After speaking out against the 5G wireless network rollout, the Federal Aviation Administration (FAA) is now working with aviation and wireless companies to find a solution to allow 5G C-band and aviation to 'safely coexist'.The FAA initially voiced concerns that the 5G wireless networks would interfere with cockpit safety systems that utilize radar altimeters.These cockpit systems help pilots navigate in poor weather and avoid midair collisions. Commercial pilots that are unable to use these features will not be able to fly, leading to flight cancellations and delays in large metropolitan cities like New York City, Los Angeles, Houston where these towers are located.The Federal Communications Commission (FCC), which regulates commercial use of airwaves, countered the FAA's concerns, saying there hasn't been enough evidence to support claims that 5G will interfere with aircraft systems.While the FAA called for a closer look at the safety impacts of 5G technology in November, industry groups like AOPA, EAA and NBAA pushed for a working group to form to examine the issue and spur cooperation between the FCC and FAA.The 5G rollout initially planned for December 5 was pushed until January 5 while ATandamp;T, Verizon, and agency officials assessed the impact on aviation safety.On December 23, the FAA said that Notices to Air Missions (NOTAMs) may be issued to restrict operations in areas where 5G interference is possible.A Safety Alert for Operators (SAFO 21007) was issued the same day, regarding the "risk of potential adverse effects on radio altimeters when operating in the presence of 5G C-band wireless broadband signals."The SAFO went on to say that the deployment of 5G wireless broadband networks in the C-band will be limited to "46 predetermined areas known as Partial Economic Areas (PEAs)." The FAA will issue NOTAMs identifying the areas, airports, and heliports where the radio altimeter is unreliable due to 5G C-band interference.The FAA also issued ADs 2021-23-12 and 2021-23-13 to address operations immediately at risk, such as those requiring a radio altimeter to land in low visibility.To address prohibitions in the two ADs, the FAA will use four types of NOTAMs to identify the areas affected by the 5G interference. The agency expects to issue four types of NOTAMS: Airspace, Aerodrome, Instrument Approach Procedure, and Special IAP.Example Airspace NOTAM:ZHU AIRSPACE RDO ALTIMETER UNREL WI AN AREA DEFINED AS XXXNM RADIUS OF XXXXXXNXXXXXXXW (VOR/DME) SFC-5000FT AGL. HEL OPS REQUIRING RDO ALTIMETER DATA FOR OFFSHORE INSTRUMENT OPS, HOVER AUTOPILOT MODES, SAR AUTOPILOT MODES, AND CAT A/B/PERFORMANCE CLASS TKOF AND LDG NOT AUTHORIZED EXC FOR ACFT USING APPROVED ALTERNATIVE METHODS OF COMPLIANCE DUE TO 5G.Additional examples of the NOTAM types can be found in the safety alert.