Rules of the Road & Maritime Regulations Flashcards

What is the arc of visibility for a vessel's sidelights?

Answer: 112.5 degrees each side

Rule 21 defines sidelights as showing from dead ahead to 22.5 degrees abaft the beam — an arc of 112.5 degrees on each side.

A vessel towing where the length of tow exceeds 200 meters displays which special day shape?

Answer: A black diamond

Rule 24 requires a vessel towing where the length of tow exceeds 200 meters to display a black diamond shape where it can best be seen.

Which rule of the COLREGS establishes the duty to maintain a proper lookout?

Answer: Rule 5

Rule 5 requires every vessel to maintain a proper lookout by sight and hearing, as well as by all available means, at all times.

A vessel using a traffic separation scheme must generally proceed in which direction?

Answer: In the general direction of traffic flow for that lane

Rule 10(b) requires vessels using a traffic lane to proceed in the general direction of traffic flow for that lane.

Under COLREGS, what is the difference between a 'short blast' and a 'prolonged blast'?

Answer: Short = 1 sec; Prolonged = 4–6 sec

Rule 32 defines a short blast as about one second duration and a prolonged blast as from four to six seconds duration.

When vessels are in sight of one another, a power-driven vessel altering course to starboard sounds what signal?

Answer: One short blast

Rule 34 requires one short blast to indicate 'I am altering my course to starboard' when vessels are in sight of each other.

A vessel aground shows which additional light or shape beyond anchor lights?

Answer: Two red lights in a vertical line and three black balls

Rule 30(d) requires a vessel aground to exhibit anchor lights plus two all-around red lights in a vertical line and three black balls in a vertical line by day.