User manual

5 Glide Computer
This chapter focuses on how XCSoar’s glide computer works and
is recommended reading so you understand the specific details of
calculations being performed and how to use the software prop-
erly. It assumes a basic knowledge of cross-country soaring, but is
suitable reading for competition pilots as well as pilots engaging
in casual cross-country touring.
5.1 Flight modes
XCSoar automatically detects the difference between thermal (cir-
cling) flight and cruising flight. After about 30 seconds of circling
flight the software will switch from cruise to climb mode. After
about 30 seconds of straight line flight the software will switch
from climb to cruise mode.
The cruise modes are further divided into final glide and normal
cruise. Final glide is active when the last waypoint in the task is
active, or when the task is in abort mode.
Cruise : The glider is not circling and there is either no task active,
or the task waypoint is not the finish point.
Circling : The glider is circling (though it may not be climbing).
Final glide : The glider is not circling and the active waypoint is the final
one in the task.
The specific computations performed by XCSoar are of course de-
pendent on this flight mode. The display changes in each mode,
principally, the InfoBoxes may be set up differently for each mode;
secondly there is a facility to automatically change zoom between
circling and other flight modes (this is called ‘circling zoom’).
Switching between the different flight modes is automatic. Cir-
cling is enabled when the glider turns (typically three quarters of
a turn). It is possible to have circling mode switched based on an
external input (e.g. from a pilot-operated switch).
A small symbol is drawn on the lower right corner of the map area
to indicate which flight mode the computer is in.
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