The modern conventional submarine
Inside German WW2 submarines
USS Long Beach
The nuclear attack submarine in the East
Soviet SSN were of the most innovative in their type, for they were the first ones in adopting titanium hulls, which allowed greater operating
depths, and speeds above 40 knots, thanks to their reactors cooled by liquid metals. The "saga" started with the November class, commissioned between
1958 and 1963, a twin-propeller design of high acoustic signature, armed with eight 533-millimeter torpedo tubes prepared for torpedoes and mines only.
The following class was the Echo, which used two five-bladed propellers and whose acoustic signature had been notably reduced, however being still
higher than in western counterparts.
The Victor class, whose three different series entered service between 1967 and 1984, were of single shaft, with two emergency propellers and a
hydrodynamic hull. Their armament comprised a mixture of 533 and 650-millimeter torpedo tubes, which could fire torpedoes with nuclear warheads,
cruise missiles SS-N-21 and antisubmarine missiles SS-N-15, or lay mines. Their maximum operating depth is 400 meters, with a probable collapse depth
of 600 meters. As 2016, four vessels of the third series (of a total of 48 vessels completed for the whole class) still remain in service.
Between 1971 and 1981 entered service the seven vessels of the Alfa class, whose titanium hull allowed them to reach depths of up to 700 meters,
never reached before, and to considerably reduce their magnetic signature. The propulsion plant was not less innovative, for its two reactors used a
coolant based in liquid bismuth-lead, allowing speeds over 40 knots while in immersion. However this system greatly reduced the
lifetime of the reactor. This combination of high speed and depth caused great concern in the western navies. The armament comprised six
533-millimeter torpedo tubes which could launch antisubmarine missiles SS-N-15 or lay mines. All the vessels except one remained operative
until the end of the Cold War.
Between 1986 and 1992 were built the four vessels of the Sierra class, which remain currently operative. They were made to counter the American
SSN of the Los Angeles class. As their predecessors they have a light but strong titanium hull which allows them to dive deeper, to be more silent
and to better whitstand any possible impacts. But unlike the preceding class, they are powered by the usual water-cooler reactor. They are armed
with four 533 and four 650-millimeter torpedo tubes, which can launch antisubmarine missiles SS-N-15, antiship missiles SS-N-16 and cruise missiles
SS-N-21 fitted with conventional or nuclear warhead, or lay up to 42 mines. They are superb attack submarines but their weak point is their price
and because of this no more units were produced.
The Akula class, of which fifteen vessels were completed, was developed as a more affordable version of the Sierra class. Its silent speed reaches
28 knots while in immersion and it improves acoustic and magnetic signatures. The armament is similar to that of the previous class.
A submarine of the Akula II class was leased to India in 2012 for a ten-year period, being currently this one the only SSN operated by said country.
The following picture shows a comparison of Soviet attack submarines (including those of conventional propulsion) with the most important type
of attack submarine in service with the US Navy in 1989, Los Angeles class. Other attack submarines then in service with the US Navy
were those of the classes Skate (1957), Skipjack (1959), Permit (1961) and Sturgeon (1967).
The last SSN deployed by Russia is the Yasen class, of which two units have been completed as 2016. This class is heavily armed with ten torpedo tubes
(eight of 650 millimeters and two of 533) and eight vertical launchers for antisubmarine/antiship cruise missiles SS-N-26 and SS-N-27. The size
and propulsion plant are similar to those of the Akula class, as well as its prestations.
On the other hand, the People's Republic of China commissioned its first SSN in 1974, which was followed by other four vessels of the Han class.
As 2016 three of these submarines are still in service. They are armed with six 533-millimeter torpedo tubes and are capable of a speed of 25 knots
while in immersion. These submarines have been highly criticized for having a noisy reactor and poor radiation shielding, which causes health hazards
for their crewmen. But also because they are uncapable of launching missiles while submerged.
Their successors are the five vessels of the Shang class, of which at least two have been already commissioned, the first one in 2006. They are somewhat
larger, with a length of 110 meters and a maximum displacement of 7000 tonnes. They are also capable of rather higher speeds, up to 30 knots while
submerged. They are armed with six 533 or perhaps 650-millimeter torpedo tubes and - allegedly - with a vertical launching system for antiship missiles
YJ-18. It is also quite controverted their actual level of acoustic signature.