The FAA estimates its newly issued airworthiness directives will affect 1,000 US-registered aircraft.
Some US transport aircraft will face operating restrictions in Canada starting on 1 July.
That is according to the US Federal Aviation Administration, which on 30 June published several airworthiness directives (ADs) in response to concern that 5G cellular signals near Canadian airports could interfere with aircraft radio altimeters.
The ADs, which take effect on 1 July, include a blanket directive covering all transport and commuter aircraft, with separate orders specific to Boeing types including 737s, 747s, 757s, 767s, 777s and 787s.
They apply to an estimated 1,000 US-registered transport and commuter aircraft that lack radio altimeters updated to be “tolerant” to 5G interference. The FAA says the rest of the fleet – some 7,000 aircraft – have interference-tolerant altimeters. Airlines updated many altimeters in recent years to address interference with US 5G signals.
The potential operational impact from the FAA’s orders remains unclear. US trade group Airlines for America did not immediately respond to a request for comment, nor did Boeing.
The FAA acted because on 1 July Canada will eliminate protections near airports, which were put in place in 2023 to prevent 5G interference. Those measures, which helped ensure aircraft with older, not-updated altimeters could safely operate, included 5G “exclusions and protection zones” and requirements for 5G signal angles.
Now that Canada is removing those protections, the FAA says 5G signals, which transmit in a range adjacent to altimeters, could cause interference.
“In May 2026, Boeing reported that certain airplane configurations will not demonstrate tolerance to radio altimeter interference in the new 5G environment in Canada,” an FAA AD says.
The directives specify different restrictions for different aircraft types – but again, only for those with non-tolerant altimeters.
For instance, affected 747-8s and 777s will be prohibited from landing in Canadian airspace “in the presence of” Lower C-band interference, while 757 and 767 pilots will need to follow new procedures when landing in Canada.
Non-tolerant 787s and 737 Max will be prohibited from landing in Canada if certain systems – such as anti-skid and braking systems – are among items specified in their minimum equipment lists. And affected 737 Max jets will not be allowed to land on some icy runways.
The FAA’s orders require airlines to update aircraft flight manuals with the restrictions.
The post FAA limits some operations in Canada due to 5G interference risk first appeared on FlightGlobal.