JUSTIN WASTNAGE / LONDON & RADHAKRISHNA RAO / BANGALORE
Thrice-postponed programme set to start again despite weight problems as HAL turns to national laboratory for help
India's Saras multirole utility aircraft is due to resume flight testing in February despite estimates that the maximum take-off weight of the twin-turboprop will be 20%above the 4,500kg (9,900lb) target.
The flight-test programme has been postponed three times since the aircraft's roll-out at last February's Bangalore air show and now Hindustan Aeronautics (HAL) is understood to have been asked by the Indian National Aerospace Laboratory (NAL) design bureau to assist in reducing the excess weight.
HAL designed the wing and the landing gear for the 14-seat commuter and has been told to trim weight by at least 1,000kg. NAL dismisses the weight problems, claiming that all prototypes are overweight at first flight. The programme has suffered several delays since its launch in 1996. Flight tests were originally scheduled to begin in 2000.
Sources in the Council of Scientific and Industrial Research (CSIR), which leads the Saras programme, say the aircraft will be rolled out in the next few weeks from the hangars of Bangalore-based NAL. The pusher-turboprop is designed to provide efficient short-haul air links on feeder routes that are poorly served by mainline air services. CSIR claims the aircraft will operate comfortably from high-altitude airfields on hot days without compromising take-off weight and will use less fuel compared to similarly sized commuters.
HAL will be responsible for producing the Saras, which will have a maximum speed of 340kt (625km/h). Power comes from two Pratt & Whitney Canada PT6A-66 engines driving 2.16m (7ft)-diameter, five-bladed propellers at 2,000rpm in a pusher configuration. The engines are mounted on stub wings on the fuselage rear, resulting in a quieter cabin and undisturbed airflow over the wing.
According to Dr R A Mashelkar, director general of CSIR, the Indian air force "is in the process of ordering six Saras" for use as a multipurpose air transport and surveillance carrier. "We have estimated that India may need some 230-250 such small aircraft for serving on short haul routes."
Source: Flight International