A San Francisco-bound Horizon Air Embraer E175 diverted to Portland on October 22 after an off-duty pilot sat in the flight deck jumpseat tried to shut down the aircraft’s engines in flight.
After departing Seattle/Paine Field, flight AS2059 was en route at 31,000ft when an Alaska Airlines pilot identified as Captain Joseph Emerson tried to disable both engines by deploying the engine fire suppression system.
The crew were able to remove him from the flight deck and secure the aircraft – N660QX (c/n 17000948) – “without incident”, a spokesperson for Alaska Airlines said in a statement.
In a later statement, the operator said: "Engine power was not lost despite the off-duty pilot’s attempt to shut down the engines by engaging the Engine Fire Handle, also known as the fire suppression system. The fire suppression system consists of a T-handle for each engine. If the T-handle is fully deployed, a valve in the wing closes to shut off fuel to the engine.
"In this case, the quick reaction of our crew to reset the T-handles ensured engine power was not lost. Our crew responded without hesitation to a difficult and highly unusual situation, and we are incredibly proud and grateful for their skilful actions."
“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 issues in the back right now,” one of the pilots told air traffic control (ATC). “I think he’s subdued and other than that we’d like law enforcement as soon as we get on the ground and park.”
In a later transmission, the pilot is heard telling ATC that the individual was “in the back of the airplane” and that he seemed to have “settled down after one moment of going a little overboard.”
The crew revealed in their transmissions that the situation reached a Level 4 – the most serious – on the International Civil Aviation Organisation’s (ICAO) unruly passenger threat level system. This classification is for events where there is an attempted or actual breach of the flight crew compartment.
The flight landed without incident at Portland International Airport. The event is currently being investigated by law enforcement authorities.
“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,” the Alaska Airlines spokesperson added.
The twinjet touched down in the Oregon city at around 6.30pm local time (1.26am UTC). Alaska Airlines said passengers were able to continue to their destination on a later flight, which according to Flightradar24, left for San Francisco at around 8.45pm (3.45am UTC).
In a statement, the Federal Aviation Administration (FAA) said: "[We] engaged with Alaska Airlines and Horizon Air and [are] supporting law enforcement investigations into Sunday evening’s incident aboard a Horizon Air flight."
US Secretary of Transportation, Pete Buttigieg, added: "I am grateful for the professional flight crew and air traffic controllers who stepped up to guide this plane safely to Portland. FAA supports law enforcement in their response and will be focused on any safety considerations for the future that emerge from investigations."
Captain Emerson joined Alaska Air Group as a Horizon first officer in August 2001. In June 2012, Emerson left Horizon to join Virgin America as a pilot. Emerson became an Alaska Airlines first officer following Alaska’s acquisition of Virgin America in 2016. He became an Alaska Airlines captain in 2019. According to the airline, 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.
According to BBC News, Emerson, 44, faces charges of 83 counts of attempted murder, 83 counts of reckless endangerment and a single count of endangering an aircraft.
N660QX – which remains on the ground at its diversion airport – is a brand-new example delivered to Horizon Air on June 28, 2023. The General Electric CF34-powered aircraft is configured to seat 76 passengers in a two-class layout.