Chennai: Researchers at the Indian Institute of Technology Madras (IIT Madras) have achieved a major breakthrough in developing a Vertical Take-off and Landing (VTOL) aircraft and unmanned aerial vehicle (UAV) powered by hybrid rocket thrusters — a move that could significantly advance India's next-generation aerospace technologies.

The team demonstrated a “soft landing” using a real-time hybrid rocket thruster integrated with a virtual simulation through a hardware-in-the-loop simulation (HILS) setup — a cost-effective and flexible testing framework for complex systems. The experiment achieved a touchdown velocity of 0.66 m/s, validating the potential of hybrid rocket propulsion for controlled vertical landings.

The study, led by Prof. P.A. Ramakrishna, Dr. Joel George Manathara, and researcher Anandu Bhadran from the Department of Aerospace Engineering, has been published in the International Journal of Aeronautical and Space Sciences.

Prof. Ramakrishna said VTOL technology can eliminate the need for long runways, enabling aircraft to operate in remote terrains. “Once the VTOL system reaches commercial readiness, it will be a game-changer in both civil and military aviation,” he noted, adding that it could decentralise air transport and enhance strategic flexibility.

Dr. Manathara highlighted the unique use of hybrid rocket thrusters in VTOL applications. “Our system integrates a live-firing hybrid rocket motor within the HILS loop, offering unmatched testing accuracy and safety,” he said. The research also introduced a new hybrid rocket fuel using compressed air as the oxidiser, enhancing integration and safety.

Bhadran said the study proved hybrid rockets can dynamically respond to control inputs for precise thrust modulation, making them viable for VTOL and other precision-controlled aerospace applications.

IIT Madras plans to extend the research toward multi-thruster attitude stabilisation and full-scale prototype testing, marking a step closer to operational VTOL platforms powered by hybrid rocket systems.