INS Aridhaman to be out soon. Here’s what you need to know about nuclear submarines

Later this month, defence minister Nirmala Sitharaman will launch India’s second indigenous nuclear submarine, INS Aridhaman, following which the new vessel will get into service by 2019.

Published: 14th September 2017 04:33 PM  |   Last Updated: 15th September 2017 02:58 PM   |  A+A-

INS Arihant and underwater B-05 missile | Photo courtesy: DRDO

Express News Service

CHENNAI: Later this month, defence minister Nirmala Sitharaman will launch India’s second indigenous nuclear submarine, INS Aridhaman. Following its launch, the new vessel will undergo sea trials and will be inducted into service no later than 2019. 

A nuclear sub is something only a few countries can boast of. In fact, the induction of INS Arihant into service in 2016 made India the only country apart from the five permanent members of the UN Security Council to operate a homemade nuclear U-boat. 

INS Aridhaman will carry twice as many missiles as INS Arihant besides travelling faster under water. It is fitted with eight launch tubes unlike its elder sister Arihant, which has only four. Further, experts say the new sub will carry K-15 and (the newer) K-4 ballistic missiles as does INS Arihant. K-4 is an intermediate range ballistic missile that can hit targets as far as 3500 km. 

Aridhaman’s launch comes at a time of growing tensions in the Indian Ocean region. Analysts say there has been a spike in the Chinese naval presence in the Indian Ocean. Just days after India objected to China’s construction of a road on the Doklam plateau, India Today reported that a Chinese submarine surfaced in the Indian Ocean waters. Although the timing is interesting, it would be a mistake to ignore the larger picture. For quite some time now, China has been ratcheting up its presence in the region. Abhijit Singh, a former naval officer who heads the Maritime Policy Initiative at the New Delhi-based Observer Research Foundation, said, “Since January this year, China has been able to establish a strong military and economic presence in the Indian Ocean region, with many South Asian states bending over backwards to accommodate Beijing’s regional initiatives.”  

Strategic experts warn that China would use its superior naval might to choke India in the Indian Ocean in the event of a conflict. China’s growing trade with countries in Africa and West Asia means that maintaining access to the Indian Ocean is a priority for Beijing. However, there is always a possibility that India and the US, which maintains a significant presence in the Indian Ocean, may see this Chinese naval activity as a threat to their own interests. 

Further, the launch of INS Aridhaman comes just months after China announced the start of the sea trials of its first domestically built aircraft carrier. Locked in competition, New Delhi sees no option but to boost its own capability. One way of doing so is by building its own nuclear sub.

Nuclear vs conventional submarines 

Put simply, nuclear submarines are those that are powered by onboard nuclear reactors. Conventional submarines generate energy by burning diesel, which requires air. The energy is then stored in a battery, which powers the submarine. However, once power runs out, the vessel has to surface again. In contrast, the nuclear reactors on board a nuclear submarine generate heat by splitting Uranium atoms into two in a process called nuclear fission. The heat is then used to boil water to produce the steam which spins the turbine and produce electricity. The electricity thus generated powers the submarine.  Since there is no need for air, nuke submarines can stay underwater for months. Also, they can cruise faster than conventional subs without their battery running out. 

It is clear that a war between India and China is not likely to be limited to their disputed border. China would draw India into a confrontation in the Indian Ocean. As such, it is imperative for India to boost its Sea Control and Area Denial capability.  Nuclear submarines have a vital role to play here. They help the navy retain full command of the sea. Their stealth features enable them to enter waters undetected and carry out surveillance and intelligence gathering activities. For instance, a nuclear submarine can lurk underwater and keep an eye on activities in the waters near the Chinese port of Hambantota in Sri Lanka. They can also be used to attack enemy ships that stray into India’s territorial waters. 

It’s not easy to spot a submarine underwater

Nuclear submarines are a useful tool because they can lurk deep under the sea undetected for months. It is not easy to locate these giant monsters once they plunge deep underwater. Why? Subs ply at the deep end of the ocean. They can lurk quietly for hours making it impossible for passive sonar to detect them. Even if active sonar waves are used, the fact remains that there are rock formations beneath the surface of the ocean. Thus, the sound waves reflected back to the surface may not give an accurate picture of what’s down there. More importantly variations in water temperature and pressure at different levels of the ocean damage the quality of sonar data. Further, surface ships make a lot of noise as they cruise through the waters. This alerts the crew of a submarine who can then take evasive measures before the sound waves are dropped. 

Being hard to detect makes nuclear submarines ideal for carrying nuclear weapons. Strategic experts call this the “sea-basing of nuclear weapons”. This enables a country to retain a second-strike capability in case a first-nuclear strike by the enemy destroys all its land based nukes. “By virtue of its stealth and attendant survivability of second-strike capability, a nuclear submarine is particularly suited for nuclear deterrence,” says India’s Maritime Doctrine, a 2009 report by the Ministry of Defence.


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