FAA Issues SAIB on Risk of Potential Adverse Effects on Radio Altimeters


In an ongoing effort to address the overlap between modern 5G rollout and established aviation frequency use and technology, the Federal Aviation Administration has issued the following Special Airworthiness Information Bulletin to equipment and aircraft manufacturers, operators and pilots.

In part, the SAIB states: "This Special Airworthiness Information Bulletin informs aircraft manufacturers, radio altimeter manufacturers, operators, and pilots of the planned deployment of wireless broadband networks in the 3700-3980 MHz bands, which is scheduled to begin on Dec. 5, 2021, in the 3700-3800 MHz bands. This SAIB recommends that radio altimeter manufacturers, aircraft manufacturers, and operators voluntarily provide to federal authorities specific information related to altimeter design and functionality, specifics on deployment and usage of radio altimeters in aircraft, and that they test and assess their equipment in conjunction with federal authorities. Results from that testing and assessment should be reported to the appropriate civil aviation authorities and spectrum regulators. The FAA is currently collaborating with the Federal Communications Commission and the National Telecommunications and Information Administration to assess the need for mitigation beyond the recommended action in this SAIB."

To read the Special Airworthiness Information Bulletin in its entirety, click here.


The Aircraft Electronics Association encourages member shops to share the SAIB with their customer base. The AEA has been participating in an industry coalition to evaluate the safety concerns and find a reasonable resolution to the concerns.

To read about the latest coalition effort and a request that a group be formed with the involvement of the Commission, the FAA, 5G interests and the aviation industry to address these concerns, click here.

To read the Nov. 5, 2021, industry coalition letter to the National Economic Council calling for a delay to the deployment of 5G technologies to the C-band until the safety and efficiency of the national airspace system is ensured, click here.

To read the Nov. 18, 2021, industry letter to the Federal Communications Commission in reply to CTIA’s comments on 5G, click here.

On Dec. 7, 2021, the FAA issued two airworthiness directives to provide a framework and to gather more information to avoid potential effects on aviation safety equipment. The read the FAA’s statement with links to the ADs, click here.

Contact Ric Peri, AEA vice president of government and industry affairs, by email at ricp@aea.net or by phone at 202-589-1144.