Regulatory Alert: FAA Approves Some Aircraft for Low-Visibility Operations in 5G C-Band Environment; Releases Guidance for Airports on Managing Disruptions
January 16, 2022
The Federal Aviation Administration (FAA) announced that the agency has approved approximately 45 percent of the U.S. commercial fleet to conduct low-visibility operations at many airports located in the 5G C-Band network, which is scheduled to be deployed on January 19. FAA indicated that two radio altimeters have demonstrated that they are not susceptible to 5G interference, allowing a wide variety of Boeing and Airbus airplanes to be approved for these operations. The models approved include some Boeing 737, 747, 757, 767, MD-10/-11, and Airbus A310, A319, A320, A321, A330 and A350 airplanes. The approvals will allow low-visibility operations to occur at 48 of the 88 airports that have been most directly affected by 5G C-Band interference, according to FAA. 
Aircraft operators and aircraft and altimeter manufacturers are continuing to work closely with FAA and the telecoms to obtain additional FAA approvals to conduct low-visibility operations at airports with instrument approach procedures (IAPs) that have been identified by NOTAMs. The agency indicated this evening that they are expecting to issue approvals for additional aircraft in the “coming days.“
In an email to Part 139 airports this evening, FAA released a planning document that provides details on how Part 139 airports can participate in real-time webinars with the FAA Air Traffic Organization (ATO) Command Center to reduce the severity, scope, and duration of any disruptions that may result from the 5G C-Band deployment. The guidance also outlines steps that airports can take in advance of the January 19 rollout. In the email, FAA encouraged airports to revisit their Irregular Operations (IROPS) Contingency Plans to ensure they are prepared for these types of impacts and/or diversion events. Additional information is provided below in our updated Airport FAQs on 5G Impacts. 
AAAE remains in constant communication with senior leadership from FAA, lawmakers, and our airline partners, expressing our concerns over potential operational impacts and working to minimize those impacts to the greatest extent possible.
UPDATED AIRPORT FAQs ON 5G IMPACTS 
AAAE has received many questions regarding the status of potential 5G C-Band operational impacts and has been working with FAA and our industry partners to address your questions. Based on FAA publications and our discussions with the agency, we have developed, and continue to update, the following FAQs to help you navigate the complexities of this 5G issue.
When will the 5G C-Band network be deployed? The 5G C-Band network will be deployed on January 19, 2022. Verizon and AT&T were originally expected to deploy their new C-Band network on December 5, 2021, but it was delayed until January 5 after concerns were raised about potential impacts of 5G signals on aircraft operations. On January 4, the U.S. Department of Transportation (DOT) and FAA reached an agreement with Verizon and AT&T whereby the telecoms agreed to delay the rollout by two weeks to January 19. 
Does AAAE expect any additional delays with the deployment? No, as part of the January 4 agreement between DOT/FAA and the telecoms, the federal government agreed not to seek any further delays in rolling out the 5G C-Band network. 
Where will the 5G C-Band network be deployed? Verizon and AT&T plan to deploy their new 5G C-Band network in 46 different markets across the country. The cities where deployment will occur on January 19 are known as Partial Economic Areas (PEA) 1-4, 6-10, 12-19, 21-41, and 43-50 from a list that the Federal Communications Commission (FCC) has published here. For any city outside of the PEAs identified, the 5G C-Band will not be rolled out in that city until late 2023. You can view a map of the PEAs here. 
What airports will be impacted by the 5G C-Band deployment in the 46 markets? On January 13, FAA released a series of NOTAMs identifying the limitations that have been placed on low-visibility operations when a radio altimeter is required and where the 5G C-Band is deployed. These NOTAMs, which go into effect on January 19, provide additional information regarding each airport that has been affected. You can view and search these NOTAMs on the agency's NOTAM Search website. 
What happens if my airport is located within the 46 markets where the 5G C-Band will be deployed? FAA has issued an aerodrome NOTAM for any airport that could be impacted by the 5G C-Band network that will be deployed in the 46 markets, or PEAs. In addition, the agency has issued a series of IAP NOTAMs that will restrict the IAPs that may be used by operators at specific airports. 
