Type 039 Class (Song Class) Chinese Diesel-Electric Submarine

The Type 039 submarine (NATO reporting name: Song class) is a class of diesel-electric submarines of the People's Liberation Army Navy. The class is the first diesel-electric submarine to be fully developed within China and also the first Chinese diesel-electric submarine to use the modern teardrop hull shape. Designed for attacking both other submarines and surface ships with torpedoes, the submarine uses a modern teardrop-shaped hull for underwater performance. The hull incorporates four rudders and is propelled by a single propeller. The engine is imported from Germany. For quieter operation, the engine was mounted with shock absorbers and the hull is plated in rubber tiles for sound deadening. Development was not without problems, as a lengthy testing period for the first vessel (320) attests. Problems with noise levels and underwater performance led to revisions in the design and only a single boat was ever built to the original specification. Improvements led to the specification for the Type 039G, which became the bulk of production, with seven of the type entering service. Elimination of the stepped design for the conning tower is the primary visual cue for the identification of the G variant. This class has two versions: the original Type 039, and Type 039G. The most obvious visual difference between the two types is the conning tower. The Type 039's conning tower is stepped rising aft. In an effort to shrink the submarine's acoustic signature, the Type 039G's conning tower was given a more conventional shape without any step.