Ruminations: Enhancing Wireless Communications, Impeding Flight Safety

"The United States made all possible spectrum available on a licensed basis to telecom operators."
"Other countries have not done that. That's why it's turning out to be a U.S.-specific issue."
Vivekanand Subbaraman, associate vice president, Ambit Capital, Mumbai

"Unless our major hubs are cleared to fly, the vast majority of the travelling and shipping public will essentially be grounded."
"This means that on a day like yesterday, more than 1,100 flights and 100,000 passengers would be subjected to cancellations, diversions or delays."
CEOs of 10 passenger and cargo airlines including American, Delta, United and Southwest joint statement

"I think the challenge here is that when an airplane is landing in an airport, under instrument conditions, where visibility is very poor, the altimeters give the pilot a sense of how far off the surface he is."
"And so obviously, if this goes wrong, if these signals get corrupted, things can go very, very, very badly."
George Ferguson, senior aerospace and airline analyst, Bloomberg Intelligence

The U.S. aviation regulator, the FAA, came to a last-minute deal to avoid turning dozens of airports into no-fly zones for certain planes, but the bigger issue about whether 5G could interfere with airplanes' ability to land remains unresolved.

Airlines worldwide have been forced to adjust their schedules and aircraft deployment for flights to the United States. Concern has arisen over a 5G rollout by AT&T Inc. and Verizon Communications Inc. located in near proximity to American airports, possibly interfering with vital flight safety systems. In particular flights operated by the 777 and 747-S were specifically affected once Boeing alerted operators of its two largest jetliners they might not safely land at American airports where 5G signals are present.

The issue is related to potential interference with sensitive navigation equipment deployed during landings in poor weather. A trade association which represents major U.S. airlines pointed out that this possible interruption could manifest with "catastrophic disruptions". At issue is the frequencies within the C-band being utilized for the 5G services being close to airwaves used by aircraft radar altimeters tracking altitude and permitting landings in bad weather.

The concern extends to the fact that critical safety systems can also be impeded. Up to 25 flights operated by Boeing 777 jets to the United States were cancelled in one day, according to data from Flightradar24.com. Aircraft owned by Deutsche Lufthansa AG switched to the 747-300 from 747-8 for its Frankfurt-Chicago route.

Dubai's Emirates plans to suspend flights to several American cities including Chicago, Newark and San Francisco. ANA Holdings Inc. and Japan Airlines Co. plan not to fly their 777 jets to and from the U.S. mainland in the wake of an alert from Boeing Co. warning the manner in which the model's altimeter could be affected. A handful of services to the U.S. were cancelled by British Airways which has made some aircraft substitutions.

Korean Air Lines Co. is rearranging its fleet in response to the fact that its 777 and 747-8 aircraft are affected by the 5G service, and Air India Ltd. warned flights to the U.S. are to be curtailed or revised. AT&T and Verizon have agreed after discussions with government officials over safety concerns to delay switching on hundreds of 5G cell towers near American airports.

The companies spent over $80 billion in a government auction for the rights, but provided no details on how long the suspension might last.

After concluding there was no threat to aviation safety, the Federal Communications Commission approved the transfer of the frequencies from other uses to the wireless companies last year. Delta Air Lines Inc. cautioned it was preparing for possible weather-related cancellations should 5G signals cause limited interference with altitude instruments under certain conditions.