Iaf Demands Warranty On Hal Aircraft

Concerned with crashes of Hindustan Aeronatutics Ltd (HAL)-manufactured warplanes, the Indian Air Force (IAF) has demanded warranty from the monopoly manufacturer certifying the trouble-free period the aircraft will fly for. According to a Defence ministry technical probe, 82 out of 187 fatal crashes from 1992 - 97 was due to technical defects. 1529 "incidents" or minor problems were traced to technical problems during the same period. These were attributable to manufacturing and overhauling by HAL, which gets all IAF contracts for the purpose.

When this was brought to HAL's notice, the company representatives refused to accept failures as pertaining to their technical personnel, manufacturing techniques or quality assurances. The IAF has suffered a loss of over Rs. 300 crore due to loss of fighter and transport planes. Of the total IAF accidents, 67 per cent was due to technical problems, human error and bird hits were blamed for the rest. The MiG-21 planes , the largest fleet in the IAF and mostly of 1960s and 70s vintage comprised the maximum number of accidents. Interestingly, accidents due to technical defects rose while that due to bird hits and human error showed a progressive decline during 1992-97.

 

Even the Comptroller and Auditor General (CAG) has pointed out that accident rate of IAF fighter planes due to technical defects is a high 79 per cent while that of trainer planes is 23 per cent. In other air forces, this is reverse as most accidents occur due to human error during training. Pointing to a specific case, of a Mig-21 crash in July 1996, the IAF probe said it was traced to a malfuction of a jet nozzle involving damage to a gear pinion manufactured by HAL.. However, HAL did not agree to it. The court of inquiry emphasised the need to check all gears of the same lot to establish if there had been any deviation from laid down technology during manufacture of these gears.

A sugsequent inquiry by the National Aerospace Laboratory (NAL) found serious lapses in the laid down technology parameters. Another accident in October 1996 was traced to a similar failure. Following the incident, the Air headquarters decided to ground all MiG-21 varients fitted with R-11 engines (those fitted with the HAL gears) . Similarly, an Avro aircraft crash in December 1996 was traced to a jet pipe swing link of the engine during servicing. Random checks revealed similar defects in 90 per cent fleet which should have been detected at HAL during overhaul. The IAF has reduced its accident rate in 1998 with some four crashes till date.

IAF chief S K Sareen has attributed this to better management of its training schedules and introducing new methods of depot-level maintenance.

For new aircraft like the MiG-29 and the recently acquired Sukhois, the IAF follows the procedure laid down by the manufacturers since technology has not been transferred in their case.