SAN JOSÉ, Calif. (KGO) — By simply pulling a lever and pressing a button, power and fuel to an aircraft’s engine can be cut off by fire extinguishers.
This is what was allegedly attempted by off-duty pilot Joe Emerson in the cockpit of an Embraer 175 during a flight from Everett, Washington, to San Francisco.
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A look inside a similar plane can give us an idea of how it might have happened.
Jon Welte, CEO of the Hiller Aviation Museum, showed us what things look like in a Boeing 737, a plane with a larger cockpit but similar controls.
The emergency controls for the number one and number two engines are what Emerson tried to operate during the flight, although they are only to be used in the event of a fire.
“What I would do is pull that lever up, which is hard to do,” Welte said. “I have to press this safety button first so this can’t happen by accident. When I pull it up, it cuts off the flow of fuel going to the engine. It also cuts off the hydraulic system and the power supply.”
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Turning the lever would trigger the fire extinguishers and if this was done for both engines it would leave the plane with no way to fly normally.
In the Embraer 175 cockpit, these fire extinguisher controls are located at the top. They are easily accessible for a pilot seated on the cockpit jump seat, right between the two pilots. This is exactly where Emerson was.
“The flight was full, so all the seats were occupied, but the jump seat was available,” Welte said. “There are a number of airline staff who can sit in jump seats in a cockpit.”
This includes off-duty pilots who often fly to destinations where they will board an aircraft they will pilot themselves. Emerson was scheduled to be part of a flight crew in San Francisco on Monday.
Fortunately, control of the aircraft was never lost and the crew was able to divert to Portland.
Emerson’s mental health has been questioned, and Welte says airline pilots must undergo medical exams every six months.
“A very important part of this exam is to look at any mental illness issues or medications that may be affecting cognitive function, any psychological issues that may have arisen in the six months since the last first class medical exam,” said Welte.
These are questions we may find answers to in the future as Emerson now faces 83 counts of attempted murder.
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