Fourth generation Non-Nuclear Submarines (NNS) in struggle for markets
In 1980s the two world powers - the USSR and the USA - got down to design of the fourth generation of the non-atomic submarines which differ from their predecessors on higher combat effectiveness achieved by implementation of the latest achievements in nuclear engineering hydrodynamics, weapons, construction materials, stealthiness, submarine acoustics and not acoustic means of submarine detection, automatic control systems, communication etc. As a result such submarines as "Seawolf" (entered the service in 1997) and "Virginia" (entered the service in 2004) multi-purpose submarines as well as Project-885 and Project-955 Russian nuclear propulsions (their entering the service of the Naval forces is expected in 2008-09), the French "Barracuda" nuclear submarine (the forerunner was laid down in 2007) and the British "Ascute" (2009) appeared.
Some time later in 1990s the construction of the first NNS of the fourth generation was started in Germany, France and Russia. Today they are in fierce competitive struggle for the international market of under-water weapons.
Today the total amount of the NNSs in the fleets of 44 states is about 400. These ships play both tactical and strategic role providing even small countries which have submarine forces with the possibility to damage larger and stronger enemy during naval operations. That is why the world market of NNS appears to be highly profitable, prospective and capacious. Its peak increase can be even in the next decade when full range substitution of the third-generation submarines will begin in many countries.
However, the NNSs (which can be referred to as diesel-electric) were in the "shade" of their nuclear "sisters" in 1960-1980s. I
ts enough to say that one of the super-powers, the US, rejected the idea of development of these ships (excluding the development of special purpose submarines and deep-sea vehicles). From 1950s US NATO allies started the development of the NNS projects. The second world leader, the USSR, unlike the US needed both ocean-going and sea-going ships (The Baltic and the Black seas have international non-nuclear status). The USSR developed its diesel-electric submarines according to so-called "residual principle" investing the bulk assets and resources of the military-industrial complex into upgrading of its nuclear submarine fleet first of all.
The submarine ship-building (even in its non-nuclear part which seems easier at first) remained high-tech and science-intensive area and demanded powerful engineering and production base which in its turn demanded enough large means and assets for development. With growth of its complexity and science-intensiveness the number of the states capable to project and build not nuclear submarines independently constantly reduced.
If in 1950 - 1960s the diesel-electric submarines were produced by practically all leading ship-building powers of Europe - England, the Netherlands, Spain, Italy, the Western Germany, France and Sweden. By 1990s only Germany, France and Sweden remained in the European «club of not nuclear submarines producers». Other countries preferred either to buy NNS abroad or to build them under foreign licenses.
At the same time submarines still remained one of most effective means of the armed struggle on the sea. And if in 1950-1960s the demand for them was appreciably satisfied with modernized American or Soviet submarines of military series as well as the submarines of the first post-war generation in service with the Naval Forces of the USSR and the USA, in 1970s the first place (after the Soviet ship-building industry, and the Chinese, who duplicated the Soviet diesel submarines of the first generation in great quantities) was occupied by English, German and French ship builders. In particular, the German Type 205, Type 209 submarines and their numerous variants got the world wide recognition. The submarines of Project-209 have really got the world-wide recognition: in 1970-2000s 63 submarines of this type of various modifications have been delivered in 14 countries of the world. Under the German license their assemblage was carried out in Argentina, Brazil, India, Turkey, South Korea.
Approximately at the same time (1974-2006) France built 13 submarines of "«Agosta»" type. Four of them were given to the national fleet, four - for the Spanish Navy and five - for the Pakistani Navy.
Japan was one of the most active in diesel-electric submarines production countries. The country used its own projects and built several series of relatively large (2500-2800 m3) ocean-going submarines of the second and the third generation which had "albacore"-type hull (the export of weapons and combat vehicles is prohibited in the country by the law). China in parallel with buying of the Russian submarines of the third generation (Projects 877 and 636) produces so-called national "clones" of this submarines and the ships of its own projects using Russian and French technology.
