Soviet Century/Cold War 2020 AU

Submarine design had long been a favored branch of Soviet shipbuilding, and one which gave birth to a large amount of unprecedented designs. Characteristically, while most submarine-building countries were striving to standardize their fleets to only a handful of classes, the Soviet Union kept on average three to four classes building at the same time for many decades. The historic insistence on submarine anti-ship warfare and the dichotomy between high-seas high-performance submarines and coastal patrol ones were driving factors in the long term co-existence of very varied classes, while very ambitious designs kept being refused for mass production for cost reasons and giving way to separate low-cost substitutes in all classes. Fromt he 1980s onward, design branched towards more potent diesel-electric patrol submarines as well as more compact missile-carrying models enabled by miniaturized anti-ship missiles and control systems. In turn, this change led to a drastic reduction in the number of hulls, with diesel submarines down nearly 70% between 1980 and 2000 due to the retirement of post-war boats. With the improvements in sensors, weapons and C4I barely compensating the loss of platforms, design bureaus turned their efforts towards the development of smaller, cheaper hulls that could be deployed more extensively. The Project 662 Kalkan was the result of that effort in non-nuclear submarines, building on the experience of fourth-generation subs.

Pr.662 Kalkan
Small submarines had mostly fallen out of fashion by the late 1950s in favor of long-range oceanic patrol submarines, and the drive for smaller boats required designers to exploit all the latest advances in miniaturized C4I systems, high-density batteries, multi-frequency conformal sonars and small-caliber multi-target torpedoes and missiles that made submarines below 1000t displacement viable again by the late 2000s.
While this had not escaped smaller navies operating in constrained environments such as West Germany, Denmark or Israel, the Soviet Navy was just starting to adjust to a world where abundant manpower and surplus ships would be less taken for granted than opponents with smart mines and stealthy submarines.

Despite its small size, or possibly thanks to it, the Project 662 design was very modern, with an outer hull built out of glass-fiber composite and sophisticated systems, such as a shrouded propellers and obstacle-avoidance LIDAR scanners, along with equipment generally associated with ocean-going nuclear submarines: a crew escape capsule, crawl propulsors, and an extensive array of noise jammers. Despite its inherently limited range, the Pr.662 hull was optimized for maneuvering far beyond previous generations. Where earlier diesel subs could mostly serve as commerce raiders and a last-ditch deterrent for amphibious landings, these boats were meant to tangle with high-end adversaries in their own coastal areas. Whatever the technical advances underwriting the design itself, its very capabilities hinted at a heightened sense of menace within the Soviet naval establishment. More than at any time in the previous three decades, Soviets strategists were genuinely afraid of a penetration of their coastal approaches by technologically superior enemy forces. This perception was partly a long-term offshoot of the ingrained resentment of US adventurism in the 1980s, and partly supported by experiences of the Yugoslavian Partition war and the ensuing tensions in the Black Sea. Near-war skirmishes and escalation in Soviet and allied coastal areas could not be discounted anymore, and the legacy structure of surface ships and air platforms could not efficiently provide the tactical overview needed against agile and stealthy infiltrators.
The combat endurance and flexibility of the class were improved by the adoption of the 400mm torpedo tube in replacement of the earlier 533mm standard. By the mid-2000s, improvements in torpedo propulsion and guidance enabled smaller-caliber torpedoes to match the performances of heavier weapons ten years earlier, in turn allowing designers to equip low-displacement ships and subs with lighter weapons. Even the 700-ton could carry over a dozen torpedoes and missiles, giving it as many engagement chances as foreign designs twice the size.

The class would see widespread service in the Soviet Navy and be exported to numerous foreign navies wishing for a low-impact submarine capability. Export quantities would nevertheless be limited by the sophistication and cost of the design, several countries preferring the larger but more straightforward Project 950. Following their strategic rapprochement with the Soviet Union in 2013, Iran would nevertheless acquire their own production license for the class.

[ img ]

Pr.662.1 Kalkan-SN
An extended version of the Pr.662 with an AIP module had been in the works since the beginning of the project. Based on research work on Project 947, Project 662.1 made the jump directly to a hydrogen-based fuel cell system to supplement the baseline lead-acid batteries, the reactor being housed in a 5.8-meter hull plug aft of the main engines. To the surprise of some analysts, the initial version turned out to use the extra hull length not for missile tubes, but for a pair of enclosed docking bays for USVs, ROVs and other submarine vehicles, as well as two double-ended flooding pressure locks for divers.
The extra equipment and structures ended up eating up enough of the added space to require halving the fuel supply for the AIP module, the remainder still doubling the submerged range over the original model.
A dozen ships of that class would enter service, being divvied up between all Soviet fleets, their peacetime missions revolving mostly around minefield inspections, bottom profiling and the odd clandestine action on NATO underwater communication lines and sensors. True "Special Purpose" mission would be aided in due course by the addition to the loadout of a family of modular ROVs that could easily be reconfigured dock-side for mine-clearing, wire-tapping or mapping missions. Understandably, none of this would ever be exported to client states, though the Kalkan-SN subs would sometimes be spotted in friendly ports far from their home waters, signalling Soviet interest in local event as clearly as major surface ships.

[ img ]

Pr.662.2 Kalkan-R
Two factors converged at the end of the 2000s to give birth to the missile-carrying Pr.662.2 Kalkan-R, arguably the smallest serious SSG then in service. Ongoing work on the AIP-equipped Pr.652.1 provided the blueprints for a lengthened hull, while the start of Project 676M and of the modernized Project 950 gave impetus to the integration of separate missile launchers in coastal warfare submarines. Original plans calling for a through-hull missile module similar to most SLBM installations were rejected mid-design in favor of smaller tubes sitting between the inner and outer hulls. While this had the advantage of limiting pressure hull penetration and therefore ship vulnerability, it pushed the inner hull to shrink locally to accommodate the missile tubes without forcing a hydrodynamically significant redesign of the outer hull. The final configuration carried only 4 tubes per side, still tripling the usual missile allocation of the torpedo-tube variant, and guaranteeing a multi-mission loadout.

This spread of - potentially nuclear - cruise missiles to an unprecedented amount of small hulls gave pause to NATO diplomats, who started unsuccessfully pushing for bilateral limitations on at-sea cruise missile platforms, like their Soviet counterparts had tried in the 1990s. It would take many more years for a global cap on naval cruise missiles to be enacted in a bilateral arms reduction treaty, at which point deployment was so widespread as to make limitations either meaningless or inapplicable.
The Pr.662.2 would completely replace the original Pr.662 in production, profoundly expanding the missile capacity of the coastal submarine units, while a few would be exported to the most trusted client nations.

[ img ]

Shipbucket

Who is online