Submarines are expensive boats to build and maintain, even if they are second hand. Canada wanted to replace it's 1960s era diesel-electric subs, but the cost of new boats would have been be several hundred million dollars each. Britain, however, had four slightly used Upholder class diesel-electric subs that it was willing to part with for $188 million each. Britain had built these boats in the late 1980s, put them in service between 1990 and 1993, but then mothballed them shortly thereafter when it decided to go with an all-nuclear submarine fleet. So the deal was made in 1998, with delivery of the Upholders to begin in 2000. Canada decommissioned its Oberons in 2000, then discovered that the British boats needed more work (fixing flaws, installing Canadian equipment) than anticipated. At the moment, the first of the Upholders won't be ready for service until 2004. The Upholders are now called the Victoria class, and are much more modern and capable than the older Oberons. The Victorias are 2160 tons (displacement on the surface), have a crew of 46, and six torpedo tubes (and 18 Mk 48 torpedoes.) The electronics on the Victorias are state of the art and a primary reason for buying these boats second-hand. The subs will be used to patrol Canada's extensive coastline. The passive sonars on these subs make it possible to detect surface ships over a great distance. But not having any subs on active duty for four years has become a major issue in Canada.