The reliability of C-Map electronic charts in the Arctic
by Jimmy Cornell on 6 Nov 2014
How are we going to get out of here? Cornell Sailing Events
During this summer I completed a 8500-miles voyage in the North Atlantic that took me from London, UK, to Annapolis, USA, via Greenland and Arctic Canada. Throughout this voyage I used exclusively C-map electronic charts produced by Jeppesen. I found their accuracy to be quite remarkable wherever we sailed, not just in such well-charted areas as the waters of the UK or USA, but even in the remote Arctic areas of Greenland and Canada.
Two examples of the usefulness of the tracks being shown on the B&G chart plotter proved very helpful on two separate incidences in the Arctic.
Having been beset by ice in Lancaster Sound, at the eastern end of the Northwest Passage, we had to physically push our way out by finding narrow leads through the large ice floes.
More often than not the leads would point away from the direction we wanted to go, which was where we believed the open sea to be.
After a while we became totally confused as to our actual location. Several times we passed an ice floe marked by our distinctive green anti-fouling paint, which showed that we had passed through there before. It only then occurred to me to look at the record of previous manoeuvres and thus managed to escape the grip of the ice after being held captive for 14 hours and reach the open sea.
We greatly benefitted from being able to monitor our movements on the electronic charts during a violent storm in Dundas Harbour. Although we were well anchored and our heavy Rocna anchor and 90 m of chain were obviously holding us in place, there was another yacht close to us that was swerving dangerously towards us during the stronger gusts.
I therefore decided to start the engine and move slowly forward, thus pointing into the wind. In this way we managed keep at a safe distance from the neighbouring yacht, and also to take the strain off the anchor when we were hit repeatedly by gusts over 50 knots. We survived the storm without any damage, but after 27 hours of this kind of defensive manoeuvring our tracks recorded on the chart plotter had become a solid, almost black shape of intersecting lines that any surrealist artist would probably envy.
After those two incidents I now look forward to continue using C-Map charts in more benign conditions during my forthcoming world voyage as part of the Blue Planet Odyssey round the world Cornell Sailing
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