FAA proposes helicopter flight-manual limits in Canadian 5G airspace

The FAA has proposed an airworthiness directive for helicopters with radio altimeters that could be affected by 5G interference in Canadian airspace. Published on Oct. 8, it covers aircraft from 20 named manufacturers, including Airbus, Bell, Leonardo, MD Helicopters, Robinson and Sikorsky.

Wireless broadband signals may cause altimeter readings to behave abnormally without pilots or aircraft systems noticing, the agency said. It described the risk as greatest close to the ground.

Under the proposal, operators of helicopters that have not shown their radio altimeters can tolerate interference would have to update their rotorcraft flight manuals before flying in Canada. Some offshore approaches that depend on radio-altimeter minimums would be barred, along with hover and search-and-rescue autopilot modes that use altimeter data, and departure or arrival phases requiring that data.

The proposal follows a change in Canada's 5G interference protections. Transport Canada told the FAA in March that adjustments taking effect on July 1, 2026, would leave helicopter radio altimeters operating in a harsher interference environment.

Helicopters modified to demonstrate the required tolerance would be exempt from the operating limits. The FAA estimates roughly 5,500 U.S.-registered helicopters carry radio altimeters, and that 1,128 of those could be equipped for the affected operations. Revising a flight manual would cost about $85 per aircraft, it said, and helicopters that do not fly in Canada would face no costs.

Comments are being accepted through Nov. 23, 2026.