OVERVIEW: The PLA-659T Echo I is a submarine of Soviet origin, entering service in 1973. It is classified as a first-generation nuclear-powered cruise missile submarine.

DETAILS: The Echo I class (Project 659) was developed in the late 1950s and early 1960s by the Soviet Union as a response to the growing threat posed by US Navy aircraft carrier groups. The design prioritized the ability to deliver a devastating anti-ship strike from long range. This required a large hull to accommodate the P-5 (NATO reporting name: SS-N-3 Shaddock) cruise missiles and their associated guidance systems. The missiles were housed in six tubes located on the deck, externally mounted and angled upwards for launch. The Echo I design represented a significant departure from previous Soviet submarine designs, focusing on surface-launched anti-ship missiles rather than torpedoes as the primary offensive weapon. This emphasis on long-range engagement dictated a submarine designed to locate and target surface combatants at considerable distances.

The PLA-659T was primarily designed for Anti-Surface Warfare (ASuW) operations. Its primary role was to locate and engage enemy surface combatants, specifically aircraft carriers and their escorts, with its cruise missiles. While not optimized for anti-submarine warfare (ASW) or anti-air warfare (AAW), its suite of sensors provided a degree of self-defense capability. The Wolf Paw (GAS-372 Hercules-2M) sonar allowed for the detection of enemy submarines, although it was not as advanced as dedicated ASW platforms. The vessel also used the Brick Pulp (MRP-21 Zaliv-P) electronic warfare support measures (ESM) suite to identify and classify radar emissions from potential targets, aiding in situational awareness and target identification.

The PLA-659T’s sensor suite and armament reflects its primary ASuW role. The Snoop Slab (Burya) radar provided long-range surface search capabilities, crucial for locating targets over the vast ocean expanses. The Quad Loop DF was likely used for direction finding of enemy transmissions. While the vessel possessed 533mm and 400mm torpedo tubes, these were intended primarily for self-defense or engagement of smaller surface vessels. The installation of the Generic Acoustic Intercept system would allow for the monitoring of enemy sonar activity, providing early warning of potential threats. The Signal Ejector provided a means of underwater communication, though its exact capabilities remain unknown. The combination of the optical periscope and the generic submarine periscope likely provided redundant visual reconnaissance capabilities.

SPECIFICATION: Length: 111.2 m || Beam: 9.2 m || Draft: 7.1 m || Disp: 3830 t

SENSORS: Quad Loop DF || Stop Light B [Nakat] || Snoop Slab [Burya] || Brick Pulp [MRP-21 Zaliv-P] || Generic Acoustic Intercept || Wolf Paw [GAS-372 Hercules-2M] || Generic Submarine Periscope || Optical

ARMAMENT: Signal Ejector || 533mm TT || 533mm TT || 400mm TT