'DB' (iv) was the British purely naval part of 'Ploughshare' to deliver reinforcements and stores to the British and Canadian garrison on Spitsbergen island off the north coast of German-occupied Norway (16/24 June 1944).

The light cruiser Jamaica, escorted by the destroyers Wager and Whelp, had departed Scapa Flow in the Orkney islands group and reached Glasgow on 14 June to embark the stores and a few LCV(P) light landing craft, and returned from Spitsbergen island to reach the Clyde river once more on 24 June.