1944年4月下旬,德国海军U-198潜艇从西班牙比斯开港启航,驶往印度洋,开始执行第二次作战巡逻任务。途经南大西洋时,U-198艇先后击沉了商船“科隆拜恩”号、“迪雷克托”号、“自由”号及“帝国城”号,而它几次三番仅遭轻微损坏便死里逃生。被激怒了的英国皇家海军于是出动航母、护卫舰、飞机及印度海空军兵力,在印度洋莫桑比克海峡,与德国海军U-198潜艇展开了一场“猫捉老鼠”般的反潜大战。 In late April 1944, the German Navy U-198 submarine sailed from the port of Biscay, Spain, and headed for the Indian Ocean to begin its second combat patrol mission. When passing through the South Atlantic, the U-198 boatman sank the merchant ships “Cologne Byrne”, “Di Recto”, “Liberty” and “Imperial City” successively Several times only minor damage will escape. The infuriated British Royal Navy launched its “cat-and-mouse” antisubmarine war against the German Navy’s U-198 submarine in the Indian Ocean over the Mozambique Channel by dispatching aircraft carriers, frigates, aircraft and Indian naval and air forces.