More details emerge after off-duty pilot allegedly tried to shut off engines on Alaska Airlines flight

The off-duty pilot faces charges including 83 counts of attempted murder.

The off-duty pilot accused of trying to crash an Alaska Airlines passenger plane allegedly tried to shut down the engines "by engaging the Engine Fire Handle," according to the airline.

The fire suppression system on the plane consists of a T-valve handle for each engine, and if those handles are fully deployed, a valve in the wing closes to shut off fuel to the engine, Alaska Airlines said.

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The "quick reaction of our crew to reset the T-handles ensured engine power was not lost," Alaska Airlines said.

At the time of the Sunday incident, off-duty captain Joseph David Emerson was sitting in the flight deck jump seat, which is in the cockpit, Alaska Airlines 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.