By Commodore Anil Jai Singh

Vice President, Indian Maritime Foundation

03 December 2018. The recent completion of the first ever deterrence patrol by India’s indigenously built ballistic missile armed nuclear submarine (SSBN), INS Arihant marked an important milestone in India’s quest for great power status. The operationalisation of the sea-based deterrent also completed the nuclear triad since India already had land-based and air-based delivery platforms and thus validated India’s No First use policy which is the cornerstone of India’s nuclear doctrine ever since it was first drafted consequent to the nuclear tests in May 1998.

This achievement was duly recognised by the Prime Minister himself who felicitated the crew of the submarine on 5th November and congratulated all those who have been associated with this programme and sent out a strong message about India’s strategic intent. India is now only the sixth nation with this capability, the others being the five permanent members of the Security Council.

From a maritime security perspective it further reinforced the importance of the submarine as the cutting edge of the country’s offensive maritime capability across the strategic, operational and the tactical domains.

Ever since Sgt Ezra Lee launched the first offensive action by a submarine on HMS Eagle in New York Harbour on 07 September 1776, from his one-man submersible, the “Turtle” built by David Bushnell, the undersea domain has been an important factor in a nation’s maritime security calculus.

In 1904, the legendary British Admiral, Sir “Jacky” Fisher articulated the potential odf the submarine when he said “It is astounding to me, perfectly astounding, how the very best amongst us fail to realise the most impending revolution in naval warfare and naval strategy that the submarine will accomplish.” This revolution in Military Affairs (RMA), to use a more contemporary term, has continued unabated and has played a major role in shaping the course of not only all major global conflicts including the two World Wars but to some extent, influenced the shape of world history itself. In World War I the German declaration of unrestricted submarine warfare changed the very paradigm of naval warfare and added a new dimension to the submarine’s offensive capability. It was in World War 2 that submarines really came into their own. While it was Karl Donitz’ legendary “wolf-packs” in the early years that almost won the war for Germany, it was the Allied submarines that that led to the war ending in a decisive Allied victory.

The Cold War which followed and “raged” for over four decades threatened to erupt into a what would have been a nuclear Armageddon on numerous occasions. It was the submarines of both the protagonists that once again that provided the vital deterrence and ensured that the Cold war remained “cold” despite many provocations. The cat-and-mouse games played out between the nuclear submarines of both sides deep in the ocean depths and below the polar ice caps came to, infact, characterise the Cold war itself.

The undersea domain was not only about submarines. Anti-submarine technologies were also being developed simultaneously and it was the development of these that went a long way in blunting the submarine edge and countered their offensive. The development of ASDIC in World war I and the advent of sonar and radar in World war 2, the Cold war era SOSUS and SURTASS networks, the improvements in Air ASW and the evolution in weapons from depth charges to smart torpedoes has further intensified the lethality of undersea warfare.

When the Cold War ended with the disintegration of the Soviet Union in 1991, there was a perception that ASW would lose its importance. However, with the maritime focus shifting to the littoral, many more countries are now investing in both, submarines and ASW technologies to counter the submarine threat.

At the strategic level, the big Five powers – USA, Russia, UK, France and China are developing newer and better SSBNs as strategic deterrence remains core to the articulation of their national interest.  A credible and invulnerable second-strike capability will remain integral to the exercise of strategic power for which the submarine is the ideal platform. India is now the latest entrant tot his exclusive club.

At the operational level, the ability to shape a favourable battlespace will drive submarine capability. The nuclear attack submarine (SSN), with its high precision weapons including land-attack missiles, limitless high-speed endurance and inherent stealth is the ideal platform. At the tactical level, in littoral waters, the conventional diesel-electric submarine (SSK) will remain the preferred choice of many regional navies because of its smaller size, better stealth characteristics and ability to exercise effective sea denial and under certain circumstances, perhaps even limited sea-control with their improved capabilities and sophisticated technologies including standoff weapons, advanced sensors and Air Independent Propulsion.

The undersea warfare dimension forms an integral and important part of every maritime nation’s security landscape.  The extent of its commitment depends on the threat perception, the geopolitical imperatives shaping the region and to a considerable extent, its economic and military strength.  It can range from the non-glamorous and low-cost, albeit effective mine warfare at the lower end to the other extreme of strategic ballistic missile submarines.  Add to this, the elements required to counter these threats and the underwater battle space thus encompasses all the five dimensions viz., sub-surface, surface, air and to a lesser extent presently, space and cyberspace. As bilateral and multilateral flashpoints continue to flare up and delineation of maritime boundaries becomes increasingly contentious, the undersea dimension’s importance is also increasing.

