Crossing the East Lamma Channel at Night
At 2140 on a clear night with visibility 5 nm, you are the master of a 12 m motor cruiser making 9 knots on course 270°T across the East Lamma Channel, from Lamma Island towards Hong Kong Island. Wind is SE 12 knots, sea slight. Radar and AIS are working. A 35 m local ferry is bearing 300°T at 1.2 nm; its bearing is steady and the range is falling. AIS shows a CPA of 0.1 nm and TCPA of 4 minutes. The ferry is not showing RAM, NUC or constrained-by-draft signals. To your port side, a 60 m high-speed passenger craft is proceeding west in the main fairway at about 25 knots, still 1.5 nm away. Your VHF is on channel 16 and 12. The channel is busy with cross-harbour traffic, and there is a line of moored craft close to your starboard side. You have not yet altered course or speed.
1. Assess the crossing situation with the ferry and state who must give way. What action do you take, and what sound signal, if any, would you make?
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Both vessels are power-driven and in sight. The ferry bears about 30° on your starboard bow, its bearing is steady and range is decreasing, so Rule 7 risk of collision exists. Under Rule 15 you are the give-way vessel. Rule 16 requires early and substantial action: reduce speed and/or alter course to pass astern of the ferry with a safe CPA; do not make a small last-minute alteration. Check the bearing after the alteration and keep a visual lookout. A starboard alteration is the usual starting point, but the high-speed craft on your port side and the moored craft to starboard mean the geometry must be checked before turning; a reduction of speed may be the safest first action. If altering course to starboard, sound one short blast (Rule 34(a)); sound three short blasts if operating astern propulsion. Do not assume the ferry is stand-on merely because it is a local ferry; apply the hierarchy and check for RAM, NUC or constrained-by-draft signals.
2. The high-speed craft is approaching from your port side at 25 knots. Does that change your obligation? Explain how you sequence the two conflicts.
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The high-speed craft is on your port side, so in a crossing with it you are the stand-on vessel; it should give way. But you are already give-way to the ferry. You cannot satisfy both by a blind turn. First determine which risk is developing faster: the ferry has a 4-minute TCPA and a 0.1 nm CPA, so it is the immediate threat. A reduction of speed lets the ferry pass ahead and also opens the CPA with the high-speed craft. If you alter, a starboard alteration turns away from the high-speed craft on your port side, but it may turn toward the ferry on your starboard side, so verify with bearings. As stand-on vessel you must initially keep course and speed, but Rule 17 allows action when it is clear the give-way vessel is not taking action; avoid altering to port for a vessel on your port side if possible. Make one clear, early manoeuvre, sound the appropriate signal, and monitor both targets.