AT&T and Verizon are unwilling to further delay 5G deployments on C-band spectrum, as the CEOs of both companies effectively dismissed another last-minute plea from aviation regulators.

Both carriers intend to proceed with mid-band 5G activations on Jan. 5, despite ongoing and seemingly unresolved concerns raised by the Federal Aviation Administration (FAA) and Department of Transportation (DOT) regarding potential spectrum interference with aviation equipment.

The latest plea arrived on New Year’s Eve and was jointly signed by the heads of the FAA and DOT. It asked AT&T and Verizon to delay their commercial use of C-band spectrum by two weeks. 

The carriers in early November 2021 begrudgingly volunteered to delay the use of spectrum they licensed for a combined $68.9 billion until the first week of January 2022, and company executives are in no mood to push the activation of service back any further.

FAA Requests Another Weeks-Long Delay

It’s unclear what the FAA accomplished during the first month-long delay, but it’s now requesting an additional two weeks to identify priority airports that will require buffer zones and to notify pilots of aircraft that might require alternative means of flight safety compliance.

5G radio interference with altimeters, which measure how close an aircraft is to the ground, is the central concern, according to the FAA. The agency now claims, absent further delays, it will be forced to take steps that “will result in widespread and unacceptable disruption as airplanes divert to other cities or flights are canceled,” particularly during periods of low visibility or poor weather conditions.

EJL Wireless Research founder Earl Lum dismissed the FAA’s concerns as posturing during a phone interview prior to this latest request for a delay. “I don’t think there’s any real issue, and if your altimeter is that old you should get a new altimeter,” he said. 

“They did the same thing with Bluetooth way back when … and they had a major problem with WiFi. They have a major problem with everything,” Lum said. 

Verizon, AT&T Reject FAA Oversight

AT&T CEO John Stankey and Verizon CEO Hans Vestberg also reiterated their respective positions in a joint response to the FAA and DOT’s request for an additional delay. “At its core, your proposed framework asks that we agree to transfer oversight of our companies’ multi-billion dollar investment in 50 unnamed metropolitan areas representing the lion’s share of the U.S. population to the FAA for an undetermined number of months or years,” the CEOs wrote in a letter published by The Wall Street Journal.

AT&T and Verizon volunteered to increase the size of exclusion zones around airports and repeated a pledge to not deploy 5G in C-band spectrum near major airports for six months. 

The FAA said it’s reviewing the latest proposal from AT&T and Verizon, but time is running out. Both companies plan to begin deploying 5G on C-band spectrum in the next few days. 

Regulators and wireless operators expressed disappointment about the down-to-the-wire impasse, with parties on both sides claiming they’ve met every responsibility and obligation. However, a general lack of urgency until recently remains a major point of contention. 

AT&T and Verizon contend that the FAA failed to do its due diligence in a timely manner, but the FAA notes it initially raised concerns about potential spectrum interference in 2015. 

The agency also claims it raised concerns again in 2020 and requested a postponement ahead of the C-band auction, but subsequently blames the National Telecommunications and Information Administration for failing to put that formal request into the Federal Communications Commission’s (FCC) docket.

FAA’s Lack of Urgency Blasted

Verizon and AT&T note that C-band spectrum was auctioned following years of study by the FCC, including input from the aviation industry. Moreover, the carriers added, altimeters operate in a frequency band that is separated by at least 400 megahertz from the C-band frequencies. 

“Nonetheless, the FCC encouraged the aviation community to use the nearly two years before C-band deployment to upgrade any altimeters that might not be properly designed to filter out frequencies far removed from the 4.2-4.4 GHz altimeter band,” the carrier CEOs wrote. 

“Inexplicably, the FAA and the aviation industry apparently did nothing following the February 2020 order or even after the C-band auction closed in January 2021. In fact, it was not until November 2, 2021 that the FAA even issued a notice to begin collecting data about altimeters from the aviation industry,” Stankey and Vestberg added.

Verizon previously pledged to cover 100 million people with mid-band 5G in 46 markets by March 2022. AT&T hasn’t made a near-term commitment regarding mid-band coverage, but claims it will reach 200 million people by the end of 2023.