Q: You hold an OOW < 500 GT Near-Coastal certificate. Your examiner asks you to describe what this certificate permits you to do and what it does NOT allow.

STCW Regulation II/3 OOW Near-Coastal certificate permits: watchkeeping officer duties on ships of less than 500 GT engaged on near-coastal voyages only. Near-coastal: defined by the flag state — in the UK (MCA), near-coastal means voyages within the sea area defined in Merchant Shipping Notice MSN 1861 (MCA-defined near-coastal waters including UK coastal waters, and areas agreed with specific flag states). Limitations: (1) The certificate is NOT valid for unlimited oceans voyages; (2) NOT valid on ships 500 GT or above; (3) The holder cannot act as OOW on international voyages beyond the near-coastal limit without holding STCW II/1 (OOW Unlimited); (4) Near-coastal OOW in STCW covers the STCW II/3 competencies which are the same functional areas as II/1 but assessed at the operational level appropriate to near-coastal operations and vessels under 500 GT. STCW Chapter II Regulation II/3 establishes the mandatory minimum requirements for OOW on ships of less than 500 GT. The near-coastal restriction is defined by each flag state — the MCA defines UK near-coastal as specified in MSN 1861 and related Merchant Shipping Notices. The competency framework for II/3 covers the same seven functions as II/1 (Navigation, Cargo, Stability, Machinery, Electrical, Maintenance, Watchkeeping) but at a level appropriate to smaller vessels on near-coastal voyages. A candidate must be aware: the MCA sometimes accepts STCW II/3 alongside practical endorsements for certain vessel types (fishing, passenger ferries, workboats). The OOW NC holder who works on a 300 GT coastal ferry in UK waters is correctly certificated; the same person who signs as OOW on a 400 GT vessel making a transatlantic passage is operating outside their certificate's geographic scope.

Question 1

You are planning a coastal passage in a 150 GT fishing support vessel. The chart shows a depth of 3.2m at a certain point. The tide tables show a positive tidal height of +1.8m at the time of your passage. Your vessel's draft is 3.5m. Can you pass safely?

Accepted Answer

Chart depth analysis: chart depths are referenced to Chart Datum (CD) = Lowest Astronomical Tide (LAT) — the lowest predicted tide level. The tidal height of +1.8m above chart datum means the actual depth at the time of passage = charted depth + tidal height = 3.2 + 1.8 = 5.0m. Your vessel's draft is 3.5m, so available UKC = 5.0 − 3.5 = 1.5m. Whether this is adequate depends on your company UKC policy (typically minimum 0.5-1.0m for coastal vessels, with allowance for swell, squat, and chart accuracy). At 1.5m UKC with a 3.5m draft vessel in calm coastal waters with accurate charts, passage is marginally feasible but requires verification of: swell state, vessel's speed (squat), and chart survey reliability for that area. Chart datum and tidal height calculations are core near-coastal navigation knowledge. The key principle: Chart Datum = LAT (Lowest Astronomical Tide). Charted depths show the depth AT LAT — the minimum water that will normally exist at that point. When the tide rises above LAT (which it almost always is), water is ADDED to the charted depth. When the tide falls below LAT (theoretically possible in some tidal conditions — negative tidal heights do exist), water is SUBTRACTED. Formula: Actual Depth = Charted Depth + Tidal Height (positive adds; rare negative values subtract). UKC = Actual Depth − Ship's Draft. Additional considerations for UKC: (a) squat at speed; (b) rolling in a swell (dynamic draft increase); (c) chart accuracy in survey area; (d) chart datum variations — in some areas CD differs from LAT slightly. The MCA MGN 315 (Keeping a Safe Navigational Watch on Merchant Vessels) and related notices specify UKC minima for UK coastal waters. At OOW NC level, this calculation is expected to be done mentally or quickly — it is a common exam question precisely because it catches candidates who get the sign convention wrong.

Question 2

You hold an OOW < 500 GT Near-Coastal certificate. Your examiner asks you to describe what this certificate permits you to do and what it does NOT allow.

Accepted Answer

STCW Regulation II/3 OOW Near-Coastal certificate permits: watchkeeping officer duties on ships of less than 500 GT engaged on near-coastal voyages only. Near-coastal: defined by the flag state — in the UK (MCA), near-coastal means voyages within the sea area defined in Merchant Shipping Notice MSN 1861 (MCA-defined near-coastal waters including UK coastal waters, and areas agreed with specific flag states). Limitations: (1) The certificate is NOT valid for unlimited oceans voyages; (2) NOT valid on ships 500 GT or above; (3) The holder cannot act as OOW on international voyages beyond the near-coastal limit without holding STCW II/1 (OOW Unlimited); (4) Near-coastal OOW in STCW covers the STCW II/3 competencies which are the same functional areas as II/1 but assessed at the operational level appropriate to near-coastal operations and vessels under 500 GT. STCW Chapter II Regulation II/3 establishes the mandatory minimum requirements for OOW on ships of less than 500 GT. The near-coastal restriction is defined by each flag state — the MCA defines UK near-coastal as specified in MSN 1861 and related Merchant Shipping Notices. The competency framework for II/3 covers the same seven functions as II/1 (Navigation, Cargo, Stability, Machinery, Electrical, Maintenance, Watchkeeping) but at a level appropriate to smaller vessels on near-coastal voyages. A candidate must be aware: the MCA sometimes accepts STCW II/3 alongside practical endorsements for certain vessel types (fishing, passenger ferries, workboats). The OOW NC holder who works on a 300 GT coastal ferry in UK waters is correctly certificated; the same person who signs as OOW on a 400 GT vessel making a transatlantic passage is operating outside their certificate's geographic scope.

Question 3

You are OOW on a 280 GT passenger ferry making a coastal passage through an area with strong tidal streams of up to 3.5 knots. Your vessel's speed is 9 knots. Explain how you plan for the tidal stream effect.

Accepted Answer

Tidal stream planning: (1) Extract tidal stream data from the relevant tidal stream atlas or chart tables — timing referenced to HW at the nearest standard port; (2) Calculate the tidal stream vectors for each hour of the passage (direction and rate vary through the tidal cycle); (3) Vector triangle method: plot course to steer (CTS) to achieve the desired track made good — add own ship speed vector and tidal vector to calculate the heading required to maintain the track; (4) At 3.5 knots tidal stream vs 9 knots own speed, the cross-tide component at 90° would require approximately 23° of course correction; (5) Calculate ETAs using speed made good along track (not ship speed); (6) Identify timing of fair vs foul tide — plan departure to favour the fair tide for the main channel crossing; (7) Check for minimum depth at tidal gates — arrive at the gate when sufficient water depth exists. Tidal stream planning is a core near-coastal navigation competency. The vector triangle: the navigator must draw (or calculate) three vectors — the water track (direction and speed of the ship through the water), the tidal vector (direction and rate of tidal stream), and the resultant ground track (the actual path made good over the seabed). To maintain a specific ground track, the ship's heading must be adjusted to compensate for the tidal set. The correction formula: if tidal stream is perpendicular to the track at 3.5 knots and own speed is 9 knots, sin(correction angle) = tidal component / own speed = 3.5/9 = 0.389, correction ≈ 23°. At near-coastal OOW level, the examiner expects: (a) knowledge of tidal stream atlases and use of interpolation between hourly vectors; (b) understanding of spring/neap tidal differences; (c) awareness of "tidal gates" — points in the route where passage is only possible at certain states of tide due to depth or current strength. UK examples: Portland Race, Alderney Race, Pentland Firth — areas where strong tidal streams create dangerous conditions for small vessels.