What happens if FAA issued an aerodrome NOTAM for my airport? The operator is prohibited from using autoland, heads-up display (HUD) to touch down, or enhanced flight vision systems (EFVS) to touchdown. These systems can be used if the operator obtains an alternative method of compliance (AMOC) approval from FAA, which is further discussed below. The NOTAM does not mean that the operator is prohibited from landing at the airport. For additional details on aerodrome NOTAMs, see FAA's NOTAM and AMOC Guide that they published in relation to the 5G issue. 
What happens if FAA issued an IAP NOTAM in relation to my airport? The operator can fly a visual or any IAP at your airport that does not have a NOTAM. The IAP NOTAM restricts procedures that require radio altimeters and have visibility requirements less than a half mile. There is an exception: As further discussed below, if the operator has obtained an AMOC approval from FAA, the operator may be able to use IAPs restricted by the IAP NOTAM. For additional details on IAP NOTAMs, see FAA's NOTAM and AMOC Guide that they published in relation to the 5G issue. 
What is an FAA AMOC approval, especially in the context of this 5G issue? On December 9, FAA issued a determination that radio altimeters “cannot be relied upon to perform their intended function“ if they experience 5G interference. This led the agency to issue two airworthiness directives (2021-23-12 and 2021-23-13) for all transport and commuter category airplanes and helicopters equipped with radio altimeters, prohibiting these aircraft from conducting operations identified by NOTAMs (e.g., low-visibility operations when a radio altimeter is required). 
An AMOC approval from FAA is specific to an aircraft and means that an operator has demonstrated to the agency that their aircraft or altimeter models are not susceptible to 5G interference. If an AMOC approval has been secured, the operator will no longer be restricted by the airworthiness directives or any applicable NOTAMs, although the operator will be subject to any terms or conditions identified in the AMOC approval.
What is the likelihood of FAA issuing AMOC approvals in the context of this 5G issue? Has FAA issued AMOC approvals for any aircraft or altimeters to operate in the 5G C-Band environment? As part of the January 4 agreement between DOT/FAA and Verizon and AT&T, the telecoms are sharing 5G data with the federal government. FAA is working closely with aircraft and altimeter manufacturers to review the data, along with altimeter test results, to determine which aircraft can be granted AMOC approvals. 
On January 16, the agency issued AMOC approvals for a series of Boeing and Airbus models, including some Boeing 737, 747, 757, 767, MD-10/-11, and Airbus A310, A319, A320, A321, A330 and A350 models. Additional approvals are expected be issued in the days and weeks ahead.
How many aircraft are expected to receive AMOC approvals to operate in the 5G C-Band environment? To date, FAA has issued AMOC approvals for approximately 45 percent of the U.S. commercial fleet, which will enable these aircraft to perform low-visibility landings at many airports located in the 5G C-Band network after its deployment. This percentage is expected to increase in the days and weeks ahead. 
On January 7, FAA published a list of 50 airports where Verizon and AT&T will create “buffer zones.“ What is a “buffer zone“ and will they be permanent? As part of the January 4 agreement, Verizon and AT&T agreed to implement mitigation measures, called “buffer zones“ or “exclusion zones,“ at 50 airports for a period of six months, or through July 5, 2022. Prior to the agreement, the telecoms were planning to activate 5G antennae that were located within very close proximity to some airports within the 46 markets, or PEAs. Under the deal with DOT/FAA, the telecoms agreed to not activate these antennae around 50 airports, creating “buffer zones“ around the runways. These measures, which are similar to what has been adopted in France, are expected to reduce C-Band signal levels by at least 10 times on the runway or during the last mile of final approach and the first mile after takeoff. You can read additional details about these buffer zones in the telecoms' January 2 letter to DOT and FAA. 
What benefits do the telecoms' “buffer zones“ provide to the 50 airports that were included on the list? According to discussions with FAA, 5G C-Band interference depends on the distance between the aircraft and its altimeter and the 5G antenna and its power level. By reducing the strength of the 5G signals near runways at these airports, FAA can issue additional AMOC approvals for aircraft to operate at these airports, thereby further mitigating the operational impacts of 5G interference. 
How did FAA develop the list of 50 airports where the “buffer zones“ will be implemented by Verizon and AT&T? Why were some airports excluded? The January 4 agreement between FAA/DOT and the telecoms limited the mitigation measures to only 50 airports. In discussions with FAA, the agency has emphasized that not every airport has a 5G antenna in close proximity to its runways. As a result, in developing its list of 50 airports, FAA primarily focused on airports where a 5G antenna was scheduled to be activated near a runway for that airport. FAA believes this is where the telecoms' mitigation measures would be most effective. In addition, FAA considered traffic volume, the number of low-visibility days, and geographic location when selecting the 50 airports. 
