July 2, 2009


Analysis of Indian and Pakistani (Future) Diesel Electric Submarines.

The 6 Scorpienes ordered by the Indian Navy has not yet been commisioned but we could analise the capabilities of these key military weapons.

The Indian Option Scorpene Diesel Electric

Scorpene Attack Submarine

Key Data:

Overall Length

Submerged Displacement
Surface Displacement
Pressure Hull Weldable and High-Tensile Steel
80HLES, more than 700Mpa

Maximum Operating Depth
Submerged Speed
Over 20 kt

Range (at 8kt)
50 days

Weapon Systems:
Torpedoes / Missiles
Six 21in torpedo tubes for 18 torpedoes / missiles

The Scorpene submarine has been jointly developed by DCNS of France (formerly DCN) and Navantia (formerly Bazan, then Izar) of Spain. Two Scorpene submarines were ordered by Chile. The vessels replace two Oberon Class submarines which were retired in 1998 and 2003.

The first, O'Higgins, built at DCN shipyard in Cherbourg, was launched in November 2003 and commissioned in September 2005. It arrived in Chile in January 2006. The second, Carrera, built at the Cartagena shipyard of Navantia in Spain was launched in November 2004 and commissioned in July 2006. Carrera arrived at its homeport of Talcahuano in December 2006.

The Royal Malaysian Navy placed a contract for two Scorpene submarines in June 2002. The first vessel, KD Tunku Abdul Rahman, was launched at DCNS Cherbourg in October 2007 and was handed over in January 2009 in Toulon. It is scheduled to arrive in Malaysia in mid-2009.

"The SSK Scorpene attack submarine is equipped with six bow-located 21in torpedo tubes providing salvo launch capability."
The second, Tun Razak, was launched at Navantia Cartagena in October 2008 and is to commission in October 2009. DCNS is building the bow sections, Navantia the aft sections.

In October 2005, India placed an order for six Scorpene submarines. The submarines will be built at the state-owned Mazagon dockyard in Bombay, with technical assistance and equipment from French companies DCN and Thales. At the same time, India also placed an order for 36 MBDA SM-39 Exocet anti-ship missiles to arm the submarines. Construction of the first vessel began in December 2006 and is scheduled to be delivered in December 2012. One submarine will be delivered each year until 2017.

In December 2008, Brazil placed an order for four diesel-electric-powered submarines based on the Scorpene. The submarines will be built by a joint venture company set up by DCNS and Odebrecht of Brazil and will enter service in 2015.
Scorpene for the Chilean Navy

The 1,500t Scorpene built for the Chilean Navy has a length of 66.4m. The two vessels are powered by four diesel generators providing more than 2,500kW using GM synchronous motors with permanent magnets.

The Chilean Scorpene will have a hull-mounted medium-frequency active / passive sonar. The vessels are armed with WASS (Whitehead Alenia Sistemi Subaquei) Black Shark heavyweight torpedoes.
The Black Shark is a dual-purpose, wire-guided torpedo which is fitted with Astra active / passive acoustic head and a multi-target guidance and control unit incorporating a counter-countermeasures system. It has an electrical propulsion system based on a silver oxide and aluminium battery. Black Shark will also arm the two Scorpene vessels for the Royal Malaysian Navy.

The six torpedo tubes will be capable of firing SM-39 Exocet anti-ship missiles, which have a range of 50km, but they will not initially be carried. The vessels will be equipped with EDO Reconnaissance Systems AR-900 electronic support measures/direction-finding (ESM/DF) system.

Weapons systems
Scorpene is equipped with six bow-located 21in torpedo tubes providing salvo launch capability. Positive discharge launching is by an air turbine pump.
"Handling and loading of weapons is automated."
The submarine's weapons include anti-ship and anti-submarine torpedoes and anti-surface missiles.
18 torpedoes and missiles or 30 mines can be carried by the Scorpene attack submarine. The handling and loading of weapons is automated.

SUBTICS combat management system
The SUBTICS combat management system, with up to six multifunction common consoles and a centrally situated tactical table, is collocated with the platform-control facilities.
The combat management system is composed of a command and tactical data handling system, a weapon control system and an integrated suite of acoustic sensors with an interface to a set of air surface detection sensors and to the integrated navigation system. The system can also download data from external sources.
The integrated navigation system combines data from global positioning systems, the log, depth measurement and the ship's trim / list monitoring system. The Scorpene monitors the environment including seawater density and temperature and the submarine's own noise signature.

