User manual

XCSoar User Manual
the shaded area. This scaling and arrow makes it easy to see how
the pilot’s MacCready setting compares with achieved thermals
and to plan the desired working height band.
When cruising between thermals, the vertical position of the ar-
row, indicating the glider’s height relative to the thermal band, can
be used as a reference to suggest how urgent it is to find the next
thermal. As the arrow approaches the bottom of the band, then the
glider is nearing the break-off height and the pilot should consider
taking even a weak thermal.
6.7 Thermal locator
An algorithm estimates the center of the lift when circling. The
thermal marker symbol is a green circle with a ‘T’ in the center.
From the configuration menu (Setup System), Display Page, the
option ‘Lift center’ determines how this is used:
OFF : Lift center locator disabled.
Circle at center : A thermal marker is displayed at the center of lift.
Pan to center : A marker is displayed at the center of lift, and when circling,
the display is panned to this lift center.
When the thermal locator is enabled, the location of the last 20
thermals is marked on the map with the thermal marker during
cruise.
This location is calculated to compensate for the thermal drift at
the glider’s height. This means that internally XCSoar remembers
the location of the thermal source on the ground. In other words,
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