What can airports do to manage and/or prepare for potential disruptions and diversion events caused by the deployment of the 5G C-Band network? FAA released guidance for Part 139 airports, which can be viewed here, on how to prepare for and manage potential disruptions and diversion events caused by the deployment of the 5G C-Band network. Airports, especially those that may be impacted by the rollout, have been invited by FAA to participate in real-time webinars with the ATO Command Center to help reduce the scope of 5G operational impacts. These airports have also been encouraged by FAA to review their Irregular Operations (IROPS) Contingency Plans to ensure they are prepared for these types of impacts and/or diversion events. 
On January 16, FAA's Office of Airport Safety and Standards sent the following email, including the planning guidance and additional context, to Part 139 airports:
Dear Colleagues,
The FAA continues to work with the aviation community and wireless companies to reduce the risk of delays and cancellations that would occur after the Jan. 19 5G C-band deployment. The attached document provides critical information about how large, medium, and small hub airports, as well as Part 139 airports that commonly receive diversions, can participate with the Air Traffic Organization Command Center in real time to reduce the severity, scope and duration of these disruptions. We request that you pay special attention to highlighted passages in the Diversion Plan, which indicate actions you or your staff can take before January 19 to be ready.
While any airport can participate, the focus in the near term is for airports with 5G NOTAM'd approaches and those likely to support diversions when low-visibility weather is forecasted. The goal is to facilitate timely communication from airports on operational issues or limitations that could constrain the ability to accept diversions (i.e. Gate, ramp and remote parking availability, airport staffing constraints such as unavailability of ARFF, Customs, TSA, and any other information deemed operationally critical).
Finally, we encourage airports to revisit Irregular Operations (IROPS) Contingency Plans to best manage irregular operations. Since many larger hub airports have systems to assist in this communication and collaboration effort, we ask that those hub airports and diversion airports continue to leverage available tools and information sharing in ongoing IROPS planning efforts.
Why are these restrictions necessary when the 5G C-Band network has been successfully deployed in other countries? FAA published a statement on why 5G C-deployment in the United States is different than in other countries: 
The U.S. airspace is the most complex in the world, and the FAA holds ourselves and our aviation sector to the highest safety standards. Deployments of 5G technology in other countries often involve different conditions than those proposed for the U.S., including: 
• Lower power levels
• Antennas tilted downward to reduce potential interference to flights 
• Different placement of antennas relative to airfields 
• Frequencies with a different proximity to frequencies used by aviation equipment 
• The early stages of the 5G deployment in the U.S. will include mitigations that are partly similar to those used to help protect air travel in France. However, even these proposals have some significant differences.
• Planned buffer zones for U.S. airports only protect the last 20 seconds of flight, compared to a greater range in the French environment.
• 5G power levels are lower in France. In the U.S., even the planned temporary nationwide lower power levels will be 2.5x higher than in France.
• In France, the government required that antenna must be tilted downward to limit harmful interference. Similar restrictions do not apply to the U.S. deployment.
Has FAA published any resources on the 5G C-Band issue? Yes, FAA has a dedicated webpage to the 5G issue that you can find here. AAAE also recommends reviewing the following resources: 
• FAA Safety Alert for Operators (SAFO) 21007, “Risk of Potential Adverse Effects on Radio Altimeters when Operating in the Presence of 5G C-Band Interference“ (Dec. 23, 2021) 
• FAA's List of 50 Airports with Buffer Zones 
• FAA's NOTAM and AMOC Guide on 5G 
• FAA's Planning Guide for 5G and Other Diversion Events (Jan. 15, 2022) 
• FCC PEA Nos. 1-4, 6-10, 12-19, 21-41, and 43-50 (List and Map) 
• Verizon and AT&T's January 2 Letter to DOT/FAA 
• AAAE's December 30 Regulatory Alert on FAA's 5G Impacts Update 
• AAAE's January 4 Regulatory Alert on DOT/FAA Agreement with the Telecoms 
• AAAE's January 8 Regulatory Alert on List of 50 Airports 
• AAAE's January 12 Regulatory Alert on Release of NOTAMs   
The Federal Aviation Administration (FAA) announced that the agency has approved approximately 45 percent of the U.S. commercial fleet to conduct low-visibility operations at many airports located in the 5G C-Band network, which is scheduled to be deployed on January 19. FAA indicated that two radio altimeters have demonstrated that they are not susceptible to 5G interference, allowing a wide variety of Boeing and Airbus airplanes to be approved for these operations. The models approved include some Boeing 737, 747, 757, 767, MD-10/-11, and Airbus A310, A319, A320, A321, A330 and A350 airplanes. The approvals will allow low-visibility operations to occur at 48 of the 88 airports that have been most directly affected by 5G C-Band interference, according to FAA. 
