Question 8 LB01 - Lifeboat Operator

The Correct Answer is D **Explanation for Option D (All of the above):** Option D is correct because all three listed precautions (A, B, and C) are critical procedures necessary for the safe and accurate use of a lifeboat compass. **A) set it on the centerline of the boat:** To obtain accurate magnetic readings, the compass should be placed as close as possible to the boat's fore-and-aft centerline. This minimizes the deviation caused by the boat's structure (if any significant metallic components exist) and ensures the lubber line (the mark indicating the vessel's heading) is aligned with the vessel's axis. **B) keep metal objects away from it:** This is the most fundamental rule of compass use. Ferrous metal objects (like knives, tools, radio equipment, or even keys and belt buckles) create magnetic fields that interfere with the Earth's magnetic field, causing **deviation error** and rendering the compass reading inaccurate. In a survival situation, accurate navigation is paramount. **C) apply the correction for compass error:** A compass reading (Compass Course - CC) is rarely the true course (True Course - TC). To convert from CC to TC, you must apply corrections for both **variation** (the difference between true north and magnetic north, found on charts) and **deviation** (the error caused by magnetic interference from the vessel itself). While lifeboats are designed to minimize deviation, all navigation requires accounting for the total compass error. Since A, B, and C are all necessary precautions when using a lifeboat compass, D is the correct choice. **Explanation of Incorrect Options:** While A, B, and C are true statements regarding compass use, they are **not incorrect**—they are just incomplete answers when presented individually as the primary choice. * **A) set it on the centerline of the boat:** This is a necessary step, but it ignores the equally critical issues of metallic interference and applying error corrections. * **B) keep metal objects away from it:** This is a vital precaution, but it is insufficient alone, as setting the compass properly and correcting the reading are also mandatory for accuracy. * **C) apply the correction for compass error:** This is required for accurate navigation, but if the compass is improperly placed (A) or affected by external magnetic fields (B), the correction applied will be meaningless.