New Delhi, Nov. 29 -- India's aviation regulator on Saturday asked airlines not to fly A320-family aircraft pending mandatory modifications and software fixes, after aeroplane maker Airbus warned that solar radiation could corrupt flight-control data on many in-service jets.

The directive covers 338 jets, 56% (189 aircraft) of which have already received the software upgrade by Saturday afternoon, said the Directorate General of Civil Aviation (DGCA).

InterGlobe Aviation-owned IndiGo, India's largest airline by market share and Airbus' biggest customer in the country, has completed the software upgrade on 160 of its 200 affected jets, according to the DGCA. A total of 363 aeroplanes of IndiGo's 417 aircraft belong to the A320 family.

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