Complex sentence: A direct hit by one of the B-17's bombs exploded two of the Type 93 torpedos on "Aoba", and the flooding ship was beached to prevent her from sinking.
Split into simpler sentences: A direct hit by one of the B-17's bombs exploded two of the Type 93 torpedos on "Aoba", causing the ship to begin to flood. The ship was beached to prevent her from sinking.