issue No 12,
  Published by Dar Assayad Arab Defence Journal
Highlights   المعلوماتية العسكرية تكنولوجيا الدفاع حول العالم العالم العربي تحديث السلاح الافتتاحية رسالة الناشر
Submarines are the ultimate "stealth" naval vessel able to operate out of sight and launch surprise attacks on enemy surface vessels or approach enemy shores unseen on covert reconnaissance mission.

For much of the 20th Century the submarine was the dominant naval weapon system because of their role as the launch platforms for nuclear tipped ballistic missiles. These doomsday machines kept the peace in the Cold War but after the demise of the Soviet Union many nations looked to new technology to reinvigorate their fleets of diesel powered submarines. There revamped diesel boats provided many of the advances features of nuclear powered submarines in terms of speed, stealth, sensor performance and weapons but they cost only a fraction of the price of nuclear boats.
The effectiveness of diesel or conventionally powered submarines has been dramatically enhanced over the past 30 years by the development of highly efficient air-independent propulsion (AIP) system, based around advanced batteries and electrical power systems.
The German Type 212 class submarine, which is also known as the Italian Todaro class, is one of the market leaders at the moment. It is a highly advanced design of non-nuclear submarine developed by Howaldtswerke-Deutsche Werft AG (HDW) for the German and Italian navies. It features diesel propulsion and an additional air-independent propulsion (AIP) system using Siemens proton exchange membrane (PEM) compressed hydrogen fuel cells.
Partly owing to the "X" arrangement of the stern planes, the Type 212 is capable of operating in as little as 17 metres of water, allowing it to come much closer to shore than most contemporary submarines. This gives it an advantage in covert operations, as Scuba-equipped commandos operating from the boat can surface close to the beach and executes their mission more quickly and with less effort.
The Type 212A is capable of launching the fiber optic-guided DM2A4 Seehecht ("Seahake") heavyweight torpedoes, the WASS BlackShark torpedoes and short-range missiles from its six torpedo tubes, which use water ram expulsion system. Future capability may include tube-launched land attack cruise missiles.
The short-range missile IDAS (based on the IRIS-T missile), primarily intended for use against air threats as well as small or medium-sized sea- or near land targets, is currently being developed by Diehl BGT Defence to be fired from Type 212"s torpedo tubes.
The Type 214 is a diesel-electric submarine developed by Howaldtswerke-Deutsche Werft GmbH (HDW), which features diesel propulsion with an air-independent propulsion (AIP) system using Siemens polymer electrolyte membrane (PEM) hydrogen fuel cells. This submarine is derived from the Type 212, but as an export variant it lacks some of the classified technologies of its smaller predecessor.
Russia"s contender in the global submarine market is the latest variant of the Project 636 or Kilo class diesel-electric attack boat. The improved Kilo or Project 636.3 Varshavyanka is the latest variant, which recently saw action off Syria firing Kalibr land attack cruise missiles.
These attack submarines are mainly intended for anti-shipping and anti-submarine operations in relatively shallow waters. The newer Project 636.3 boats are equipped with improved MGK-400EM sonar and the MG-519EM mine detection and avoidance sonar. The improved sonar systems have reduced the number of operators needed by sharing the same console via automation.
Project 677 or Lada class is the new advanced class of diesel-electric attack submarine designed by the Russian Rubin Design Bureau. This is a programme to develop a "fourth generation" diesel-electric submarine; it aimed at producing a highly improved version of the Project 636 Kilo class with much quieter, new combat systems, and possibly air-independent propulsion.
However, in November 2011 the Russian Navy decided that this class of submarines would not be accepted into service, as the lead boat had fallen far short of requirements during tests. The lead boat was retained as a test vessel to experiment with various systems. The construction of the remaining boats of the class was frozen.
In July 2012, the Russian Navy commander-in-chief announced the resumption of the construction of the Lada-class submarines, having undergone extensive design changes. In 2013 and 2015, two further boats were re-laid and commissioning was expected in 2017 and 2018.
The first serial diesel-electric submarine of the Lada class is planned to be launched at the "Admiralteiskie Verfi" shipyard in St. Petersburg in 2018. In June 2017, the Russian Navy revealed it plans to order two more Lada-class submarines.
The Scorpène-class submarines are a class of diesel-electric attack submarines which were jointly developed by the French Direction des Constructions Navales (DCN) and the Spanish company Navantia. The successor to DCN, the Naval Group now markets the submarines. It features diesel propulsion and additional air-independent propulsion (AIP).
The Scorpène class of submarines has four subtypes: the CM-2000 conventional diesel-electric version, the AM-2000 AIP derivative, the downsized CA-2000 coastal submarine, and the enlarged S-BR for the Brazilian Navy, without AIP. The Chilean and Malaysian boats are fitted with the TSM 2233 Mk 2 sonar. The class can also be fitted with an "S-Cube" sonar suite from Thales.
The French Module d"Energie Sous-Marine Autonome (MESMA) system is being offered by the Naval Group for the Scorpène-class submarines. It is essentially a modified version of their nuclear propulsion system with heat being generated by ethanol and oxygen. The combustion of the ethanol and stored oxygen, at a pressure of 60 atm (6.1 MPa), generates steam which powers a conventional turbine power plant. This pressure-firing allows exhaust carbon dioxide to be expelled overboard at any depth without an exhaust compressor.
The land attack potential of diesel powered submarines was graphically demonstrated after Russian Kilo-class boats fired cruise missiles at Syria in 2016. Previously, only British and American nuclear-powered submarines had fired cruise missiles in anger.
However, diesel powered submarines still lack the range and endurance of their nuclear powered counter-parts, which can remain submerged for several months at a time. But nuclear submarines need to be supported by the large engineering and safety infra-structure required to handle their unique fuel needs, which comes with a huge costs. This is the crucial cost-performance tradeoff between nuclear and conventional powered submarines. For many nations diesel submarines are good enough to meet their requirements and deliver many highly effective capabilities.

المواضيع الاكثر قراءة
Submarines are the ultimate "stealth" naval vessel able to operate out of sight and launch surprise attacks on enemy surface vessels or approach enemy shores unseen on covert reconnaissance mission.
<< read more