PORTLAND, Oregon — An Alaska Airlines flight bound for San Francisco had to be diverted to Portland International Airport (PDX) on Sunday after an off-duty Alaska Airlines pilot attempted to "disrupt the operation of the engines," according to the carrier.
The plane departed from Everett, Washington, and was heading to San Francisco, California, on Oct. 22 when it reported a "credible security threat related to an authorized occupant in the flight deck jump seat," Alaska Airlines said. The suspect then attempted to deploy the engine fire suppressions system, which would have caused the engines to shut down.
Two pilots were able to subdue the man before engine power was lost. They followed Federal Aviation Administration procedures and guidance from air traffic control and diverted the plane to PDX.
The Port of Portland arrested 44-year-old Joseph Emerson early Monday morning. He faces 83 counts of attempted murder, 83 counts of reckless endangerment and endangering an aircraft.
Paul Stephen, a passenger aboard the plane, said he was seated just behind the cockpit. Less than a half-hour into the flight, a flight attendant got on the intercom and said that they were diverting the plane.
"The passengers didn’t know what was going on," Stephen said. "We were looking at each other. Nobody knew anything ... You are sitting there, you don’t know if it is the plane, the pilot, if it is someone having a heart attack …”
Then, Stephen said he saw the cockpit door open.
"A gentleman walks out; he's got his hands crossed in front of him and he walks to the back of the plane by himself," he recalled. "The pilot sticks his head out, closes the door and we're on our merry way."
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One of the pilots told air traffic controllers that the man who posed the threat had been removed from the cockpit.
“We’ve got the guy that tried to shut the engines down out of the cockpit. And he — doesn’t sound like he’s causing any issue in the back right now, and I think he’s subdued,” one of the pilots said on audio captured by LiveATC.com. “Other than that, we want law enforcement as soon as we get on the ground and parked.”
Stephen still didn't understand the situation until the plane had landed and a handful of police officers got on board, escorting the same man out.
“I think if I knew what happened and I let this guy walk past me," he said, "me and others wouldn’t have let that happen.”
There were four crew members and 80 passengers aboard. No one was injured.
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Emerson first joined Alaska Air Group as a Horizon First Officer in August 2001, according to Alaska Airlines. He left in June 2012 to join Virgin America as a pilot. After Alaska acquired Virgin America in 2016, Emerson became an Alaska Airlines First Officer, then started his role as a captain in 2019.
"Throughout his career, Emerson completed his mandated FAA medical certifications in accordance with regulatory requirements, and at no point were his certifications denied, suspended or revoked," Alaska Airlines said in a news release.
The airline carrier has not released any additional details about the security threat. Law enforcement agencies, including the FBI, are investigating.
Horizon Air was operating the plane, Alaska Airlines flight 2059. The airline is a subsidiary of Alaska. All passengers were able to travel on a different flight.
"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," Alaska Airlines said.
According to retired commercial pilot Jim Hummel, it's common for off-duty pilots to hitch a ride in a cockpit jump seat.
"Every day there are off-duty pilots riding in the jump seat because there are pilots, thousands of pilots (who) commute to work on a daily basis," Hummel said.
What isn't common is for pilots to deploy a plane's engine fire suppression system, either accidentally or on purpose. They shut off the flow of fuel to the engines, turning them off.
“It was an intentional reach," Hummel offered. “Fire handles are red, so you can’t mistake them for anything else in the cockpit.”
Editor's note: The Associated Press contributed to this story.
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