In the 21st century the global geopolitical centre of gravity has shifted eastwards to what is now acknowledged as a single strategic entity called the Indo-Pacific, and which, as the very name suggests, has a maritime orientation and its own fair share of conflicting challenges.  This was very aptly described by Dr John Chipman, the Director General of the IISS in his address at the 2014 Shangri-la Dialogue who said “The Asia-Pacific, or the Indo-Pacific, as it is sometimes called is a geo-politically highly charged area. It is a place where strategic swagger mixes with diplomatic caution; where solemn proclamations of principle intermingle with selective breaches of norms. It is a region where military modernisation invites an action-reaction dynamic that operates without the constraint of formal arms control arrangements or the calming comforts of established confidence building measures. It is a place where regional institutions abound, and national competition remains fierce. There is domestic instability, international tension and suspicion, and all the while, the highest priority put on continuing the Asian economic miracle that could bring so much prosperity to people here and indeed across the globe.”

The emergence of China and India as potential great powers, the Chinese maritime resurgence, the US rebalance to the Asia-Pacific region, the West Asian cauldron and the vulnerabilities of numerous small states in the Indo-Pacific has created an unstable and uncertain maritime environment. This has led to nations reviewing their maritime security architecture and reorienting their force structure accordingly.

While countries like China and India are seeking sea control capability centred around Carrier Battle Groups, and strategic ascendancy through strategic and attack submarines, smaller countries are aspiring to an effective sea denial capability which is essentially a submarine – centric strategy. Ensuring the safety of their vital economic interests and territorial integrity would be uppermost in the minds of the smaller countries who would structure their forces at blunting a superior offensive. That perhaps explains the submarine force build-up in the region.

The Indo-Pacific countries operate over 150 submarines between them.  In the context of current littoral warfare, stand-off weapon delivery from sea borne platforms precludes the requirement of surface fleets or even SSNs to close land for delivering their lethal ordnance. Modern SSKs are very well suited for choke point deployment as well as open ocean deployment to intercept and interdict the enemy.

Naval force development is aimed at operating an optimum force capable of delivering maximum effect across the entire spectrum of conflict.  Submarines have this ability to operate and operate across strategic, operational and tactical domains, some of which include the following :-


  1. a) High Speed & Long Endurance at sea.
  2. b) Ability to deliver ordnance at stand-off ranges.
  3. d) Shallow water operation capability
  4. e) Second Strike capability
  5. f) Surveillance and Reconnaissance capability
  6. g) Clandestine and Special Operations capability
  7. h) Effect maritime manoeuvre and speedy redeployment
  8. j) Over-the-Horizon Targeting


The Indian Navy presently has 14 conventional submarines in commission and one SSN, INS Chakra, an Akula-II class SSN on lease from Russia and INS Arihant which has a strategic role. Of the 14 SSKs, 12 are more than 25 years old and one is 18 years old. Five more SSKs will join the navy over the next five years and six of the older ones are being modernised. This will provide some reprieve from impending obsolescence till the planned 12 SSKs and six SSNs enter service but the lack of urgency seen presently is something we can ill-afford.

Six of the world’s 10 nuclear powers are located in the Indo-Pacific, some of whom view nuclear capability as an existential necessity while yet others have clandestine programmes. The non-proliferation record of some of these is questionable and very evident including those that have a place on the global top table. The rhetoric that emanates is often aggressive and raises concerns on the inherent instability this brings to the region. For countries such as India with a clearly enunciated ‘No First Use’ doctrine, the importance of an invulnerable second strike is critical and hence the importance of the SSBN in our undersea security construct.

Detection ranges underwater a determined by the existing hydrological conditions and in our waters these are inherently favourable to submarine operations. Submarines have the advantage of choosing an optimum operating depth to avoid detection or when the need arises to deliver an attack.  This could be done either to escape detection by the ASW platforms or attack them with a substantial range advantage to gain the tactical edge. Imagine a scenario in which a submarine fires a salvo of torpedoes which travel at over 50 miles per hour below the surface at a group of ships while simultaneously targeting two or more ships. With a reaction time perhaps of less than three minutes to detect and to evade the torpedo either by manoeuvring and launching a counter attack or even attempting to seduce the torpedo away, the options to avoid being hit are rather limited.

