User manual

XCSoar User Manual
Zero range yields a nominal task distance: for sectors the target is
half way along the bisector radial; for cylinders the target is in the
center of the cylinder.
The targets can be modified in two ways:
• From the task calculator dialog (see Section 4.8), the Range
field adjusts the targets of all remaining waypoints in the
task.
• From the task editor dialog (see Section 4.4), the range of
each waypoint may be individually adjusted.
When flying an AAT task, the navigation system directs the glider
to the target, and statistics like distance to waypoint are also rela-
tive to the target rather than the waypoint of the AAT area itself.
Automatic task waypoint advancement normally triggers when en-
tering an AAT area, so if the pilot wishes to fly to the targets, either
the ‘arm start’, ‘arm’ or ‘manual’ advancement modes should be
used when flying AAT tasks. See Section 4.5 for details.
The typical use of targets in flying AAT is as follows:
• Set the expected MacCready, bugs/ballast and wind settings
for the flight using the basic settings and wind settings di-
alogs.
• Define the task as normal from the task editor.
• Based on the pilot’s judgement of how good the weather
is, and whether some areas are likely to me more or less
difficult than others, targets may be set individually for each
turn-point in the task editor. The ETE field in the task editor
can be compared to the assigned minimum time to check the
planned task is efficient and long enough.
• During flight, if situations change, such as changed Mac-
Cready setting or wind, the task calculator can be brought
up to show the estimated task time, again allowing compar-
ison to the assigned minimum time.
• If the pilot decides to extend or shorten the flight, all the
remaining targets can be modified from the task calculator.
The task calculator therefore allows the pilot to make (and help to
answer) ‘what if?’ questions, for example:
• What will happen if the conditions improve? The Mac-
Cready setting can be increased and the pilot can see if there
is sufficient adjustment to targets in order to be able to ex-
tend the planned task.
61