You are on coastal watch and GPS has failed. Your examiner asks you to describe how you would fix the vessel's position using visual methods, and what constitutes a reliable fix.

A. Visual fixing methods: (1) cross-bearings — take simultaneous compass bearings on two or more charted objects; three bearings form a "cocked hat" — the vessel is within the triangle; (2) transit — when two charted objects are in line, the vessel is on that transit bearing; (3) range and bearing — bearing plus distance by radar to a charted object; (4) four-point bearing / doubling the angle on the bow — timed run between two different bow angles to calculate distance off. A reliable fix requires at least three position lines nearly at right angles. The fix should be plotted immediately on the chart and time noted.

B. Without GPS, navigation must stop until GPS is restored. Visual fixing methods are not sufficiently accurate for safe coastal navigation.

C. Two bearings are sufficient for a reliable fix. Three bearings create confusion when they do not meet at a point — use the average of the three.

D. DR (dead reckoning) using the last known GPS position, speed and course is the approved primary method when GPS fails. Visual methods are a secondary check only.

A. SOLAS V Reg 34 requires that before proceeding to sea, the master shall ensure that the intended voyage has been planned using adequate and up-to-date charts and nautical publications. The four stages are: APPRAISAL (gather all relevant information); PLANNING (lay the plan on charts from berth to berth); EXECUTION (monitor progress against the plan); MONITORING (cross-check position continuously throughout the voyage).

B. SOLAS V Reg 34 requires a passage plan only for voyages exceeding 200 nautical miles. For shorter voyages a verbal brief to the OOW is sufficient.

C. SOLAS V Reg 34 requires the Chief Officer to produce the passage plan and present it to the master for signature. The OOW has no planning responsibility.

D. The four stages are: depart, transit, arrive, anchor. SOLAS V Reg 34 specifies that plans must be filed with the port authority before departure.

A. The shoal is a no-go area. You would draw a no-go zone on the chart with a safety margin added for squat, wave response, tidal variation, and chart accuracy. A clearing bearing or limiting danger line would be drawn to keep the vessel safely clear. The passage plan waypoints must route the vessel outside this zone. The abort point where you could no longer safely turn back or divert must also be marked.

B. Check the tide tables — if the tide adds 1m of water at the time of passing, the available depth is 7.5m which exceeds your draft of 7.2m with 0.3m to spare. Mark this as a tidal gate in the plan and proceed.

C. A 6.5m shoal with 7.2m draft has 0.7m of clearance. This is within MCA-approved underkeel clearance limits and no special marking is required.

D. Report the discrepancy to the chart agent as a possible chart error and proceed on the original route pending correction.