A "credible security threat" caused an Alaska Airlines flight from Everett's Paine Field to be diverted to Portland on Sunday, the airline confirmed to KING 5. The threat was related to an off-duty pilot, identified as 44-year-old Joseph Emerson, who "unsuccessfully attempted to disrupt the operation of the engines," according to the airline. The captain and first officer quickly responded, Alaska said, and engine power was not lost. According to the Allied Pilots Association, Emerson tried "to disable the aircraft engines while at cruise altitude by deploying the engine fire suppressions system." That would cause the engines to "cease operation," according to aviation expert Scott Hamilton. Read more: https://www.king5.com/article/news/local/public-safety/credible-security-threat-paine-field-flight-diverted/281-226138f9-a83b-4ffc-a578-73e654c12f66