As it was believed that further aircraft carrier raids would be fruitless due to shortcomings with the Royal Navy's aircraft and their armament, responsibility for sinking "Tirpitz" was transferred to the RAF's Bomber Command. On 15 September 1944, the elite Nos. 9 and 617 Squadrons attacked the battleship at Kaafjord during what was designated Operation Paravane. This operation employed Avro Lancaster heavy bombers armed with Tallboy bombs and "Johnnie Walker" mines, and was mounted from Yagodnik in the Soviet Union. "Tirpitz" was struck by a single Tallboy, which caused extensive damage to her bow and rendered her unfit for combat.