Know the navigation tools you use!
Three weeks ago.
Things are a bit intense here aboard Manami II. We are about 100-150 Nm WSW off the Portuguese SW corner. It is very early in the morning hours... The sky is dark grey, half lit,... but we don't know if the faint light comes from the moon or if the sun is actually raising at dawn. And the wind is absolutely ***howling*** in the rigging, at 30-35 kts. We are wet, we are cold, we are tired, and we're in the deep end of a low pressure area, sailing South.
But this time, we came from the UK, hugging the Spain and Portugal West coast, to cut across to the Canaries.
Apparently.......... there are two shallow areas (20-25m depth) underwater mountains raising steeply from 1000-2000m depth to +-20m, in the middle of the ocean in the area we were about to cross (picture below - iSailor screenshot).
It took me by surprise as normally, when I come in from Gibraltar we don't venture that far offshore, west. But the real surprise was that the (expensive, annual renewable) Navionics charts we have on our tablets/phones/chart plotter,... did NOT show any details of these shallows, unless if fully zoomed in. Reminds me of Vestas/11th Hour crash onto a non-zoomed-in reef off Madagascar, in the Volvo Ocean race some years ago, right?
And even when fully zoomed in, those Navionics charts did not show any details at all. (see pic below of a Navionics screen shot - no details of the depths, and no details there were actually two underwater peaks - compare to the below iSailor screen shots)
Meanwhile, my mickey-mouse cheap (and no longer supported/updated) iSailor maps on my Iphone, clearly showed the shallows, even when zoomed fully out.
WTF Navionics/Garmin?!?! Like, really, WTF?!?
I mean.. we came across those shallows in 35 kts wind in the dark. There must have been significant weird currents and standing waves, if we were to have gone over these shallows.
Navionics, hey..!? A cheap no-longer supported app like iSailor with outdated charts, payable “once and good for life”, outranks an app like Navionics in details?! A bit scary, knowing Navionics is used and dearly paid for - thru annual expensive subscriptions - by many cruisers?!
Lessons learned: Electronic charts are fine, but know the limitations of the tool. And compare different tools. I am sticking to iSailor which saved my *ss so many times in the past. Even if the tool is no longer supported, and charts have not been updated for a while.
And by the way, over the years, I had too many instances of navigation bouys marked in Navionics, but which nowhere to be spotted in “real life”. That means, as a full-time sailor, I would never rely on this over-priced, faulty piece of crap software, as my sole navigation aid.
*end of rant*
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