Heading alignment
For systems with a compass providing heading data, it is important to ensure correct heading alignment.
Checking alignment
Correct alignment ensures that the heading data provided by the compass matches the actual heading of the vessel. You should check the heading alignment for any new installation.
RadarHeading alignmentChartHeading alignmentOpen the Chart application on the MFD and enable the Radar layer: .
While the vessel is stationary (e.g. tied to a dock), orient the vessel's bow to a known bearing. Examples include:
navigational range markers;
a correctly calibrated fluid-filled compass onboard the vessel;
other fixed marks from which an accurate heading can be obtained.
Alternatively, another option for checking heading alignment is to align the compass to the Course Over Ground (COG) data provided by a GPS receiver, while your vessel is underway in calm conditions where there is no tide.
Use the Radar and Chart displays to confirm the heading alignment. The on-screen icon representing your vessel should be oriented in exactly the same direction as the known bearing (e.g. navigational range marker).
Adjusting alignment
If the heading alignment is incorrect it may be necessary to re-calibrate the compass.
It is also possible that the compass is affected by sources of magnetic interference (such as marine pontoons, high current carrying cables, or electric motors). In this case it will be necessary to re-linearize the compass to compensate for magnetic interference. In extreme cases it may be necessary to re-locate the compass away from sources of magnetic interference.
For instructions on how to re-calibrate and/or re-linearize the compass, consult the compass manual.