While much of the media attention on the aviation implications for 5G C-band activation has focused on delayed and canceled airline flights that are virtually certain to result from restricting use of instrument approaches and other procedures that rely on radar altimeters, immediate impacts could extend beyond the 1,305 airport notams issued January 13, along with 50 airspace notams and 123 related to precision instrument approaches that require functioning radio altimeters (also known as radar altimeters).
Even with the proverbial ink still drying on the large batch of 5G C-band-related notams, ongoing conversations and negotiations among aviation stakeholders, and between the FAA and the wireless industry, left many questions hanging about what, exactly, will happen when the new 5G C-band transmitters activate on January 19.
The central issue remains potential interference with radar altimeters, which have for decades operated on frequencies near the C-band and are installed in thousands of aircraft, including commercial airliners, some business jets, and many helicopters.
In that last category, helicopters used for emergency medical transportation and flown under Part 135 have been required to have radar altimeters installed since 2017, pursuant to a final rule published by the FAA in 2014. That rule mandated a package of safety requirements and updates, including increased weather minimums that apply to Part 91 helicopter operations. Developed with industry input, the rule was followed in 2015 by an advisory circular directed at helicopter air ambulance operators, recommending training for helicopter air ambulance pilots on a variety of topics including risk assessment and the use of radar altimeters.
The wireless operators who paid tens of billions of dollars to license the C-band spectrum have long resisted calls from a coalition of aviation advocates formed to promote commonsense solutions that allow 5G service to expand without compromising safety. While aviation advocates and the FAA have been accused by the wireless industry of waiting until the last minute to voice concerns, the issue has been on aviation’s radar since long before the FCC licensed the C-band frequencies in 2020. The coalition, of which AOPA has long been an active member, reiterated those concerns in 2021, highlighting the risks C-band transmissions pose to sensitive devices used on thousands of aircraft.
With the FAA poised to issue notams that could render certain instrument procedures unauthorized, Verizon and AT&T agreed in November to delay activation until early January. Two days before that activation date, under intense pressure, the two companies agreed to push the date to January 19.
The FAA recently published a list of 50 airports where Verizon and AT&T have proposed operating nearby C-band transmitters at reduced power for six months, though AOPA has learned that this list might be updated.
For many operators, however, limiting the power of 5G C-band transmission near airports, including over runways and for one mile from the approach and departure ends, is irrelevant. Helicopter Association International, another longtime member of the aviation coalition formed to advocate for a safe approach to 5G implementation, noted January 9 that emergency medical helicopters transport about 1,000 patients daily, more than 300,000 during 2021. About 50,000 of those people were transported from and/or to off-airport locations at night.
“The families of those who die because a helicopter was not able to be dispatched to the scene of an accident because it was too close to a 5G tower will not be consoled by faster internet speeds. The loss of a single life because of misguided 5G-related policies would be reprehensible,” HAI said, noting that the voluntary mitigations (primarily power reduction) proposed by the wireless operators to be applied near up to 50 of the largest airports would have no effect on the safety of off-airport operations. While 55 public-use heliports may enjoy some protection, there are up to 8,533 landing sites established and in use across the country, HAI noted, including more than 4,000 private-use heliports located at hospitals.
“HAI urges policy makers to strongly weigh the irreplaceable benefits to public safety that can only be delivered by helicopters,” HAI wrote. “As regulators spend the next two weeks bridging the gap between the wireless industry’s voluntary measures and what is needed to maintain the safety and usability of the National Airspace System, solutions for helicopter operators must be [prioritized].”
Airline operators and other pilots who rely on radar altimeters for a variety of procedures including precision instrument approaches to major airports in poor weather have warned that flight delays and cancellations are inevitable if C-band transmitters activate without more stringent mitigations in place, though analyzing the effects of the nearly 1,500 notams published January 13 will take time.
AOPA continues to advocate for a commonsense solution that allows 5G C-band service to commence without compromising aviation safety, and commends the FAA for sharing those priorities. The agency created a website to share information and answer common questions about 5G, including an explanation of how mitigations taken in certain foreign countries are significantly different from what AT&T and Verizon have volunteered to adopt in the United States.
“The FAA has done a superlative job handling a tough problem that would have been much easier to tackle had the Federal Communications Commission acted three or more years ago,” said Jim Coon, AOPA senior vice president of government affairs and advocacy. “Protecting the safety of all airspace users is aviation’s most important priority.”