collided with the Norwegian merchant ship , which sank, killing five aboard the merchant ship. Leamington was under repair at Liverpool until July that year, when she rejoined the 2nd Escort Group, which moved to Iceland in September. On 11 September, the 2nd Escort Group, including Leamington was sent to reinforce Convoy SC 42 under heavy attack off the east coast of Greenland from the U-boats of the wolfpack Markgraf, which had sunk 15 ships from the convoy already. On the afternoon of 11 September, Leamington and the destroyer were sent ahead of the convoy to investigate a sighting by an aircraft of a submarine ahead of the Convoy. The two destroyers spotted on the surface and carried out a series of depth charge attacks against the submarine, which was destroyed with no survivors. On 23 March 1942, the fast troop convoy WS 17 set out from the United Kingdom to Freetown, Sierra Leone, with Leamington part of the convoy's escort. On 27 March 1942, the German submarine sighted the convoy, and radioed a sighting report with the hope that other U-boats could be directed to attack the convoy. The destroyer picked up the transmission, and used High-frequency direction finding (HF/DF) to direct an attack against the German submarine by Leamington, , and . They attacked and sunk U-587 with depth charges, the first submarine sunk with the aid of shipboard HF/DF. On 27 June Convoy PQ 17 set out from Iceland for Arkhangelsk in the Soviet Union, with Leamington joining the convoy's close escort on 30 June. On 4 July, believing that the German battleship and other heavy ships had sortied against the convoy, the British First Sea Lord, Admiral Dudley Pound ordered that the convoy be scattered, with the escort, including Leamington, being withdrawn to the west. This exposed the lone, unescorted ships to continued unopposed attacks by German U-boats and aircraft. In total, PQ 17 lost 24 of 36 merchant ships, with 21 sunk after the order to scatter. Leamington was refitted at Hartlepool, England, between July and November 1942. On 12 November, the Panamian registry merchantman SS Buchanan was torpedoed by . Thirteen days later, Leamington—assisted by aircraft—located one of the freighter's four lifeboats and took aboard its 17 uninjured sailors. Royal Canadian Navy service In November 1942, the Royal Navy transferred Leamington to the Royal Canadian Navy, joining the Western Local Escort Force, escorting convoys