China: Displaying Untrue Not Under Command (NUC) Signal Would Not Release Vessel’s Liability To Comply With International Regulations For Preventing Collisions At Sea (COLREGS)

Last Updated: 30 May 2014
Article by Xu Congbao and Qiu Yuhao

On 22 February 2012, there was a major collision between vessel MM and ZH off Hong Kong. The investigation has come to a conclusion, and now we think it is the time to review and share this case. Hopefully, similar cases can be avoided in the future through learning this tragic incident.

When vessels approached ports before schedule, growing numbers of seafarers, in breach of the COLREGS, like to use NUC signals while drifting off ports and terminals awaiting orders. Nearly every world's major port has seen such wrongful conduct where local authorities criticize this lazy habit and urge seafarers to comply with the COLREGS. In the collision between MM and ZH, ZH used NUC signals during their 12 hours waiting for berth. Their aim is straight. Through displaying NUC signals, other vessels would believe that ZH is a vessel in difficulty, and therefore the burden will be solely upon other vessels to take measures to avoid collision. The Master of ZH ordered his crew to display NUC signals through the vessel's Automatic Identification System (AIS) and to exhibit NUC shape on the vessel's mast. Half an hour before the accident when the Chief Officer came to take the control of the vessel, he expressed no objection to the NUC signals. Neither did other crew members that were in the wheel house at the time of the accident. Before the incident, the duty officer, the Chief Officer, was speaking with the sailor about his prospective retirement life without noticing the deteriorating visibility and approaching MM. The Master was walking around the wheel house, and he also did not recognize the risk of collision with MM. Two minutes before the accident, the Chief Officer heard the whistle of MM and asked the Second Officer what was the sound signals for NUC vessels. The Second Officer replied that there is no such signal as provided by COLREGS. Seconds before the accident, another prolonged blast was heard by all those in the wheel house but it was too late to avoid the collision.

Regarding MM, the vessel had been steering at about 17.5 knots by auto pilot until the collision happened. About 22 minutes before the accident, the Chief Officer sighted a fishing vessel narrowly cleared MM's starboard at a distance of only about 150 meters. At that time, there were dozens of radar targets, including ZH, lying ahead near MM's planned route. The Chief Officer's attention was heavily attracted by the nearby fishing vessel traffic. Although ZH was detected on the radar, the Chief Officer thought ZH was a fishing vessel, and he paid no special attention to it. About 19 minutes before the accident, as per the instruction of the Master, the Chief Officer started to execute Restricted Visibility Check List at the table. At the same time, he instructed the duty sailor to go outside the wheel house for watching the fishing vessels at MM's port side. Two minutes later, the visibility continued to deteriorate, and the Chief Officer ordered the duty sailor to sound fog whistles as per COLREGS. The sailor did so and MM had since then been sounding at an interval about 1 minute one prolonged blast. Afterwards, the Chief Officer once again ordered the sailor to check the fishing vessel on the vessel's port side. The sailor did so again failed to see anything due to the heavy fog. He reported the same to the Chief Officer and then came to the radar finding ZH was ahead at only 4 miles. He reported his finding but the Chief Officer only replied he was noted and continued his job of Restricted Visibility Check List. Seconds before the accident, the sailor shouted "a ship in front" but it was too late to avoid the collision.

The accident shows that abuse of NUC signals is not only against the COLREGS but also does little help for collision prevention. According to Rule 3(f) of the COLREGS, a "vessel not under command' is unable to maneuver in accordance with the Rules because some exceptional circumstance and is unable to keep out of the way of other vessels. The exceptional circumstance means main engine breakdown and likewise. However, waiting for berth by no means shall be considered as exceptional. At the material time, ZH was a power-driven vessel rather than NUC vessel. Therefore, ZH should have complied with the responsibilities as provided in Rule 18 of the COLREGS. ZH should not have used the NUC signals but show the appropriate lights and shapes according to Rule 23, 24, 25 and 26 of the COLREGS. Furthermore, according to Rule 35 of the COLREGS, in restricted visibility ZH should have sound at intervals of not more than 2 minutes two prolonged blasts in succession with an interval of about 2 seconds between them. MM also has fault and she did not maintain a proper look-out. However, consideration must be given to the fact that there were dozens of vessels ahead of MM, and ZH had not sounded fog whistles as per the COLREGS.

The accident should be noticed by shipowners, operators and all the seafarers that inappropriate use of NUC signals can result in severe collision. According to the COLREGS, vessels are not entitled to display NUC signals while drifting off ports and terminals awaiting for berth and must act as per responsibility of power-driven vessels prescribed in the Regulations.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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