Constrained by Draft: A Narrow-Channel Crossing at Night
At 21:40 in good visibility, the 12,000-gross-ton chemical tanker MV Sajo Pioneer, drawing 11.4 m, is outbound at 14 knots in a 0.6-nautical-mile-wide dredged channel. She displays three all-round red lights and keeps to the starboard edge. Radar and AIS show the 14-metre trawler Haemaru, showing red over white, crossing from the tanker's starboard bow at 3.5 knots, heading west; CPA 0.15 nautical miles in 5 minutes. The tanker's OOW calls on VHF 16: 'Haemaru, I am the give-way vessel, I will pass ahead of you.' The reply is unintelligible. The master orders 'hard starboard' and increases to 15 knots. The channel's starboard bank is 0.2 nautical miles away. The trawler's AIS destination field is blank, and her radar echo is small and intermittent.
1. Identify the status of each vessel from the lights and explain who must keep out of the way.
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Lights. Three all-round red lights mean a vessel constrained by her draught (COLREG Rule 28); she is not a vessel not under command. Red over white on the trawler means engaged in trawling. Who gives way? Ordinarily a power-driven vessel keeps out of the way of a vessel engaged in fishing (Rule 18(a)(iii)). But the tanker is constrained by draught and is in a narrow channel. Rule 9(b) says a vessel under 20 m shall not impede a vessel that can safely navigate only within the channel, and Rule 18(d) requires all vessels to avoid impeding a constrained-by-draught vessel displaying the lights. The trawler is therefore the vessel that must not impede. That does not free the tanker from Rule 8: if risk of collision exists, she must take positive action in ample time, and Rule 2 requires the ordinary practice of seamen. The tanker remains the stand-on vessel in practical terms, but 'stand-on' never means 'do nothing'.
2. Was the master's 'hard starboard' and speed increase defensible? What should the OOW have done?
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The order is not defensible. A hard starboard turn from the starboard edge of a 0.6 nm channel turns the tanker toward the bank only 0.2 nm away; squat and bank effect at 15 knots increase the grounding risk. Increasing speed shortens the time available and raises the energy of any collision. The VHF call is worse: the OOW says 'I am the give-way vessel' when the trawler is the vessel required not to impede, and he announces an intention to 'pass ahead' without knowing the trawler's course or speed. VHF is not a substitute for COLREG action; the reply was unintelligible and should have been read back. Correct action: reduce speed immediately, sound five short blasts (Rule 34(d)), switch to hand steering, and prepare to pass astern of the trawler. If the trawler fails to give way, take the best avoiding action, which may be a turn to port or a stop, but keep the vessel in the channel. Record the time, heading, speed and VHF channel.
3. After the near-miss, what evidence and legal steps should the Coast Guard take?
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Evidence: secure the VDR and simplified voyage data recorder, course recorder, AIS history, radar/ARPA, echo sounder, engine telegraph and bell book; record VHF 16 and working channel; take statements from the OOW, master, lookout and helmsman; photograph the trawler and the bank; test for alcohol under the Maritime Safety Act. The trawler's AIS is not required for a 14 m vessel in all waters, but her failure to keep a proper lookout and to not impede can be investigated. Legal steps: report the near-miss to the port state control/VTS; consider a violation of the Maritime Safety Act and COLREG; if there was no contact, this is not a collision case but a regulatory investigation. Do not arrest the master on the spot; the risk of flight is low and the evidence is documentary. Refer to the prosecutor with a reasoned opinion, and recommend a safety letter to the company about VHF reliance and speed in the channel.