Navigation & Watchstanding Flashcards

When standing a proper lookout at night, which method of viewing is most effective for detecting dim objects?

Answer: Off-center or peripheral vision slightly away from the object

At night, rod cells in the peripheral retina are more sensitive to low light, so looking slightly off-center (eccentric viewing) reveals dim objects better than direct central vision.

A vessel is required to proceed at a safe speed. Which factor is NOT listed under COLREGS Rule 6 for determining safe speed?

Answer: The experience level of the helmsman

COLREGS Rule 6 lists visibility, traffic density, maneuverability, and background lights as factors, but the helmsman's experience level is not included.

You are on watch and the vessel's magnetic compass reading differs from the gyrocompass by more than 2 degrees compared to the last logged error. What should you do first?

Answer: Report the discrepancy to the officer of the watch and note it in the log

Any significant change in compass error must be reported to the OOW and logged so it can be investigated; the watch officer decides the appropriate action.

According to the International Regulations for Preventing Collisions at Sea, a vessel is considered to be 'underway' when she is:

Answer: Not at anchor, not made fast to shore, and not aground

COLREGS Rule 3 defines 'underway' as not at anchor, not made fast to shore, and not aground — regardless of whether the vessel is moving.

While keeping a radar watch in restricted visibility, you detect a vessel fine on your starboard bow with a steady bearing and decreasing range. According to COLREGS, you should:

Answer: Reduce speed, stop, or take all way off as necessary

In restricted visibility, Rule 19 requires reducing speed to bare steerage, stopping, or taking all way off when a close-quarters situation may develop — normal crossing rules do not apply.

What is the primary purpose of plotting a running fix when only one landmark is available?

Answer: To obtain a position using two bearings of the same object taken at different times

A running fix advances an earlier bearing line along the vessel's track to cross a new bearing of the same object, yielding a position with a single landmark.

On a vessel with a conventional rudder, when the order 'hard right rudder' is given, the bow will initially swing to the right and the stern will:

Answer: Swing to the left (port)

When the rudder is put hard right, the stern kicks to port (left) as the bow swings to starboard — the ship pivots about a point roughly one-third aft of the bow.