(Yicai) Dec. 1 -- European aircraft giant Airbus said that about 6,000 A320-family aircraft worldwide must urgently replace a flight-control software program after investigators found it could be corrupted by solar radiation following an incident involving a JetBlue Airways jet in late October.

The finding is significant because it affects more than half of all in-service A320-family aircraft globally, with Chinese carriers alone operating up to 2,015 affected jets. According to Yicai’s understanding, about 11,300 Airbus A320-family aircraft are currently in service worldwide, and the requirement for an urgent software replacement on 6,000 of them means that more than half of the global fleet is affected.

The JetBlue incident occurred on October 30, when an A320 operating from Cancun, Mexico, to Newark, New Jersey, diverted to Tampa, Florida, for an emergency landing after a flight-control malfunction triggered an abrupt, uncommanded drop in altitude that left several passengers hospitalized.

The problem stems from a version of the software that is vulnerable to “particle upset,” a phenomenon in which solar particles cause bit flips in digital chips and disrupt critical data. According to Airbus, intense solar radiation may damage data required for flight control, prompting the instruction to revert to an earlier software version.

An industry insider told Yicai that reverting the software generally takes one to two hours, while only a small number of older aircraft may need hardware changes that could temporarily reduce available capacity.

Some Chinese airlines carried out emergency inspections over the weekend to identify aircraft running the affected software version, leading to delays and cancellations on certain flights. As of the end of November, Chinese carriers had 2,015 A320-family jets in service, accounting for nearly half of the country’s commercial fleet and spread across 24 airlines, according to data from Flight Manager DAST.

Editor: Emmi Laine