STCW Navigation & Watchkeeping Practices 5 — Questions and Answers
Question 1: What does a vessel display to indicate it is 'not under command' under COLREGS?
- Two all-round red lights in a vertical line and no sidelights when stopped (Correct answer)
- One all-round red light at the masthead
- A black ball shape at the bow
- Three all-round red lights in a vertical line
Correct answer: Two all-round red lights in a vertical line and no sidelights when stopped
Rule 27 requires a vessel not under command to display two all-round red lights vertically; sidelights and sternlight are only shown when making way.
Question 2: When conducting a passage plan, the 'monitoring' phase refers to which activity?
- Checking weather forecasts before departure
- Tracking the vessel's actual progress against the planned route during the voyage (Correct answer)
- Reviewing the plan with all officers before departure
- Updating charts and publications after the voyage
Correct answer: Tracking the vessel's actual progress against the planned route during the voyage
The monitoring phase involves continuously comparing the vessel's actual position and progress against the pre-planned route throughout the voyage.
Question 3: A vessel hears five or more short blasts from another vessel. What does this signal mean?
- The vessel is in distress and requires assistance
- The signal is a danger/doubt signal indicating the other vessel does not understand your intentions (Correct answer)
- The vessel is altering course to starboard
- The vessel is operating in a TSS and requires priority passage
Correct answer: The signal is a danger/doubt signal indicating the other vessel does not understand your intentions
Rule 34(d) specifies that five or more short rapid blasts is the danger signal, indicating doubt about the other vessel's intentions or actions.
Question 4: Which type of current most significantly affects a vessel's set and drift in coastal navigation?
- Wind-driven surface current only
- Tidal current (Correct answer)
- Subsurface thermohaline current
- Rip current in open ocean
Correct answer: Tidal current
Tidal currents are the primary predictable current affecting coastal navigation and must be accounted for in passage planning and position monitoring.
Question 5: Under STCW, an OOW may be the sole lookout during the day under which condition?
- Never — a separate lookout is always required
- Only when the vessel is in open ocean with no traffic
- After a full risk assessment concludes it is safe and the master has authorized it (Correct answer)
- When the vessel is on autopilot and ARPA is active
Correct answer: After a full risk assessment concludes it is safe and the master has authorized it
STCW allows the OOW to be the sole lookout in daylight only after a risk assessment confirms it is safe, with the master's explicit authorization.
Question 6: What is a 'waypoint arrival alarm' in ECDIS and why is it critical for watchkeeping?
- An alarm that activates when the vessel deviates beyond a set cross-track limit
- An alarm triggered as the vessel approaches a waypoint, alerting the OOW to take a course alteration action (Correct answer)
- An alarm that notifies the master when approaching port limits
- An alarm set for watch relief timing
Correct answer: An alarm triggered as the vessel approaches a waypoint, alerting the OOW to take a course alteration action
The waypoint arrival alarm warns the OOW that a course alteration is required, ensuring the vessel follows the planned track through each waypoint.
Question 7: What is the significance of the 'Precautionary Area' designation in route planning?
- An area where anchoring is prohibited by port authority decree
- An area where vessels must exercise particular caution and may navigate in any direction, often near TSS junctions (Correct answer)
- A zone requiring mandatory pilotage for all foreign vessels
- An area designated for search and rescue operations only
Correct answer: An area where vessels must exercise particular caution and may navigate in any direction, often near TSS junctions
A Precautionary Area requires special caution from mariners and is typically found at the junction of TSS routes where traffic from multiple directions converges.
STCW Navigation & Watchkeeping Practices 5
What does a vessel display to indicate it is 'not under command' under COLREGS?