AB Navigation & Watchstanding 4 — Questions and Answers
Question 1: When two power-driven vessels are meeting head-on in a narrow channel, the proper action is:
- Both vessels alter course to starboard so each passes on the other's port side (Correct answer)
- The vessel with the current on her port side is the stand-on vessel
- The larger vessel has the right of way and the smaller vessel must give way
- Both vessels stop and sound their signals until an agreement is reached by radio
Correct answer: Both vessels alter course to starboard so each passes on the other's port side
Rule 14 requires both power-driven vessels in a head-on situation to alter course to starboard so they pass port-to-port.
Question 2: A lookout is ordered to report a contact. The proper format for reporting a visual sighting is:
- Object name, color, and estimated size
- Relative bearing and description of the object (Correct answer)
- True bearing, distance, and ship name if readable
- Object type and time of sighting only
Correct answer: Relative bearing and description of the object
Lookouts report sightings using relative bearing (e.g., 'Red light, broad on the port bow') so the bridge team can immediately locate the contact.
Question 3: What is the significance of the term 'danger angle' in coastal navigation?
- The maximum angle of heel before a vessel becomes unstable
- A vertical or horizontal sextant angle that keeps a vessel clear of a hazard (Correct answer)
- The angle between the vessel's course and the direction of a current
- The bearing spread between two lighthouses that defines a safe lane
Correct answer: A vertical or horizontal sextant angle that keeps a vessel clear of a hazard
A danger angle is a sextant angle — horizontal (between two charted points) or vertical (of an object of known height) — set to keep the vessel outside a danger zone.
Question 4: Which statement about keeping a proper watch in port is correct?
- A full watch is only required when moored alongside a vessel carrying hazardous cargo
- The anchor watch is not required if the vessel is securely moored to a berth
- A watch must be maintained at all times, even when in port, to ensure safety and security (Correct answer)
- Only the engineer on watch is required; deck watches are optional in port
Correct answer: A watch must be maintained at all times, even when in port, to ensure safety and security
STCW and company SMS requirements mandate that a proper watch be kept at all times in port to guard against fire, flooding, unauthorized access, and other hazards.
Question 5: According to COLREGS, a vessel engaged in fishing with nets extending more than 150 meters horizontally shall exhibit:
- A white light in the direction of the gear in addition to prescribed fishing lights (Correct answer)
- Only the all-round red-over-white lights required of all fishing vessels
- A searchlight directed toward the gear plus anchor lights
- A yellow flashing light visible 360 degrees
Correct answer: A white light in the direction of the gear in addition to prescribed fishing lights
Rule 26 requires a vessel fishing with outlying gear extending more than 150 m to show an additional white light in the direction of the gear.
Question 6: A vessel steering 045°T with a current setting 270°T at 2 knots will experience what effect on her track?
- The current will set the vessel to the south, making good a track to the right of course
- The current will set the vessel to the north, making good a track to the left of course (Correct answer)
- No effect because the current is perpendicular to the course
- The vessel will be set directly ahead, increasing speed made good
Correct answer: The current will set the vessel to the north, making good a track to the left of course
A current from 270°T (west) flows eastward, pushing the vessel to the right (northward on a 045° heading), making good a track left of the intended course.
Question 7: When using a parallel ruler to transfer a course line to the compass rose on a nautical chart, the navigator walks the rulers from the course line to the nearest:
- True north meridian, reading the outer degree scale
- Center of the compass rose, reading the true bearing scale (Correct answer)
- Magnetic variation arrow, reading variation directly
- Coast line, using the bearing scale on the chart border
Correct answer: Center of the compass rose, reading the true bearing scale
The parallel rulers are walked carefully to the compass rose center so the course line direction can be read off the rose's true (outer) or magnetic (inner) scale.
AB Navigation & Watchstanding 4
When two power-driven vessels are meeting head-on in a narrow channel, the proper action is: