FOLLOW A ROUTE ON YOUR PLOTTER

Having completed your plotter set-up (MBY Oct) and planned and entered your route (MBY Nov), now comes the part that all that preparation was for – actually running the route.

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In theory, if the first two steps have been completed correctly, this should be a simple case of just following the pre-programmed information. However, as a navigation examiner of many years, I can honestly say I have seen many skippers struggle to interpret and check the information in front of them, even when they have actually planned it all correctly.

There are a number of things to be wary of but these are the ones that occur most often:

Waypoint arrival alarms – most systems allow you to adjust the range so that it activates at a sensible range of, say, 100m. If it’s set too wide, ie 500m, it will say you are at the waypoint when in reality you still have quite a way to go. This can have serious implications, as it may not be safe to switch headings to the next waypoint until you are much closer to or even just past your chosen waypoint. Change heading too early and it may take you somewhere unsafe.

On a similar note, once the alarm has triggered, most systems switch to the next waypoint as soon as you press ‘acknowledge’. If your waypoints are set close together, that might simply cause it to trigger again immediately for the second waypoint. So particularly in a congested area, like our planned route, it’s important to have a tightly defined waypoint arrival alarm, and then make sure you are completely happy with your location before changing heading. There is no problem with switching to the next waypoint early using waypoint advance if you are sure that you have completed all your checks.