 Several air and naval attacks were launched against Tirpitz in 1942 and 1943. On 6 March 1942, torpedo bombers flying from the aircraft carrier HMS Victorious attacked the battleship while she was attempting to intercept Convoy PQ 12 but did not achieve any hits. Land-based bombers from the Royal Air Force (RAF) and Soviet Air Forces also attempted to strike Tirpitz in her anchorages on several occasions in 1942 and 1943, but did not inflict any damage. On 23 September 1943, two British X-class midget submarines penetrated defences around the battleship at her main anchorage at Kaafjord in northern Norway during Operation Source, and placed explosive charges in the water beneath her. This attack caused extensive damage to Tirpitz, putting her out of service for six months.
