The chief executives of major U.S. 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 services.

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 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 in a letter first reported by Reuters.