Airportman.id – The Federal Aviation Administration (FAA) has released a list of airports in the United States that will be surrounded by a buffer zone that will not receive C-Band 5G service.

This buffer zone is designed to separate wireless and aircraft signals following reports that the 3.6 GHz band used by the C-Band 5G network interfered with civilian aircraft radar altimeters.

The FAA's selection of the 50 airports was based on the amount of traffic, the number of days of low visibility, and geographic location. Some of the major airports in the United States that are included in the list include John F. Kennedy International Airport (JFK), Los Angeles International Airport (LAX), and San Francisco International Airport (SFO).

The two C-Band 5G service providers that won nearly all C-Band spectrum supply contracts, AT&T and Verizon, agreed to turn off transmitters at some 50 airports for six months. The deactivation is intended to minimize the 5G network potential for interference with sensitive aircraft instruments used in low-visibility landings.

Quoted from Aviation Today, an AT&T spokesperson stated, "At Secretary Buttigieg's request, we have voluntarily agreed to one additional two-week delay of our deployment of C-Band 5G services. We also remain committed to the six-month protection zone mitigations we outlined in our letter. We know aviation safety and 5G can co-exist and we are confident further collaboration and technical assessment will allay any issues."

The aircraft's radar altimeter operates in the 4.2–4.4 GHz range, the lower part of which falls within to the C-Band frequency range of 3.7–4.2 GHz, where the combination of signal transmission range and capacity is optimal. This month, the 5G wireless networks that AT&T and Verizon are scheduled to enable will occur in the 3.7–3.98 GHz frequency range, close to the altimeter, which has aviation industry experts worried about signal interference issues.

C-Band's 5G technology was initially slated to be activated on December 5. However, this date was pushed back twice due to security concerns, with service carriers continuing to negotiate with the FAA for the next launch date.