An off-duty pilot who allegedly tried to shut down a plane's engines during a flight told police after his arrest he had taken psychedelic mushrooms for the first time, prosecutors say.
Joseph David Emerson, an Alaska Airlines pilot, was arrested in Oregon on Sunday night and charged with 83 state counts of attempted murder and a single count of endangering an aircraft.
The flight crew reported he had tried to shut down the engines on a Horizon Air flight from Everett, Washington state, to San Francisco, California, while riding in the extra seat in the cockpit.
The federal charges also say he tried to grab the handle of an emergency exit after being restrained.
Horizon Air flight 2059 was diverted to Portland, where the plane carrying more than 80 people landed safely, and the 44-year-old suspect was detained by police.
A federal charge of interfering with a flight crew was made public on Tuesday, which said Emerson made casual conversation with the captain and first officer before trying to grab two red handles that would have activated the plane's fire suppression system and cut fuel to its engines.
After what the flight crew described as a brief struggle lasting around 30 seconds, Emerson left the cockpit, the FBI said.
The document also said he told officers he thought he was dreaming when he pulled the emergency shut-off handles, and had been depressed for the past six months.
It was not clear from the court document if Emerson was high on psychedelic - or magic - mushrooms when he was on the plane.
But an FBI agent wrote in an affidavit that the pilot spoke with police about the use of psychedelic mushrooms and "said it was his first time taking mushrooms".
State court documents say Emerson had taken "magic mushrooms" about 48 hours before the incident.
Flight attendants placed Emerson in wrist restraints and seated him in the rear of the aircraft, but as the plane descended he tried to grab the emergency exit handle, according to prosecutors.
They added that a flight attendant stopped him by placing her hands on top of his.
'I'm not OK'
Asked if Emerson took the mushrooms right before the flight, Kevin Sonoff, of the US Attorney's Office for the District of Oregon, said that was still under investigation.
The captain and first officer told police after the plane landed that Emerson had said, "I'm not OK" just before he reached up to pull the handles. They were able to stop him before he pulled the handles all the way down, the affidavit said.
Emerson walked calmly to the back of the plane after being told to leave the cockpit and told a flight attendant, "You need to cuff me right now or it's going to be bad", it is alleged.
Another flight attendant heard him saying, "I messed everything up" and "tried to kill everybody".
According to the affidavit, he asked police if he could waive his right to a lawyer, telling them: "I'm admitting to what I did. I'm not fighting any charges you want to bring against me, guys."
The affidavit said he added: "I pulled both emergency shut-off handles because I thought I was dreaming and I just wanna wake up."
Initial court appearance
The incident happened on a 76-seat Embraer 175 plane.
As an off-duty pilot, Emerson was authorised to ride in the cockpit's jump seat.
He is set to appear in Multnomah County court on Tuesday night.