User manual

XCSoar User Manual
If Vega or an intelligent variometer is connected with Netto output,
the Netto vario value is used; hence the colours and thickness of
the trail indicates the air-mass vertical movement rather than the
glider’s vertical movement.
The snail trail display can be toggled between off, a short trail
(about ten minutes) or a long trail (about one hour). This can be
performed permanently through the configuration settings or tem-
porarily by the menu:
DISPLAY . Snail trail
In order to assist centering thermals in the presence of wind, the
snail trail can be artificially drifted with the wind as it is displayed.
In this way, the snail trail is referenced to the prevailing wind
rather than referenced to the ground. Since thermals drift with
the wind also, the drifted trails give a better indication of where
the glider has been relative to the thermals.
An example of this is illustrated below. Note that when trail drift is
active (right picture), the glider appears to be circling in a column
rather than an elongated spiral (left picture).
Enabling trail drift is performed through the configuration settings.
The compensation is only performed whilst in circling mode; the
display of the trail in cruise mode is unaffected. This can also be
performed from the wind settings dialog:
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