Off-Duty Pilot Tries to Disrupt Engines on Alaska Airlines Flight

An off-duty pilot who was in a jump seat in the cockpit of an Alaska Airlines flight has been charged with more than 80 counts of attempted murder after he tried to disrupt the engines during a flight on Sunday, prompting the plane to divert to Portland, Ore., the authorities said.

Flight 2059, operated by Horizon Airlines, an Alaska Airlines regional subsidiary, left Everett, Wash., around 5:23 p.m. and was headed to San Francisco when it reported “a credible security threat related to an off-duty Alaska Airlines pilot who was traveling in the flight deck jump seat,” Alaska Airlines said in a statement on Monday.

“The jump seat occupant unsuccessfully attempted to disrupt the operation of the engines,” Alaska Airlines said in the statement, adding that the captain and first officer “quickly responded, engine power was not lost and the crew secured the aircraft without incident.”

A pilot told an air traffic controller that the man had tried to cut the plane’s engines, according to an audio recording posted on LiveATC.net, which shares live and archived recordings of air-traffic-control radio transmissions.

“We’ve got the guy that tried to shut the engines down out of the cockpit,” the pilot said, “and he doesn’t sound like he’s causing issues in the back right now. I think he is subdued.”

The pilot asked that law enforcement meet the plane upon landing.

The Port of Portland Police Department said in a statement that the flight crew “was able to detain the subject and the flight landed safely at Portland International Airport just before 6:30 p.m.”

The man was taken into custody without incident. The department identified him as Joseph D. Emerson.

According to the Multnomah County Sheriff’s Office, Mr. Emerson, 44, was booked into jail on Monday morning on more than 80 charges of attempted murder, a felony; more than 80 counts of reckless endangerment, a misdemeanor; and endangering an aircraft, a felony.

There were four crew members and 80 passengers on board the flight, a spokeswoman for Alaska Airlines said. It is not uncommon for off-duty pilots to use cockpit jump seats to commute to and from work.

A spokeswoman for the Federal Aviation Administration referred questions to the local authorities.

“All passengers on board were able to travel on a later flight,” Alaska Airlines said. “We are grateful for the professional handling of the situation by the Horizon flight crew and appreciate our guests’ calm and patience throughout this event.”