Ship Heading ; Attitude Reference

Why ships need a true-north heading source, not a magnetic compass

Magnetic variation makes magnetic heading unreliable on long north-south routes; steel hulls, deck cranes and container stacks make it worse. GNSS course-over-ground is not heading at all when the ship is drifting in current or manoeuvring slowly. The GMF305 detects the Earth's own rotation rate to determine true north directly — no magnetic field, no satellite signal, no motion required. Once aligned it holds heading at 0.5°/h while continuously reporting roll and pitch to 0.1°, giving the bridge and automation systems a single, trustworthy attitude reference.

Typical use cases

One box, four marine jobs

Bridge navigation & gyrocompass backup — the GMF305 mounted in the bridge gyro room delivers true heading to ECDIS, radars and autopilot, independent of magnetic variation.
Dynamic positioning (DP) heading reference — stable 0.5°/h heading hold lets DP computers command bow and stern thrusters against wind and current without heading drift.
Cargo crane boom stabilization — roll and pitch output at 0.1° feeds active heave-compensation and boom-levelling controllers during container or offshore lifts.
Offshore loading & mooring orientation — true-north heading and attitude support FPSO offloading, single-point mooring and cable-lay heading control.