[CA] [CA11] Missing heading vector

[Chuck - Raymarine - Moderator]

danderer,

All vectors are dependent upon having a GPS position FIX from which the vectors will extend. The COG Vector is calculated from Course Over Ground (COG) and Speed Over Ground Data (SOG) data received from the system's GPS data source. The Heading Vector is calculated from Heading (Heading) and Speed Through Water (Speed) data. Heading is typically provided to the system by an autopilot, instrument compass, GPS compass, or gyrocompass. Speed Through Water (Speed) data is typically provided to the system via a transducer (instrument or fishfinder) featuring an operational paddle wheel or via an ultrasonic speed through water instrument transducer. When one commands the system to create vectors of infinite length, Speed Over Ground (SOG) and Speed Though Water (Speed), if any, are replaced within the vector calculations by infinite SOG and speed values. Hence, it is possible for a system which has not been fitted with a Speed Through Water (Speed) sensor to display a Heading vector of infinite length.

One may determine whether the system is fitted with Heading and Speed Through Water sensors by simply configuring the Chart application to display the HEADING and SPEED data items as Data Overlays. Should either of these data items report a value which is dashed, then no operational sensor responsible for that data item has been fitted to the system.