Question 23 GLI05 - Master or Mate of LT 200 GRT

The Correct Answer is D The answer is derived directly from Rule 7 (Risk of Collision), specifically Rule 7(a)(i) of both the International Regulations for Preventing Collisions at Sea (COLREGs) and the Inland Rules. **Explanation for Option D (Correct):** Option D, "if the bearing of an approaching vessel does not appreciably change," is the primary and most definitive criterion stated in the Rules for determining if a risk of collision exists. Rule 7(a)(i) states: > "Such risk shall be deemed to exist if the compass bearing of an approaching vessel does not appreciably change." This is known as the "constant bearing, decreasing range" principle. If the bearing remains constant while the range decreases, the two vessels are on a collision course. **Explanation for Why Other Options are Incorrect:** * **A) whenever a vessel crosses ahead of the intended track of another vessel:** While crossing situations are dangerous and governed by specific rules (like Rule 15), they do not automatically deem that a risk of collision *exists* according to the Rule 7 definition. A vessel crossing ahead might be far enough away or proceeding fast enough that the bearing is changing rapidly, indicating no immediate risk. Risk is determined by the bearing change, not merely the geometric relationship. * **B) if one vessel approaches another so as to be overtaking:** Overtaking is a defined scenario (Rule 13), but like crossing (A), it does not automatically constitute a *deemed* risk according to Rule 7. An overtaking vessel might be passing far to the side of the overtaken vessel, causing the bearing to change constantly and rapidly, meaning there is no risk of collision even though the overtaking rule applies. * **C) whenever two vessels approach from opposite directions:** This describes a head-on situation (Rule 14), which is dangerous. However, if the vessels are slightly offset, their bearings will be changing (for example, if they will pass port-to-port or starboard-to-starboard with adequate CPA – Closest Point of Approach). Rule 7 requires a constant bearing to deem the risk of collision to exist.