INTERNATIONAL: A warning of an impending "catastrophic" aviation crisis in less than 36 hours, when AT&T and Verizon are set to deploy new 5G service has been issued by the chief executives of major U.S. passengers and cargo carriers on Monday, 17 January.

The airlines have warned the new C-Band 5G service set to begin on Wednesday , 19 January could render a significant number of widebody aircraft unusable, "could potentially strand tens of thousands of Americans overseas" and cause "chaos" for U.S. 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.

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

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

Action is urgent, the airlines have added in the letter also signed by UPS Airlines, Alaska Air, Atlas Air, JetBlue Airways and FedEx Express. "To be blunt, the nation's 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 organized 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 January 3 has 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 has declined comment on Monday. They argue C-Band 5G has been successfully deployed in about 40 other countries without aviation interference issues.

The FAA has said on Sunday it had cleared an estimated 45 percent of the U.S. commercial airplane fleet to perform low-visibility landings at many airports where 5G C-band will be deployed and they expect to issue more approvals before Wednesday. The airlines noted on Monday that the list did not include many large airports.

^{PHOTO: UNITED AIRLINES, AMERICAN AIRLINES AND DELTA PLANES TAKING OFF, TAXIING AND STATIONARY ON TARMAC / AMERICAN AND DELTA TERMINALS / INSTALLATION OF VERIZON 5G NETWORK / STILL IMAGES OF U.S. TRANSPORT SECRETARY PETE BUTTIGIEG AND FEDERAL AVIATION ADMINISTRATION HEAD STEVE DICKSON / STILL IMAGES OF PLANES FLYING OVER WIRES}