Measuring Distance and Variation

Remember that each leg of your trip should have a separate line on the flight log. For each leg determine the minimum en-route altitude. It should be 1,000 feet above the highest obstacle within the 10° drift lines. You can use the Maximum Elevation Figure (MEF) however this may consider terrain which is not along your route of flight.

Determine the variation from the isogonic line that is closest to the mid-point of the track (not shown).

Now use your ruler to measure the distances of each leg and record it in the flight log. Use of the flight ruler is fairly straightforward, use it just like any other ruler, however, make sure you are using the correct scale. At this point, your flight log should look something like the one shown below.