Aircraft operators and aircraft and altimeter manufacturers are continuing to work closely with FAA and the telecoms to obtain additional FAA approvals to conduct low-visibility operations at airports with instrument approach procedures (IAPs) that have been identified by NOTAMs. The agency indicated this evening that they are expecting to issue approvals for additional aircraft in the “coming days.“
In an email to Part 139 airports this evening, FAA released a planning document that provides details on how Part 139 airports can participate in real-time webinars with the FAA Air Traffic Organization (ATO) Command Center to reduce the severity, scope, and duration of any disruptions that may result from the 5G C-Band deployment. The guidance also outlines steps that airports can take in advance of the January 19 rollout. In the email, FAA encouraged airports to revisit their Irregular Operations (IROPS) Contingency Plans to ensure they are prepared for these types of impacts and/or diversion events. Additional information is provided below in our updated Airport FAQs on 5G Impacts. 
AAAE remains in constant communication with senior leadership from FAA, lawmakers, and our airline partners, expressing our concerns over potential operational impacts and working to minimize those impacts to the greatest extent possible.
UPDATED AIRPORT FAQs ON 5G IMPACTS 
AAAE has received many questions regarding the status of potential 5G C-Band operational impacts and has been working with FAA and our industry partners to address your questions. Based on FAA publications and our discussions with the agency, we have developed, and continue to update, the following FAQs to help you navigate the complexities of this 5G issue.
When will the 5G C-Band network be deployed? The 5G C-Band network will be deployed on January 19, 2022. Verizon and AT&T were originally expected to deploy their new C-Band network on December 5, 2021, but it was delayed until January 5 after concerns were raised about potential impacts of 5G signals on aircraft operations. On January 4, the U.S. Department of Transportation (DOT) and FAA reached an agreement with Verizon and AT&T whereby the telecoms agreed to delay the rollout by two weeks to January 19. 
Does AAAE expect any additional delays with the deployment? No, as part of the January 4 agreement between DOT/FAA and the telecoms, the federal government agreed not to seek any further delays in rolling out the 5G C-Band network. 
Where will the 5G C-Band network be deployed? Verizon and AT&T plan to deploy their new 5G C-Band network in 46 different markets across the country. The cities where deployment will occur on January 19 are known as Partial Economic Areas (PEA) 1-4, 6-10, 12-19, 21-41, and 43-50 from a list that the Federal Communications Commission (FCC) has published here. For any city outside of the PEAs identified, the 5G C-Band will not be rolled out in that city until late 2023. You can view a map of the PEAs here. 
What airports will be impacted by the 5G C-Band deployment in the 46 markets? On January 13, FAA released a series of NOTAMs identifying the limitations that have been placed on low-visibility operations when a radio altimeter is required and where the 5G C-Band is deployed. These NOTAMs, which go into effect on January 19, provide additional information regarding each airport that has been affected. You can view and search these NOTAMs on the agency's NOTAM Search website. 
What happens if my airport is located within the 46 markets where the 5G C-Band will be deployed? FAA has issued an aerodrome NOTAM for any airport that could be impacted by the 5G C-Band network that will be deployed in the 46 markets, or PEAs. In addition, the agency has issued a series of IAP NOTAMs that will restrict the IAPs that may be used by operators at specific airports. 
What happens if FAA issued an aerodrome NOTAM for my airport? The operator is prohibited from using autoland, heads-up display (HUD) to touch down, or enhanced flight vision systems (EFVS) to touchdown. These systems can be used if the operator obtains an alternative method of compliance (AMOC) approval from FAA, which is further discussed below. The NOTAM does not mean that the operator is prohibited from landing at the airport. For additional details on aerodrome NOTAMs, see FAA's NOTAM and AMOC Guide that they published in relation to the 5G issue. 
