Furuno NAVpilot-300 Operator's Manual page 33

Spiral turn
Own Ship
indication
Turn radius
(see section 2.5.3)
If the spiral turn is initiated from NAV mode, the waypoint/destination name appears
on the spiral turn screen with the "NAV" icon indicating where the turn was initiated
from.
The boat spirals in the direction of current heading (STBY), set course (AUTO) or the
course to the next waypoint (NAV) that was active at the moment that the spiral turn
is started. The spiral speed can be set in the menu. The arrival alarm must also be
active on the chart plotter.
The boat will continue to spiral until the AUTO or STBY key is pressed.
Note: If the boat does not enter the arrival alarm area, the NAVpilot does not switch
to the next waypoint. To prevent this, set the arrival alarm range as large as possible
and activate the perpendicular function on the chart plotter.
COG
COG
Radius (set on menu)
Distance between spiral centers (D)
D (NM) = 6.28 × Spiral Radius
Spiral Speed
2. STEERING MODES
Speed at which
spiral center-point
moves
(see section 2.5.3)
Waypoint name
NAV icon
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