Question 32
ONC06BOTH INTERNATIONAL & INLAND Which of the following describes a vessel exhibiting the lights shown in illustration D084RR below?

AI Explanation
The Correct Answer is A.
### Why Option A ("not under command") is Correct
The illustration D084RR (which depicts a vessel exhibiting the lights for a vessel **not under command**) shows the following configuration:
1. **Two all-round red lights displayed one vertically over the other.**
According to the International Regulations for Preventing Collisions at Sea (COLREGs) Rule 27(a) and the Inland Rules equivalent:
* A vessel **not under command (NUC)**—meaning she is unable to maneuver as required by the Rules due to some exceptional circumstance—must exhibit **two all-round red lights** in a vertical line where they can best be seen.
* If the vessel is making way through the water, she must also exhibit sidelights and a sternlight. If she is stopped, she exhibits only the two red lights.
The lights described (two vertical all-round red lights) are the defining characteristic signal for a vessel **not under command** for both International and Inland application.
### Why the Other Options Are Incorrect
**B) showing improper lights:**
While a vessel could be showing improper lights, the configuration of two vertical all-round red lights is a standard, defined signal under the Rules. Therefore, the lights themselves are proper and clearly define a specific status (Not Under Command).
**C) dredging:**
A vessel engaged in **dredging** (or underwater operations) exhibits:
* Three all-round lights in a vertical line: Red-White-Red.
* When restricted in ability to maneuver by the operation, she also shows the standard masthead lights, sidelights, and sternlight (if over 50 meters).
This signal (R-W-R) is distinct from the two vertical red lights (R-R) shown by the NUC vessel.
**D) towing:**
A vessel engaged in **towing** exhibits:
* Two or three masthead lights in a vertical line (depending on the length of the tow).
* Standard sidelights and sternlight.
* A vertical yellow over white light at the stern (the towing light).
This combination of lights is entirely different from the two vertical all-round red lights.