Verizon and AT&T said on Tuesday that they would delay the expansion of new 5G cellular service near some airports, a pause that President Biden said would avert potentially devastating disruptions that airlines had been warning about for months.
The broader expansion of 5G — which provides much faster access to the internet than current wireless technology — is set for Wednesday after multiple delays.
Aviation regulators and airlines repeatedly raised concerns that the new technology would interfere with safety equipment used to determine a plane’s altitude. The telecommunications industry has countered that regulators and airlines have had years to prepare for 5G.
It was not immediately clear whether the changes that AT&T and Verizon announced were enough to prevent severe flight disruptions on Wednesday. A few foreign carriers canceled flights to the United States, while several major U.S. airlines and an industry trade group said late Tuesday that they were still trying to understand the details of the delay. Wireless companies and Mr. Biden did not say how long the delay would last.
The Federal Aviation Administration, which oversees flight safety, said in early January that it had reached a deal with AT&T and Verizon that included delaying the start of the new 5G service by two weeks and adding safeguards around airports. But that agreement appeared to be insufficient when airline executives sent a letter to the administration on Monday claiming that the start of the service could cause such huge problems that the “nation’s commerce will grind to a halt.” Mr. Biden echoed those warnings.
“This agreement will avoid potentially devastating disruptions to passenger travel, cargo operations and our economic recovery,” Mr. Biden said in a statement on Tuesday commending the delay by the wireless carriers. More than 90 percent of the planned 5G expansion will proceed as scheduled, and federal officials will continue to work with those carriers, airlines and aviation manufacturers to find a “permanent, workable solution,” he added.
AT&T and Verizon said they would not activate the new 5G service within two miles of some runways, in line with a request from airline officials. AT&T said the F.A.A. would choose which specific runways required the measure.
The last-minute change, along with previous 11th-hour agreements, highlights poor planning and lack of coordination among the aviation and telecommunications industries and their regulators, the F.A.A. and the Federal Communications Commission.
“It doesn’t just disrupt air travel. It makes us look ridiculous to the rest of the world,” said Harold Feld, senior vice president at Public Knowledge, a research and advocacy group that has received funding from AT&T and Verizon.
In their letter on Monday to Transportation Secretary Pete Buttigieg, the executives of 10 airlines said they feared chaos because of restrictions put in place by aviation regulators to avoid interference between the new wireless service and plane equipment. The airline group offered a solution in the letter: Allow 5G to be put in place nationwide starting on Wednesday, except for within two miles of affected runways.
On a day like Sunday, the group said, more than 1,100 flights would have been canceled because of the F.A.A. restrictions, affecting about 100,000 passengers.
“We have not yet seen the details of the agreements,” Nicholas E. Calio, the chief executive of Airlines for America, an industry association, said in a statement on Tuesday. “However, this pause provides the opportunity to ensure all stakeholders, consumers and the U.S. economy are served in the long run.”
The new 5G service, which is a big expansion of the limited current use of the technology by U.S. wireless companies, uses so-called C-band frequencies, which are close to the portion of airwaves used by radio altimeters, devices that determine the distance between planes and the ground. That measurement is particularly important to pilots when visibility is limited.
Several international airlines said on Tuesday that they would cancel or suspend flights to the United States on Wednesday because of the start of 5G service. They included Air India, Emirates, Japan Airlines and All Nippon Airways.
In a letter to staff on Tuesday before the delay was announced, American Airlines’ chief operating officer, David Seymour, had warned of “major operational disruptions” caused by the 5G rollout because the potential for interference is not fully understood.
“To be very clear, we’re incredibly disappointed that we are at this point, that the entire U.S. airline industry is facing major disruption as new wireless technology is activated,” he said. “The two should be able to coexist, but that only comes with better understanding of potential impacts.”
The industry and the aviation regulators had raised concerns about 5G interference over the past several years. In November 2020, for example, the International Air Transport Association, a global trade group, warned that such interference could trigger automated systems to intervene in ways that would be dangerous and confusing to pilots. The system might, for example, force planes to pull up to avoid phantom objects, or could prevent planes from warning pilots of real obstacles.
Airlines and the F.A.A. began escalating warnings in recent months, leading Verizon and AT&T to delay their limited 5G rollout from December to early January. At the start of this month, the F.A.A., which is part of Mr. Buttigieg’s department, reached an agreement for the delay to Wednesday, buying more time to prepare safety precautions.
The F.A.A. said at the time that it would no longer ask for further delays after Verizon and AT&T agreed to that postponement, and Airlines for America said it would “continue to work with all stakeholders to help ensure that new 5G service can coexist with aviation safely.”
The telecommunications industry has pushed back against the concerns raised by the airlines and the F.A.A., noting that the start of 5G has been years in the making and that the service has already been introduced in Britain, France and other countries.
“In our opinion, the technical information that is being used to generate concern shows improbable worst-case scenarios,” GSMA, a global wireless industry group, said on Monday. AT&T and Verizon also expressed frustration on Tuesday with the F.A.A.’s handling of the situation.
The F.A.A. has noted, however, that there are technical differences in how 5G is being carried out in other countries. In the United States, planes would have been protected from 5G interference only in the last 20 seconds of flight, compared with 96 seconds in France, for example.
Last week, the F.A.A. started issuing hundreds of notices to airlines with updated guidance on how to land planes equipped with different radio altimeters safely in low-visibility conditions where 5G service is of concern. On Sunday, the agency said it had cleared an estimated 45 percent of the U.S. commercial plane fleet to perform such landings safely, opening up runways at as many as 48 of the 88 airports most directly affected by potential 5G interference. The agency did not identify which airports had yet to be cleared.
The planes approved include some Boeing 737, 747, 757 and 767 models, as well as some Airbus A310, A319, A320, A321, A330 and A350 models, the F.A.A. said.
Lawmakers and safety experts have criticized the aviation agency in recent years for failing to anticipate and prevent the problems that caused two fatal crashes of the Boeing 737 Max plane in Indonesia and Ethiopia, killing 346 people and leading global aviation regulators to ban the plane for nearly two years.
Wireless providers have spent billions of dollars for access to airwaves for their 5G service, reflecting how the next-generation network is central to their business ambitions.
Jessica Rosenworcel, the chairwoman of the F.C.C., which regulates wireless providers and auctioned the airwaves for the new service last year, hailed Tuesday’s agreement in a statement.
She said the F.A.A. could “resolve any remaining concerns” using its process to assess whether cockpit equipment was likely to clash with the 5G service. “It is essential that the FAA now complete this process with both care and speed,” she said.