorial body but its reports are used as evidence; (6) CRIMINAL LIABILITY — MASTER: if the collision was caused by grossly negligent navigation (excessive speed in fog is classic), the master faces: (a) Gross negligence manslaughter (common law) — up to life imprisonment; (b) Health and Safety at Work Act offences; (c) COLREG violations (Merchant Shipping Act 1995 S98); (7) CIVIL LIABILITY: shipowner's P&I Club handles the civil claim from the fishing vessel owner and the deceased's family; (8) CoC SUSPENSION: MCA may suspend the master's certificate pending investigation; (9) FORMAL INQUIRY: if the circumstances warrant, a Formal Investigation (akin to a public inquiry) may be ordered under the Merchant Shipping Act 1995.

B. The company's P&I insurance covers all consequences. The master only needs to file an incident report with the company and no further personal legal exposure exists.

C. Collisions at sea are governed exclusively by COLREG — the master will be assessed under COLREG Rule 19 and no criminal proceedings can arise from a maritime collision.

D. Contact the company's lawyers before making any statements. The master should not communicate with the coastguard, MAIB, or MCA until legal representation is in place.