VTS Core Nautical Knowledge 3 — Questions and Answers
Question 1: In IALA buoyage System B (used in the Americas), what color is the starboard-hand buoy when entering from seaward?
- Green
- Red (Correct answer)
- Yellow
- Black
Correct answer: Red
In IALA System B, red buoys mark the starboard side when entering from seaward, following the 'red right returning' mnemonic.
Question 2: What is 'squat' in the context of vessel navigation?
- A vessel's list to one side due to cargo shift
- The increase in a vessel's draft caused by its forward motion through water (Correct answer)
- The reduction in speed due to shallow water
- The tendency of a vessel to yaw in following seas
Correct answer: The increase in a vessel's draft caused by its forward motion through water
Squat is the hydrodynamic phenomenon where a moving vessel sinks deeper in the water, increasing its draft, especially pronounced in shallow or restricted waters.
Question 3: What does the term 'LOA' mean when referring to vessel dimensions?
- Load on Arrival
- Length Overall (Correct answer)
- Level of Anchorage
- Line of Approach
Correct answer: Length Overall
LOA stands for Length Overall, which is the maximum length of a vessel measured from the foremost to the aftermost point of the hull.
Question 4: A vessel displaying a black ball forward during daylight hours is indicating what?
- The vessel is engaged in trawling
- The vessel is at anchor (Correct answer)
- The vessel is not under command
- The vessel is constrained by draft
Correct answer: The vessel is at anchor
A single black ball displayed forward is the day shape for a vessel at anchor, as required by COLREGS Rule 30.
Question 5: In VTS, what is a 'mandatory reporting point'?
- A location where vessels must anchor for inspection
- A specific geographic position where vessels must report to VTS (Correct answer)
- A time schedule for regular radio check-ins
- A checkpoint where pilots must board all vessels
Correct answer: A specific geographic position where vessels must report to VTS
A mandatory reporting point is a designated geographic position, often marked on charts, where vessels are required to call VTS and report their position and intentions.
Question 6: What is 'freeboard' on a vessel?
- The distance from the keel to the waterline
- The distance from the waterline to the main deck edge (Correct answer)
- The total displacement of the vessel
- The height of the superstructure above the main deck
Correct answer: The distance from the waterline to the main deck edge
Freeboard is the distance measured from the waterline to the upper surface of the freeboard deck, indicating how much of the hull is above water.
Question 7: What signal does a vessel sound when operating in restricted visibility in a fog?
- One prolonged blast every 2 minutes (power-driven underway making way) (Correct answer)
- Three short blasts every 2 minutes
- One prolonged and two short blasts every 2 minutes
- Continuous ringing of a bell
Correct answer: One prolonged blast every 2 minutes (power-driven underway making way)
COLREGS Rule 35 requires a power-driven vessel making way in restricted visibility to sound one prolonged blast at intervals of not more than 2 minutes.
VTS Core Nautical Knowledge 3
In IALA buoyage System B (used in the Americas), what color is the starboard-hand buoy when entering from seaward?