WASHINGTON: The chief executives of major US passenger and cargo carriers on Monday warned of an impending “catastrophic” aviation crisis in less than 36 hours, when AT&T and Verizon are set to deploy new 5G service.

The airlines warned the new C-Band 5G service set to begin on Wednesday could render a significant number of widebody aircraft unusable, “could potentially strand tens of thousands of Americans overseas” and cause “chaos” for US flights.

“Unless our major hubs are cleared to fly, the vast majority of the traveling and shipping public will essentially be grounded,” wrote the chief executives of American Airlines , Delta Air Lines, United Airlines, Southwest Airlines and others in a letter.

The Federal Aviation Administration (FAA) has warned that potential interference could affect sensitive airplane instruments such as altimeters and significantly hamper low-visibility operations.

“This means that on a day like yesterday, more than 1,100 flights and 100,000 passengers would be subjected to cancellations, diversions or delays,” the letter cautioned.

Airlines late on Monday were considering whether to begin canceling some international flights that are scheduled to arrive in the United States on Wednesday.

“With the proposed restrictions at selected airports, the transportation industry is preparing for some service disruption. We are optimistic that we can work across industries and with government to finalise solutions that safely mitigate as many schedule impacts as possible,” plane maker Boeing said on Monday.

Action is urgent, the airlines added in the letter also signed by UPS Airlines, Alaska Air, Atlas Air , JetBlue Airways and FedEx Express. “To be blunt, the nations commerce will grind to a halt.” The letter went to White House National Economic Council director Brian Deese, Transportation Secretary Pete Buttigieg, FAA Administrator Steve Dickson and Federal Communications Commission (FCC) Chairwoman Jessica Rosenworcel.

Airlines for America, the group that organised the letter, declined to comment. The FAA said it “will continue to ensure that the traveling public is safe as wireless companies deploy 5G. The FAA continues to work with the aviation industry and wireless companies to try to limit 5G-related flight delays and cancellations.” The other government agencies did not comment.

AT&T and Verizon, which won nearly all of the C-Band spectrum in an $80 billion auction last year, on Jan. 3 agreed to buffer zones around 50 airports to reduce interference risks and take other steps to cut potential interference for six months. They also agreed to delay deployment for two weeks until Wednesday, temporarily averting an aviation safety standoff, after previously delaying service by 30 days.

Verizon and AT&T declined comment on Monday. They argue C-Band 5G has been successfully deployed in about 40 other countries without aviation interference issues.

The CEOs of major airlines and Boeing Chief Executive Dave Calhoun held a lengthy call with Buttigieg and Dickson on Sunday to warn of the looming crisis, officials told Reuters.

United Airlines separately warned the issue could affect more than 15,000 of its flights, 1.25 million passengers and snarl tons of cargo annually.

Published in Dawn, January 19th, 2022