AT&T and Verizon plan to move forward with new 5G deployments on Wednesday, rejecting a late request by the heads of the DOT and the FAA for an additional delay.
The Biden administration is concerned that the deployments will interfere with aircraft landings and approaches.
In a strongly worded letter Sunday, AT&T CEO John Stankey and Verizon CEO Hans Vestberg noted that they already voluntarily delayed 5G rollout for a month at the behest of the FAA and airlines despite having invested billions of dollars in preparation for the rollout.
The upcoming deployment, they said, is vital to address wireless connectivity 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.
Their letter followed a Dec. 31 request by DOT secretary Pete Buttigieg and FAA administrator Steve Dickson that the companies delay the 5G launch by up two weeks so that the FAA can have more time to identify airports that will be imperiled by interference from nearby C-Band base stations.
The C-Band spectrum encompasses a frequency range that is closer to frequencies used by aircraft than has previously been allowed in the U.S. Airlines and the FAA say that such broadcasts could interfere with aircraft radio altimeters, which are used primarily to measure a plane's distance from the ground when flying at altitudes of approximately 2,500 feet and below.
As a result, the FAA intends to issue a series of notices prohibiting pilots from landing in low-visibility conditions at impacted airports.
The trade group Airlines for America, which on Dec. 30 filed a petition with the Federal Communication Commission for an emergency stay on the initiation of C-Band broadcasts around a long list of U.S. airports, says that without effective mitigations, the 5G deployment could disrupt as many as 345,000 passenger flights each year.
In their letter, Buttigieg and Dickson said that failure to reach a solution by Jan. 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."
They told the AT&T and Verizon CEOs that the FAA would use an additional two-week delay to identify the priority airports and to issue the appropriate flight-approach rules to pilots. They also said the FAA would identify priority airports where a buffer zone would permit flights to continue safely.
"Our goal would then 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."
In rejecting the proposal, Stankey and Vestberg noted that they obtained their broadband licenses via an auction overseen by the FCC.
"Agreeing to your proposal would not only 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 essential to our country's economic vitality, public safety and national interests as the airline industry," the CEOs wrote.
Still, while refusing the DOT and FAA, the executives did lay out their own mitigation plan, They said that through July 5 they will implement C-Band radio exclusion buffers that are similar to those currently being deployed in France.
"That approach -- which is one of the most conservative in the world -- 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."