“The U.K. called in assistance to help hunt for a foreign submarine off the west coast of Scotland starting in late November. Maritime patrol aircraft (MPAs) from France, Canada and the U.S. conducted patrols in conjunction with British surface warships in the search for the submarine in late November and the first week of December, operating out of RAF Lossiemouth in northern Scotland.”
Source: Canadians, French, U.S. Hunt For Submarine Off Scotland | Defense content from Aviation Week