🔍 Key Concepts

• Estimated position (EP) vs fix – what each means in coastal navigation • How many lines of position (LOPs) are needed for a fix versus an EP • Common sources of uncertainty in position plotting (questionable data, single LOP, dead reckoning)

💭 Think About

• Ask yourself: when your information is incomplete or of doubtful quality, what type of position do you plot on the chart? • Consider whether an estimated position must always use multiple good LOPs, or whether it can be based on weaker information. • Think about what makes a radar fix strong or weak compared with an estimated position – which should normally be considered more reliable?

✅ Before You Answer

• Verify the definition of a fix: how many reliable LOPs and of what quality are usually required. • Check what navigators typically use an EP symbol for on the chart (e.g., dead reckoning advanced to an LOP, single LOP plus DR, etc.). • Be sure you understand that an EP reflects uncertainty, and ask which option best matches that idea while avoiding statements that sound "more accurate than a fix."