The evolution of the diesel-electric submarines of the second and the third after-war generations (both Russian and Western) was going on along with the modernizing the nuclear propulsions in the way of increasing stealthiness, depth of submersion, self-sustained period, combat possibilities of the weapons and other parameters. The growing demand for diesel-electric submarines in 1970s led to restoration of interest for airindependent non-atomic power plants for submarines which were concerned as auxiliary power plants ensuring the under-water self-sustained period at low speed by two-three (and more) times.
It is necessary to tell that in 1940-1950s the work in this direction was actively conducted in the USSR, the USA and the Great Britain. However after occurrence of the first underwater atomic-powered vessels the interest to such projects considerably decreased for more than a decade having revived only after the diesel-electric submarines proved the capability to be applied effectively even in "atomic age" successfully supplementing incomparably more expensive and sometimes less effective nuclear propulsions.
In 1996-1997 three submarines of "Holland" type entered the service of the Swedish fleet. They conditionally can be corresponded to generation «3 +». The ships with displacement of 1300/1600 м3 and the length of 60.4 m which were constructed on the shipyard in Malino representing further development of diesel-electric submarines of the 3rd generation of the "Vaster»Gotland»" type, have lower noiseness and equipped with modern radio-electronic equipment and weapons. However their main feature is presence airindependent power plant which includes Stirling engines.
Works on this engine began in Sweden in 1960s, and in 1989 the test submarine (converted "Nacken" diesel-electric submarine), equipped with Stirling engines was tested. Unlike diesel engine (where fuel burning occurs in the cylinder under the piston), in the Stirling it is performed in the separate cmbustion chamber. The heat is transferred to a working body (inert gas) which is in the cylinder which actuates the piston. Thus the products of combustion which are under high pressure, are released out board without the additional compressor.
The successful end of the experimental works has allowed the Swedes to start design of high-grade combat submarines. On each of thr "«Gotland»s" two engines of external combustion with the capacity of 75 kw were installed. Soon in the same way with «Gotland» and its «sisterships» two submarines of the third generation of Vaster "Gotland" type were modernized too in Malino. Thus the Swedish fleet was the first in the world to equip fully the underwater forces with NNSs with airindependent power plants.
Power plants with Stirling engines provide the submarine at a speed of 2.5 knots with the duration of the underwater course equal to 20 days. The submarine can go with a speed of up to 20 knots using accumulators. The weak points are - the efficiency is less than a diesel has, big noiseness, leaving trace, and restriction on depth (which, however, is not critical for the Swedish submarines, owing to hydrographic features of the Baltic having working depth of only 150 m).
With the experimental purposes the Swedish engines were bought by Australia. And in Japan with the same purposes the "Asahio" submarines ("Harushio" type) were converted for the Stirling engines. In 2005 the «Gotland» submarine was taken in leasing by the US Navy. According to the official version the US is going to use it for working off of the measures for struggle with perspective anaerobic NNSs of China. However it is most possible to assume, that the Americans simply wish to return to rather perspective international market of NNS and make up the missed opportunities by using actively the advanced European experience for this purpose. At the same time there is no information on contracts on delivery of new boats of the «Gotland» type or on the beginning of building of submarines with the Stirling engines in Japan which also has selected «the Swedish way». The plans of new generation boats with the Strerling engines in Sweden left without continuation.
In 1994 the government of Germany signed the contract on purchase of four submarines of Type 212 which are the new, fourth generation of NNS. The development of these ships was preceded by long works in the sphere of anaerobic power plants of various types, which had been performed in Germany since 1970s. As a result, in the early nineties, after carrying out of numerous experiments and tests (including the tests on the experiment ship - the U-1 Type 205 submarine), the German experts chose the power plant with electrochemical generators (ECG).
