DRDO facility develops underwater signalling flares for Kalvari-class submarines of Indian Navy

The Signal Star Naval Flare is a specially designed underwater signaling device, tailored to the demanding operational needs of submarines. It is ejected from the submarine’s signal ejector, travels through the water column, and activates upon surfacing. Once at the surface, the flare ignites a high-intensity pyrotechnic charge, producing a bright, star-like light visible at long ranges — even at night or in adverse weather.

The flare is housed in a pressure-resistant casing, ensuring reliable operation even under high underwater pressures. On reaching the surface, hydrostatic mechanisms initiate the flare’s functioning. A specially formulated pyrotechnic composition produces bright red or green star signals, depending on the tactical requirement. These colors are standardized for naval communication.

Red signal flare indicates distress, emergency, or an urgent tactical message while the green signal flare is used for identification, recognition, or as a safe-operational signal during fleet maneuvers. Each flare burns with high luminosity and a sustained duration, ensuring visibility to surface vessels and aircraft, said DRDO officials.

The Signal Star Naval Flares form a critical part of submarine signaling and safety equipment. The red and green star signals provide a universally recognized visual code for submarines to communicate with friendly ships or aircraft without breaking stealth. The red star flares can act as an emergency locator, aiding rescue and recovery operations. These flares are used in naval drills and simulations to coordinate fleet actions and practice tactical signaling. They also provide an option for submarines to mark positions or send coded messages during underwater warfare operations, officials added.

“The successful indigenization of the Signal Star Naval Flare eliminates dependence on foreign suppliers for a critical submarine pyrotechnic. It demonstrates India’s growing mastery in formulating advanced pyrotechnic compositions for high-brightness red and green signals, designing robust housings, and ensuring long shelf-life reliability in harsh marine environments.

This development strengthens India’s underwater warfare capabilities, enhances operational readiness of the Indian Navy, and underscores the country’s progress towards self-reliance in strategic defence technologies,” said the press statement from the MoD.