What is the purpose of a DR plot?

• A. To estimate a ship's position between fixes
• B. To measure weather patterns
• C. To track crew schedules
• D. To determine cargo weight

Answer: (A)

The main idea is dead reckoning navigation. A DR plot is used to estimate where a ship is between known positions by advancing the last fix along the direction you’re steering at the speed you’re actually moving, for the time that has elapsed. In practice, you take the last known position, apply the course over ground and speed over ground for the elapsed time, and plot that projected position. This helps you maintain a working position on the chart when you don’t have a fresh fix, and you can compare it with later fixes to see how far drift or error has accumulated. Context: currents, wind, and leeway can be considered to refine the projection, but the plot’s purpose remains to show the estimated position between fixes. The other options don’t fit because measuring weather, tracking crew schedules, or determining cargo weight are not about estimating or plotting navigational position.