Avidyne IFD550 Pilot's Manual page 132

IFD500 Series Pilot Guide
Visual approach depiction (left downwind to runway 22)
When flying a visual approach, lateral deviations are provided to
the final approach course. Advisory vertical deviations are also
provided once the aircraft track is at most 90 degrees to the final
approach course. Therefore, on a downwind entry the VDI will
remain flagged until the aircraft completes the turn to base.
Visual approaches are activated exactly like instrument
approaches. However, the LSK legend will show "Activate
Visual" rather than "Activate Approach", providing a further
reminder that a visual approach is in use.
Configuring Visual Approaches
Several user configurable settings are available on the Setup
page to control the appearance and behavior of visual
approaches (see page 5-60). The settings can be used to adjust
for user preferences or aircraft performance.

Pattern width – distance between the runway and a
downwind leg

Final length – distance from the runway threshold at
which a base leg intercepts the final approach course

Glideslope – the descent angle of the final approach
3-42 FMS Subsystem