45
p
Example:
SIGMA 7 28
Example: The fi rst SPI position applies to 13,5 km/h head
wind or a sink rate of 1,7 m/s or an expected climb of 0,6 m/s
(see I in the illustration).
If you want to take into account a combination of headwind, descen-
ding air and expected climb you have to choose a somewhat non-li-
near addition of your accelerate increments (because the polar cur-
ve is not linear).
Example: If the headwind is, say, 13,5 km/h and the sink ra-
te is 1,7 m/s, you have to accelerate somewhat more than
position two on the SPI (see II in the illustration). If you also
expect the next climb to be 0,6 m/s you should choose quite
a bit more speed than position three. (see III in the
illustration).
To get a better idea of the polar curve and how it affects this extra-
addition when combining the factors you can try out the SIGMA 7
simulator in various fl ying situations at www.advance.ch.
08290300_Advance_HB_SIGMA7.indd 45
08290300_Advance_HB_SIGMA7.indd 45
04.06.2008 14:27:48 Uhr
04.06.2008 14:27:48 Uhr