India has adopted a turboprop design for its first indigenous regional aircraft and has released preliminary specifications for the planned 70-seater.

National Aerospace Laboratories is looking for foreign partners for the Regional Transport Aircraft RTA-70 and hopes to secure additional government funding later this year.

NAL officials say that they plan to design the RTA-70 with the Indian market in mind, adding that existing turboprops do not meet those requirements. These include improved fuel efficiency, short landing and take-off capability, and the ability to transport cargo.

This will give the aircraft 25% lower acquisition costs, 25% lower operating costs and 50% lower maintenance costs than existing turboprop regional aircraft, says NAL.

 © Siva Govindasamy/Rex Features

"Many towns and cities remain unconnected due to the cost of operations. Short take-off and landing abilities, capability to land on ill-equipped airfields, including all weather operations, can be of very high benefit," NAL says in its RTA-70 brochure.

"Given the high cost of fuel and its implication to operating economics, developing an aircraft that is fuel-efficient compared with present regional aircraft can be very promising. Lower weight, lower drag can mean higher performance and lower emissions. Capability to carry cargo means additional revenue to an operator," NAL says.

"Initial seed funding has enabled preliminary studies preliminary studies to start," it adds. This has been used for work on aerodynamics including computational fluid dynamics and windtunnel studies, it adds, while preliminary studies on sizing, specifications and performance are in progress.

NAL is eyeing a composite airframe. The aircraft will be powered by two "next-generation turboprop engines", it adds. It would have a fly-by-wire control system, open distributed modular avionics, automatic dependence surveillance - broadcast navigation capabilities, and advanced displays.

The aircraft will have better "energy efficiencies" than its current rivals, says NAL. However, it is unable to say when it hopes to move into the detailed design phase and begin the production of the aircraft.

India's state-owned Hindustan Aeronautics will manufacture the aircraft. This agreement will be similar to a deal to produce the Saras utility/transport turboprop, which NAL has developed primarily for the military, and the Tejas light combat aircraft.

NAL is seeking international partners to help it in several areas. Diehl has come on board to help design the cabin and the two teams unveiled a proposed cabin at India Aviation 2010 in Hyderabad.

Source: Flight International