This device provides direct transformation of chemical energy into electric, which is carried out in special electrochemical elements (cells). PP with ECG has a number of important advantages to not nuclear airindependent plants of other types - steam turbines of the closed cycle, Stirling engines, diesel engines of the closed cycle, etc. In particular, at rather high efficiency electrochemical generators possess low level of oxygen consumption, have a small thermal emission, and at the output only one product, water, appears.
It is necessary to consider the following points as serious, basic weak points of ECG. First of all, the difficulties with storage of hydrogen: it is dangerous to store it onboard a submarine in the form of the compressed gas or peroxide, and in a liquid condition (with reference to conditions onboard a submarine) - it is extremely technically difficult. The German experts have selected the way of storage of hydrogen in metal-hydride accumulators (so-called intermetallic storage) at which emptiness in a crystal lattice of metal are filled with atoms of hydrogen. However for charging of such batteries "smooth" conditions which can be created only on well equipped coastal base are required. As a result the ship becomes rigidly bound to the limited number of basing sites, which essentially limits its application.
The architecture of the German boat of the 4th generation essentially differed from shape of German submarines of previous generations. The ship has extremely svelt (earlier not peculiar for German submarines) contours with a protection of sliding devices, smoothly «plane likely» interfaced to contours of a superstructure and reminding "cabins" of limuzine type Soviet nuclear propulsions of the 2nd and 3rd generations. It is necessary to tell, that close contours are considered also by the Americans within the framework of works at nuclear propulsions of the 6th generation whih should replace "Virginia" in 2020s.
In 1996 Naval Forces of Italy for which it was necessary to fill up the fleet with at least two new submarines in 2000-2010 joined the German program of design of 212 type submarine. The «Romanized» project of the submarine was designated as Type 212А.
The first boat of Project-212 - U31 named "Wittenberg" was laid in July, 1998, in Kiel on "Howaldswerke Deutchewerft" and was floated in April, 2002. On October, 19, 2005 this ship as well as the second boat of the same type - U32 "Edenkoben" constructed by "Tissen Nordtzeewerke" (Emden) - in solemn conditions were transferred to the fleet. Thus the German Naval Forces after 1969 for the first time were replenished with new submarines. In 2006 the Naval Forces of Germany received two more boats of the given type.
The Italian NNSs Type 212А are under construction on shipyard in Finkantieri (their enering the service is expected in 2009 and 2010), differ from the German "elder sisters" in a number of insignificant features of design and equipment set in which the interests of the Italian manufacturers are taken into consideration.
On Greek shipyard "Helenik Shipyard" two boats of Type 214 which are the export version of Type 212 are under construction for the Naval Forces of Greece. They have increased to 65 m length and less powerful PP with ECG. The surface displacement of the boats is 1600 м3. The head Greek ship "Palanicolis" was floated in April, 2004. Three more NNSs of Type 214 according to the contract signed in 2000 are under construction in Korean Republic for the national Naval Forces. Turkey declared its desire to buy six boats of Type 214. Brazil and the Republic of South Africa became potentcial buyers of these boats in 2008.
The Type 212 boats having surface displacement of 1450 м3 and underwater displacement of 1830 м3 are made in one-and-a-half type (which is caused by necessity to generate volumes for components of ECG). The X-shaped tail plumage (which was earlier made at a number of the 3rd generation submarines which are produced in Germany for a number of foreign customers) rather seldom applied in underwater shipbuilding is another feature of configuration of these submarines. The strength hull of the ship is made of low-magnetic steel, and the external hull and the protection of sliding devices are made of fiberglass.
Power plant of the boat includes usual diesel-electric PP, added with the electrochemical generator. The rowing electric motor with the capacity of 3875 h.p. actuates seven-bladed quiet rowing screw with crescent-type blades. The capacity of ECG is about 306 kw (nine generators with 34 kw each) which provides the boat with full underwater speed of 8 knots, and cruiser speed of 3 knots. Type 212 according to the statements of company representatives is capable to go in underwater position for 14 days (the range of a course is about 1700 miles). With the diesel engine, at cruiser speed of 8 knots, the range is 8000 miles, at a course with only accumulators the boat is capable to cover 420 miles at a speed of 4 knots.
