Marking up the chart before flight

Mark five things before flight:

1. Track line: draw first. Dark, neat, distinct from every other line. Highlighter ok if it does not obscure detail.
2. Drift lines: 10 degrees each side of required track, from both ends of each leg. Extend about two-thirds of leg length. Distinct from track line, e.g. dashed.
3. Ten-mile marks: small stroke across track line every 10 miles. Progress check at a glance.
4. Fractional distance marks: split each leg at 1/4, 1/2, 3/4 points. Revise ETA fast, no flight computer.
5. Check points: distinct landmarks every 10 to 15 minutes along track. Mark with arrows or circles. Do not obscure map detail. Very short leg: use only markings that help.

Trap: ten-mile marks are distance based (progress); check points are time based (landmarks). Drift lines stop at two-thirds leg length, not full leg.

Practice