Definition
Lines drawn on an aeronautical chart connecting the departure point to the destination (and any intermediate points), representing the intended track of the flight over the ground.
Plain English
The lines you draw on your chart to show the route you plan to fly from where you take off to where you're going.
Context Anchor
Used during cross-country preflight planning when marking a chart and preparing the route of flight.
Derivation
Course' comes from the Latin 'cursus,' meaning a running or path. A 'course line' is literally the drawn path the aircraft is intended to follow.
Why Pilots Care
They let pilots measure distances, compute headings, and plan fuel and time before departure.
Intuition Check
Do not read course lines as lines already printed on the chart. In this context, they are the route lines the pilot draws or plots to show the planned path of flight.
Example Sentence 1
After plotting course lines from the departure airport to each checkpoint, the student measured the true course with a plotter.
Example Sentence 2
Each course line was measured to determine the magnetic heading and estimated time en route.