FILE – United Airlines planes are parked at San Francisco International Airport with a maintenance hangar in the background on Wednesday July 14, 2021 in San Francisco. (AP Photo / Eric Risberg, file)

(NEXSTAR) – Federal authorities have identified 50 US airports that will have “buffer zones” when mobile companies activate 5G service in a few weeks. The services will use frequencies in a radio spectrum known as the C-band, which has raised concerns as this could impact flight operations.

Following requests from a large commercial group of airlines – Airlines for America – and Federal Aviation Administration chief Pete Buttigieg and Transportation Secretary Stephen Dickson, AT&T and Verizon recently delay in the deployment of the new 5G service.

Airlines for America has told the Federal Communications Commission that using the 5G C-band near dozens of airports could interfere with devices that measure an aircraft’s height above the ground. Buttigieg and Dickson warned that without delay there would be an “unacceptable disruption” to aviation as flights would be canceled or diverted to other cities to avoid potential aviation safety risks.

The Federal Aviation Administration on Friday released a list of 50 airports nationwide that will have buffer zones when 5G is rolled out by wireless carriers later this month. Buffer zones are intended to reduce the risk that aircraft instruments such as an altimeter, which measures the altitude of the craft, are affected by potential interference.

Altimeters are essential for flights making low visibility landings. According to FAA, planes will need an altimeter “which has been shown to be accurate and reliable in the US 5G C-band environment”.

the listing airports that will have 5G buffer zones include those in New York, Dallas, Chicago, San Francisco, Miami and Las Vegas. Airports were selected based on traffic volume, number of low visibility days and geographic location. These buffers will only protect the last 20 seconds of flight, depending on the FAA.

Many airports are currently not affected by 5G. For airports not on the list, the FAA says that does not “necessarily” mean low visibility flights cannot take place. In some cases, like Denver International Airport, 5G is yet to be deployed. Along with others, the FAA says the 5G towers are far enough apart to create a natural buffer zone.

Mobile carriers are now planning to activate 5G C-band service on January 19.