What happens if FAA issued an IAP NOTAM in relation to my airport? The operator can fly a visual or any IAP at your airport that does not have a NOTAM. The IAP NOTAM restricts procedures that require radio altimeters and have visibility requirements less than a half mile. There is an exception: As further discussed below, if the operator has obtained an AMOC approval from FAA, the operator may be able to use IAPs restricted by the IAP NOTAM. For additional details on IAP NOTAMs, see FAA's NOTAM and AMOC Guide that they published in relation to the 5G issue. 
What is an FAA AMOC approval, especially in the context of this 5G issue? On December 9, FAA issued a determination that radio altimeters “cannot be relied upon to perform their intended function“ if they experience 5G interference. This led the agency to issue two airworthiness directives (2021-23-12 and 2021-23-13) for all transport and commuter category airplanes and helicopters equipped with radio altimeters, prohibiting these aircraft from conducting operations identified by NOTAMs (e.g., low-visibility operations when a radio altimeter is required). 
An AMOC approval from FAA is specific to an aircraft and means that an operator has demonstrated to the agency that their aircraft or altimeter models are not susceptible to 5G interference. If an AMOC approval has been secured, the operator will no longer be restricted by the airworthiness directives or any applicable NOTAMs, although the operator will be subject to any terms or conditions identified in the AMOC approval.
What is the likelihood of FAA issuing AMOC approvals in the context of this 5G issue? Has FAA issued AMOC approvals for any aircraft or altimeters to operate in the 5G C-Band environment? As part of the January 4 agreement between DOT/FAA and Verizon and AT&T, the telecoms are sharing 5G data with the federal government. FAA is working closely with aircraft and altimeter manufacturers to review the data, along with altimeter test results, to determine which aircraft can be granted AMOC approvals. 
On January 16, the agency issued AMOC approvals for a series of Boeing and Airbus models, including some Boeing 737, 747, 757, 767, MD-10/-11, and Airbus A310, A319, A320, A321, A330 and A350 models. Additional approvals are expected be issued in the days and weeks ahead.
How many aircraft are expected to receive AMOC approvals to operate in the 5G C-Band environment? To date, FAA has issued AMOC approvals for approximately 45 percent of the U.S. commercial fleet, which will enable these aircraft to perform low-visibility landings at many airports located in the 5G C-Band network after its deployment. This percentage is expected to increase in the days and weeks ahead. 
On January 7, FAA published a list of 50 airports where Verizon and AT&T will create “buffer zones.“ What is a “buffer zone“ and will they be permanent? As part of the January 4 agreement, Verizon and AT&T agreed to implement mitigation measures, called “buffer zones“ or “exclusion zones,“ at 50 airports for a period of six months, or through July 5, 2022. Prior to the agreement, the telecoms were planning to activate 5G antennae that were located within very close proximity to some airports within the 46 markets, or PEAs. Under the deal with DOT/FAA, the telecoms agreed to not activate these antennae around 50 airports, creating “buffer zones“ around the runways. These measures, which are similar to what has been adopted in France, are expected to reduce C-Band signal levels by at least 10 times on the runway or during the last mile of final approach and the first mile after takeoff. You can read additional details about these buffer zones in the telecoms' January 2 letter to DOT and FAA. 
What benefits do the telecoms' “buffer zones“ provide to the 50 airports that were included on the list? According to discussions with FAA, 5G C-Band interference depends on the distance between the aircraft and its altimeter and the 5G antenna and its power level. By reducing the strength of the 5G signals near runways at these airports, FAA can issue additional AMOC approvals for aircraft to operate at these airports, thereby further mitigating the operational impacts of 5G interference. 
How did FAA develop the list of 50 airports where the “buffer zones“ will be implemented by Verizon and AT&T? Why were some airports excluded? The January 4 agreement between FAA/DOT and the telecoms limited the mitigation measures to only 50 airports. In discussions with FAA, the agency has emphasized that not every airport has a 5G antenna in close proximity to its runways. As a result, in developing its list of 50 airports, FAA primarily focused on airports where a 5G antenna was scheduled to be activated near a runway for that airport. FAA believes this is where the telecoms' mitigation measures would be most effective. In addition, FAA considered traffic volume, the number of low-visibility days, and geographic location when selecting the 50 airports. 
