More 5G-related cancellations as Paine Field fog persists

EVERETT — With fog still blanketing the Everett area, Alaska Airlines was forced to cancel six flights from Paine Field on Tuesday morning over concern that 5G cellular phone service might conflict with aircraft navigation.

It was the second day the Seattle-based carrier canceled a significant number of commercial passenger flights at the Snohomish County-owned airport.

On Monday, Alaska canceled 23 flights arriving and departing Paine Field — its entire schedule — due to the rollout of 5G cellular technology near the airport.

Alaska currently operates a dozen daily round trips from Paine Field. It is the only airline that serves the two-gate passenger terminal.

The cancellations are the combined result of last week’s 5G activation, poor weather conditions and the type of aircraft that Alaska employs at the Snohomish County-owned airport.

Embraer 175 jets, which Alaska Air Group subsidiary Horizon Air operates at Paine Field, have not been cleared by the Federal Aviation Administration to land in low visibility conditions near 5G towers.

The 5G network could interfere with the plane’s radio altimeter and other crucial onboard systems, officials say.

Radio altimeters provide highly accurate information about an aircraft’s height above the ground. The data informs other safety equipment on the plane, including navigation instruments and collision-avoidance systems, according to the Federal Aviation Administration.

As a safety measure, FAA is prohibiting the operation of certain airplane models until their altimeters have been approved for operation in a 5G environment when poor weather prevails.

“Aircraft with those altimeters will be prohibited from performing low-visibility landings where 5G is deployed because the altimeter could provide inaccurate information,” the FAA said in a statement.

Paine Field was one of 50 airports listed by federal regulators that would be impacted by the 5G rollout that began last week across markets in the United States.

The Boeing Company’s test schedule at Paine Field has not been affected, a Boeing spokesman said on Tuesday.

Fog is expected to persist through Thursday, although it could dissipate in the afternoons, according to the National Weather Service.

Federal regulators continue to evaluate which radio altimeters are reliable and accurate where 5G is deployed in the U.S.

The FAA said Tuesday it had cleared 90% of the U.S. commercial fleet, including Boeing’s fleet of passenger airplanes, for operations near 5G towers when weather is poor.

For travelers who have been affected, a flexible travel policy is now in effect, Alaska spokesman Ray Lane said.

To check the status of an Alaska Airline flight, go to alaskaair.com or the airline’s mobile app. åå

Janice Podsada; jpodsada@heraldnet.com; 425-339-3097; Twitter: @JanicePods.