Garmin GPSMAP 87 Series, Owner'S Manual

Page: 32 / 86

Setting the Distance between the Bow and the GPS
Antenna
You can enter the distance between the bow of your boat and
the location of your GPS antenna. This helps ensure the bow of
your boat crosses the starting line at the precise start time.
1
From a navigation chart, select Menu > Sailing > Start Line
> GPS Bow Offset .
2
Enter the distance.
3
Select Done .
Laylines Settings
To use the laylines features, you must connect a wind sensor to
the chartplotter.
When in sailing mode (
Setting the Vessel Type , page 5 ), you
can display laylines on the navigation chart. Laylines can be
very helpful when racing.
From the navigation chart, select Menu > Layers > My Vessel >
Laylines > Setup .
Display : Sets how the laylines and vessel appear on the chart,
and sets the length of the laylines.
Sailing Ang. : Allows you to select how the device calculates
laylines. The Actual option calculates the laylines using the
measured wind angle from the wind sensor. The Manual
option calculates the laylines using manually entered
windward and leeward angles.
Windward Ang. : Allows you to set a layline based on the
windward sailing angle.
Leeward Ang. : Allows you to set a layline based on the leeward
sailing angle.
Tide Correction : Corrects the laylines based on the tide.
Layline Filter : Filters the layline data based on the time interval
entered. For a smoother layline that filters out some of the
changes in the boat's heading or true wind angle, enter a
higher number. For laylines that display a higher sensitivity to
changes in the boat's heading or true wind angle, enter a
lower number.
Setting the Keel Offset
You can enter a keel offset to compensate the water depth
reading for the transducer installation location. This allows you
to view the depth of the water below the keel or the true depth of
the water, depending on your needs.
If you want to know the water depth below the keel or the lowest
point of your boat and the transducer is installed at the water
line or anywhere above the end of the keel, measure the
distance from the transducer location to the keel of the boat.
If you want to know the true water depth and the transducer is
installed below the water line, measure the distance from the
bottom of the transducer up to the water line.
NOTE: This option is only available when you have valid depth
data.
1
Measure the distance:
• If the transducer is installed at the water line or
anywhere above the end of the keel, measure the
distance from the transducer location to the keel of the
boat. Enter this value as a positive number.
• If the transducer is installed at the bottom of the keel
and you want to know the true depth of the water,
measure the distance from the transducer to the water
line. Enter this value in as a negative number.
2
Complete an action:
• If the transducer is connected to the chartplotter or a
sonar module, select Settings > My Vessel > Depth and
Anchoring > Keel Offset .
• If the transducer is connected to the NMEA 2000 network,
select Settings > Communications > NMEA 2000 Setup
> Device List , select the transducer, and select Review >
Keel Offset .
3 Select if the transducer is installed at the water line, or
select if the transducer is installed at the bottom of the
keel.
4
Enter the distance measured in step 1.
Sailboat Autopilot Operation
CAUTION
When engaged, the autopilot controls only the rudder. You and
your crew remain responsible for the sails while the autopilot is
engaged.
In addition to heading hold, you can use the autopilot to maintain
a wind hold. You can also use the autopilot to control the rudder
while tacking and gybing.
Wind Hold
You can set the autopilot to maintain a specific bearing relative
to the current wind angle. Your device must be connected to a
NMEA 2000 or NMEA 0183 compatible wind sensor to perform
a wind hold or a wind-based tack or gybe.
Setting the Wind Hold Type
Before you can enable the wind hold type, you must connect a
NMEA 2000 or NMEA 0183 wind sensor to the autopilot.
For advanced autopilot configuration, see the installation
instructions included with your autopilot.
1
From the autopilot screen, select Menu > Autopilot Setup >
Wind Hold Type .
2
Select Apparent or True .
Engaging Wind Hold
Before you can enable the wind hold type, you must connect a
NMEA 2000 or NMEA 0183 wind sensor to the autopilot.
24 Sailing Features