On January 11, 2025, Hindustan Aeronautics Limited (HAL) achieved a significant milestone in its Combat Air Teaming System (CATS) program with the successful completion of the engine ground test for the CATS Warrior unmanned combat aerial vehicle (UCAV).

This development represents a crucial step forward in India's indigenous defence capabilities and sets the stage for future engine co-development partnerships, particularly with Rolls-Royce, which has expressed keen interest in collaborating with HAL on advanced propulsion systems.

The January 11, 2025 Ground Test Achievement

The engine ground test conducted at HAL's Bangalore facility marked a critical milestone in the CATS Warrior program. The test involved a full-scale demonstrator of the loyal wingman drone, which is designed to operate alongside manned fighter aircraft such as the HAL Tejas, Su-30MKI, and Rafale. The successful 15-minute ground run validated the engine's functionality and represented the culmination of extensive research and development efforts by HAL's various centers.

The CATS Warrior demonstrated during this test is powered by two HAL PTAE-W turbojet engines, which are enhanced versions of the earlier PTAE-7 engine developed in the 1980s. Each PTAE-W engine delivers 380 kgf (3.7 kN) of thrust with a specific fuel consumption of 1.15 kg/kgf/hr. The engines measure 1.27 meters in length, have a diameter of 330 mm, and weigh 65 kg each. This dual-engine configuration provides approximately 7 kN of combined thrust, ensuring redundancy and balanced power distribution for the 2,100 kg maximum take-off weight aircraft.

Current Engine Limitations And Future Requirements

While the PTAE-W engines successfully powered the ground test, HAL has acknowledged that these are interim solutions with limited power output. The current engines are based on technology developed for target drones and pilot training aircraft, making them suitable for initial testing but inadequate for the full operational requirements of the CATS Warrior program. Industry sources indicate that the production version of the CATS Warrior will require significantly more powerful engines to meet its operational parameters, including a maximum speed of Mach 0.9, a combat radius of 350 km, and the ability to carry a 650 kg payload.

HAL's long-term engine development strategy includes the indigenous HTFE-25 (Hindustan Turbo Fan Engine), a 25 kN thrust turbofan engine that has been in development since 2013. However, this program has faced significant delays, with production now projected for 2030. The HTFE-25 was originally designed for trainer aircraft, UAVs, and light combat aircraft, making it a potential candidate for powering the CATS Warrior in its final configuration.

Rolls-Royce Partnership Interest And Collaboration Framework

Rolls-Royce has emerged as a key potential partner for HAL's engine co-development initiatives, building on their established relationship spanning over 68 years. The British aerospace giant has expressed significant interest in partnering with HAL for the co-development of engines specifically designed for the CATS Warrior and other Indian UCAV programs. This interest aligns with Rolls-Royce's broader strategy to strengthen its presence in India's defence sector and double its supply chain sourcing from the country by 2030.

The partnership framework being discussed encompasses several key elements. Rolls-Royce has demonstrated its commitment to technology transfer and indigenous capability building through existing collaborations, including the International Aerospace Manufacturing Pvt Ltd (IAMPL) joint venture with HAL, which produces complex aero-engine components for global markets. The company's proposal for UCAV engine development emphasises co-development rather than simple technology transfer, focusing on building end-to-end capabilities that would allow India to own intellectual property rights for advanced combat engine technologies.

Strategic Context And Technological Implications

The CATS Warrior program represents India's entry into the rapidly evolving domain of manned-unmanned teaming (MUM-T) operations, where autonomous drones work alongside human pilots to enhance combat effectiveness while reducing risk to personnel. The successful engine ground test demonstrates HAL's capability to integrate complex propulsion systems with autonomous flight control systems, mission computers developed by the Systems and Laboratory Research and Development Centre (SLRDC), and indigenous avionics packages.

The program's strategic importance extends beyond the immediate tactical advantages of loyal wingman operations. The CATS Warrior is designed to serve multiple roles, including reconnaissance, electronic warfare, precision strikes, and sacrificial missions in heavily contested airspace. Its ability to carry both internal and external weaponry, including Smart Anti-Airfield Weapons (SAAW) and air-to-air missiles, makes it a versatile platform for diverse mission profiles.

Manufacturing And Production Scalability

HAL's approach to CATS Warrior production reflects a modern understanding of defence manufacturing requirements, with plans to involve private sector partners to achieve production targets of nearly 100 units annually.

The company has already demonstrated successful public-private collaboration, with Tata Advanced Systems delivering a CATS Warrior prototype to HAL in February 2025. This collaborative approach is essential for meeting the Indian Air Force's anticipated large orders for loyal wingman systems, which could require 3-4 units per strike package or operational formation.

The cost-effectiveness of the CATS Warrior, estimated at $5-10 million per unit compared to $50-100 million for traditional manned fighters, makes it an attractive option for force multiplication. This economic advantage, combined with the reduced risk to human pilots, supports the case for extensive procurement and deployment across multiple Indian Air Force squadrons.

Future Engine Development Roadmap

The engine development timeline for the CATS Warrior program involves multiple phases and potential pathways. In the immediate term, HAL will continue testing and refining the PTAE-W engines while advancing the HTFE-25 program toward production readiness by 2030. Simultaneously, discussions with Rolls-Royce and other international partners are progressing toward establishing a co-development framework for next-generation engines specifically designed for UCAV applications.

The potential Rolls-Royce partnership could accelerate engine development timelines while ensuring technology transfer and indigenous capability building. This collaboration would leverage Rolls-Royce's expertise in advanced propulsion systems while building on HAL's existing infrastructure and engineering capabilities. The partnership framework under discussion stresses joint development rather than simple procurement, aligning with India's strategic autonomy objectives and the "Make in India" initiative.

Broader Defence Industry Implications

The successful CATS Warrior engine ground test and the emerging partnership with Rolls-Royce represent broader trends in India's defence industry transformation. The program demonstrates the maturation of India's aerospace engineering capabilities, from initial concept development through prototype testing to production planning. The integration of multiple indigenous systems, including mission computers, flight control systems, and communication links, showcases the depth of India's defence technology ecosystem.

The international interest in collaboration, particularly from Rolls-Royce, reflects the growing recognition of India as a significant defence technology partner rather than merely a market for foreign systems. This shift toward collaborative development and co-production aligns with global trends in defence partnerships and India's strategic objectives for defence self-reliance.

The CATS Warrior program's success could serve as a model for future Indian defence projects, demonstrating the effectiveness of public-private partnerships, indigenous technology development, and strategic international collaboration in achieving complex defence capabilities.

As the program progresses toward first flight testing in late 2025 or early 2026, it will provide valuable insights into the operational effectiveness of loyal wingman systems and inform future developments in autonomous combat aviation.

The January 11, 2025 engine ground test thus represents not merely a technical milestone but a strategic inflection point in India's defence modernisation journey, positioning the country at the forefront of next-generation combat aviation technologies while building the industrial capabilities necessary for long-term defence self-reliance.

IND (With Agency Inputs)