New Delhi, Nov. 29 -- A sudden software update at 6,000 operational Airbus A320 aircraft has forced airlines worldwide to scramble, with the company alerting operators on Friday of immediate repairs, right in the middle of the year's busiest travel weekend.

This setback, which appears to be one the biggest recalls affecting Airbus in its 55-year history, comes after a software issue caused a sudden drop in altitude of a JetBlue plane last month, the manufacturer and European aviation safety regulators said on Friday.

Airbus said an analysis of the JetBlue incident revealed that intense solar radiation may have corrupted data essential to the aircraft's flight-control systems, leading to the malfunction on the A320, AP reported.

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