24/02/2026
Main Engine Failure in a Busy TSS
Background: The container ship M/V Siam Star is transiting eastbound in a busy Traffic Separation Scheme (like the Singapore Strait). Suddenly, the main engine trips and cannot be restarted immediately. The vessel is losing speed rapidly and starting to drift towards the westbound lane.
The Communication
Vessel (Siam Star) [Broadcast to All Stations]: "Securite, Securite, Securite. All stations, All stations, All stations. This is M/V Siam Star in position [gives coordinates]. WARNING. I have major engine failure. I am Not Under Command (NUC). I am drifting towards the separation zone. Keep well clear of me. Over."
VTS Control: "Siam Star, this is VTS Control. Received your warning. QUESTION. What is your present drifting speed and direction? Over."
Vessel (Siam Star): "VTS Control, this is Siam Star. ANSWER. My present drifting speed is 2 knots, direction Southwest. INTENTION. I am preparing to drop anchors immediately to stop drifting into opposing traffic. Over."
VTS Control: "Received, Siam Star. INFORMATION. Tugs have been notified and are on standby. ADVICE. You should display Not Under Command lights/shapes immediately and maintain continuous watch on VHF Channel 16. Over."
Vessel (Siam Star): "VTS Control, received. NUC lights displayed. Watch maintained on Channel 16. Over."
Why this works:
Immediate Hazard Broadcast: The situation is dangerous to everyone, not just one ship. Starting with a safety signal (Securite) and a broadcast WARNING immediately alerts all nearby vessels that a dynamic hazard (a drifting, uncontrollable ship) has appeared.
Crucial Technical Status: Declaring "Not Under Command (NUC)" is vital. It legally informs other ships that, under COLREGs, they must now keep out of your way because you cannot maneuver.
Fact-Finding for Traffic Management: VTS uses QUESTION to get the exact data needed (drift speed/direction) to model the risk to other ships on their radar.
Critical Reactive Action: The vessel uses INTENTION to declare the most important immediate safety step: anchoring to stop the drift before crossing into oncoming traffic.
Procedural Reminders: VTS uses ADVICE to ensure the stressed bridge team doesn't forget essential legal requirements, like showing the correct NUC lights or day shapes.