5G NOTAMs Restrict Instrument Flight
The FAA has published 1460 NOTAMs that restrict operations that rely on radio altimeters. The NOTAMs were issued just before the planned rollout of nationwide 5G cellular service by Verizon and AT&T. The companies are using a thin slice of the so-called C-Band of radio spectrum for the service and radio altimeters operate within 200 to 400 MHz of the much more powerful cell signals. Until the impact of the 5G signals on altimeters is known and mitigated, the agency has determined that the use of head-up display (HUD) and enhanced flight vision systems (EFVS) to touchdown, autoland, and helicopter operations requiring radio altimeter data including hover autopilot modes and CAT A/B performance class takeoffs and landings can’t be done where 5G signals are present. The FAA did make an exception for helicopter air ambulance operations but required extra crew training and additional operational requirements especially to conduct night operations.
