Such is titanium, a light metal of great strength, that has been even used in sporting equipment, and military hardware, although it never entered into U.S. aircraft; nonetheless, the Soviet Union did use it in constructing its submarines, including the Sierra II-class.
The Sierra II-class or Project 945A Kondor is one of the most advanced and expensive types ever produced. To mention, the deep diving and low noise design for these submarines were thanks to their hulls, which are mostly made of titanium. However, this high cost and complexity when dealing with the use of titanium limited its production.
Even though the Sierra II-class, Nizhny Novgorod and Pskov being examples, do boast impressive capabilities, it has spent most of its time in port lately. They don’t go out to sea too often anyway. The Soviet Union’s first use of hulls made from titanium was with the Alfa class, but that is a very poor material to work with. Argon was also used to fill enormous hermetically sealed warehouses designed by Soviet engineers to which to weld the titanium panels. Large cosmonaut-like suits were also used in providing welding operators with oxygen, and a stumble of the welding operation could easily compromise the integrity of the submarine’s hull.
The Sierra II class was designed in reply to the Sierra I. Their first-line mission was the search for and destruction of U.S. nuclear-powered ballistic missile submarines. The lightweight, yet extremely strong, titanium twin-pressure hulls gave them a greater diving depth while emitting less noise and resistance to torpedo attacks. They were equipped with one OK-650 pressurized water reactor rated at 190 MW. These submarines were built to be able to attain a speed and a depth that no submarines in the US could reach during that time.
There are still two Sierra II-class submarines, Pskov (ex-Zubatka) and Nizhny Novgorod (ex-Okun), in the Russian Navy’s Northern Fleet. Mars is another submarine that was laid down in 1990; by 1992, the submarine had been scrapped before it was completed. Due to the highly expensive material and significant problems that were involved while working with titanium, none of the Project 945A Kondor Class were ever built.
Not much has been said or heard of the two Project 945A Kondor Classes in the recent past. In a report from state media outlet Tass from November, it was noted that drills conducted under the Nizhny Novgorod and Pskov submarine included underwater dueling with torpedo practice fire. “The crews of the Northern Fleet’s multipurpose nuclear-powered submarines Nizhny Novgorod and Pskov performed planned assignments in the Barents Sea… Torpedo practice fire against surface targets was the most complex and responsible stage of the joint underwater maneuvers,” the press service of the Northern Fleet of the Russian Navy reports.
Maneuvering for combat and attacking and breaking off from the enemy contact was maintained with more steady exercise, making use of jamming and decoy targets. For over four years since release, however, there has hardly been a word about these boats, and it is assumed that they seldom go out of port.
The history of the development of the Sierra-class submarines started in 1971 with a decision taken by the Lajurit Design Bureau to create the project of a third-generation attack submarine.
That decision was unlikely, since long ago the Malachite Design Bureau was mainly involved in the attack-submarine design. Bad experience with the operation results of the Alpha-class attack submarine designed by the Malachite Design Bureau probably acted as a stimulus for this decision.
The Sierra-class submarines have been designed for long-term operations and were oriented and built with an eye to quietness as they have to sneak into the opponent’s front yard.
The portion of the hull is made from titanium, and it boasts really deep diving depth and incorporates traditional double-hull attributes. According to Norman Polmar’s book “Cold War Submarines,” it received a test depth of 600m, more than other submarines that could compromise on the diving depth in favor of other required performance.
The Soviet Navy placed an order for over 40 Sierra-class submarines, but it managed to receive just four because these were highly expensive to manufacture.
Among the four, there are two Sierra I-class submarines and two Sierra II-class submarines. This is because the hull is made of expensive titanium, and also, a new titanium alloy processing facility was constructed at Krasnoye Sormovo Shipyard.
Whereas the four 650mm and four 533mm torpedo tubes forward are featured in Sierra I-class, six 533mm torpedo tubes are featured in Sierra II-class.
Torpedoes and cruise missiles in the Sierra I-class and Sierra II-class have a capacity of 40, much higher than all Russian-made submarines available in the market. The warhead in a 650mm wake-homing torpedo is more than 500kg. It can neutralize the largest targets with just one shot.