Airline passengers have been warned of potential travel disruption after Airbus identified a "significant number" of A320 planes impacted by a software issue.
Airlines are racing to implement the required software update in order to return aircraft back into service and minimise disruption.
In a statement, the plane maker said: "Analysis of a recent event involving an A320 Family aircraft has revealed that intense solar radiation may corrupt data critical to the functioning of flight controls.
"Airbus has consequently identified a significant number of A320 Family aircraft currently in-service which may be impacted."
It is understood the incident that triggered today's software warning involved a JetBlue flight from Cancun, Mexico, to Newark on 30 October.
That flight was diverted to Florida's Tampa International Airport at around 2pm local time after it suffered a flight control issue and experienced a sharp loss of altitude which injured several passengers.
An Airbus spokesperson told Sky News the necessary software change would affect up to 6,000 planes.
The fix involves A320 aircraft reverting to an earlier software update, with planes unable to fly passengers until this has been completed, according to a bulletin to airlines.
Airbus stressed that for most of the affected aircraft, the required software update would only take 2-3 hours. However, some aircraft would need new hardware to be able to adopt the required software and those aircraft would be affected for longer.
Travel expert Simon Calder said the situation was "very concerning" but that he had full faith in the safety procedures of Airbus and airlines. He went on to say that "aviation remains extraordinarily safe".
However, he warned that customers may not be entitled to cash compensation if affected by delays, as the issue would be considered out of the control of airlines.
EasyJet, British Airways, Aer Lingus, Lufthansa, American Airlines, Delta, Air New Zealand, Flynas and Wizz Air are all affected by the issue.
Gatwick Airport has said the software directive "may result in some disruption" and urged passengers to contact their airlines for more information.
Airbus told Sky News that it had proactively asked the European Union Aviation Safety Agency (EASA) to issue an air worthiness directive for the affected aircraft.
The issue is affecting A319, A320 and the A321 models. Both older and newer neo models are affected.
The company said the issue is only affecting A320s that are in service, not aircraft that are due to be delivered.
The UK Civil Aviation Authority said it is likely to mean some disruption and cancellation to flights.
Some airlines will be more affected than others, Colombian airline Avianca has announced that it will close ticket sales for 10 days due to the issue.
Transport Secretary Heidi Alexander thanked aviation workers and said: "The good news is it seems the impact on UK airlines seems limited, with a smaller number of aircraft requiring more complex software and hardware changes."
She added that it is "heartening this issue has been identified and will be addressed so swiftly", saying that this demonstrated "the high aviation safety standards globally".
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In a statement, easyJet said: "As we are expecting this to result in some disruption, we will inform customers directly about any changes to our flying programme tomorrow and will do all possible to minimise the impact.
We have commenced and already completed the software update on many aircraft which require them and continue to work closely with the safety authorities."
American Airlines said the Airbus software issue would impact 340 aircraft and it expects some operational delays due to a major software change requirement.
The airline added that it expects the vast majority of the updates to be completed by "today or tomorrow", and that they are "intently focused" on limiting cancellations.
Delta, another US airline, also expects the issue to affect a small portion of its fleet - specifically, less that 50 A321neo aircraft.
Wizz Air said some of its flights over the weekend may be affected, while Air India said the issue could lead to delays.
Indigo, an Indian airline which operates over 150 A320s, said it was proactively completing mandated updates on the affected aircraft.
British Airways told Sky News that only three of its aircraft were affected and that the required fixes will be carried out overnight and are not expected to disrupt its operations.
Aer Lingus is in a similar position, with a limited number of aircraft impacted. The airline doesn't expect there to be significant operational disruption, but is taking "immediate steps to complete the required software installations".
Turkish Airlines is already returning eight A320 aircraft to service after completing the required actions.
Heathrow Airport is not currently expecting any disruption to its services.
In October, the Airbus A320 family broke a major milestone when it overtook Boeing's 737 to become the most-delivered jetliner in history.
(c) Sky News 2025: Software issue hits thousands of Airbus planes - UK passengers warned of potential disruptio

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