The FAA has prepared samples of the NOTAMs it may start issuing starting Jan. 5 when 5G broadband service begins in 46 cities. If the NOTAMs are issued, they would drastically affect operations of airlines, commuter airlines and many charter and business aircraft. In a statement issued Dec. 23, the agency said it will disallow the use of many instrument approaches and any aircraft systems that rely on radar altimeter data including autoland, head-up displays and enhanced vision systems “where 5G interference is possible.”
In the statement, the agency says it’s working with the FCC and telecom operators to allow the systems to safely coexist but until that process is complete it’s ready to start restricting operations if it thinks there’s a chance that radar altimeter can be rendered unreliable by 5G. Below is a sample NOTAM of the type that could be issued covering any or all airports the FAA think might be affected by 5G. Again, it’s not a real NOTAM. It’s just a sample of what could be issued when 5G goes live on Jan. 5.
Example Aerodrome NOTAM for airports:
BDL AD AP RDO ALTIMETER UNREL. AUTOLAND, HUD TO TOUCHDOWN, ENHANCED FLT VISION SYSTEMS TO TOUCHDOWN NOT AUTHORIZED EXC FOR ACFT USING APPROVED ALTERNATIVE METHODS OF COMPLIANCE DUE TO 5G C-BAND INTERFERENCE PLUS SEE AIRWORTHINESS DIRECTIVE 2021-23-12
And below is a sample of a NOTAM covering instrument approaches:
Example IAP NOTAM against impacted approaches (SA CAT I / II, CAT II, III, or RNP AR):BDL IAP BRADLEY INTL, WINDSOR LOCKS, CT. ILS RWY 06 (SA CAT I AND SA CAT II), AMDT 13A… ILS RWY 06 (CAT II AND CAT III), AMDT 38A… RNAV (RNP) Z RWY 06, AMDT 1… RNAV (RNP) Z RWY 24, AMDT 1… PROCEDURE NOT AUTHORIZED EXC FOR ACFT USING APPROVED ALTERNATIVE METHODS OF COMPLIANCE DUE TO 5G C- BAND INTERFERENCE PLUS SEE AIRWORTHINESS DIRECTIVE 2021-23-12
There could also be NOTAMS issued for private airfields with GPS approaches and helicopter operations requiring radar altimeters for hover autopilot modes, search and rescue autopilot modes and heliport instrument approaches. The FAA does say it will allow exemptions for those who have approved alternative methods of compliance but we’re not aware of any exemptions that have been issued. There are concerns that 5G signals, which use 3700-3998 MHz, can overpower radar altimeter signals, which operate in the 4200-4400 MHz band. So far the FCC and the telecoms have maintained that there is no evidence that such interference will occur but the FAA and aviation groups have said there is no proof that it won’t.