The heads of the DOT and the FAA asked for an additional delay in the deployment of new 5G networks, but AT&T and Verizon decided to go ahead with it.
The deployment will interfere with landings and approaches.
The CEOs of AT&T and Verizon wrote a letter on Sunday saying that they had voluntarily delayed the 5G roll out for a month at the request of the FAA and airlines despite having invested billions of dollars in preparation for the roll out.
The upcoming deployment is crucial to address the needs of millions of American families.
"With continued Covid crises, it has never been more important that our country's critical communications infrastructure have the spectrum needed to handle escalating traffic demands from our customers," Stankey and Vestberg wrote.
DOT secretary Pete Buttigieg and FAA administrator Steve Dickson requested that the companies delay the launch of 5G by two weeks so that the FAA can identify airports that will be affected by interference from nearby C-Band base stations.
The FAA and airlines say that broadcasts in the C-Band spectrum could interfere with aircraft radio altimeters, which are used to measure a plane's distance from the ground.
The FAA plans to issue a series of notices prohibiting pilots from landing in low-visibility conditions.
Airlines for America filed a petition with the Federal Communication Commission for an emergency stay on the start of C-Band broadcasts around a long list of U.S. airports.
Failure to reach a solution by January 5 would result in widespread and unacceptable disruption as airplanes divert to other cities or flights are canceled, causing ripple effects throughout the U.S. air transportation system.
The FAA told the AT&T and Verizon CEOs that they would use an additional two weeks to identify the priority airports and issue the appropriate flight-approach rules to pilots. They said the FAA would identify priority airports where flights would be allowed to continue safely.
"Our goal would be to identify mitigations for all priority airports that will enable the majority of large commercial aircraft to operate safely in all conditions," Buttigieg and Dickson wrote. "This will allow for 5G C-band to deploy around these priority airports on a rolling basis, such that C-band planned locations will be activated by the end of March 2022, barring unforeseen technical challenges or new safety concerns."
Stankey and Vestberg obtained their broadband licenses through an FCC auction.
"Agreeing to your proposal would be an unprecedented and unwarranted circumvention of the due process and checks and balances carefully crafted in the structure of our democracy, but an irresponsible abdication of the operating control required to deploy world-class and globally competitive communications networks that are every bit as."
The executives said that they will implement C-Band radio exclusion buffers that are similar to those currently being deployed in France, even though they refused the DOT and FAA.
"That approach is one of the most conservative in the world and would include extensive exclusion zones around the runways at certain airports," Stankey and Vestberg wrote. The effect would be to further reduce C-band signal levels by at least 10 times on the runway or during the last mile of final approach and the first mile after takeoff.
