CEOs of major US airlines have warned that the deployment of AT&T and Verizon’s new 5G service on Wednesday would cause a “catastrophic” aviation crisis. The new C-Band 5G spectrum is said to affect a significant number of widebody aircrafts, rendering them unusable, which could cause chaos for US airlines and “potentially strand tens of thousands of Americans overseas.”

The chief executives of major airlines including American Airlines, United Airlines, Delta Air Lines, and Southwest Airlines wrote in a joint letter, seen by Reuters, that a significant majority of travelling and shipping public will be grounded unless their major hubs are given the all-clear to fly. The letter was addressed 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.

Impact of C-Band 5G Deployment on Airlines

At the beginning of this month, the FAA issued a warning that C-Band 5G interference could affect sensitive equipments such as altimeters that would impact its functioning in low-visibility areas. It requested AT&T and Verizon to delay their plans for commercial deployment which was initially set for January 5.

Though the carriers initially declined the request, they eventually agreed to hold off on 5G deployment until January 19. They also agreed to work on avoiding potential interference by implementing buffer zones around 50 airports. Verizon and AT&T earlier noted that C-Band 5G has already been successfully rolled out in nearly 40 countries without interference issues. Last year, both carriers won nearly all of the C-Band 5G spectrum in an auction that cost them a whopping $65 billion.

Major US airlines highlighted the urgency of the matter, in the letter which was also signed by shipping companies such as FedEx Express and UPS Airlines, by adding that with the new C-Band 5G service, “the nation’s commerce will grind to a halt.” United Airlines said that it could adversely impact 15,000 flights and 1.25 million passengers annually and urged that the size of the buffer be reduced further.

The FAA said that it has already given the green signal for nearly 45 percent of the U.S. commercial airplane fleet to perform low-visibility landings at airports where the 5G C-Band will be rolled out. It added that the organization will work with the airline industry and wireless companies to limit flight delays and cancellations that could arise from 5G deployment.