Asiana Flight 271 took off just after 3 p.m. bound for Seoul, South Korea with 179 passengers and 16 crew on board. Several witnesses on the ground near the airport say as the plane was ascending, they heard several loud explosions and flames shooting out of the left engine.
"We heard several intermittent booms, went outside to see what it was to find fire coming out of the left engine," witness Lois M. said. "Each time it boomed, fire shot out of the engine."
Passengers told KOMO News one person yelled out, "One of the engines is out!"
"I live in Federal Way and about five minutes ago a plane was going over and me and a neighbor were talking and a thunder like noise was coming from the plane," another witness said. "It wasn't regular thunder, this was constant about 20 times."
Another witness said they saw flames shoot from the engine for about 8 to 9 seconds.
Airport spokeswoman Perry Cooper said it was not immediately clear what might have caused the flames. Federal Aviation Administration spokesman Mike Fergus said it could have been a backfire. Whatever the case, Cooper said, the pilots were able to maintain control of the aircraft.
"These aircraft can all travel with one engine out. They're designed that way," Cooper said. "It wasn't a situation where there was necessarily any real danger."
The plane dumped fuel over Puget Sound before landing without incident at about 3:30 p.m. and taxiing to the gate. No flames were seen when the plane landed.
David Campbell with the Airline Pilots Association said less fuel gives the plane a lower landing weight, which allows the plane to land at a slower speed.
Fergus said no one was injured and there were no major delays for other flights.
The FAA will investigate the incident and provide a report to the National Transportation Safety Board, he said.
Hyomin Lee, a spokeswoman for Asiana Airlines in Seoul, said some passengers would be rebooked on another flight Thursday.
What about the dumped fuel?
According to the Department of Ecology, most of the fuel dumped by the plane likely evaporated, leaving only a small amount to end up in the Puget Sound. Ecology officials plan to charter a helicopter to check for any areas that may have been hit harder than others.
The department said it received reports of droplets of the fuel falling in several areas, including the ferry Wenatchee while sailing near Bainbridge Island. The fuel droplets pose no health risks, the department said.