The Finnish charts contain a statement at the beginning to the effect that only soundings etc. INSIDE the buoyed channels can be relied on. Having hit a rock this summer in the middle of a bay where the least sounding (on the latest Finnish chart) was 4.7m, I can confirm this. Luckily we were only doing 2 knots, having fortunately treated the stated sounding with a little caution, but the impact was a real shock!
The British charts of Finland are of course only good for offshore passages or sticking to big ship channels, Finnish charts are essential for anything remotely off the beaten track. On another occasion we had some 'fun' trying to use a British chart (about 3 years out of date) to enter a fjord at night (definitely not recommended). Two of the four sets of leading lights shown on the chart were either no longer there, or not working...
I sympathise. I hit a rock (made a scratch at the base of the keel) while approaching Jakobsramsjo harbour. It was marked - but with a 4 litre white plastic bottle! In the yard in Sweden where I laid up there were two boats with quite sizebel lumps out of their keels. It doesnt do to be hasty.
I was lucky
I am just thankful we were going slowly when it happened! It must happen frequently to Finnish yachts. I hate to imagine what hitting one at 5 knots must feel like.
I've seen it happen. 20 years ago in Bohuslan the last boat in a race cut a corner, hit the charted rock and stopped dead with a very definite clang. I know of a case in 2000 where the skippers wife went down the companionway, bust an arm and was airlifted out. There are no crumple zones on boats.
English boat told me he'd hit a rock in Arkosund at 3 kts. this season. He'd stopped with the head well down. He dived and found a modest chunk knocked out of his lead keel.
Even a glancing blow as we had with a very shallow scratch makes a nasty noise, the boat draaags snd you get all ahaky.
Yes, it left me with a nervous twitch for several days every time the depth guage started dropping. We needed a stiff vodka afterwards. Ours was also a glancing blow, fortunately, in that we keeled over and skated over the top of it, and down the other side, which must be better than being stopped dead in the water.
I was glad however that my boat (a Contessa) has an encapsulated keel and thick hull build. I am afraid that a boat with a light build and keel bolts could suffer some nasty strain around the bolts...
Its the stout build that matters most I think.
I've also seen a racing 35 or so up on shore at Stavanger with a reprofiled tip to a blade shaped keel and cracks both ends of the root in the hull.
However one of the boats in our overwintering yard had lumps out of both fore and aft tips of an encapsulated fin rudder with possible water ingress into the keel. Ithink he had hit a rock, perhaps bounced over it and backed off hitting it again with the thinner aft side. In any event much sympathy. It was a British boat incidentally.
By the way, we didn't by any chance meet this summer? 'Badger' sounds familiar. Were you by any chance having trouble with a diesel tank in Nynashamn, or have I got you mixed up with someone else?
I spent a fair amount of time in Nynashamn Marina at the beginning and end of the season getting ready for the season and later getting ready for the winter. I had no diesel tank problems as such. Time scale 3-11/6 and 16-21/8
In the early stay I was mostly working on mains rewiring, batteries and charging systems according to my log.