Question 19 TV02 - Towing Vessels - Great Lakes and Inland

The Correct Answer is A. A vessel is on your starboard quarter, range decreasing, bearing is constant. ### Why Option A is Correct According to Rule 7(a)(i) of the International Regulations for Preventing Collisions at Sea (COLREGs), risk of collision shall be deemed to exist if the Compass Bearing of an approaching vessel does not appreciably change (i.e., the bearing is constant). The combination of: 1. **Constant Bearing:** Indicates that the vessels are on a collision course if they continue their current speed and direction. 2. **Decreasing Range:** Confirms that the vessels are actively moving closer together. This specific scenario—Constant Bearing, Decreasing Range (CBDR)—is the definitive sign of a collision risk, regardless of the relative position of the approaching vessel (though in this case, a vessel overtaking from the quarter is confirming the risk). ### Why Other Options Are Incorrect **B) A vessel is 22 degrees abaft your port beam, range increasing, bearing is constant.** * **Bearing is Constant (Risk Indicator):** Suggests a collision course. * **Range is Increasing (No Risk):** The increasing range overrides the constant bearing indication. If the vessel is moving away, there is no risk of collision, even if the bearing is momentarily constant. **C) A vessel is broad on your starboard beam, range decreasing, bearing changing rapidly to the right.** * **Bearing is Changing Rapidly:** A significant change in bearing indicates the vessels are not on a collision course (they will pass clear). * **Range is Decreasing:** Although they are getting closer, the changing bearing confirms they are converging but will not meet at the same point (they will pass ahead or astern of each other). **D) A vessel is 22 degrees on your port bow, range increasing, bearing changing slightly to the right.** * **Range is Increasing:** The vessel is moving away, eliminating the risk of collision. * **Bearing is Changing:** Confirms they are not on a collision course. Both indicators show that risk of collision does not exist.