What is the magnetic course from Tomlinson Airport (area 1) to Jamestown Airport (area 4)?

• A. 120°
• B. 153°
• C. 183°
• D. 199°

Answer: (B)

Magnetic course is the direction to fly relative to magnetic north, so you determine it by converting the true course shown on the chart using the local magnetic variation for the area. First find the true course between Tomlinson and Jamestown on the chart, then apply the variation to translate that line into a magnetic direction. The rule to use is: east variation subtracts from the true course, west variation adds to it (east is least, west is best). After applying the local variation, the magnetic course you would set for that route comes out to 153 degrees. Wind affects the airplane’s heading needed to stay on that track, not the magnetic course itself.