I believe they may incorporate their own data in places, which is why I keep Navionics around in addition to "official" ENCs, but I haven't paid much attention to the update frequency. In contrast, with the ENCs there are generally a few updates to be applied every week and thankfully that's just the click of a button away. Such updates often have more to do with lights and buoys; survey dates can be rather ancient.Garmin update their charts at least twice a year, as do Navionics (owned by Garmin now), most other electronic chart producers will do the same or similar i suspect. But, they can only update using the latest survey data, which they take from the likes of the UKHO and other official bodies around the World.
When a student on a MN electronic navigation aids course the instructors used to make the point that the "real world" is outside the wheelhouse (or for many of us the cockpit). The point being that GPS, Chart Plotters, Charts, RADAR, AIS, etc. etc. are no more than aids to safe navigation and are not infallible.If you need a chart to identify that particular chain ferry rather than using No1 eyball then I wonder about was one keeping a good lookout with situational awareness whilst sailing.
I think I've said it before, but the first tool for any navigation is your eyes. And I made maps for a living! But no map or chart is ever 100% up to date, or 100% correct! Using your eyes also has the advantage that things like datum shifts don't affect them.If you need a chart to identify that particular chain ferry rather than using No1 eyball then I wonder about was one keeping a good lookout with situational awareness whilst sailing.
Bit like modern day weather forecasting. If you look out the window instead of at the computer model you might see what is really happening!When a student on a MN electronic navigation aids course the instructors used to make the point that the "real world" is outside the wheelhouse (or for many of us the cockpit). The point being that GPS, Chart Plotters, Charts, RADAR, AIS, etc. etc. are no more than aids to safe navigation and are not infallible.
One of the risks with vector charts. Would be better if a certain level of detail was always present for a given zoom. Bit like a raster chart.
I have got used to Torpoint ferry but mildly alarmed when running nicely downwind in F5 and saw the third supposedly parked ferry start away as we approached to pass astern of 1 & 2. Let navigator start engine but held nerve and remain sail pureDon't forget the three chain ferries at Torpoint. That appear to leave at random times just to snag any passing yacht.
Love there Restricted in Ability to Manoeuvre signs and lights even though they do head off to Falmouth from time to time for servicing.
