STCW Navigation & Watchkeeping Practices 4 — Questions and Answers
Question 1: What does ARPA stand for and what is its primary watchkeeping function?
- Automatic Radar Plotting Aid — tracks targets and calculates CPA/TCPA (Correct answer)
- Advanced Radio Position Apparatus — determines GPS position
- Automated Route Planning Assistant — manages ECDIS routing
- Absolute Radar Position Alarm — alerts when off-track
Correct answer: Automatic Radar Plotting Aid — tracks targets and calculates CPA/TCPA
ARPA automatically tracks radar targets and calculates their Closest Point of Approach (CPA) and Time to CPA (TCPA) to assess collision risk.
Question 2: A power-driven vessel meeting another power-driven vessel head-on should take which action under COLREGS?
- Both vessels alter course to starboard (Correct answer)
- The vessel with the other on its port bow gives way
- The slower vessel gives way to the faster vessel
- Both vessels alter course to port
Correct answer: Both vessels alter course to starboard
Rule 14 requires both vessels in a head-on situation to alter course to starboard so each passes on the port side of the other.
Question 3: When should an OOW call the master, according to STCW and standing orders?
- Only in an emergency requiring abandon ship
- When visibility drops below 5 nautical miles
- Whenever in doubt about safety, or when defined threshold conditions are met (Correct answer)
- Only when entering or leaving port
Correct answer: Whenever in doubt about safety, or when defined threshold conditions are met
STCW Section A-VIII/2 requires the OOW to notify the master in any situation of doubt and whenever specific conditions defined in standing orders are met.
Question 4: What is the function of the 'safe water mark' buoy in the IALA buoyage system?
- Marks the centerline of a fairway or safe passage to both sides (Correct answer)
- Marks a danger with navigable water on the north side
- Indicates the limit of port jurisdiction
- Marks an area of prohibited anchoring
Correct answer: Marks the centerline of a fairway or safe passage to both sides
Safe water marks (red and white vertical stripes) indicate that there is navigable water all around and are used for midchannel or fairway markings.
Question 5: Under STCW, what is the minimum watch alarm (dead man alarm) reset interval for a solo OOW on the bridge?
- Every 6 minutes
- Every 12 minutes (Correct answer)
- Every 15 minutes
- Every 30 minutes
Correct answer: Every 12 minutes
SOLAS and STCW requirements specify that the bridge watch alarm must be reset at intervals not exceeding 12 minutes to confirm the OOW is alert.
Question 6: Which radar presentation mode is generally preferred for collision avoidance watchkeeping?
- Relative motion, ship's head up
- True motion, north up (Correct answer)
- Relative motion, north up
- Course up, stabilized
Correct answer: True motion, north up
True motion, north up presentation gives an accurate picture of the actual movements of all vessels, making collision avoidance assessment more intuitive.
Question 7: What is the difference between a 'course to steer' and a 'course made good' in navigation?
- They are synonymous terms used interchangeably
- Course to steer is the compass heading accounting for leeway/current; course made good is the actual track over ground (Correct answer)
- Course made good is the magnetic course; course to steer is the true course
- Course to steer is the planned route; course made good is the GPS heading
Correct answer: Course to steer is the compass heading accounting for leeway/current; course made good is the actual track over ground
Course to steer compensates for current and leeway, while course made good is the resultant actual direction traveled over the ground.
STCW Navigation & Watchkeeping Practices 4
What does ARPA stand for and what is its primary watchkeeping function?