The Defence Research and Development Organisation on Tuesday successfully carried out the demonstration of Solid Fuel Ducted Ramjet technology, a critical propulsion system used in long-range missiles, placing India among a small group of countries with this advanced capability. The SFDR system is a missile propulsion technology required for the development of long-range air-to-air missiles being developed by DRDO. Experts said the technology can also be adapted for use in surface-to-air missile