FILE – A Dreamliner 787-10 arriving from Los Angeles pulls to a gate at Newark Liberty International Airport in Newark, NJ, Monday, Jan. 7, 2019. Federal security officials are ordering operators of certain Boeing planes to adopt extra procedures when landing on wet or snowy runways near impending 5G service because, they say, interference from wireless networks could mean planes need more room to land. The Federal Aviation Administration said Friday, Jan. 14, 2022, that interference could delay the activation of systems like the Boeing 787’s thrust reversers, leaving only the brakes to slow the plane. (AP Photo/Seth Wenig, File)

The airline industry is upping the stakes in a showdown with AT&T and Verizon over plans to launch a new 5G wireless service this week, warning thousands of flights could be grounded or delayed if the rollout takes place close to major airports.

CEOs of the nation’s biggest airlines say wireless service interference on a key instrument on planes is worse than they originally thought.

“To be frank, the nation’s trade is going to stop” unless the service is blocked near major airports, the CEOs said Monday in a letter to federal officials, including Transportation Secretary Pete Buttigieg, who previously sided with the airlines on the matter.

AT&T and Verizon plan to activate their new 5G wireless service on Wednesday after two previous delays to the original plan for an early December rollout.

The new high-speed 5G service uses a segment of the radio spectrum close to that used by altimeters, which are devices that measure the height of aircraft above the ground.

Two weeks ago, the companies reached an agreement with the Federal Aviation Administration to delay service for another two weeks and reduce the power of 5G transmitters near airports. This deadline ends on Wednesday.

AT&T and Verizon say their equipment won’t interfere with aircraft electronics and the technology is used safely in many other countries. Airline industry critics say carriers have had years to upgrade altimeters that may be subject to 5G interference.

The CEOs of 10 passenger and cargo airlines, including American, Delta, United and Southwest, said 5G would be more disruptive than they originally thought, as dozens of major airports that were slated to have Buffer zones to prevent 5G interference with aircraft will still be subject to flight restrictions. announced last week by the FAA, and because these restrictions will not be limited to times when visibility is poor.

“Unless our major hubs are cleared to fly, the vast majority of travelers and shippers will be essentially grounded. This means that on a day like yesterday, over 1,100 flights and 100,000 passengers would be subject to cancellations, diversions or delays,” the CEOs said.