As OOW, your vessel experiences a total loss of GNSS signal approaching a coastline with moderate traffic. What is your immediate response?

A. Continue on the last known GPS-derived course and speed without further action, since the loss is likely temporary

B. Immediately revert to alternative position-fixing methods — radar ranges/bearings to charted features, visual bearings/transits if available, and dead reckoning from the last reliable fix — increase the frequency of position checks, inform the Master, and reduce speed if the situation and available sea room warrant it while confidence in position is reduced

C. Wait for the GPS to restore itself before taking any further navigational action

D. Rely solely on AIS-derived position data from nearby vessels instead

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

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

C. 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

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