Complex sentence: The "Aikoku Maru" soon avenged her sister ship, scoring several hits on "Ondina", but shells and torpedoes have little effect on empty tankers, as the large number of watertight tanks keeps them afloat under the most difficult circumstances.
Split into simpler sentences: The "Aikoku Maru" soon avenged her sistership, scoring several hits on "Ondina". Fortunately, shells and torpedoes have little effect on empty tankers, as the large number of watertight tanks keeps them afloat under the most difficult circumstances.