Loss of propulsion at night near Lei Yue Mun
At 22:40 a 20 m workboat is making 8 knots across a busy night-time fairway near Lei Yue Mun when the main engine stops and the lighting flickers before the emergency light comes on. The vessel is not under command, traffic is crossing ahead, and the chart shows rocky bottom in places with a useful anchorage about 0.4 nm to the west. The operator is alone on watch, the master is on the bridge, and the engine-room alarm panel shows low starting-air pressure and a tripped main breaker. There is no immediate smoke or water ingress. The VHF is on the port operations channel. The tide is setting the vessel towards the fairway. The operator has a torch and the engine-room tools but no external mechanic.
1. State your immediate actions in the first two minutes.
Read the worked answer
Keep control of the vessel first: steer a safe heading, warn the master, switch to emergency lighting, and display not-under-command lights and sound signals. Make a short VHF call to port operations and nearby traffic. Prepare the anchor and keep a lookout. Do not repeatedly crank the engine until you know why the breaker tripped and why starting-air pressure is low. Check for smoke or water ingress before entering the engine room. The aim is to prevent collision while buying time to diagnose the blackout.
2. How would you troubleshoot the blackout and decide whether to anchor?
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Check the fuel valves and supply, starting-air pressure, battery isolator, main breaker and emergency-stop circuit. Reset only once if the cause is obvious and safe; repeated resets can worsen an electrical fault. Because the vessel is being set towards the fairway and the bottom is rocky in places, anchor if drift cannot be corrected quickly. If the engine restarts and all pressures and temperatures are normal, move to clear water before investigating further. If not, remain anchored and arrange assistance. The decision turns on drift, traffic and holding ground, not on pride in fixing it alone.
3. What communications and records are required after the incident?
Read the worked answer
Send a PAN PAN or MAYDAY as appropriate if the vessel or persons are in danger; otherwise make a safety call to port control. State position, vessel name, nature of defect and intentions. Log the times of blackout, anchoring, calls and restart attempts. Report to the owner or company and follow local reporting requirements. After the incident, inspect the breaker, starting-air system and fuel supply before the vessel resumes normal service. The records should allow a relief operator to understand what happened and what remains suspect.