Airlines and telecom companies have been at loggerheads over the deployment of 5G mobile services over concerns that the powerful signals could interfere with airplane systems.
Carriers across Asia, the Middle East and Europe canceled flights to the United States or switched planes at the last minute on Tuesday (Jan. 18) and Wednesday (Jan. 19), disrupting travel for thousands of passengers, over safety concerns caused by the 5G deployment.
But Japanese carriers said late on Wednesday they would restore canceled flights and U.S. airlines said thousands of planes were operating normally after two telecom carriers agreed to delay the rollout at key airports.
The decision late on Tuesday by AT&T and Verizon Communications to delay switching on new telecom masts near key airports, just hours ahead of a wider U.S. rollout, came too late to avoid a ripple of cancellations.
The Airport Council International warned the effects could be felt for weeks.
"Passengers and shippers should expect delays and disruptions until these issues are fully resolved," said Vice President for Safety and Regulatory Affairs, Chris Oswald.
Much of the initial disruption hit the Boeing 777, for decades a workhorse of long-distance air travel.
Dubai's Emirates, the world's largest international passenger carrier and the largest 777 operator, hit out at "mixed messages" as it suspended nine U.S. destinations.