AB Navigation Rules of the Road Questions and Answers

Question 1

You are on a power-driven vessel underway at night and observe the lights of another vessel off your port bow. You see a green sidelight and a white masthead light. The aspect of these lights does not change over time. Which of the following is TRUE?

Accepted Answer

The other vessel is the stand-on vessel, and you must give way.

Answer

This is a classic crossing situation under Rule 15. The vessel that has the other on her own starboard side is the give-way vessel. Since you see the other vessel's green light off your port side, you are the give-way vessel and are required to take early and substantial action to keep well clear, which usually involves altering course to starboard to pass astern of the other vessel. The other vessel is the stand-on vessel and is required by Rule 17 to maintain her course and speed.

Question 2

Under the Navigation Rules, which of the following vessels has the highest priority and right-of-way over all other vessels?

Accepted Answer

A vessel not under command

Answer

Rule 18 outlines the hierarchy of responsibility between vessels. A vessel not under command (NUC) is unable to maneuver as required by the rules and therefore cannot keep out of the way of other vessels. Consequently, all other vessels (including those fishing, sailing, or power-driven) must keep out of her way.

Question 3

You are underway in fog and hear one prolonged blast followed by two short blasts from another vessel. What does this signal indicate?

Accepted Answer

A vessel restricted in her ability to maneuver.

Answer

According to Rule 35 (Sound Signals in Restricted Visibility), a vessel restricted in her ability to maneuver, when carrying out her work at anchor or underway, shall sound at intervals of not more than 2 minutes one prolonged blast followed by two short blasts. This signal identifies the vessel's special status to others in low visibility.

Question 4

A 25-meter power-driven vessel, when underway at night, must exhibit which of the following lights as a minimum?

Accepted Answer

A masthead light forward, sidelights, and a sternlight.

Answer

Rule 23 states that a power-driven vessel underway shall exhibit a masthead light forward, sidelights (a green one on the starboard side and a red one on the port side), and a sternlight. A second masthead light abaft of and higher than the forward one is only required for vessels 50 meters or more in length.

Question 5

You are on Vessel A and are overtaking Vessel B in a narrow channel. You intend to pass on Vessel B's starboard side. Under the Inland Rules, what is the correct whistle signal to propose this action?

Accepted Answer

One short blast.

Answer

Under Inland Navigation Rule 9, when overtaking in a narrow channel, the overtaking vessel must signal its intention. One short blast indicates 'I intend to leave you on my port side' (meaning you will pass on their starboard side). Two short blasts would mean 'I intend to leave you on my starboard side' (passing on their port side). The overtaken vessel would sound the same signal if in agreement.

(AB) Able Seaman Exam Practice Test

(AB) Able Seaman Exam Practice Test

AB Navigation Rules of the Road Questions and Answers