Sonar suite
The vessel's sonar suite includes a long-range passive cylindrical array, an intercept sonar, active sonar, distributed array, flank array, a high-resolution sonar for mine and obstacle avoidance and a towed array.

Control and monitoring
All submarine handling operations are carried out from the control room. The vessel features a high level of automation and surveillance, with automatic control mode of rudders and propulsion, continuous monitoring of the propulsion systems and platform installations, centralised and continuous surveillance of all potential hazards (leaks, fires, presence of gases) and the status of the installations that affect the safety while submerged.
"The submarine's weapons include anti-ship and anti-submarine torpedoes and anti-surface missiles."

The submarine incorporates a high level of system redundancy to achieve an average 240 days at sea a year for each submarine. The maximum diving depth is 300m, giving the commander more tactical freedom than previously available on conventional submarines. There is no limit to the duration of dives at a maximum depth, other than the power systems and crew limitations.
The structure of the submarine uses high-yield stress-specific steel which allows for as many dives to maximum depth as necessary.

The use of high-tensile steels has reduced the weight of the pressure hull, allowing a larger load of fuel and ammunition. The reduced complement minimises training costs and increase combat efficiency by making more space, while a larger payload enhances the ship's autonomy.
When dived the Scorpene has low radiated noise which permits improved detection ranges of its own sensors and reduced risk of detection by hostile sensors. The low radiated noise is achieved through the use of advanced hydrodynamics with an albacore bow shape, with fewer appendages and an optimised propeller.
Between the suspended decks, the equipment is mounted on elastic mountings wherever possible, and the noisiest systems have a double-elastic mounting to reduce the risk of their noise profiles being radiated outside the submarine. The shock-resistant systems have been developed from systems incorporated in advanced nuclear-powered submarine designs.
The low acoustic signature and hydrodynamic shock resistance give the Scorpene class the capability to carry out anti-submarine and anti-surface ship warfare operations in closed or open sea conditions, as well as the capability of working with special forces in coastal waters.

Crew facilities
The ship can hold a total company of 31 men with a standard watch team of nine. The control room and the living quarters are mounted on an elastically supported and acoustically isolated floating platform. All living and operational areas are air-conditioned. The submarine also has space for six additional fold-down bunks for special operations crew.
"The ship can hold a total company of 31 men with a standard watch team of nine."
The vessel is equipped with all the necessary systems to provide vital supplies, water, provisions, regeneration of the atmosphere, to ensure the survival of all the crew for seven days.
The ship is equipped with full rescue and safety systems. A connection point for a diving bell or deep submergence rescue vehicle (DSRV) allows collective rescue operations.

Stealth design
The planning and design of the Scorpene was directed towards achieving an extremely quiet vessel with a great detection capability and offensive power.
The forms of the hull, the sail and the appendages have been specifically designed to produce minimum hydrodynamic noise. The various items of equipment are mounted on elastic supports, which are in turn mounted on uncoupled blocks and suspended platforms. The isolation also provides better shock protection to the equipment.

Propulsion systems
The Scorpene has two diesel generation sets providing 1,250kW of power. At the top of the hull immediately above the diesel generator sets is a Dutch Breach machinery shipping hatch. The submarine has an elastically supported 2,900kW electronic engine.
There are two variants of Scorpene, the CM-2000 with the conventional propulsion system and the AM-2000 equipped with air independent propulsion. The AM-2000 is capable of remaining submerged on underwater patrol for three times longer than the CM-2000.

Air independent propulsion
A conventional diesel-electrical submarine sailing underwater is difficult to detect. However the need to come repeatedly to periscope depth to recharge the batteries using the diesel engine greatly increases vulnerability by:
Its aerial detectability, since the snorkel projecting from the water is detectable by radar
Its underwater detectability due to increase in radiated noise from the working diesels
The ratio between this time of greater vulnerability and the total operating time is known as the "indiscretion rate" and for all conventional modem submarines the indiscretion ratio ranges typically from 7% to 10% on patrol at 4kt, and 20% to 30% in transit at about 8kt.
"To lessen the submarine's vulnerability, Scorpene can be equipped with an air independent propulsion system."
To lessen the submarine's vulnerability, the vessel can be equipped with an air independent propulsion system such as: the Stirling engine, the fuel cell, the closed circuit diesel and the module d'energie sous-marine autonome (MESMA) system .
The MESMA anaerobic system, in which heat in the primary circuit is produced by burning ethanol with oxygen, can be easily installed either at the start of the submarine's construction or in a later modernisation to convert the CM-2000 to an AM-2000 build standard.
With the MESMA system the AM-2000 submarine can stay down on underwater patrol three times longer than the CM-2000.
Its performance features remain the same in all other respects, except that the length increases to 70m and its submerged displacement to 1.870t (against the 61.7m and the 1,565t of the CM2000).

