K-4 Missile

The underwater launched ballistic missile is about 12 meters long with a diameter of 1.3 meters. It weighs around 17 tonnes and is capable of delivering two tonne warhead up to a distance of over 3,500 km. The missile is powered by solid rocket propellant.

DRDO in January 2010 was reported to have successfully tested a 3500 km SLBM (sea launched Ballistic Missile). A new missile named K-4 seems to be a different project all together and is not based on Agni-3 which was supposed to be Agni-3 SL (Sub Launched) which was secretly under development. K which has been kept in honor of Dr. Kalam, Father of Indian Missiles in DRDO.

India Today senior editor Sandeep Unnithan, said: "There is a myth created by missile experts on internet forums about SLBM variants of the Agni III and V. They have gone ahead and created several impressions of what it will look like complete with MIRVs etc. The truth is that the K series, and NOT Agni, is the basis for the future SLBM development. This is not contested by the DRDO either. Difficulties with compacting the Agni to fit the 10 metre diameter ATV hull have led to solutions like the K-4.”

The first test of the missile was also conducted secretly on 24 March 2014 and the DRDO admitted it officially only in January 2015 last year in the Aero-India show.

India has reportedly conducted a test of its home grown intermediate range Submarine Launched Ballistic Missile (SLBM) K-4 secretly from an undersea platform in the Bay of Bengal in a bid to boost its deterrence capability by strengthening the second strike fire power. Even as the authorities of Defence Research and Development Organisation (DRDO) are tightlipped about the secret test, a reliable defence source on 09 March 2016 confirmed ‘The Express’ that this nuclear capable missile was fired from a submerged pontoon positioned nearly 30 feet deep sea offshore Vizag coast on Monday. Launched underwater, the missile developed indigenously by the DRDO, surged to the surface leaving behind a ribbon of thick smokes. Although the result of the test was not known, the source claimed it’s take off was smooth as a powerful gas generator successfully ejected it from the pontoon.

By January 2017 India was preparing to test its most ambitious weapon - the K-4 submarine-launched long range ballistic missile (SLBM). The DRDO claims a range of 3,500 km, less than half of China’s JL 2 SLBM. India's state-owned Defense Research and Development Organization (DRDO) was preparing an undersea platform in the Bay of Bengal for the trial of its long-range ballistic missile. The test, code-named K-4, would be conducted in early 2017 anytime.

The 12-meter solid rocket propellant SLBM can carry a warhead, conventional as well as nuclear, weighing up to 2,000 kg. India had tested K 4 three times earlier of a range up to 3,000 km. Government sources said the range in the fourth test would be higher. It is being widely speculated that the indigenously developed submarine INS Arihant would be used for the test as it is capable of carrying 12 K-5 Sagarika missiles and 4 K-4 SLBMs. K 4 was undergoing technical trials followed by development trials in 2018.

Chinese JL 2 SLBM can hit a target up to a range of 8,000 km while Pakistan claims a tanger of 700 Kms for its SLBM Babur Hatf 7. Apart from China, SLBMs are in the possession of Russia, USA, France, and UK. The scheduled test of K 4 came only a short while after the much-hyped back-to-back tests of Agni IV and V in December 2016. China had criticized the tests for violating UN limits on the development of nuclear weapons and long — range ballistic missile.

However, experts argue that India should enhance the range of K series missile. "The K-4 is undergoing technical trials as of 2016. At its maximum range, it could reach some high-value targets in Pakistan from a standoff distance in the Bay of Bengal. It would, however, still fall short of high-value targets on the Chinese mainland or the SSBNs would have to patrol very close to the coastline. With these targets in mind, India will inevitably have to develop an SLBM with a range of 5,000 km," says Brigadier Gurmeet Kanwal, defense expert at Vivekanand International Foundation.

Brig Kanwal wanted India to close the missile-technology gap with both China and Pakistan as early as possible to enhance the credibility of India’s nuclear deterrence. The Chinese state media Global Times has warned New Delhi that if its long-range missile development continues, Beijing would help Pakistan, an "all-weather friend," acquire similar capabilities. However, India said the tests were not aimed at intimidating particular country.

By early 2018 the long range (3,500 kilometers) K-4 missiles had so far been tested three times successfully from underwater pontoons, but the last test from a pontoon in December 2017 failed as the missile did not activate properly during the test.

India successfully tested the K-4 ballistic missile on 19 January 2020, Indian ANI news agency reported, citing government sources. According to the news outlet, the test-firing of the missile was carried out from an underwater platform off the coast of the southern state of Andhra Pradesh. The missile is being developed by the Indian Defence Research and Development Organization. Its firing range is up to 3,500 kilometers (2,200 miles). ?K-4 is one of the two ballistic missiles designed by India to arm submarines. The other missile, called BO-5, has the firing range of over 700 kilometers.

By 2018 it was reported that India had also started working on the K-5, with a range of 5,000 kilometers, as well as the K-6, with its range of up to 6,000 km, for nuclear-powered submarines.