Source : Indian Defence Analysis
|Arihant class SSBN details by Naval News, Covert Shores|
India is surrounded by heavily Nuclear Armed nations driven by authoritarian government. China and Pakistan have extensive military cooperation at various level including weapons of mass destruction which further complicates the national security of India. This forces India towards having a credible nuclear deterrence where the Nuclear powered Ballistic missile submarines, SSBNs gives India a robust nuclear deterrence capability. Unlike, the ground based ballistic missile system, the SSBNs are least vulnerable, difficult to locate and most survivable deterrence platform. SSBNs will enable Indian Navy to maintain continuous at-sea deterrence or CASD posture.
India’s ATV or Advanced Technology Vessel project is considered as a most secretive and costly defense project till date. Under this India has planned to build 4 Nuclear ballistic missile capable submarine called SSBNs estimated at 90,000 crore rupees. Each of these submarines costs upwards of 4000 crore rupees. These SSBNs are Arihant(S2), Arighat(S3), S4 and S4*. The construction, commissioning, testing and status of the SSBNs are directly under the Strategic Forces Command (SFC) or the Strategic Nuclear Command (SNC), which is under the control of the PMO (Prime Minister’s Office).
INS Arihant(S2): 1st SSBN of India
INS Arihant is India’s first indigenous nuclear powered ballistic missile capable submarine in service. Its design is based on the Akula-1 class submarines of Russia. The submarine has displacement of 6,000 tonnes powered by an 83 MW pressurised water reactor. It can achieve a maximum speed of 12–15 knots (22–28 km/h) when surfaced and 24 knots (44 km/h) when submerged.
India has developed a range of ‘K’ family SLBMs, long-range missiles that can be launched from submarines. The submarines have four launch tubes where it can carry up to twelve K-15 Sagarika missiles with a range of 750 km or four K-4 missiles with a range of 3,500 km.
On 14th October 2022, The Ministry of Defence announced the successfully launched a nuclear capable Submarine Launched Ballistic Missile (SLBM) in the Bay of Bengal with “very high accuracy” from INS Arihant.
The submarine’s K-15 missiles can reach most of Pakistan and it’s K-4 can target all of Pakistan. If deployed in Bay of Bengal, K-4 can reach upto Beijing.
|Image Credit : Indian Defence Analysis|
Arighat(S3): 2nd SSBN of Arihant Class
Arighat is the 2nd & upgraded Nuclear powered ballistic missile submarine built under ATV (Advance Technology Vessel) program. The submarine was launched quietly in 2017 and is nearing the completion of its sea trial. It is expected to expected to enter service with the Strategic Forces Command in 2023. The submarine has displacement and weapons carrying capability similar to INS Arihant.
S4 and S4*: Bigger SSBN
The upgraded S4 & S4* class submarines will have a higher displacement of 7000 tonnes. The S4 – and subsequent boats – are labelled as ‘Arihant-stretch’ variants having 8 launch tubes. It can carry 24 X K15 SLBM or 8 K-4 SLBM – almost double in terms of fire power when compared with Arihant.
The third of the Arihant-class SSBN (Sub Surface Ballistic Nuclear) submarine code-named S4, was quietly launched some time in the last week of November 2021 in Visakhapatnam. The soft launch of S4 was first reported by UK-based Janes Defence Weekly
Navy needs 4 SSBN for CASD posture
In order to maintain to maintain continuous at-sea deterrence or CASD posture & to have credible & reliable second strike capability, Indian Navy needs minimum 4 SSBN. This will ensure the permanent deployment of SSBN on eastern and western seaboard & uninterrupted deterrence patrol while one or two SSBNs are undergoing maintenance.