Question 17
ONC03INTERNATIONAL ONLY Which light(s) shall a single vessel being towed alongside show?
AI Explanation
The Correct Answer is B
**Explanation for Option B (Sidelights and a stern light):**
This requirement is mandated by the International Regulations for Preventing Collisions at Sea (COLREGs), specifically Rule 24(f). Rule 24(f) governs the lights shown by a vessel being towed. It states that such a vessel must exhibit the lights prescribed in Rule 23 (lights for a power-driven vessel underway) **except** that it shall not exhibit the masthead light(s).
The standard lights for a power-driven vessel underway (Rule 23) are:
1. Masthead light(s)
2. Sidelights
3. Stern light
By excluding the masthead light(s), the single vessel being towed alongside must show only the **sidelights and a stern light**.
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**Explanation of why other options are incorrect:**
* **A) One all-round white light:** This light configuration is typically reserved for small vessels (less than 7 meters) or vessels at anchor/aground, not for a vessel being towed underway alongside a tug.
* **C) A masthead light, sidelights, and a stern light:** This option includes the masthead light. Rule 24(f) explicitly mandates that vessels being towed *shall not* exhibit the masthead light(s).
* **D) Only the outboard sidelight and a stern light:** A vessel being towed must exhibit both sidelights as part of the required Rule 23 configuration (less the masthead light). There is no provision in the general rules for a towed vessel to show only the outboard sidelight.