Type 212 and Type 212А NNSs have length of 55.9 m and full speed of underwater course of 17 knots (according to other information - about 20 knots). The maximum depth of submersion is 300 m, self-sustained period - 30 days. Submarines are equipped with six 533-mm torpedo tubes with munition of 12 torpedoes (the regular weapon of the German submarines is the newest electric torpedoes DM2A4 with the maximum speed of an underwater course of about 50 knots and the range of about 20 km. Instead of it the boat can carry mines). The NNS crew is 27 persons. Cost of one serial ship of Project-214 is estimated (depending on the set of equipment and weapon) is 300-350 million euro.
The competitor of Type 212/214 is the "Scorpen" submarine which designed by French DCN company together with Spanish Izar (former Bazan). The new submarine is the further development of the 3rd generation "Agosta" boat. At its development the experience of design and operation of the French atomic-powered vessels (in particular, tiny "Rubis" nuclear propulsion) was widely used. The project has three variants. The choice is defined by desire and financial possibilities of customers:
- Base (usual diesel-electric submarine);
- variant with airindependent installation;
- "Compact", also with airindependent installation, but of less capacity.
Unlike the German boats equipped with fuel elements, the French submarine (the variant with airindepended power installation) is equipped with the MESMA steam turbine of the closed cycle (STCC). At combustion of diesel fuel and oxygen (contained onboard the boat in liquid type) in the special chamber the warm is generated wich serves for work of the steam generator of this PP. Steam goes for supply of the turbine with the capacity of 200 kw, and then it is condensed. Water is repeatedly used in system of the closed cycle, and carbonic gas appearing during fuel burning is thrown out the board. Thus internal pressure in system is so, that gas removal can be carried out at the depth exceeding limiting depth of boat submersion.
Three Pakistan «Agosts» transferred to the customer in 1999-2006 which have an additional compartment with the length of about 10 m with the steam turbine of the closed cycle were the first submarines equipped with plants of MESMA type. Thus standard displacement of the modernised boats increased from 1500 to 1770 t, and the maximum speed reduced from 20 to 19 knots.
The contract for construction of the first "Scorpen" (which were unlike Agost and German Type 212/214 completely export ships) was signed in 1997. It provided construction of two NNSs (O`Higgins and Carrera) in base (diesel-electric) configuration for the Naval Forces of Chile. The transfer to the customer was accordingly in 2007 and 2008. In 2002 another contract for two boats for the Naval Fleet of Malaysia was signed. And in 2003 Spain made the decision on construction of four S-80 NNSs (enlarged in sizes modification of "Scorpen") on Izar shipyard.
However the greatest success of the French builders of submarines was in India. On October, 6, 2005 the contract on licence construction of six "Scorpen" for the Indian Naval Forces was signed as a result of the international competition. The construction (using French accessories) of submarines of base variant as well as the variant with MESMA plant (starting with the fourth hull) on Indian shipyard "Mazagon Docks" (Bombay) is provided. It is supposed, that the first Indian submarine will enter the service in 2012 and the whole series will be finished by 2017.
Unlike the boats of this type intended for Chile and Malaysia which have just torpedo weapons the Indian "Scorpen" NNS should be equipped with the SM.40 Exocet anti-ship tactical cruise missiles launced from undewater.
It is necessary to notice that promption of NNSs on international weapons market is actively lobbied at the top international level by our competitors. In Germany it was the Chancellor who personally performed the promotion of German submarines for export, carried on negotiations with the prime minister and the president of India as well as with the leaders of some other countries. French president Chirac personally went to the president of India, to the prime minister of Malaysia... India and Malaysia bought "Scorpen" instead of our boats. South Korea, Greece and Portugal bought Type 214 boat, Chile bought "Scorpen"... Such tendency is very alarming. But we will return to the French ship.