Definition
A handheld navigation tool used in flight planning, combining a straightedge with a protractor scale and one or more distance scales matched to common aeronautical chart scales (typically sectional and world aeronautical charts). It is used to measure true course between two points on a chart and to measure distance along that course.
Plain English
A clear plastic ruler with a built-in protractor and chart-matched distance markings. You lay it on a paper chart to draw a course line, read the direction of that line in degrees, and measure how far it is from one point to another.
Context Anchor
Seen during preflight planning when drawing or checking a route on a paper or electronic flight chart.
Derivation
From 'plot,' meaning to mark or trace a course on a chart. A plotter is simply the tool you plot with. The word comes from the same nautical tradition where navigators 'plotted' a ship's course on a sea chart.
Why Pilots Care
Provides accurate measurements needed for dead reckoning, fuel planning, and compliance with navigation requirements.
Analogy
A plotter is like a ruler and angle-measuring tool made specifically for aviation charts.
Intuition Check
A plotter is not a printer or just someone making a plan. In flight planning, it is the tool used to measure course and distance on a chart.
Example Sentence 1
Before the cross-country, the student used a plotter to measure the true course from the departure airport to the first checkpoint.
Example Sentence 2
Using the plotter's distance scale on the sectional chart, she calculated the leg would take 42 nautical miles.