(NewsNation) — Former Alaskan Airlines pilot Joseph Emerson pleaded not guilty to state charges of attempted murder after an October incident wherein he is accused of trying to bring a flight down mid-air.

Emerson is accused of attempting to pull the fire handles on a Horizon Air flight while the plane was in the air. He is facing 83 counts of attempted aggravated murder for his actions.

Emerson was traveling in a jump seat in the cockpit on the flight from Everett, Washington, to San Francisco when he allegedly attempted to pull the fire handles. The off-duty pilot was on his way to a flight and it is common for crew on the way to assignments to travel in jump seats.

He was restrained by the crew and the flight made an emergency landing in Oregon where he was taken into custody.

According to court documents, Emerson admitted to using psychedelic mushrooms 48 hours before the flight and said he had not slept in 40 hours. He reportedly said “I’m not okay” before attempting to pull the fire handles, which would have shut down the plane’s engines.

After Emerson was restrained by the crew he was seated in the rear of the plane. He allegedly attempted to open an emergency exit before the plane landed, but was stopped by a flight attendant.

Three passengers sued Alaska Airlines, which operates Horizon Air, after the incident.