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5G Wireless Interference. Update.

February 2022


On Jan 19, 2022, AT&T and Verizon flipped the switch on their 5G networks. These networks operate between 3.7-3.98 gigahertz within the C-Band frequency spectrum. This frequency range is close to the frequencies used by the radar altimeters installed in most commercial and business aircraft. The radar altimeter provides real-time measurements of the aircraft’s altitude over terrain and obstacles. It’s a critical piece of equipment in today’s integrated cockpits.

The FAA, DOT, Lawmakers, and others in the aviation community have expressed concerns about the potential for the 5G network signals interfering with radar altimeters. Both AT&T and Verizon have agreed to temporarily delay putting transmitters near certain airports in response to the concerns from the aviation industry. This delay will give us time to further understand the impact of 5G on aviation safety.

The FAA has released the following:

  • A list of 50 airports in the U.S. with 5G buffer zones. Most of these airports are in bigger cities that mainly serve the airlines.

Buffer airports - https://www.faa.gov/sites/faa.gov/files/2022-01/50%20Airports%20with%205G%20Buffer.pdf

  • A SAFO (Safety Alert for Operators) that provides information and guidance to operators regarding the risk of potential adverse effects on radar altimeters in the presence of 5G broadband signals.

FAA SAFO 21007 Date: 12/23/21 - https://www.faa.gov/other_visit/aviation_industry/airline_operators/airline_safety/safo/all_safos/SAFO21007R1.pdf

  • Two ADs (Airworthiness Directives) applicable to all transport or commercial aircraft and helicopters regarding the adverse effects on radar altimeters from 5G interference. These ADs prohibit certain operations in the presence of 5G C-Band interference or at airports identified by NOTAM (Notices to Airman).

AD 2021-23-12:


AD 2021-23-13: 


To date, the FAA has issued more than 1,300 NOTAMs related to enroute or terminal 5G interference. These NOTAMs restrict operations using Autoland, HUD/enhanced vision systems, and helicopter autopilot hovering unless the operator is using alternate methods of compliance outlined in the FAA’s recently released airworthiness directives on 5G.

The 5G and radar altimeter concerns are not yet fully resolved. We encourage you to stay informed. Here are a few more links to relevant websites.

Industry and FAA updates

  • The FAA has created an online resource at faa.gov/5G.
  • NBAA has created an online resource with the latest news on this subject at nbaa.org/5g.
  • Gogo Business Aviation has issued a white paper, 5G and Spectrum Interference Concerns for Aviation, that directly addresses these concerns, and Gogo 5G