This was a British programme of naval minelaying operations off the ports of Boulogne and Dieppe in German-occupied northern France (October/November 1944).
In British home waters and off North-West Europe, there had been complex and widespread British minelaying operations in the first half of the year in support of the forthcoming ‘Neptune’ (iii) and associated 'Overlord'. These operations were carried out by surface vessels, including many by light craft of the coastal forces, and by land-based aircraft. In addition a series of minelaying operations by carrierborne aircraft was carried out in the waters off Norway. As military activity in the Italian theatre was restricted almost entirely to the mainland, the only minelaying in the Mediterranean was in defence of ships involved in landing operations.
Minelaying support for ‘Neptune’ (iii) was part of the ‘Maple’ overall plan, and as part of this surface minelayers were used mainly in the second and third phases. The responsibility for the implementation of these undertakings was vested in the commanders-in-chief at Plymouth for the ‘Hostile’ series, Portsmouth for the ‘KN’ series and the Nore for the ‘QU’ series, together with the flag officer at Dover for the ‘NL’ series.
These operations were intended to provide protection for cross-channel convoys against attacks by S-boote and R-boote, and amounted to 39% of the total number of mines laid. Surface ships other than coastal craft laid 1,420 mines out of the total naval contribution of 2,891. The newly commissioned fast minelayer Apollo laid minefields off Brittany to deter use of the Western Approaches to the Channel from the Bay of Biscay (1,170), and Plover was deployed to lay mines in the Eastern Approaches (250).
During August increased levels of U-boat activity caused losses of shipping on passage to the Normandy beach-heads supporting ‘Overlord’, and a series of deep anti-submarine minefields was laid by Plover under these routes in ‘Pasture’. When the U-boat bases along the coast of the Bay of Biscay were occupied or effectively neutralised, this series was discontinued. Considerable effort was also expended to provide additional deep anti-submarine minefields in the South-Western Approaches to the Irish Sea and later during November in the North-Western Approaches off Malin Head. During December, increased U-boat activity was anticipated in the inshore waters off the north coast of Cornwall, and Apollo and Plover laid deep anti-submarine minefields.
Along the coast of German-occupied Norway, minelaying was intensified very considerably after the threat posed by major German warships had been ended. Seven offensive mining operations were carried out in Norwegian coastal waters by aircraft of the Home Fleet’s aircraft carriers, and another three by a Free French submarine.