USCG Deck Navigation (Supplementary)
Module Code: USCG NAV-SUPP • 146 verified questions across 5 practice sets with 46 CFR and engineering rule citations. Completely free with zero paywalls.
USCG Deck Navigation (Supplementary) Practice Sets
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USCG NAV-SUPP Practice Set 1
Full questions with verified 46 CFR rule explanations.
USCG NAV-SUPP Practice Set 2
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USCG NAV-SUPP Practice Set 3
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USCG NAV-SUPP Practice Set 4
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USCG NAV-SUPP Practice Set 5
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Sample USCG Deck Navigation (Supplementary) Questions & Solutions
Preview authentic USCG NMC exam questions from this module with verified answers and rule citations.
The principal purpose of magnetic compass adjustment is to __________.
Magnetic compass adjustment compensates for the ship's permanent and induced magnetism. Deviation is the error caused by the vessel's own magnetic field, which varies by heading. Adjusting the compass using magnets and soft iron correctors minimizes this deviation, ensuring the compass remains a reliable navigational instrument for steering and bearings.
While steaming on course 280°T, you sight a buoy showing a very quick-flashing (VQ) white light well to port. Maintaining course, you sight another buoy showing a quick-flashing (Q) white light. You should pass __________.
Under IALA cardinal buoyage, a North cardinal mark indicates the safest water lies to the north. A VQ light (continuous) signifies a North mark, while a Q light (group of 3) signifies an East mark. To remain in safe water, you must pass to the north of the North cardinal buoy.
The characteristic of a lighted cardinal mark may be __________.
IALA cardinal marks utilize specific light characteristics to indicate their orientation. North marks show continuous very quick (VQ) or quick (Q) flashes. East marks show group flashing (3), South marks show group flashing (6) plus a long flash, and West marks show group flashing (9). Thus, very quick flashing is a valid characteristic.
You are underway on course 142°T when you sight a buoy bearing 105°T. The buoy's white light has a characteristic of continuous very-quick flashing. To ensure that your vessel remains in the best navigable water you would __________.
A continuous very-quick flashing light identifies a North cardinal mark. Per IALA standards, cardinal marks indicate the side of the buoy on which the safest water lies. A North cardinal mark signifies that the best navigable water is to the north; therefore, you must alter course to pass north of it.
You are underway in the North Sea on course 216°T when you sight a buoy bearing 021° relative. Under the IALA Buoyage System, you are in the best navigable water if the buoy __________.
The light characteristic Q(6) + L Fl 15s identifies a South cardinal mark under the IALA system. South cardinal marks indicate that the safest water lies to the south of the mark. Since you are on course 216°T and the buoy is to your north, passing south of it keeps you safe.
On approaching the English Channel on course 080°T, you note the symbol YBY near a charted buoy. You must pass __________.
A YBY (Yellow-Black-Yellow) horizontal band pattern identifies a West cardinal mark. Under the IALA buoyage system, a West cardinal mark indicates that the safest water lies to the west of the mark. Consequently, you must pass westward of the buoy to remain in the best navigable water for your vessel.
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