The Indian Ministry of Defence (MoD) announced in a statement:
“The missile was tested to a predetermined range and impacted the target area in the Bay of Bengal with very high accuracy. All operational and technological parameters of the weapon system have been validated”.
The Indian MoD added that the successful user training launch of the SLBM by INS Arihant is significant to prove crew competency and validate the SSBN program, a key element of India’s nuclear deterrence capability. A robust, survivable and assured retaliatory capability is in keeping with India’s policy to have ‘Credible Minimum Deterrence‘ that underpins its ‘No First Use’ commitment.
The exact type of SLBM used in the test was not disclosed. These could be K-15 ‘Sagarika’ or K-4 missiles. K-15 can deliver a 1,000 kg warhead about 400 nautical miles. Twelve of them can be deployed by Arihant. However this missile is seen as an interim solution.  The newer K-4 is a full-size SLBM (Submarine Launched Ballistic Missile). This is expected to have a range of around 1,900 nautical miles, almost 4 times that of the K-15.
But based on the large area covered by the NOTAM, the missile tested today was likely the K-15:
About INS Arihant
Few submarines are less photographed than India’s two Arihant-class ballistic missile submarines (SSBNs). The lead boat, INS Arihant (S2), was commissioned in 2016 and a second boat, INS Arighat (S3) is expected to join her in service this year.
The Arihant is a unique design which can be characterized as a ‘pocket boomer’. It is much smaller than other ballistic missile submarines (North Koreas’ conventionally powered boats excepted). Its hull is shorter and thinner than its contemporaries and it only carries four missile silos.
To learn more about the Arihant-class, check out this story by H I Sutton:
