Airlines around the world canceled and delayed flights heading into the weekend to fix software on a widely used commercial aircraft after an analysis found the computer code may have contributed to a sudden drop in the altitude of a JetBlue plane last month.

Airbus said Friday that an examination of the JetBlue incident revealed that intense solar radiation may corrupt data critical to the functioning of flight controls on the A320 family of aircraft.

The European Union Aviation Safety Agency issued a directive requiring operators of the A320 to address the issue and said it may cause “short-term disruption” to flight schedules. The problem was introduced by a software update to the plane's onboard computers, according to the agency.

In Japan, All Nippon Airways, which operates more than 30 planes, canceled 65 domestic flights for Saturday. Additional cancellations on Sunday were possible, it said.

The software change comes as U.S. passengers were beginning to head home from the Thanksgiving holiday, which is the busiest travel time in the country.

American Airlines has about 480 planes from the A320 family, of which 209 are affected. The fix should take about two hours for many aircraft and updates should be completed for the overwhelming majority on Friday, the airline said. A handful will be finished Saturday.

American expected some delays but it said it was focused on limiting cancellations. It said safety would be its overriding priority.

Delta said it expected the issue to affect less than 50 of its A321neo aircraft. United said six planes in its fleet are affected and it expects minor disruptions to a few flights. Hawaiian Airlines said it was unaffected.

Mike Stengel, a partner with the aerospace industry management consulting firm AeroDynamic Advisory, said the fix could be addressed between flights or on overnight plane checks.

“Definitely not ideal for this to be happening on a very ubiquitous aircraft on a busy holiday weekend,” Stengel said from Ann Arbor, Michigan. “Although again the silver lining being that it only should take a few hours to update the software.”

At least 15 JetBlue passengers were injured and taken to the hospital after the Oct. 30 incident on board the flight from Cancun, Mexico, to Newark, New Jersey. The plane was diverted to Tampa, Florida.

Airbus, which is registered in the Netherlands but has its main headquarters in France, is one of the world's biggest airplane manufacturers, alongside Boeing.

The A320 is the primary competitor to Boeing's 737, Stengel said. Airbus updated its engine in the mid-2010s, and planes in this category are called A320neo, he said.

The A320 is the world’s bestselling single-aisle aircraft family, according to Airbus' website.

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Associated Press writers Mari Yamaguchi in Tokyo and Jennifer Kelleher in Honolulu contributed.