You're the OOW on a passage through a narrow strait. Your ECDIS shows only small-scale chart coverage for part of the route — the detailed large-scale cells weren't loaded during voyage planning. What should you do?

A. Continue on the planned track — the small-scale chart still shows the general route and main hazards

B. Stop and obtain the correct large-scale chart cells before proceeding, or if already underway, reduce speed, increase fixing frequency using all other available means (radar, visual, soundings), and inform the Master immediately

C. Switch to a paper chart only for the remainder of the passage and disregard ECDIS entirely

D. Continue as planned but make a logbook entry noting the chart gap for the next watch

A. The tidal height at the time of transit to confirm sufficient under-keel clearance

B. The yacht's fuel consumption for that leg

C. The colour of the seabed shown on the chart

D. Only the distance to the next waypoint

A. Assess the situation against the planned route and charted depths, take action to maintain safe water, and inform the Master if there is any doubt

B. Ignore it — ECDIS alarms are frequently false and can be left running

C. Switch the ECDIS to standby mode and navigate by GPS position alone

D. Acknowledge and silence the alarm immediately so it does not distract the helmsman