The US Federal Aviation Administration FAA issued a warning on Thursday that new 5 G wireless service could still disrupt flights, saying there were big differences between US aviation protections and those in France.
Late Thursday, the FAA launched a dedicated webpage on 5 G and aviation safety raising questions about the potential impact on sensitive airplane electronics like altimeters.
AT&T and Verizon agreed this week to take similar precautions to those in France. The carriers said on Monday they would delay use of C-Band spectrum for wireless service until Jan. 19 - an agreement aimed at heading off an aviation safety crisis and flight disruptions.
President Joe Biden applauded the deal between wireless carriers and US regulators allowing 5 G deployment in two weeks. The FAA said the delay would allow companies more time to prepare and give them more time to evaluate ways to minimize disruptions to altimeters.
The FAA said 5 G airport buffer zones in France cover 96 seconds of flight, while safety precautions around US airports only protect the last 20 seconds of flight. It said that temporary US lower power levels would be 2.5 times higher than France. It noted that France requires antennas to be tilted downward to limit harmful interference, a rule that the United States lacks.
If there is a danger to the flying public, we are obliged to pause the activity until we prove it is safe, according to the FAA website. Radar altimeters must be proven safe in the US 5 G environment to fly into these airports, so we need to take into account the higher signal strength when assessing safety and risk. AT&T and Verizon won nearly all of the C-Band spectrum in an $80 billion auction last year. In early November, the FAA issued a bulletin warning that could be needed to address potential interference from 5 G, which caused carriers to agree to delay deployment for 30 days to Jan. 5.
The deal on Monday assured AT&T and Verizon they will be able to start service this month, and they agreed to temporary buffer zones around 50 airports that the FAA will identify by Friday.
The FAA said 50 airports are covered because wireless companies only agreed to 50 airports. AT&T and Verizon did not immediately make a statement.
After Jan. 19, Biden said that the agreement puts us on track to reduce disruptions to air operations.
The FAA said that 5 G deployment will increase the risk of disruption during low visibility, including flight cancellations, diverted flights, and delays during periods of low visibility, even with the temporary buffer around 50 airports. The FAA said it is working during the two-week delay to complete evaluations of the most popular altimeters, allowing some aircraft to operate in 5 G and minimize disruptions.