Simrad AP25, Manual

Page: 49 / 172

Operation
20221495F
47
Operating in WIND
NAV
mode
Refer to Figure 2-2 with references [ ] the associated displays
and the criteria (bullets) below.
•
The set wind angle should be larger than the ‘Minimum
wind angle’ set in the Installation/Dockside menu and
smaller than 170° Apparent.
•
Information about when it is time to head directly towards
the waypoint, Distance To Turn (DTT) and Estimated Time
to Turn (ETT) are displayed. These calculations are based
on the assumption that the set wind angle will be the same or
larger after a tack or gybe towards the waypoint [3] [7].
•
A turn prompt will appear when it is time to head towards
the waypoint and the autopilot will calculate and display the
change of heading by comparing the current heading and the
heading towards the waypoint (CHG) [5].
•
When heading towards the waypoint, the autopilot utilizes
either the XTE from the GPS/Chartplotter to maintain track
or a layline calculated by the autopilot. The calculated
layline applies when the Cross Track Error (XTE) from the
external navigator is larger than 0.15 nm [8].
RACING
If ‘Wind setup’ is set to ‘ RACING ’ in the Installation/Dockside
menu, a more advanced steering is possible:
•
Optimising VMG to wind may be enabled when beating
and it is not possible to head directly towards the waypoint
[2] [4].
•
Layline steering may be disabled when heading directly
towards the waypoint. Instead you can optimise the
Waypoint Closure Velocity (WCV) by trimming the sails
and the set wind angle. A turn prompt will then be
displayed if the difference between Course Over Ground
(COG) and Bearing Position Waypoint (BPW) exceeds 30°
when heading towards a waypoint [8].
See chapter 2.25 Quick Setup on how to access these parameters