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These 10 free USCG-A/B questions are organized by exam domain, so you can see how each part of the National Able Seaman (A/B) blueprint is tested. Reveal the answer and explanation under each question.
In clear weather under the International Rules, your power-driven vessel is approaching another power-driven vessel on crossing courses with risk of collision. The other vessel, on your port side, takes early and substantial action to pass safely astern. What is your vessel's proper role at this stage?
Correct answer: B - Maintain course and speed while monitoring the other vessel's passage.
At night under the International Rules, a 65-meter ship shows two all-round red lights in a vertical line. She also shows an all-round white light forward and another all-round white light near the stern, lower than the forward white light. Which status accounts for the complete display?
Correct answer: A - Aground
The bridge needs a heading of 124° true. Local variation is 8°W, and the deviation card gives 3°E for the intended heading. The helmsman is steering by magnetic compass. What compass heading corresponds to the required true heading?
Correct answer: C - 129° compass
Two power-driven vessels are meeting nearly head-on in clear weather on U.S. Inland waters, within half a nautical mile. The approaching vessel sounds one short blast. Your vessel agrees to the proposed safe port-to-port passage. How should your vessel answer?
Correct answer: A - One short blast.
During inspection of a float-free liferaft, an AB finds that the painter's specified weak link has been replaced with a strong wire strop. The hydrostatic release and all other connections are correctly fitted. Which part of the float-free sequence is most directly jeopardized?
Correct answer: B - Separation of the inflated raft before it is pulled under by the ship.
A light heaving line must be temporarily joined end-to-end to a much heavier messenger so the messenger can be hauled ashore. Which connection is designed for joining these unequal-sized lines?
Correct answer: D - Double becket bend
An oily-water separator's monitor reads 8 ppm while machinery-space bilge water is being discharged into a U.S. harbor. A fresh oil sheen appears at the discharge outlet. How should the crew respond to these apparently conflicting indications?
Correct answer: C - Stop the discharge and promptly notify the responsible officer.
A vessel remains close alongside the pier but begins surging ahead. Which mooring line is specifically led to check that forward movement?
Correct answer: B - A spring leading aft from the forward mooring station.
The fire-party leader calls for a portable extinguisher for burning oil in a galley deep-fat fryer. Under the U.S. fire-classification system, which agent is specifically suited to this fire?
Correct answer: D - Class K wet chemical
An anchored ship has 270 ft of chain between the hawse and the anchor. Water depth is 36 ft, measured from the surface to the seabed. The tide will rise another 9 ft, and the hawse will remain 9 ft above the surface. With adequate swinging room, how much more chain is needed to meet the bridge's ordered minimum scope of 6:1 at high water?
Correct answer: A - 54 ft
The USCG-A/B exam also covers these domains. Drill them in the full free practice test:
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