Airbus has grounded around 6,000 A320 family planes after finding that intense solar radiation can interfere with their flight control computers. This issue was found after an October incident where a JetBlue flight between the US and Mexico suddenly lost altitude and made an emergency landing, injuring 15 people. Most affected planes, about 5,100, will undergo a software update that takes roughly three hours, allowing them to fly again. However, 900 older planes need their onboard computers replaced physically before carrying passengers again. The repair time depends on the availability of replacement parts. The UK's aviation regulator warned of "some disruption and cancellations to flights," but airport impact in the UK remains limited. London's Gatwick reported minor disruption, Heathrow saw no cancellations, and Manchester expected no major issues. Airlines are affected differently. British Airways faces little impact, while Wizz Air, Air India, and EasyJet are updating their fleets quickly. Air France faced the most cancellations, scrapping 50 flights at its Paris hub. In the US, American Airlines said 340 planes need updates, expecting some delays, while Delta expects limited impact. Jetstar in Australia canceled 90 flights as a third of its fleet is affected, with disruption continuing through the weekend despite many planes updated. The UK Civil Aviation Authority called this grounding a "very rare event" and reassured people that aviation remains very safe. Transport Secretary Heidi Alexander said the UK impact is limited and commended the swift action to fix the problem. The root cause is a software flaw in the altitude calculation program affected by solar radiation at high altitude. The European Union Aviation Safety Agency has ordered updates before planes return to passenger service, allowing only passenger-free "ferry flights" to maintenance hubs. The A320 family uses "fly by wire" technology, where computer systems control the plane based on pilot inputs with no direct mechanical link, making computer integrity crucial. Airbus apologized for the inconvenience caused by this precautionary grounding.