What can airports do to manage and/or prepare for potential disruptions and diversion events caused by the deployment of the 5G C-Band network? FAA released guidance for Part 139 airports, which can be viewed here, on how to prepare for and manage potential disruptions and diversion events caused by the deployment of the 5G C-Band network. Airports, especially those that may be impacted by the rollout, have been invited by FAA to participate in real-time webinars with the ATO Command Center to help reduce the scope of 5G operational impacts. These airports have also been encouraged by FAA to review their Irregular Operations (IROPS) Contingency Plans to ensure they are prepared for these types of impacts and/or diversion events. 
On January 16, FAA's Office of Airport Safety and Standards sent the following email, including the planning guidance and additional context, to Part 139 airports:
Dear Colleagues,
The FAA continues to work with the aviation community and wireless companies to reduce the risk of delays and cancellations that would occur after the Jan. 19 5G C-band deployment. The attached document provides critical information about how large, medium, and small hub airports, as well as Part 139 airports that commonly receive diversions, can participate with the Air Traffic Organization Command Center in real time to reduce the severity, scope and duration of these disruptions. We request that you pay special attention to highlighted passages in the Diversion Plan, which indicate actions you or your staff can take before January 19 to be ready.
While any airport can participate, the focus in the near term is for airports with 5G NOTAM'd approaches and those likely to support diversions when low-visibility weather is forecasted. The goal is to facilitate timely communication from airports on operational issues or limitations that could constrain the ability to accept diversions (i.e. Gate, ramp and remote parking availability, airport staffing constraints such as unavailability of ARFF, Customs, TSA, and any other information deemed operationally critical).
Finally, we encourage airports to revisit Irregular Operations (IROPS) Contingency Plans to best manage irregular operations. Since many larger hub airports have systems to assist in this communication and collaboration effort, we ask that those hub airports and diversion airports continue to leverage available tools and information sharing in ongoing IROPS planning efforts.
Why are these restrictions necessary when the 5G C-Band network has been successfully deployed in other countries? FAA published a statement on why 5G C-deployment in the United States is different than in other countries: 
The U.S. airspace is the most complex in the world, and the FAA holds ourselves and our aviation sector to the highest safety standards. Deployments of 5G technology in other countries often involve different conditions than those proposed for the U.S., including: 
• Lower power levels
• Antennas tilted downward to reduce potential interference to flights 
• Different placement of antennas relative to airfields 
• Frequencies with a different proximity to frequencies used by aviation equipment 
• The early stages of the 5G deployment in the U.S. will include mitigations that are partly similar to those used to help protect air travel in France. However, even these proposals have some significant differences.
• Planned buffer zones for U.S. airports only protect the last 20 seconds of flight, compared to a greater range in the French environment.
• 5G power levels are lower in France. In the U.S., even the planned temporary nationwide lower power levels will be 2.5x higher than in France.
• In France, the government required that antenna must be tilted downward to limit harmful interference. Similar restrictions do not apply to the U.S. deployment.
Has FAA published any resources on the 5G C-Band issue? Yes, FAA has a dedicated webpage to the 5G issue that you can find here. AAAE also recommends reviewing the following resources: 
• FAA Safety Alert for Operators (SAFO) 21007, “Risk of Potential Adverse Effects on Radio Altimeters when Operating in the Presence of 5G C-Band Interference“ (Dec. 23, 2021) 
• FAA's List of 50 Airports with Buffer Zones 
• FAA's NOTAM and AMOC Guide on 5G 
• FAA's Planning Guide for 5G and Other Diversion Events (Jan. 15, 2022) 
• FCC PEA Nos. 1-4, 6-10, 12-19, 21-41, and 43-50 (List and Map) 
• Verizon and AT&T's January 2 Letter to DOT/FAA 
• AAAE's December 30 Regulatory Alert on FAA's 5G Impacts Update 
• AAAE's January 4 Regulatory Alert on DOT/FAA Agreement with the Telecoms 
• AAAE's January 8 Regulatory Alert on List of 50 Airports 
• AAAE's January 12 Regulatory Alert on Release of NOTAMs   
