Autopilot No Drift mode practice

Heading hold and a ground-track mode — definition answer different steering requests. A useful No Drift — definition practice session compares the vessel’s heading with its movement over the ground, then checks the exact system’s behaviour. Do not treat No Drift, Track and route-following modes as interchangeable names or choose one as a universal coastal default.

Before relying on any ground-track feature, ask what information it uses and what happens when that information is unavailable. Read the manual for the exact system rather than transferring the name or behaviour from another brand. Demonstrate the mode in suitable clear water and compare the vessel’s position with the intended track. Accuracy does not make a track safe: the route still needs review and the lookout remains with the watch. After an avoidance manoeuvre, reconsider the rejoining turn before asking the pilot to return to its previous line.

Before the demonstration, use the equipment manual to identify what the selected mode is intended to hold and which inputs it requires. Ask the instructor to distinguish the heading display from course over ground and any route or cross-track indication.

Choose a suitable area with clear sea room and maintain lookout throughout. Observe the boat’s position as well as the numbers. Record which mode was used, the relevant data sources and how manual control was restored. The exercise is about interpreting the system, not proving that it can overcome every current.

A mode that follows a line may command a correction when engaged from a different position. Review the expected turn before accepting it. Repeat that assessment after an avoidance manoeuvre rather than assuming re-engagement will continue the previous heading.

Discuss the response to missing navigation data using the supported instruction procedure. Do not disconnect equipment underway to create a fault. Note the appropriate fallback and the indications that require manual intervention.