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Fears of 5G interference lead to cascade of U.S. flight delays

A photo of a United Airlines Boeing 777 which is apparently most affected by C-Band 5G interference
(Image credit: Wikipedia/Creative Commons)

Several foreign airlines have made the decision to cancel flights to certain U.S. cities over concerns that U.S. cellular carriers AT&T and Verizon’s C-band 5G network rollout today (Jan. 19) might interfere with instruments that many aircraft use to land in bad weather. 

Reuters reported that Emirates, Air India, Japan Airlines, Korean Airlines, China Airlines, Cathay Pacific, All Nippon Airways, British Airways, Lufthansa, Singapore Airlines and ANA were scrambling to rejig their flight schedules. 

The U.S. Federal Aviation Administration (FAA) is concerned that C-band 5G could mess with the radio altimeters that deliver height readings aircraft need when landing in conditions of poor visibility and for helping with automated landings. 

The U.S. Federal Communications Commission (FCC) insists there is no such danger and that C-band 5G has been successfully deployed in other industrialized countries with no effect on aircraft. (Here's an explanation of what's going on with the C-band 5G rollout.)

Despite AT&T and Verizon both saying they would pause their C-band rollouts near major airports, flights to cities such as San Francisco, Seattle, Boston, Miami and more have been suspended by overseas carriers this morning. 

Only certain models of aircraft could be affected

Emirates noted it was suspending Boeing 777 flights to these destinations “until further notice” as that model of jet uses radio altimeters that the FAA fears may be susceptible to C-band 5G interference. 

This has seen the likes of Singapore Airlines, Austrian Airlines and British Airways change from the Boeing 777 to other aircraft for U.S. flights.

Other commercial passenger aircraft, such as the Boeing 747 and Airbus A320, use more modern radio altimeters and have been cleared by the FAA for safe flying near C-band cell towers. But the FAA still advises that “passengers should check with their airlines if weather is forecast at a destination where 5G interference is possible.” 

U.S. airline operators had previously warned that the rollout of this band of 5G, which sits close to the frequencies used by airplane radio altimeters, could cause “catastrophic disruption” to flight schedules. This appears to be at least somewhat true, despite the fact that AT&T and Verizon both agree to temporarily limit C-band 5G deployment near select airports. 

But as it stands, neither telecom provider has reached an agreement with the FAA on the navigation of C-band 5G around airports. This will likely require the FAA to complete its assessment in how C-band 5G could affect altimeter performance before network rollouts continue and flights return to schedule. 

"We recognize the economic importance of expanding 5G, and we appreciate the wireless companies working with us to protect the flying public and the country’s supply chain," said U.S. Transportation Secretary Pete Buttigieg. “The complex U.S. airspace leads the world in safety because of our high standards for aviation, and we will maintain this commitment as wireless companies deploy 5G.” 

No way, FAA!

5G network

(Image credit: FTZtudio/Shutterstock)

However, in a scathing research note from consultancy firm Strand Consult has dubbed the FAA’s concern over 5G as a “charade” claiming there's “no evidence that 5G harms the operation of altimeters.”

“Ostensibly, the FAA is concerned about interference to outdated altimeters on old planes and helicopters but lacking technical or regulatory standards for altimeters, it appears the FAA has only limited idea of where these obsolete altimeters are and how many are there,” the research note detailed. 

“Despite its acknowledged lack of information, the FAA boasts that US airspace is the most complex in the world and its safety; the best. With more than 40 nations having rolled out 5G on some 200 networks without problems to aviation, the situation with the FAA has become a national embarrassment.”

And from there the note gets harsher: “In fact the FAA attests that it has no evidence of actual interference. The truth can be independently verified, but FAA chose not to do this. Instead the FAA has colluded with various aviation trade associations (pilots, airlines, and aircraft) in the hope that they can get the mobile industry to cough up $100 million or so to pay for altimeter upgrades.”

“Additionally 5G offers a potent opportunity for the FAA to distract public attention from airlines’ poor performance and many regulatory shortcomings. And the FAA has no qualms about bogus safety alerts to scare the public if it fulfills its larger goal: to maintain meaning and tribute from the aviation industry.”

Is there really a problem?

Some 40 other nations have rolled out C-band 5G with no known adverse effects. That, plus the fact that there's a 220-MHz buffer zone between the frequencies used by Verizon and AT&T's C-Band 5G and those of radio altimeters, means Strand Consult may have a point.

“The FAA and the aviation industry have known about 5G in the C-band for years but said and did little to nothing to indicate there was a problem. If 5G was a legitimate safety issue, aviation actors would have acted sooner to prevent deployment in the US and around the world,” Strand Consult explained. “Instead, the FAA and the aviation industry sensed an opportunity. By waiting until the last moment, they could exploit the situation to their advantage.”

Avi Greengart, lead analyst with Techsponential, discussed the topic with Tom's Guide and appears to back up Strand Consult's research note: "In the U.S., the 5G we’ve been using has either been used before for prior wireless networks, or it is on really high frequencies with no ability to penetrate a piece of paper, let alone an airplane."

"Barring someone walking in with a barrel of money to placate the airlines, carriers are going to turn on the frequencies with buffer zones around airports, and then we’ll see if the FAA actually mandates anything in terms of flight restrictions."

Nevertheless, as it stands, Strand Consult can make these scathing observations and claims, but until the FAA completes its investigation it seems more time will be needed before flight disruption and schedule changes will be cleared up for flights to certain U.S. airports.

Roland Moore-Colyer a Managing Editor at Tom’s Guide with a focus on news, features and opinion articles. He often writes about gaming, phones, laptops and other bits of hardware; he’s also got an interest in cars. When not at his desk Roland can be found wandering around London, often with a look of curiosity on his face.