India's Tejas light combat aircraft programme has suffered a new setback, with sea-level fight tests using two prototype aircraft having demonstrated lower than expected engine performance during take-off and maximum speed demonstrations.

But in a fresh move intended to steady the troubled programme, New Delhi in mid-August announced a co-operative agreement under which its defence industry will develop the aircraft's multi-mode radar with Israel Aerospace Industries' Elta Systems subsidiary.

Conducted from Arakkonam in India's southern Tamil Nadu state and intended to demonstrate the Aeronautical Development Agency aircraft's performance under dense atmospheric conditions, the recent series of 24 flights revealed that the Tejas was unable to reach its expected maximum speed of Mach 1.05, despite having reached M1.6 at high altitude.

The failure has been attributed to insufficient available thrust from the aircraft's General Electric F404 engine, and underlines India's need to replace the US design with the Kaveri powerplant now under development by its Gas Turbine Research Establishment. In common with the wider Tejas programme, the Kaveri project has been dogged by development delays and cost escalations, which have forced New Delhi to order additional F404s to power its initial production batch of lightweight fighters.

Prototype and demonstrator examples of the Tejas have now flown 725 flights, and the type is due to achieve initial operational capability in late 2010.

Announcing the new radar pact, defence minister A K Antony said India's parliament has approved the co-development agreement with Elta, with Hindustan Aeronautics selected to lead the project. The initiative will replace previous work conducted by the Bangalore-based Electronics and Radar Development Establishment, with technical hitches having prevented a radar design from being integrated with a prototype Tejas.

Antony says the new fire-control radar is needed to support demonstration flights of the fully developed and armed fighter from 2010, and Israeli sources reveal that the sensor will be a further development of Elta's EL/M-2052 active electronically scanned array.

The company is completing development of the design using IAI's Boeing 737 flying testbed, and an undisclosed air force recently placed a $95 million contract to acquire the system. Elta says the AESA design can detect up to 64 targets simultaneously, while it can also provide ground mapping services and be used against maritime threats.




Source: FlightGlobal.com