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These 10 free NM1GI questions are organized by exam domain, so you can see how each part of the National Master 100 GL and Inland (NM1GI) blueprint is tested. Reveal the answer and explanation under each question.
In open U.S. inland waters, a power-driven vessel on your port side is crossing your power-driven vessel's course with risk of collision. It makes an early, substantial alteration to pass astern. Your observations confirm a safe passing distance, and no other traffic or hazard requires a maneuver. What should you do while the crossing is completed?
Correct answer: B - Maintain course and speed, continuing to monitor the passage.
Two power-driven vessels are meeting in a narrow fairway on the U.S. waters of the Great Lakes. One is downbound with a following current; the other is upbound against it. Under the Inland Rules, which vessel proposes the manner and place of passage and initiates the appropriate maneuvering signals?
Correct answer: A - The downbound vessel proceeding with the following current.
At night, a working dredge displays three all-round lights vertically: red, white, red. It also shows two all-round red lights vertically on one side and two all-round green lights vertically on the other. What do the additional red and green pairs tell an approaching vessel?
Correct answer: C - The green pair marks the passing side; the red pair marks the obstructed side.
While proceeding ahead close to a channel's starboard bank, a vessel's bow sheers to port and its stern moves toward the bank. The helm and engine settings have not changed, and there is no appreciable wind. Which explanation best accounts for both movements?
Correct answer: D - Bank cushion acting at the bow and bank suction acting at the stern.
An anchor alarm sounds after a wind shift. Successive fixes trace an arc around the recorded anchor position, then settle within the anticipated swinging circle. Bearings of fixed shore objects become steady, and the vessel remains clear of nearby boats and shoals. Which response fits these observations?
Correct answer: D - Continue the anchor watch, checking repeated fixes and shore bearings.
A fixed CO2 system has just discharged into a burning engine compartment. Everyone is accounted for outside the space; engines, fuel supplies and ventilation are secured, and the access hatch is closed. As escaping smoke diminishes, a deckhand asks to open the hatch to see whether the fire is out. Your immediate instruction is to:
Correct answer: C - Keep the space closed and monitor its boundaries for heat and fire spread.
Stores are moved from a low centerline compartment to the centerline of an upper deck. Displacement is unchanged, but corrected metacentric height (GM) decreases from +1.2 feet to +0.4 feet. Compared with the original loading, what should you expect during small-angle rolling in similar conditions?
Correct answer: B - A weaker initial righting tendency and a generally slower roll.
Approaching a channel junction in the charted conventional direction of buoyage, you identify a U.S. buoy with red and green horizontal bands, an uppermost red band, and a red composite group-flashing (2+1) light. How is the preferred channel marked?
Correct answer: A - It branches to port; leave this buoy to starboard when taking that branch.
Your current correction calls for a heading of 120 degrees true to maintain a ground track of 112 degrees true. Variation is 6 degrees west, and the deviation card gives 3 degrees east at the required heading. What compass heading should you order?
Correct answer: D - 123 degrees compass.
A ferry must make good a track of 000 degrees true between two river landings. Its speed through the water is 5.0 knots, and a steady current sets 090 degrees true at 3.0 knots. Neglect wind and leeway. Which heading and speed over ground are closest to those required?
Correct answer: C - Heading 323 degrees true; speed over ground 4.0 knots.
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