Trouble beneath the waves: India’s submarine fleet is ageing and replacements are years away

The Navy’s conventional submarine fleet is ageing at a time when the need for new undersea vessels is growing. Yet plans to replace and expand this critical arm of the Navy remain years away from delivery, raising concerns about a widening gap in underwater combat capabilities.The Navy currently operates 16 conventional diesel-electric submarines across three classes (Kalvari, Sindhughosh and Shishumar) alongside three strategic submarines.Its plan to induct 24 conventional submarines by 2030 has fallen behind schedule. Four Sindhughosh-class boats have been retired, including INS Sindhughosh, the lead vessel of the class, while only six Kalvari-class Scorpene submarines have been inducted. The Shishumar-class boats have undergone mid-life upgrades, but average around 35 years in age, and capability gaps remain.