INS ''Arihant'' (SSBN 80) (), is the
lead ship of
India
India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...
's of
nuclear-powered ballistic missile submarines. It is designated S2 Strategic Strike Nuclear Submarine. The 6,000 tonne vessel was built under the
Advanced Technology Vessel (ATV) project at the Ship Building Centre in the port city of
Visakhapatnam
Visakhapatnam (; List of renamed places in India, formerly known as Vizagapatam, and also referred to as Vizag, Visakha, and Waltair) is the largest and most populous metropolitan city in the States and union territories of India, Indian stat ...
.
Arihant was launched on 26 July 2009, the anniversary of ''
Vijay Diwas'' (
Kargil War Victory Day) by
Prime Minister
A prime minister or chief of cabinet is the head of the cabinet and the leader of the ministers in the executive branch of government, often in a parliamentary or semi-presidential system. A prime minister is not the head of state, but r ...
Manmohan Singh
Manmohan Singh (26 September 1932 – 26 December 2024) was an Indian economist, bureaucrat, academician, and statesman, who served as the prime minister of India from 2004 to 2014. He was the fourth longest-serving prime minister after Jaw ...
. After fitting out and extensive sea trials, on 23 February 2016, she was confirmed as ready for operations,
commissioned in August 2016,
and deployed operationally in 2018.
Design
INS ''Arihant'' is the first of the planned five in the class of submarines designed and constructed as a part of the Indian Navy's secretive Advanced Technology Vessel (ATV) project. The ATV project was set up in 1984, under
Vice Admiral
Vice admiral is a senior naval flag officer rank, usually equivalent to lieutenant general and air marshal. A vice admiral is typically senior to a rear admiral and junior to an admiral.
Australia
In the Royal Australian Navy, the rank of Vice ...
Mihir K. Roy as the first Director General. The submarines are reported to be based on the . Their crew were to have the opportunity to train on
INS ''Chakra'', an ''Akula''-class submarine, which the Indian Navy leased from Russia.
''Arihant'' is intended to be more of "a technology demonstrator" than a fully operational SSBN according to
Admiral Nirmal Verma.
The vessel is powered by an 83 MW
pressurised light-water reactor with
enriched uranium fuel.
A land-based prototype of the reactor was first built at
Kalpakkam and made operational in September 2006. Successful operation for three years yielded the data that enabled the production version for ''Arihant''.
It was reported that an 80 MW nuclear reactor was integrated into the hull of the ATV in January 2008.
The hull for the vessel was built by
L&T's Hazira shipbuilding facility.
Tata Power Strategic Engineering Division (SED) built the control systems for the submarine. The systems for the steam turbine integrated with the reactor were supplied by
Walchandnagar Industries.
Consultancy was provided by Russia. Russia was also reported to have provided assistance to
Bhabha Atomic Research Centre (BARC) scientists in miniaturising the reactor to fit into the hull of the nuclear submarine
Armament

''Arihant'' has four vertical launch tubes, which can carry 12 (three per launch tube) smaller
K-15 missiles or four larger
K-4 missiles. The K-4 has a longer range of , and had commenced trials in 2014.
Development phases
A nuclear scientist familiar with the project, on the condition of anonymity, echoed this report in response to media reports that India had successfully launched a completed nuclear submarine.
It was also expected that building the reactor, integration of systems, and sea trials would take three to five years.
Admiral Verma told reporters on 7 August 2012 that sea trials of ''Arihant'' were commencing in coming months, and she was steadily progressing towards operationalisation. On 27 January 2013, Sagarika, the primary armament of ''Arihant'', completed its final developmental test and was later integrated with the submarine.
On 10 August 2013, the nuclear reactor of the submarine went critical
this after several months of system checks using shore-based high-pressure steam.
The reactor's power was raised in increments of 5 to 10% until it reached full power.
Launch
INS ''Arihant'' was introduced to the public on 26 July 2009 at a symbolic launch ceremony by Prime Minister
Manmohan Singh
Manmohan Singh (26 September 1932 – 26 December 2024) was an Indian economist, bureaucrat, academician, and statesman, who served as the prime minister of India from 2004 to 2014. He was the fourth longest-serving prime minister after Jaw ...
's wife
Gursharan Kaur.
The launch coincided with the 10th anniversary of the conclusion of the
Kargil War. The vessel was floated by flooding the dry dock. Gursharan Kaur cracked a
coconut
The coconut tree (''Cocos nucifera'') is a member of the palm tree family (biology), family (Arecaceae) and the only living species of the genus ''Cocos''. The term "coconut" (or the archaic "cocoanut") can refer to the whole coconut palm, ...
on the hull to mark the launch of the submarine, a naval tradition, at the secret naval base in Visakhapatnam.
Photography was prohibited and photos showing the complete vessel were not available. In his address to the crowd, Prime Minister Singh billed the submarine as an outcome of a public-private partnership. He also thanked Russia in his address. The launch of ''Arihant'' strengthened India's endeavour to build a credible
nuclear triad – the capability to fire
nuclear weapons
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either nuclear fission, fission (fission or atomic bomb) or a combination of fission and nuclear fusion, fusion reactions (thermonuclear weap ...
from air, land and sea.
Trials and commissioning

On 13 December 2014, ''Arihant'' sailed north along the Bay of Bengal coast for its extensive sea trials. The sea trials included the firing of the indigenous submarine-launched Sagarika ballistic missile.
On 25 November 2015, an unarmed ''Sagarika'' missile was successfully test-fired from ''Arihant.'' The submarine then underwent further extensive sea trials, which were completed by early February 2016. Though it had initially been expected ''Arihant'' would be commissioned in time to participate in the
International Fleet Review 2016, her participation was subsequently ruled out due to security concerns. On 23 February, ''Arihant'' was officially confirmed as ready for operations.
According to ''
The Economic Times'', several weapons trials of INS ''Arihant'' were undertaken secretly.
In August 2016, Prime Minister Narendra Modi commissioned INS ''Arihant'' into the Indian Navy.
Commissioning and arming ''Arihant'' completed India's
nuclear triad.
Operational history
2017 accident
In January 2018 it was alleged that an aft hatch on the submarine was left open by mistake while the ''Arihant'' was docked in 2017, leading to saltwater flooding the propulsion compartment, rendering the submarine inoperative for ten months while corroding pipes were replaced.
These allegations were dismissed by some sources due to the submarine being based on a
Double hull design as well as claims that it does not have a hatch to the propulsion compartment. Although the Indian Ministry for Defence refused to deny the allegations, claiming it would be a breach of national security to speak on the matter.
First deterrence patrol
It was announced on 5 November 2018 that INS ''Arihant'' had completed its first 20-day long deterrent patrol the previous day.
PM Narendra Modi
Narendra Damodardas Modi (born 17 September 1950) is an Indian politician who has served as the Prime Minister of India, prime minister of India since 2014. Modi was the chief minister of Gujarat from 2001 to 2014 and is the Member of Par ...
congratulated the crew of ''Arihant'' after the patrol.
User training launch
To prove crew competency and validate the SSBN programme, INS ''Arihant'' on 14 October 2022 successfully launched an SLBM with a predetermined range and hit the target area in the Bay of Bengal with high accuracy. As per a defence source quoted by
The Hindu
''The Hindu'' is an Indian English-language daily newspaper owned by The Hindu Group, headquartered in Chennai, Tamil Nadu. It was founded as a weekly publication in 1878 by the Triplicane Six, becoming a daily in 1889. It is one of the India ...
, the missile launched was not the K-4 SLBM but the older K-15 SLBM. At present INS ''Arihant'' is armed with K-15
Sagarika SLBM, which possess a range of 750 km.
See also
* , second submarine in Arihant class
*
List of active Indian Navy ships
* , home-port of the ''Arihant'' class.
*
Submarines of the Indian Navy
This is a list of known submarines of the Indian Navy, grouped by class, and pennant numbers within the class.
In service
Under construction Planned
Decommissioned
See also
; Indian navy related lists
* Aircraft of the Indian ...
References
External links
{{DEFAULTSORT:Arihant
Arihant-class submarines
Ballistic missile submarines
Nuclear-powered submarines
Ships built in India
Submarines of India
2009 ships
India–Russia relations
Submarine classes
fr:Classe Arihant