By Staff Correspondent
The Combat Vehicles Research and Development Establishment (CVRDE), Chennai of Defence Research and Development Organisation (DRDO) achieved a significant technological milestone on 14 March 2023, with the successful maiden flight test of their indigenously designed and developed Power Takeoff (PTO) Shaft on the Light Combat Aircraft (LCA Tejas) Limited Series Production (LSP) – 3 aircraft in Bengaluru.
The PTO shaft is a critical component in fighter aircraft and their variants, and this successful test was meant to ensure that future fighter aircraft’s requirements will be met with competitive cost and reduced availability time. It may be pertinent to note that the DRDO has achieved this technological feat with the realisation of complex high-speed rotor technology that has only been accomplished by a few countries.
According to those in the know, the PTO shaft was designed using a unique and innovative patented ‘Frequency Spanning Technique’, enabling it to negotiate different operating engine speeds. The light-weight, high-speed and lubrication-free PTO shaft transmits higher power between the aircraft engine gearbox and the Aircraft Mounted Accessory Gear Box while accommodating misalignments that may arise in the drive line.

This development was made possible through the collaboration of various stakeholders ranging from the Aeronautical Development Agency (ADA), Centre for Military Airworthiness and Certification (CEMILAC), Directorate General of Aeronautical Quality Assurance (DGQA), and Hindustan Aeronautics Limited (HAL), who teamed up with CVRDE to achieve this feat. It is worth noting that the PTO shaft technology has already been transferred to Godrej and Boyce, Mumbai and Lakshmi Technology and Engineering, Coimbatore.
The successful realisation of the PTO shaft has been described as a significant milestone towards ‘Aatmanirbhar Bharat’ and was commended by Defence Minister Rajnath Singh, who praised the DRDO, Public Sector Undertakings (PSUs), and the industry. Dr Samir V Kamat, Secretary of the Department of Defence R&D and Chairman of DRDO, emphasised that the success of the PTO shaft showcases the country’s research capabilities and will actively support the test aircraft programmes.
“Overall, the successful maiden flight test of the PTO shaft on the LCA Tejas Limited Series Production – 3 aircraft in Bengaluru is an impressive technological feat and a significant accomplishment for the CVRDE, DRDO, and their collaborators,” said a source when asked about the significance of the development.