The Pakistani option U 214 Diesel Electric

The Agosta 90 B class of Diesel attack submarine (Pakistani Navy has three submarines of this class, and is trying to upgrade the existing ones to the latest versions. Pakistan is also trying to procure Geerman Submarines. But has not yet materialised.)

U214 Attack Submarines, Germany

Key Data:

27 (including five officers)

Weapon Systems:
six 533mm tubes, 24 STN Atlas Elektronik DM2A4 torpedoes
Combat Data Syetem
Basic Command and Weapons Control System (BCWCS)
TAU 2000 torpedo countermeasures system
Kelvin hughes type 1007 I-band navigation radar
STN Atlas Elektronik DBQS-40 sonar suite and STN Atlas Elektronik MOA 3070 mine detection sonar
Zeiss Optronic SERO 14 search and SERO 15 attack

Diesel-electric, MTU 16V-396 diesel engine, 3.12MW, HDW / Siemens AIP (Air-Independent Propulsion) system, 300kW

U214 Dimensions:

Surface Displacement
Presure Hull Diameter
Buoyancy Reserve

U214 Performance:
Submerged Patrol Speed of Advance
Mission Endurance
12 weeks
Constantly Submerged
Three weeks without snorkelling
Mission Sprint Speed
15kt to 20kt
Maximum Dive Depth

HDW has developed the Type 214 submarine, which is a further improvement on the Type 212.

The Greek Navy has ordered three Type 214 submarines. The first, Papanikolis (S120), was built at the HDW Kiel shipyard and was launched in April 2004. As of April 2008, the Greek government has refused to accept delivery of the vessel and a commissioning date is uncertain. The vessel successfully completed a further series of sea trials in September 2008.

The Hellenic Shipyards is building the second (Pipinos S121, launched November 2006) and third (Matrozos 122) vessels at Skaramanga. Hellenic Shipyards was acquired by HDW (now part of ThyssenKrupp Marine Systems) in May 2002. A fourth vessel, Katsonis (S123) was ordered by Greece in June 2002 and is expected to commission in 2012.

South Korea has also ordered three Type 214, to enter service in 2007, 2008 and 2009. These are being built by Hyundai Heavy Industries. The first, Admiral Sohn Won-il, was launched in June 2006 and commissioned in December 2007. The second, Jung Ji, was launched in June 2007 and is to be delivered in November 2008. The third, Ahn Jung-geun, was launched in June 2008 and will be commissioned in November 2009. The submarines will form the KSS2 Class. An additional three submarines may be ordered.

The Type 214 will have an increased diving depth of over 400m, due to improvements in the pressure hull materials. Hull length is 65m and displacement 1,700t. Four of the eight torpedo tubes will be capable of firing missiles.

Type 214 submarines for the Hellenic Navy will be armed with the WASS (Whitehead Alenia Sistemi Subaquei) Black Shark heavyweight torpedo. The Black Shark is a dual-purpose, wire-guided torpedo which is fitted with Astra active / passive acoustic head and a multi-target guidance and control unit incorporating a counter-countermeasures system. It has an electrical propulsion system based on a silver oxide and aluminium battery.

"The Type 214 will have an increased diving depth of over 400m."

Performance of the AIP system has been increased with two Siemens PEM fuel cells which produce 120kW per module and will give the submarine an underwater endurance of two weeks.

A hull shape which has been further optimised for hydrodynamic and stealth characteristics and a low-noise propeller combine to decrease the submarine's acoustic signature.

The integrated sensor underwater system ISUS 90, from ATLAS Elektronik integrates all sensors, command and control functions on board the submarine. BAE Systems provides the link 11 tactical data link. The sensor suite of the U214 submarine consists of the sonar systems, an attack periscope and an optronic mast. The submarine's electronic support measures system and global positioning system sensors are also installed on the optronic mast.

According to my knowledge. Pakistan has plans to buy three of these ships and negotiations have reached 95% according to German sources. But have not pushed in any orders.Pakistani Navy sees the 214 a worthy adversory to the Scorpiens. France is tryin to lobby beaurocrats (bribing them) to opt a French submarine design. We have to wait and see, which ship Pakistan is going to choose.

Sidharth K Menon


Naval Technology (SPG Media)