SAN FRANCISCO -- The off-duty pilot accused of trying to crash an Alaska Airlines plane mid-flight in October was indicted by a grand jury on Tuesday, according to the Multnomah County, Oregon District Attorney's Office.
Joseph Emerson of Pleasant Hill, California, 44, has been indicted on 83 counts of recklessly endangering another person for conduct on Horizon Air Flight 2059, Multnomah County District Attorney Mike Schmidt said.
He's also being charged with one count of endangering an aircraft in the first degree.
Alaska Flight 2059 was full, with 83 passengers on-board when Emerson allegedly tried to shut down the engines of the San Francisco-bound flight in October. The flight was then diverted to Portland, Oregon.
Alaska Airlines said Emerson was sitting in the flight deck jump seat in the cockpit before the incident.
Emerson engaged with the pilots in "casual conversation" before allegedly trying "to grab and pull two red fire handles that would have activated the plane's emergency fire suppression system and cut off fuel to its engines," prosecutors said.
Emerson was heard in the moments prior to the incident saying something similar to, "I'm not right," preliminary information obtained by investigators indicated, according to a federal official briefed on the probe.
"After a brief physical struggle with the pilots, Emerson exited the cockpit," prosecutors said.
Emerson pleaded "not guilty" to "Interference with Flight Crew Members and Attendants" when he made his first appearance in federal court in October. The one charge could bring up to 20 years in prison.
Emerson is currently staying at the Multnomah County Detention Center, the DA's office said.
He is scheduled to be arraigned on Dec. 7 at 9:30 a.m.
Emerson's lawyers told ABC San Francisco affiliate KGO, they are "crafting a release plan" and expect him to be home with his family by the end of the week.