ASA Electronics E6-B - Manual (Page 30)

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that represents the true airspeed. Read ground
speed under the grommet. The wind correction
angle is measured right or left of the center line. Be
sure to count the degrees accurately — the value of
each line changes at the 100, 150, or 250 knot arc,
depending on the E6-B model you are using (
see
Note below Figure 21).
Example: You have laid out a course on a
sectional chart and measured it to be 090° true
using your plotter. The winds aloft forecast
calls for the wind at your chosen altitude to be
230° at 18 knots, and the performance data for
the airplane says that you can expect a true
airspeed of 125 knots at that altitude.
1. Set 230° at the TRUE INDEX.
2. Using any convenient starting point, mea-
sure 18 units up from the grommet toward the
TRUE INDEX and make a dot at 18 units (
see
Figure 22).
3. Rotate the transparent disk to bring 090° to
the TRUE INDEX.
4. Move the slide until the wind dot falls on the
arc for 125 knots ( see Figure 23 on Page 32).
5. Read the ground speed of 138 knots under
the grommet; the fact that the wind dot is
below the grommet indicates a tailwind.
6. The wind dot is 5° to the right, indicating that
the true heading should be 095°. Now all you
have to do is apply local magnetic variation to
derive magnetic heading.
If the upper winds forecast applies to your entire trip,
simply use the wind dot in this manner with the true
course for each leg.