Канадская подводная лодка HMCS Okanagan: История службы и модернизация.

HMCS Okanagan (S74) was an that served in the Canadian Forces (CF). She entered service in 1968 and spent the majority of her career on the east coast. The ship was paid off in 1998 and sold for scrap in 2011.

The Oberon class were considered an improved version of the preceding Porpoise class submarines, with a different frame of the pressure hull and constructed from a better grade of steel. These build differences allowed the Oberons to have a deeper diving depth at roughly 1000 feet (305 m). The boats were powered by a two shaft diesel electric system. The Oberons were equipped with two ASR 1 16 cylinder diesel engines creating and two English Electric motors creating This gave the submarines a maximum surface speed of and a submerged speed of The boats carried 258 tons of oil giving them a range of at 12 knots. The design was armed with eight 21 inch (533 mm) torpedo tubes, six in the bow and two in the stern. They carried 24 reloads for a total of 30 torpedoes. Canadian boats differed from the original design by being equipped for the US Mark 37C torpedo. The longer, wire guided Mod 2 version was carried in the forward tubes and the non guided Mod 0 for the rear tubes. The Oberons were equipped with Type 187 active passive sonar, Type 2007 passive sonar and Type 2019 sonar. In an effort to take the subs from anti submarine warfare training to frontline service, Maritime Command developed a refit program that included new sonars, periscopes, communications and fire control systems. They also had their armament upgraded with the fitting of torpedo tubes capable of firing the Mark 48 torpedo. This would allow the submarines to be deployed by NATO in the North Atlantic to monitor Soviet submarines. The SOUP refits comprised a new US fire control system, a digital Singer Librascope Mark I, and new Sperry passive ranging sonar with the Type 719 short range sonar removed. The new sonar was placed in the upper casing on the pressure hull. New communications and navigational systems were installed. Between 1980 and 1986, one of the Canadian Oberons was out of service undergoing the refit. SOUP came in on time and on its budget of C$45 million in 1986. SOUP kept the Canadian Oberons operational until the end of the 1990s when they were replaced by the British s.

In March 1962, the Cabinet recommended the purchase of three Oberons and eight frigates, on the condition that the cost of acquiring the submarines from the United Kingdom would be offset by British defence purchases in Canada. On 11 April 1962, the purchase was announced in the House of Commons of Canada by the Minister of National Defence, Douglas Harkness. However, the Conservative government postponed the acquisition of the Oberons due to the slow speed of the United Kingdom's attempt to offset the acquisition. The Conservative government was defeated in 1963 and the incoming Liberal government suspended all major defence procurement projects upon taking power. The final price of C$40 million for the entire contract was agreed upon in 1963. However, due to Canadian modifications to the design, that number climbed to C$51.4 million. Since Onyx was already under construction, the boat was finished to Royal Navy specifications. All three boats received modifications to the original Oberon design, which included the enlargement of the snort de icer, a different weapons fit, a larger air conditioning unit, active sonar and different communications equipment. The three submarines were acquired for service as "clockwork mice", submarines used to train surface vessels in anti submarine warfare.

The submarine, built at Chatham Dockyard in England, was laid down on 25 March 1965, and launched on 17 September 1966 by Monique Cadieux, the wife of the Associate Minister of Canadian National Defence. She was commissioned on 22 June 1968 at Chatham. The submarine was named after the Okanagan First Nations people, and was assigned the pennant number S 74. Okanagan spent time training with the Royal Navy after an exchange program was instituted in the 1960s that would see submarines from both the Royal Navy and Royal Canadian Navy spend time with each other's forces. This allowed Canadian submarines on intelligence gathering missions. Beginning in the 1970s, Canada began underwater surveillance patrols in the western Atlantic, tracking Soviet sub and surface fleet vessels, especially the ballistic missile submarines, usually in concert with an Argus or Aurora patrol aircraft. In July 1973, Okanagan collided with the Royal Fleet Auxiliary vessel RFA Grey Rover while exercising in British waters off the coast of Scotland. The submarine was running submerged off the mouth of the River Clyde when the tanker hit Okanagan. There were no injuries to the submarine's complement. However, the submarine suffered damaged to her fin and mast. The submarine returned to Faslane to effect repairs. On 30 June 1983, Okanagan was deployed on a 19 day anti Soviet submarine patrol. Okanagan underwent her SOUP refit beginning in 1984, being handed over to HMC Dockyard at Halifax, Nova Scotia on 2 April. The refit began on 12 June 1985 and lasted until 7 April 1986. Following the SOUP refit and the introduction of the Mark 48 torpedoes, the Oberons were considered fully operational and counted the same as other offensive fleet units in Maritime Command (MARCOM). In early September 1998, Okanagan was used to search the ocean floor for the flight recorders of the crashed Swissair Flight 111 off the coast of Nova Scotia. She was paid off from MARCOM on 12 September 1998. Okanagan was towed to a scrapyard in Port Maitland, Ontario in August 2011.