The Biggest U-Boat Surrender -- Three of the surrendering U-Boats. Fifteen U-boats, in two columns and escorted by H.M. ships and aircraft of the Royal Navy, approached Loch Eriboll on set; 19th May, 1945. The U-boats were contacted off the Norwegian coast and ordered to congregate in a fjord. Then under the instructions of the senior R.N.Officer, the biggest surrender convoy proceeded in good order to the North West coast of Scotland during the week-end. The U-boats are remaining at Loch Eribol