Heading
Setup and operation of the heading sensor (heading device).
Heading Sensor Setup
Menu path |
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The sensor connection and setup are performed in accordance with the procedure.
Heading sensors: magnetic compass, gyrocompass, or **INS** (Integrated Navigation System).
Received message processing must be correctly configured in the sensor settings.
Heading devices, depending on the device type, transmit the following IEC 61162 sentence headers:
HC — magnetic compass;
HE — gyrocompass, free in azimuth;
HF — induction magnetic compass;
HN — gyro heading device, gyro azimuth;
GP, GL, GA, GB, GN — satellite compass;
SN — inertial navigation system;
IN — integrated navigation system;
U0…U9 — non-standard header (typically used by non-standard equipment manufacturers). Used rarely.
Recommended Sentence Set for Heading Sensor

The heading device has no additional specific settings.
Error
ECDIS receives the true heading value from the magnetic compass. Application of current magnetic variation and magnetic compass deviation must be performed by the navigator on the main magnetic compass instrument.
Error
ECDIS receives the true heading value from the gyrocompass. Application of the gyrocompass constant correction must be performed by the navigator on the main gyrocompass instrument.
Heading Sensor Operational Features
The vessel heading is displayed in the following interface elements:
Off-scale Danger Indicators (Danger Course Indicator)
Log book in the Standard Position (Track) section

No. |
Field |
Description |
|---|---|---|
1 |
Heading |
Heading received from the heading sensor. Received from sentences: |
HDG |
Navigation parameter name — heading |
|
Gyro_Prim |
Name of the sensor providing the data |
|
2 |
Rate of Turn |
Rate of turn received from the heading sensor, if the sensor generates it. Received from sentences: |
ROT |
Navigation parameter name |
|
Gyro_Prim |
Name of the sensor providing the data |
|
3 |
– |
Visual representation of heading on the heading scale of the off-scale danger indicator. Received from sentences: |
Heading Discrepancy
When two or more heading sensors are connected to ECDIS, the discrepancy between the Primary and Secondary sensors will be calculated.

No. |
Element |
Description |
|---|---|---|
1 |
Primary heading sensor with priority 0 |
|
2 |
Secondary heading sensor with priority 1 |
|
3 |
Discrepancy |
Heading discrepancy between Primary and Secondary heading sensors |
Important
When heading sensor data is absent, the vessel mark on the chart is displayed without heading line indication, and the vessel outline will not be displayed at ENC scale.
When heading data is available, the following tasks are performed:
total drift compensation;
wind calculation;
vessel movement with drift calculation and monitoring band construction;
anchor watch;
vessel outline construction at chart scale;
radar image overlay.
Heading Sensor Warnings
Operating mode messages (rows 2-5 of the table) are generated based on the Mode indicator field value in the THS message.
TEXT |
CATEGORY |
CONDITION |
|---|---|---|
Heading sensor error: <sensor name> |
Warning |
When data from the sensor stops being received according to the configurable timeout. |
Simulation mode: <sensor name> |
Warning |
Mode indicator field has value S — simulation mode. |
Dead reckoning mode: <sensor name> |
Warning |
Mode indicator field has value E — dead reckoning mode. |
Manual heading input: <sensor name> |
Warning |
Mode indicator field has value M — manual input. |
Heading sensor data invalid: <sensor name> |
Warning |
Mode indicator field has value V — data unreliable. |
Magnetic variation unknown: <sensor name> |
Warning |
Unable to obtain or calculate true heading. The HDG message is used for calculations and heading display in the system, but magnetic variation data is absent. |