200443 Displaying NUC Lights

Displaying NUC Lights
MARS Report 200443

I recently had an interesting discussion on the bridge of a cruise ship with North European Deck Officers. As with many other such vessels, it is common practice to proceed sufficiently far from shore to discharge food waste and grey water

(Outside a special area! Ed.).

Passage times are often so short that much of the time the main engines are stopped and, once the discharge of waste is completed, the ship drifts until it is necessary to resume the passage.

The Master stated that he required the "Not Under Command" (NUC) lights to be exhibited while the ship was drifting. Many of these vessels exhibit NUC lights while drifting. I queried the legality of this and suggested that stopping by choice did not make the ship "not under command" as defined by Rule 3 (f), which requires the inability to manoeuvre due to some exceptional circumstance. The Master insisted that the ship was not under command if the main engines were not available immediately, whatever the cause. His concern was that, with the engines stopped, the ship would not be able to manoeuvre to avoid a collision. The obvious answer is to have the main engines available at sufficiently short notice to enable any necessary action to be taken. If stopping the main engines places the ship into any danger, they should not be stopped, or at least be kept at instant readiness. A discussion followed and a copy of the International Regulations for the Prevention of Collisions art sea was produced.
Rule 3(i) defining a vessel underway seemed clear enough as did Rule 23(a) defining the lights to be exhibited by a vessel underway. Whether the vessel is making way or not is immaterial. The question of whether or not to extinguish the side lights once the vessel was no longer making way then arose.

The officers remained divided in their interpretation of the requirement to show side lights if not actually making way and, to settle matters, sought the opinion of their National Maritime Authority.

The reply is interesting and the last sentence conflicts with my interpretation of the Rules.

Dear Sirs,

Reference is made to your e-mail of??? with questions of how to read Rule 27. Please note that the definition of a vessel not under command" is given in Rule 3 (f).

In order to conclude:

If you have stopped your engines just to kill time, with the engines ready, the NUC lights should not be exhibited. The normal running lights should be shown. If the ship does not make way through the water the sidelights should not be exhibited.

I hate to disagree with a Senior Principal Surveyor, buy I do not agree with the statement that side lights should be extinguished if the vessel is not making way through the water. As I read Rule 23(a), side lights should be exhibited by a normal power driven vessel under way. As a lecturer, preparing candidates for their MCA Oral Examinations, this is what I taught. As a final thought, the prospect of half a dozen cruise ships, each carrying around two or three thousand passengers, all drifting in relatively close proximity off a port, arouses some concern, especially if they all consider themselves to be Not under Command.

Readers' Feedback

1 A suggestion which appears to comply with the rules for displaying lights is for vessels who, by the nature of their work are "drifting awaiting berthing" or "carrying out (routine) main engine maintenance" to display Restricted in Ability to Manoeuvre signals. They ARE capable of manoeuvring (perhaps with significant delay) but to do so would interfere with their "work", in just the same way as for other RAM vessels. It is immaterial that this is not their prime "work" as these signals are routinely shown (e.g. for helicopter operations) by non dedicated vessels. This would appear to be well within the spirit of the law and clearly indicates to approaching vessels that they should not expect the same manoeuvres as could be expected from a power driven vessel underway. It will be interesting to see if any consensus can be reached!

2 I believe that the author of this particular report is absolutely correct in his interpretation of the rules. What I find disappointing is that a so-called reputable flag state disagrees with him. What hope is there? I am pleased that the UK administration does agree with the authors interpretation as I have had official communication with them on this topic in the past. There is only one solution for the foreseeable future. "Sail Defensively".

3. It seems pretty straightforward that "convenience" does not purport to be "an unusual circumstance", thus NUC lights are not warranted in the given situation. Additionally, and for exactly the same reason, extinguishing side lights under that situation would be equally illegal. The Rules take great pains to distinguish "underway" from "underway and making way" for NUC/ RAM (Rule 27-b-iii) and Fishing (26-c-iii) ID lights - in those cases sidelights not being shown unless making way. It follows then that since the vessel in question is just a "plain-vanilla" Power Driven Vessel underway - all appropriate running lights are mandated, way-on or not.

4. I read with interest "Mars 20043" and was astonished that a Senior Principal Surveyor could write such a nonsense. A power driven vessel underway, even when not making way through the water, should exhibit the lights prescribed in rule 23.