There is a perception that surface ships, despite their Anti-submarine warfare capability are extremely vulnerable to submarine attack. There is no doubt that a surface platform is at a disadvantage vis-à-vis a submarine in the warm and saline waters where we operate. The range advantage that submarines enjoy in detection of noisy surface platforms provides a tremendous tactical advantage for a submarine to manoeuvre itself into a favourable position either for attack or for evasion and as the tactical situation demands. However, the effect that a concentrated surface force or a Search and Attack Unit (SAU) can bring to bear on a submarine once it is detected can make the submarine position extremely vulnerable besides allowing the main body to sidestep the threat. The advancements in technology with active towed array and Variable depth sonars which can be lowered to the same depth that the submarine is operation at have reduced the submarine’s advantage to some extent. Multi-static sonars on board ships and the advent of network centric warfare has further increased the vulnerability of submarines, particularly conventional submarines which have to breach the surface to charge their batteries, thus exposing snorkel and periscope (with ESM) masts to detection for this duration, however short it may be. While Air Independent Propulsion (AIP) mitigated this vulnerability to a large extent, the limitation still remains.

The Indian Navy has a balanced blue water surface force which is designed to counter the submarine threat. The Delhi, Kolkatta and older Kashin class destroyers together with the Talwar, Shivalik and Brahmaputra class frigates and the newly commissioned Kamorta class ASW corvettes give the IN a formidable ASW capability. The Navy is finalising its plans to acquire 16 ASW Shallow Water craft of about 750 tons. These will be equipped with a Hull Mounted Sonar and a Low Frequency Variable Depth Sonar (LFVDS). Small and efficient surface platforms with a modern ASW suite can be an asset for small navies operating in the shallow littorals and in restricted oceanic spaces. ASW weapons are also benefiting from technology. At the recently concluded MAST Indo-Asia Conference near Delhi, the latest Sea Hake Mod 4 Extended Range Torpedo developed by the German firm Atlas Elektronik GmbH elicited considerable interest. Fired from surface ship with a range in excess of 140 kms which is unprecedented thus far, it uses way points and GPS inputs to home on to its target. Imagine an unsuspecting submarine lurking well outside any existing ASW weapon’s range suddenly being set upon by a torpedo. Even if it were to successfully evade the torpedo by effecting a TCM, its position would be compromised for subsequent attacks by a SAU or other ASW forces

One of the major weaknesses of surface ASW forces is their inability to evade a torpedo attack even though there are promulgated Torpedo Counter Measures (TCM) against modern submarine torpedoes. This is the great advantage submarines have because even though their position is compromised once they have fired a torpedo, they do not expect immediate retribution and therefore get time to effect an evasive manoeuvre and get away from the scene.  Hard kill measures against torpedoes are now being considered to destroy an incoming torpedo.

Submarines are vulnerable to detection from the air buy Long Range Maritime Patrol(LRMP) Aircraft and ASW helicopters. The ability of an ASW helicopter to hover in the air and lower its sonar body in a random cycle in both passive and active modes can confuse a submarine even if it is aware of the presence of a helicopter.  Similarly, LRMP ASW aircraft such pose a serious threat as their Time on Task enables a concentrated patrol capability with its combination of sonobuoys, radar, Magnetic Anomaly Detector (MAD) and weapons. This puts considerable pressure on a submarine operating in hostile waters in a potential combat scenario.

The Indian Navy’s LRMP capability has received a tremendous boost with the induction of the Boeing P8I aircraft.  However, the delay in replacing and augmenting the ship borne ASW helicopter fleet is a matter of serious concern. The likely induction of 24 Sikorsky MR-60 helicopters from the USA will alleviate this somewhat.

The evolution of submarine and anti-submarine warfare is a continuum that will be shaped by the dynamics of the maritime battle-space and the relentless march of technology. In the Indo-Pacific the importance of undersea warfare set to increase as nations continue to develop their maritime capability. The Indian Navy has to focus its attention on a multi-dimensional undersea warfare construct commensurate with its status as the pre-eminent power in the region and to counter any aggressive intent.