AB Navigation Rules of the Road Questions and Answers — 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?
- You are the stand-on vessel and should maintain course and speed.
- The other vessel is the stand-on vessel, and you must give way. (Correct answer)
- You are in a head-on situation and should alter course to starboard.
- The other vessel is being overtaken and should maintain its course and speed.
Correct answer: The other vessel is the stand-on vessel, and you must give way.
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?
- A vessel constrained by her draft
- A sailing vessel underway
- A vessel not under command (Correct answer)
- A vessel engaged in fishing
Correct answer: A vessel not under command
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?
- A vessel at anchor.
- A power-driven vessel underway, making way.
- A vessel being towed.
- A vessel restricted in her ability to maneuver. (Correct answer)
Correct answer: A vessel restricted in her ability to maneuver.
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?
- A masthead light forward, sidelights, and a sternlight. (Correct answer)
- One all-round white light and sidelights.
- A masthead light forward, a second masthead light aft and higher, sidelights, and a sternlight.
- Sidelights and a sternlight only.
Correct answer: A masthead light forward, sidelights, and a sternlight.
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?
- Two short blasts.
- One short blast. (Correct answer)
- One prolonged blast.
- Five or more short and rapid blasts.
Correct answer: One short blast.
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.
Question 6: Which of the following day shapes should a vessel engaged in fishing, but not trawling, exhibit?
- One black ball.
- A cylinder.
- Two cones with their apexes together in a vertical line. (Correct answer)
- A diamond shape.
Correct answer: Two cones with their apexes together in a vertical line.
Rule 26 specifies that a vessel engaged in fishing, other than trawling, shall exhibit by day a shape consisting of two cones with their apexes together in a vertical line. This shape indicates its activity to other vessels during daylight hours.
AB Navigation Rules of the Road Questions and Answers
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?