Sitex SP38 Autopilot, Installation And Operation Manual

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Sitex SP38 Installation and Operation Basic Operation
Document PN 29010101 V2r0
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If there is a large cross-track error, the autopilot may overshoot the intended track. This is a
function of turn rate, vessel speed, and position updates received from the Navigation
System. For best performance, it is always best to minimize any cross-track error before
putting the autopilot into NAV mode.
Figure 51 – Response of Vessel to a Large Cross-Track Error
The total number of degrees that the autopilot will correct the heading received from the
Navigation System as it tries to bring the vessel back on track is limited to the value set for
“XTE Limit” in the Nav menu.
Caution! Be sure to maintain a sharp lookout to ensure that there are no obstacles
between the vessel and the original track.
Correction set to Both – Steering To/Along a Track
In this method shown in
Figure 52
, the SP38 will bring the vessel onto the track as
smoothly and efficiently as possible. It does this by combining aspects of steering, using
cross-track error, bearing from original to destination, and bearing directly to the
waypoint.