Got into Loch Ewe, in my IID in November 39, wiggled my way over sand bars only 4m under my keel and got between HMS Nelson and the island in the middle of the loch. Sank her with 3 eels under the belt from 345m and none of the destroyers could get me cos the carcas of Nelson was blocking the way!
one did get round the end, but could't turn fast enough and ran it's self aground. I made a sharp exit and sank a small Merchant on the way home with my last eel.