Airbus has ordered urgent repairs for about 6,000 A320-family aircraft after discovering that intense solar radiation could corrupt flight-control data.

The recall—one of the largest in Airbus history—was prompted by an October JetBlue flight that abruptly lost altitude, injuring passengers.

Airlines must revert affected jets to an earlier software version before they can fly, with the fix taking about two hours per plane.

Major U.S. carriers including American, Delta, United, and JetBlue are affected, though most expect only minor delays as they complete updates, Fox Business has reported.

International airlines such as Lufthansa, IndiGo, easyJet, and Avianca are also implementing repairs, with Avianca temporarily halting ticket sales due to the scale of impact on its fleet.