Question 249General Subjects - 1st Asst/Chief

The correct answer is A) Operation of the main propulsion machinery, ahead and astern. According to 33 CFR 164.25, vessels must test their main propulsion machinery, including operation ahead and astern, prior to getting underway on the navigable waters of the United States, within 12 hours. This is a critical safety requirement to ensure the vessel's main propulsion system is functioning properly before departing. The other options are incorrect because they do not relate to the specific pre-departure tests required by 33 CFR 164.25. Options B, C, and D describe tests of other machinery, such as the main engine's low lube oil pressure trip, the emergency generator's reverse power relay, and the ship service diesel generator's overspeed trip, which are not part of the mandatory pre-departure tests outlined in the regulations.