🔍 Key Concepts

• Dead reckoning plotting rules: when must a DR position be plotted? (course change, speed change, fixes, and at least every hour) • Running fix: identify at which labeled point the running fix occurs and note its time window (1030–1100) • Time and label comparison: compare the time of the running fix with the time at "D" and note what has (and has not) changed between C, D, and E

💭 Think About

• Look carefully at what happens at each labeled point: where does course change, where does speed change, and where is the running fix actually taken? • How many minutes after the running fix is point D, and has the vessel changed speed yet by that time? • Which standard DR-plotting rule (course change, speed change, or ‘within 30 minutes of a running fix’) best matches the situation shown at D?

✅ Before You Answer

• Verify from the track line and annotations whether speed actually changes at 1125 or at a different time. • Confirm which labeled point is the running fix (intersection of DR track and the shifted LOP from the tower). • Check whether point D lies within 30 minutes after the running fix time and whether a course change occurred before reaching D.