A commercial airline pilot landed on Seattle-Tacoma International Airport's central taxiway instead of the runway earlier this month.
According to the Puget Sound Business Journal, the pilot of an Alaska Airlines Boeing 737 inbound from Chicago made the mistake on Dec. 19. There were no other aircraft on the taxiway when the plane landed.
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There were passengers on board, but a Sea-Tac spokesman said that they probably had no idea the pilot made the error.
An aerial view of Sea-Tac Airport shows what appear to be four runways, but there are only three. One is a taxiway that pilots use to get to and from the gates when they take off or land. It was a taxiway where the Alaska Airlines pilot landed.
Some Sea-Tac taxiways cross the runways, while others, such as the one on which the Alaska Airlines flight landed, run parallel, the Business Journal said.
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Alaska Airlines and the Federal Aviation Administration are investigating.
According to the Business Journal, just days before the incident, the Port of Seattle had repaved one of the runways. It didn't have the usual black tire marks that runways usually have, which might have led to the pilot’s confusion.
The landing was the fourth to occur on a taxiway in the airport’s history, according to the Business Journal. The last time was in 2004.
On average, 855 flights arrive and depart from Sea-Tac Airport daily, or 312,000 a year.