Complex sentence: One of the main weaknesses of the "Draug" class ships was their lack of effective anti-aircraft armament, "Draug" herself being equipped with a single 12.7 mm Colt anti-aircraft machine gun and a Madsen machine gun rendered inoperable by the absence of a vital part.
Split into simpler sentences: One of the main weaknesses of the "Draug" class ships was their lack of effective anti-aircraft armament, "Draug" herself being equipped with a single 12.7 mm Colt anti-aircraft machine gun. She also carried a Madsen machine gun that was rendered inoperable by the absence of a vital part.