The Scorpene leaks

As the Indian Navy (IN) prepares for Golden Jubilee celebrations next year to commemorate induction of its first submarine in 1967, it was struck by a story in an Australian newspaper which disclosed that 22,400 pages of documents pertaining to its Scorpene submarine programme, code named Project-75, had been leaked. This has caused quite a stir in defence circles around the globe and raised many pertinent questions related to management of major projects in increasingly technical environments. 

India contracted six submarines of this class from French manufacturer Direction des Constructions Navales Services (DCNS) in 1999 for $3.5 billion under which it was required to provide design and technology to the public sector Mazagon Docks at Mumbai, with an option to build six more. India is expecting to complete sea trials of the second submarine nine months later and induct it in service by end of 2017. The hulls of the remaining four submarines have been cast with plans to complete the program by the year 2020. The programme has lagged behind by many years as submarines of this type in most other navies which were contracted around the same time are nearing mid-life major refits.   

The disclosure of sensitive information spanning over 22,400 pages is a gushing leak by any standards and covers many areas. The newspaper has claimed to be in possession of ten types of secret information which compromises the project and includes stealth capabilities of Scorpene class submarines, its various intelligence gathering frequencies, noise levels at different speeds, diving depths, range and endurance, magnetic, electromagnetic and Infra-red data, specifications of torpedo launch system, and combat system, speed and conditions for use of periscope, propeller noise specifications, radiated noise on surface and weapons data.

DCNS and the Indian Navy have both acknowledged that data has been leaked and have pointed fingers at their competitors. DCNS won a lucrative US$38 billion Australian contract (the largest single undertaking in the country’s history) for construction of 12 Short Fin Barracuda Block 1A type submarines which is a diesel-electric derivative of DCNS’s Barracuda class nuclear attack submarines in service with the French Navy.

The French government has 64 percent stakes in DCNS while the remaining shares are held by various commercial and private firms. There is now a growing trend among submarine operating navies all over the world to prefer customisation of their boats for reasons of cost and performance. In a complex project like submarine construction, where information pertaining to platform has to be exchanged for integration purposes, this carries significant risks for leakage of sensitive information as probably has happened in this case and therein lie some lessons to be learnt.

The secret stealth capabilities mentioned in the leaks pertain to the acoustic signatures of Scorpene submarine and are determined by such inputs as its self-noise level, propeller configuration, underwater speed regime, noise generated by onboard machinery and acoustic dampening techniques employed both inside the submarine and on the hull. The harmonics of a submarine are not a constant. They vary from vessel to vessel and change after every major refit, so the figures have to be measured afresh with special equipment on different occasions. 

Like all diesel-electric submarines, Scorpene needs to come to periscope depth at least once in 24 every hours to recharge its batteries using diesel engines which increases risks of detection of its snorkel by aerial surveillance and increased radiated noise levels of diesel engines can be picked up by sonar arrays. The ratio between time of vulnerability and total operating time is around 10 percent for conventional submarines.

To stay underwater for longer periods and lessen its vulnerability, Scorpene submarines, like Pakistan Navy Agosta 90-Bs, can be equipped with an air independent propulsion system (AIP) but it increases the length of the vessel by eight meters and tonnage by nearly 300 tons. The Indian Navy has planned this modification for fifth and sixth construction and is considering an indigenous system developed by the Defence Research and Development Organization (DRDO).  

The Scorpene submarines are known to be quieter due to different hull construction and placement of onboard machinery according to the methodology used in nuclear submarines. The redacted noise data in the leaks is a function of submarine speed.  Navies spell out decibel limits for noise at various speeds to the manufacturer as an important requirement.

Knowing how much noise a submarine makes underwater and on what frequencies,can be very advantageous tactically. The kind of information contained in these leaks has been described by some experts as the ‘stuff of a navy’s nightmare’. India’s claim of its ability to ‘tweak the fundamentals of designs’ in complex constructions like submarine appear exaggerated. 

The data about propeller noise is generic but serves as a good reference. Once in operation, every propeller generates its own harmonics of noise at different speeds and depths and varying bathy conditions. The Scorpene submarines are fitted with ‘cavitation meters’ to measure noise level to help ascertain most suitable profile for silent loitering. Noise management, however, loses its significance in a hot tactical situation requiring timely positioning for an attack.

The information pertaining to Electromagnetic Support Measures (ESM) is not new as it is standard in most parts of the world. In any case it would be a death knell for a submarine to transmit on any of its emitters in war – complete silence is practised all the time during peace time.   

The information on electromagnetic and infra-red would also serve as a good base reference though the Indian Navy has an underwater demagnetisation range at Goa; the leaked figures would almost certainly change after demagnetisation. The Pakistan Navy has extensive experience of MAD (magnetic anomaly detector) runs by its LRMP (long range maritime patrol) aircraft over submarine probability areas and it should be an interesting contest when the Indian Scorpene starts exercising in the Indian Ocean.  

India has procured 36 MBDA SM-39 Exocet anti-ship missiles to arm its Scorpene submarines (six for each unit). It is launched from a torpedo tube in a water-tight launcher capsule.

This weapons system, designed to attack small to medium size warships, has been in use with Pakistan Navy for years. The leaked data is interesting since it reflects the number of targets the missile is capable of processing, its launch details and how many targets can be downloaded by its submarine tactical integration combat system (SUBTICS) before firing. This is something which should be genuinely worrisome for India.  Interestingly it contradicts the Indian defence minister’s earlier statement that no weapons system details were revealed. The good news for India however is that ‘source code’ of SUBTICS has not been compromised or at least not yet leaked if it has been.

The Exocet causes extensive superstructure damage to a warship and can knock it off operation, but rarely sinks it. On the other hand, a ship hit by an underwater torpedo containing much larger quantity of explosives, rarely survives the attack. India cancelled procurement of Black Shark anti-torpedo for its Scorpene submarines from Italian firm WASS after a VVIP helicopter bribery scandal surfaced. From an intelligence point of view, as and when it selects a new torpedo and integrates it with SUBTICS only then would the ‘loaded’ specifications of its combat system be useful. 

Without a torpedo as its main anti-ship weapon, a submarine might as well be the Beatles version of the ‘Yellow submarine’. But this is certainly not to suggest any complacency. At 22,400 pages, the sheer volume of Scorpene submarines leaks is so huge that a thorough scrutiny is an absolute imperative.

The writer is a retired vice admiral.Email: tajkhattak@ymail.com