India's nuclear doctrine commits the nation to No First Use of nuclear weapons and a credible minimum nuclear deterrence. Traditionally, credible nuclear deterrence is built around a nuclear triad comprising ground based nuclear missiles, submarine based nuclear missiles, and air delivered nuclear weapons.

India is striving to acquire a nuclear triad, but currently its triad has just one leg - Ground based nuclear missile. (India's airborne nuclear deterrent lacks credibility because it entails penetration of heavily contested airspace by fighter bomber aircraft, followed by highly inaccurate toss / glide bombing!)

A deterrence triad provides a hedge against game changing technological breakthroughs by the adversary. For example, if it becomes possible to detect submerged submarines using space based sensors then the undersea leg of a nuclear triad would be compromised.

Lessons from Russia's Tu-160 Revival Program

It was recently reported that Russia has decided to revive production of its Soviet era Tu-160 'Blackjack' bomber.

The Tu-160 is a supersonic, variable-sweep wing, heavy strategic bomber/missile carrier that entered service in 1987. Regular production of the aircraft was stopped in 1992 following the unravelling of the Soviet Union. A total of 35 aircraft were built.

The Russian Air Force (VVS) currently has 16 Tu-160 bombers in service. These are being upgraded to Tu-160M standard, as announced in 2012. To cover the cost of reviving production, Russia may build an additional 50 aircraft, or more.

The Tu-160 was originally designed to carry 12 Kh-55 cruise missiles with thermonuclear warheads. Now the aircraft is armed with the technologically more advanced Kh-101 and Kh-555 missiles with 5-m accuracy.

Russia wants to revive Tu-160 production because it believes US ballistic missile defense (BMD) capability has reached a technological maturity level where it could compromise Russia's nuclear deterrent based on ground and submarine launched ballistic missiles.

During 1990s and 2000s, Russia focused on developing mobile missile system at the cost of its airborne deterrent. It's now being forced to make amends for the neglect of its bomber fleet!

Indian Land Based Nuclear Deterrent

Land based nuclear deterrent is the cheapest of the triad, to build and maintain. Mobility and containerization make land based missiles difficult to target in a preemptive counterforce strike. With its limited defense spending, India has focused on building this leg of the triad so far.

Meanwhile, China has been developing its BMD capabilities. Having acquired limited BMD capability through the purchase of the Russian S-300 system, China is now developing a more comprehensive BMD system based on kinetic interception of adversary missiles, in space (exo-atmospheric) and within the earth's atmosphere (endo-atmospheric).

According to the US DoD's 2015 report to congress, China tested a ground-based, midcourse interceptor in January 2010 with a follow-up test in January 2013. Both tests were reported to be successful and a professor at Second Artillery Force Engineering Institute claimed, “The success of this missile defense test means that China has already successfully resolved the issues of upper atmosphere target identification, tracking, and terminal guidance issues and that its mid-course missile defense technology is at the forefront of world technology.”

Despite the professor's enthusiasm, the US is unlikely to be rattled by current Chinese BMD capability. It will be a while before China acquires the technical competency to field a system that could cope with US electronic attack (EA) and multiple independently targeted reentry vehicle (MIRV) warheads. Also, China has yet to build a space-based early warning system that could detect US missile launches from anywhere around the globe.

However, our concern is about India's missile deterrence. We don't have the EA capability of the US, we don't have MIRV capable missiles as the US does, and the trajectory of our missiles would be easy to predict because of their limited range, facilitating early warning and tracking with in service PLA radars! In other words, China's current BMD is not something that India can afford to ignore.

Submarine Based Deterrent Limitations

The submarine leg of the nuclear triad would be as susceptible to adversary BMD systems as the ground based leg, since both use ballistic missiles.  Also, building a credible submarine based nuclear deterrent is a slow and expensive process that India has just embarked on. It will likely take decades before this leg of the triad becomes credible.

Cruise Missiles

Ballistic missiles largely follow a predictable trajectory, so despite the bullet-hitting-bullet analogy, their warheads can now be destroyed using advanced sensors.

Unlike ballistic missiles, cruise missiles can follow unpredictable trajectories, presenting an effective and possibly more potent deterrent delivery option. However, the overall effectiveness of cruise missiles depends on their speed, stealth, and guidance accuracy. Stealthy Air launched cruise missiles (ALCMs) represent the most effective alternative to ballistic missiles for nuclear weapon delivery.

Credible Airborne Deterrent

The need for India to acquire a credible airborne nuclear deterrent delivered by short to medium range supersonic cruise missiles should be easy for the reader to appreciate by now.

An ALCM wouldn't expose its launch platforms to enemy air defenses, facilitating assured warhead delivery.

A short range ALCM could be command guided to its target from its high flying launch platform, or an AWACS, ensuring pinpoint accuracy without the use of SatNav, making the missile less prone to jamming. A nuclear tipped ALCM doesn't require pinpoint accuracy so it could even use an inertial navigation system which is completely unjammable.

When operating in strategic roles, American and Russian heavy bombers such as B-52, B-1, B-2, Tu-95 and Tu-160, and light bombers such as the Tu-22, Su-24 and Su-34 are equipped with ALCMs, not gravity bombs.

Airborne Deterrent Costs

An airborne deterrent is considerably more expensive to acquire and maintain than a ground based deterrent; it's almost as expensive as a submarine based deterrent. But surely that cannot be the reason for India not having a credible airborne deterrent!

The airborne leg of the triad has a unique advantage over the other two legs - It can be brandished!

In an acute crisis, a country can launch its nuclear bombers on armed patrol within its airspace, forcefully conveying its resolve to the adversary, while keeping its deterrent safe from preemptive nuclear attack.

You cannot similarly brandish your submarine or land based nuclear deterrent to convey your resolve.

Suitable Platform for Airborne Deterrent

A credible airborne deterrent would have to be based on an in production aircraft to ensure long term availability of spares. The IAF would be happiest if the spares could be sourced from within our country.

The US does not sell its bombers, so India would have to source its requirement from Russia, which currently has just the Su-34 light bomber under production.

The Su-34 is a sibling of the IAF's Su-30MKI. Larger and heavier, the twin seat Su-34 has an enlarged front section. It carries more fuel and features a strengthened airframe.  The aircraft is honed to penetrate deep into heavily contested airspace at low levels with crew comfort. It features SEAD electronics and weapons to help deliver its cruise missile payload.

The Su-34 features many of the same major systems as the Su-30MKI, including power plant. The aircraft would be a much more competent delivery platform for the IAF's nuclear deterrent, than the Mirage-2000, Jaguar or Su-30MKI.

If Russia were to resume production of the Tu-160 bomber, the aircraft would present an alternative option. However, it would be a more expensive overkill in terms of capability.

By VK Thakur